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UTOMOBILE  CONSTKUCTION 

MD  KEPAIK 


A  PRACTICAL  GUIDE   TO    THE   DESIGN.   CONSTRUCTION.   AND 
REPAIR  OF  AUTOMOBILE  MECHANISMS 


MORRIS  A.  HALL 

Awiomslire  Brngime^riftf,  Konnerlv  Slanaicins  Mitor.  M'^t'.r  Lif*.    I>lttnr.  1^*  '•^mmt^mnt  I'ekirU, 
•Cc.;A«lhor off  "What  K««>r>  AaU>0i<jhilj><>wneri<hotild  Kmm."    M**inl>er.  Sn«  '.f'ty  of  Aoto- 
■Mibile  Eaciiur^n.  Member.  American  Society  of  Mechanical  Elncineer^ 


ILLUSTRATED 


MMERlCm  TECHNICAL  SOCIETY 

^HICAGO 


AMEKirAN  TECHNICAL  HOCIET? 


T 


INTRODUCTION 

'HE  modern  automobile  is  mechanically  a  fine  piece  of 
engineering  and  it  represenis  in  its  development  the 
product  of  the  best  technical  brains  of  the  country.  The 
engine  has  changed  from  the  halting,  wheezy,  unreliable  con- 
traption of  fifteen  years  ago  into  a  perfectly  dependable,  well- 
behaved,  and  sweet -running  mechanism  which  carries  its  owner 
at  high  or  low  speed,  in  the  heat  of  summer  or  the  cold  of 
winter,  over  all  sorts  of  road  with  exceedingly  rare  periods 
of  distress  or  failure.  The  same  evolution  has  taken  place 
with  each  part  of  the  automobile  until  practically  all  the 
\  changes  in  present-day  models  are  simply  refinements  of  the 

fs         existing  mechanisms.     No  expenditure  of  money  or  skill  has 
^       been  spared  to  make  the  automobile  as  near  perfect  as  pos- 
:^        Bible.    As  a  result,  it  stands  today  one  of  our  best  examples  of 
well-rounded  development,  a  device  which  has  had  more  to 
f>(        do  with  our  progress  in  production  manufacturing  in  the  last 
>        ten  years  than  any  other  single  machine  which  could  be  men- 
N^        tioned.     Therefore,  it  behooves  those  who  are  interested  In 
*         this  development  to  study  the  construction  and  design  factors 
^        with  great  attention.     Lessons  are   to  be  learned   from   the 
evolution  of  this  device,  from  the  failure  of  that  design,  and 
i         the  study  of  "near  perfection"  is  always  profitable. 

([  This  volume  has  been  designed  not  only  for  the  man  who 
is  interested  in  things  mechanical,  but  more  especially  for 
the  designer,  for  the  mechanic  who  Is  engaged  in  automobile 
construction  and  repair  work,  and  for  owners  and  chauffeurs 
who  wish  to  be  their  own  repairmen.  The  discussion  of  the 
construction  of  valves,  clutch,  transmission,  etc.,  is  confined 
mainly  to  the  standard  types  without  much  attempt  to  trace 
the  historic  background.  As  to  the  repair  sections,  there  are 
many  ways  of  effecting  repairs  on  an  automobile,  but  the 
advice  here  given  is  based  on  careful  observation  and  broad 
experience.  The  sujggestions  range  from  the  engine  to  the 
differential,  from  the  steering  gear  to  the  tires.  The  excep- 
tionally full  section  on  carburetors  and  carburetor  adjustments 
and  the  section  on  tire  vulcanizing,  with  the  description  of 
proper  tire  repair  methods,  will  be  found  especially  helpful. 
No  attempt  has  been  made  to  cover  "Ignition,  Starting,  and 
Lighting  Systems,*'  as  this  has  received  an  exhaustive  treat- 
ment under  that  title  issued  by  the  same  publishers. 


329371 


CONTENTS 


Page 
Engine  group  11 

General   engine   features 15 

rylinder    forms    and    const  nut  ion 22 

Pistons    and    accessories 48 

Ponnecl  Ing:  rods   61 

Crankshafts    72 

rrankcases 84 

Carburetors   and   carburetion 99 

Function   of   carburetor 99 

Effect  of  heavier  fuels 99 

Classification 101 

Throttle  valves   103 

Carburetor   operation    112 

Kerosene  and  heavy  fuel  carburetors 180 

Carburetor  troubles  and  remedies 194 

Inlet  manifold  design  and  construction 20r» 

Changes  in  design 20r> 

Heating  the  charge 209 

Inlet   manifold   troubles 210 

Fuel   supply 211 

Tank  placing  211 

Fuel  feeding 211 

Piping  and  connections 211; 

Reserve  tank   217 

Fuel  system  troubles  and  repairs 218 

Valves  and  their  mechanism 227 

Valve   features    227 

Poppet-valve   gears    232 

Repairing  valve   parts ^ 252 


COXTENTS 

Valvu  and  their  mechanUm  (continued) 

Sliding  sleeve  valves 271 

Rotating  valvee  278 

BxtaauBt  syatem    279 

Cooling  ■yatama    28G 

Water    cooling    28G 

Air  cooling  300 

Troubles  and  adjiistnieniB 302 

Lubrication  ayatem 305 

Motor  lubrication  30r. 

General   lubrlcallon    321 

Oils    and   greaapK 322 

Lubrication  troubles  and  remedies 32."i 

Bearings 330 

Flywheel  aub-group   337 

ChararleristiCH  of  flywheel 337 

Melhods  of   fasleiiinK    flywheel 33fl 

Flywheel   markings    3311 


Clutchea 


COXTKNTS 

Tap* 
Steering  group 445 

Steering  gears  445 

Steering  wheels 470 

Steering   rods    474 

Front-wheel   drive    480 

F^our-wheel   drive    482 

Electric  drive 489 

Front   axles    491 

Chassis  group    508 

VFranies    509 

Springs    530 

Shock   absorbers    549 

Final-drive    group    569 

Rear  axle   581 

Brakes    604 

Wheels  622 

Tires     645 

Rims  654 


s^lbg 


ilifiliisliisi    gf 


GASOLINE  AUTOMOBILES 


PART  I 


INTRODUCTORY 

Of  all  the  applications  of  the  internal-combustion  motor,  it  is 
safe  to  say  that  none  is  more  important  than  that  applied  to  the 
propulsion  of  the  modern  motor  vehicle — the  automobile — which 
nowadays  throngs  the  roads  and  streets  of  nearly  everj'^  country  in 
the  world,  and  serves  a  myriad  of  utilities  as  they  never  have  been 
and  never  could  be  served  by  animal  transportation. 

Standardized,  inexpensive  to  buy,  and  inexpensive  to  operate, 
almost  unfailingly  reliable,  and  proved  capable  of  use  in  the  hands 
of  even  the  most  unmechanical  of  operators,  the  automobile  is  at 
last  coming  fully  into  its  own.  Its  design  has  become  recognized  as  a 
branch  of  engineering  by  itself,  its  manufacture  constitutes  one  of 
the  greatest  of  the  mechanical  industries,  and  its  use  is  a  common 
necessity. 

Naturally,  in  so  tremendous  a  development,  there  is  sustained 
by  the  general  public  every  possible  sort  of  relationship  with  the 
automobile,  from  that  of  the  merely  casual  observer  and  occasional 
user,  to  the  more  interested  owner;  and  thence  on,  in  e.ver  closer 
touch  with  the  full  significances  of  this  field  of  engineering,  to  the 
high-skilled  and  well-paid  drivers  of  cars,  the  experts  who  repair 
them,  the  shopmen  who  build  them,  and  the  engineers  and  draftsmen 
who  design  them. 

All  along  this  line  there  is  an  increasing  need  for  knowledge — a 
demand  for  definite,  specific,  usable  information  concerning  the 
science  upon  which  the  motor  vehicle  is  based,  and  the  practice  upon 
which  its  construction  and  performance  are  founded. 

In  no  other  important  field  of  engineering  is  there  such  a  lack  of 
correct  and  authoritative  literature  as  in  the  automobile  field. 

This  undoubtedlv  is  due  to  two  conditions  that  have  been 
involved  in  the  rapid  growth  of  the  automobile  from  a  mere  experi- 
ment to  an  achieved  and  commercial  fact.    The  first  condition  is 


2  GASOLINE  AUTOMOBILES 

the  circumstance  that  the  men  who  have  deeply  studied  the  auto- 
mobile from  an  engineering  standpoint,  and  who  are  best  informed 
about  it,  have  not  had  the  time  to  place  upon  paper  the  facts  with 
which  they  are  acquainted.  The  second  condition — resulting  from 
the  rapid  development  of  automobile  design  and  engineering  practice 
has  left  no  time  for  the  establishment  of  a  formulated  science,  upoD 
which  textbooks  of  a  genuine  and  permanent  authority  may  be  based. 

What  follows  will  be  an  advanced  and  comprehensive  treatment 
of  the  very  latest  devices  applied  in  automobile  engineering.  AU 
are  carefully  described,  their  essentials  fully  analyzed,  and  their 
important  details  fully  illustrated. 

Historical  material  of  any  kind  is  useless  in  a  work  of  this  sort, 
which  is  intended  primarily  for  the  man  in  the  shop,  who  does  the 
actual  work  of  coinpleting  the  car  in  the  first  place,  and  the  man  in 
the  garage  who  keeps  it  in  running  order  thereafter.  It  will  suffice  to 
say  that  while  most  of  the  worthy  efforts  and  early  progress  in  the 
development  of  the  explosion  motor  and  the  automobile  were  made 
abroad,  American  designers  and  American  workmen  have  since 
shown  the  way  in  this  field  to  the  whole  world,  so  that  today  we  import 
a  negligible  number  of  motors  and  cars,  while  we  export  to  every  other 
country  of  the  world. 


GASOLINE  AUTOMOBILES  3 

the  rear  wheels,  and  thus  propels  the  car.  Of  necessity,  this  indudes 
the  rear  axle,  while  the  front  axle  is  usually  grouped  with  the  rear; 

(5)  the  steering  de\4ce,  for  controlling  the  direction  of  motion;  and 

(6)  the  frame,  upon  which  all  these  and  their  various  accessories 
are  hung,  with  the  springs  for  susi>ending  the  frame  upon  the  axles 
of  the  car.  There  is,  of  course,  a  seventh  group,  the  body,  but  that 
need  not  be  discussed  here,  since  reference  is  now  made  only  to  the 
medianical  parts. 

Enguie  Qroup.  In  the  large  diagram  of  a  modem  motor  car. 
Fig.  if  the  sectional  side  \new  is  shown  above,  and  the  plan  \new 
below.  In  this,  note  that  the  engine  is  placed  at  the  front  of  the 
outfit.  This  is  now  the  position  nearly  all  modem  motor  car  manu- 
facturers use.  A  few  cars  have  the  motor  located  on  the  rear  axle 
to  save  the  parts  necessary  for  connecting  the  two,  while  formerly 
the  middle  position  was  a  favorite  one.  The  purpose  of  the  engine 
is  to  generate  the  power.  This  is  done  by  the  drawing-in,  compressing, 
and  exploding  of  gas  produced  from  gasoline. 

Cylinder  and  Crankshaft  Subgroup.  All  thb  work  is  actually  done 
within  the  cylinder,  which  really  forms  the  basic  working  medium  of 
the  engine.  The  actual  drawing4n  of  the  gas,  its  compression  and 
explosion  are  accomplished  by  the  movements  of  the  piston  up  and 
down  in  the  cylinder  bore.  The  piston  is  moved  upward  and  down- 
ward by  the  rotation  of  the  crankshaft  except  when  the  explosion 
reverses  the  situation,  and  the  piston  moves  the  crankshaft,  to  which 
it  is  attached  by  means  of  the  connecting  rod.  The  pbton  is  made  to 
fit  tightly  in  the  cylinder  by  means  of  piston  rings,  which  are  com- 
pressed into  slots  formed  in  the  outside  of  the  piston  for  this  purpose. 
The  connecting  rod  is  forced  to  rotate  by  its  attachment  at  the  lower 
end  to  one  of  the  crankpins  of  the  crankshaft,  which  is  held  in  the 
crankshaft  bearings  fastened  in  the  crankcase.  It  is  enabled  to  turn 
slightly  at  the  upi>er,  or  piston,  end  by  being  pivoted  on  the  piston 
pin  or  wrist  pin.  For  convenience  the  crankcase  is  usually  made  in 
two  parts,  caUed  the  upi>er  and  lower  haltes.  Sometimes  the  c>'linder 
is  also  made  with  a  removable  cylinder  head,  or  a  smaller  removable 
cylinder  cover.  The  majority  of  modem  motors  have  the  valves 
enclosed  by  removable  cylinder  talte  covers. 

Carhuretion  Sub-Group.  The  production  of  the  gas  necessitates 
what  b  caDed  a  carburetor^  a  good-sized/iie2  tank,  and  piping  to  connect 


GASOLINE  AUTOMOBILES 


the  two.    The  fuel  is  not  always  pure  and  must  be  filtered  through  a 
strainer.    A  cock  must  be  provided  in  the  piping  for  turning  the  flow 


GASOLINE  AUTOMOBILES  5 

manifofd.  These  and  other  parts,  the  functions  and  construction 
of  which  will  be  explained  in  full  later  on,  constitute  the  carburetion 
sub-group. 

Inlet  and  Exhaust  Valves.  In  order  to  get  the  gas,  which  is 
produced  by  the  carburetion  group,  into  the  motor  cylinders  at  the 
proper  time  and  in  the  proper  quantity,  inlet  valves  are  necessary. 
These  valves  are  operated  by  cams  on  a  camshaft.  The  camshaft, 
which  will  be  explained  in  detail  later,  is  driven  from  the  crankshaft 
of  the  engine.  After  the  gas  has  been  admitted  into  the  cylinders, 
compressed,  and  exploded,  it  is  of  no  further  use  and  must  be  removed 
from  the  cylinders.  As  this  must  be  done  at  the  proper  time,  and  as 
the  proper  quantity  must  be  removed,  additional  valves  known  as  the 
exhaust  valves  are  necessary.  These  are  also  operated  by  cams  on  a 
camshaft,  driven  from  the  crankshaft. 

Exhaust  System.  The  exhaust  gases  pass  from  the  cylinder 
through  a  particular  pipe,  known  as  the  exhaust  manifold,  and  thence 
to  the  back  of  the  car.  As  there  remains  considerable  pressure  in 
these  gases  when  allowed  to  escape  freely,  they  make  much  noise 
and  considerable  smoke,  so  that  all  cars  are  required  by  law  to  carry 
and  use  a  muffler.  The  exhaust  gases  pass  through  this  and  thence 
out  into  the  atmosphere.  This  whole  group  of  parts  is  called  the 
exhaust  system. 

Ignition  System.  The  explosion  comes  in  an  intermediate  stage. 
It  is  produced  by  means  of  an  electric  spark,  made  within  the  cylinders 
by  means  of  a  spark  plug.  The  electric  current,  which  is  the  original 
touree  of  this  spark,  may  be  produced  by  a  rotary  current  producer, 
known  as  a  magneto,  or  it  may  be  taken  from  a  battery.  In  either  case, 
the  current  must  be  brought  up  to  a  proper  strength,  and  the  various 
sparks  must  be  produced  at  the  exact  time  they  are  needed.  All  this 
calls  for  auxiliary  apparatus.  Moreover,  the  current  producer,  if  it 
be  a  magneto,  must  be  driven  from  some  rotating  shaft,  and  there 
must  be  a  suitable  place  provided  on  the  engine  to  attach  it  in  such  a 
way  as  to  provide  for  quick  and  easy  removal.  All  this,  as  a  complete 
unit,  is  called  the  ignition  system.  A  complete  treatment  of  this 
subject  will  be  found  under  "Electric  Equipment  for  Gasoline  Cars". 

Cooling  System.  A  great  amount  of  heat  is  created  by  the  fol- 
lowing explosion  and  subsequent  expanding  and  exhausting  of  the 
gas.    Some  idea  of  this  may  be  gained  from  the  t>vo  following  state- 


fi  GASOLINE  AUTOMOBILES 

meiits:  The  explosion  temperature  often  runs  up  as  high  as  3000°  F., 
and  the  exhaust  temperature  frequently  is  as  high  as  1500°  F,  In 
order  to  take  away  this  heat,  which  communicates  itself  to  the  walls 
and  to  parts  of  the  engine  wherever  it  comes  in  contact  with  them, 
and,  by  conduction,  to  other  parts  with  which  it  does  not  contact, 
the  parts  which  are  exposed  to  the  greatest  heat  are  surrounded  by 
hollow  passages,  called  jackets,  through  which  water  is  forced,  or 
allowed  to  flow.  This  might  be  called  a  collector  of  the  he^t,  for  it 
is  tlien  conducted  to  the  radiulor,  a  device  for  cooling  the  water. 
It  is  there  cooled  off  and  then  used  again.  In  order  to  cireulate 
the  water,  a  removable  pump,  driven  from  some  rotating  shaft,  is  used. 
All  this,  with  the  necessary  piping  to  connect  the  various  parts,  is 
called  the  cooling  system. 

On  some  cars,  notahlj'  the  Franklin,  and  on  motorcycles,  there 
is  another  type  of  engine  with  an  air-cooled  system.  This  type  will  be 
taken  up  later. 

Lubricatiim  System.  To  make  the  various  parts  rotate  within 
one  another,  bearings,  or  parts  specially  designed  to  facilitate  easy 
and  efficient  rotation,  must  be  used.  In  and  on  all  such  bearings 
a  form  of  hibricant  is  neces.'Miry.  also  between  all  sliding  parts. 
Id  order  to  have  ii  copious  supply  of  oil  at  certain  points,  various 


GASOLINE  AUTOMOBILES  7 

Lighting  System.  Nearly  all  modern  motor  cars  have  an  electric 
lighting  system.  This  includes  an  electriocurrent  generator;  a  battery 
to  retain  the  electric  current  until  needed;  suitable  governing  devices 
to  control  the  generation  and  flow  of  current;  lamps  to  use  the  current; 
wiring  to  connect  them  with  the  soiwce;  switches  to  turn  the  current  on 
and  off;  and  other  parts. 

Flywheel,  At  one  end  of  the  engine  shaft  is  the  flywheel.  This 
is  a  large,  wide-faced  member  of  metal,  comparatively  heavy,  the 
fimction  of  which  is  to  store  energy  (by  means  of  rotation)  as  the 
engine  produces  it  and  to  give  it  back  to  the  engine  at  other  parts 
of  the  cycle  when  energy  is  needed,  and  none  is  being  produced.  In 
short,  it  is  a  storehouse  of  energy,  absorbing  the  same  from  the  engine 
and  giving  back  the  excess  when  it  is  needed.  In  general,  this  effect 
is  greatest  when  the  mass  of  metal  is  farthest  from  the  center,  con- 
sequently fl^-wheels  are  made  of  as  large  a  diameter  as  is  possible, 
considering  the  frame  members.     Note  this  in  the  illustration.  Fig.  1. 

Clutch  Group.  The  clutch  is  generally  located  inside  the  rim  of 
the  flywheel.  This  is  a  device,  by  means  of  which  a  positive  connec- 
tion can  be  made  with  the  engine  or  a  disconnection  from  it  effected 
at  the  driver's  will.  When  such  disconnection  is  made  with  the  engine 
running,  it  will  continue  to  run  idly,  and  the  car  will  come  to  a  stand- 
still. Conversely,  when  the  positive  connection  is  made,  the  motor 
will  drive  the  clutch  and  such  parts  beyond  it  as  are  connected-up 
at  the  time.  This  arrangement  is  necessary  because  of  a  peculiarity 
in  the  gas  or  gasoline  engine  which  cannot  start  with  a  load,  but  must 
be  started  and  allowed  to  get  up  speed  before  any  load  is  thrown  upon 
it.  The  function  of  the  clutch,  then,  is  to  disconnect  the  balance  of 
the  driving  system  from  the  engine,  so  that  it  may  attain  the  necessary 
speed  to  carry  a  load.  When  this  has  been  done,  the  proper  gear  is 
engaged,  the  clutch  is  thrown  in,  and  the  engine  picks  up  its  load. 

Like  other  groups,  this  must  have  a  means  of  connecting  and 
disconnecting,  a  proper  place,  proper  fastenings,  means  for  adjust- 
ment and  removal,  means  for  lubrication,  and  easy  access  to  its  parts. 
All  this,  collectively,  is  called  the  clutch  group. 

Transmission  Group.  As  has  just  been  pointed  out,  the  gasoline 
engine  cannot  start  with  a  load ;  it  must  get  up  speed  first.  When  the 
load  is  first  applied  it  must  be  light.  This  necessitates  certain  gearing, 
so  that,,  when  starting,  the  power  of  the  engine  may  be  multiplied 


8  GASOLINE  AUTOMOBILES 

many  times  before  reaching  the  wheels  and  applied  to  the  propulsion 
of  the  car.  Furthermore,  it  has  been  found  convenient  to  have  a 
series  of  such  reductions  or  multiplications.  These  correspond  to  the 
various  speeds  of  the  car,  for,  obviously,  if  the  power  is  multiplied  by 
means  of  gearing,  it  is  reduced  in  speed  in  the  same  ratio.  This  whole 
group  of  gearing  is  the  tTansmiamm  or  gearsei,  and  the  various  reduc- 
tions are  the  low,  intermediaie,  and  high  speed  in  a  three-speed  gear- 
box; and  low,  mtermediale,  second,  and  high  in  &  four-speed  gearbox. 
A  gearbox  is  always  spoken  of  by  its  number  of  forward  speeds,  but 
there  is  in  all  of  them,  in  addition  to  the  forward  speeds,  a  reverse 
speed  for  backing  the  car. 

In  the  usual  form,  these  gears  are  moved  or  shifted  into  and  out 
of  mesh  with  one  another,  according  to  the  driver's  needs.  For  this 
purpose,  shifting  gears  must  be  provided  within  the  gearbox,  that  is, 
the  arrangement  must  be  such  that  the  proper  gears  can  be  moved 
back  and  forth,  with  a  shifting  lever  outside  for  the  driver's  use,  and 
proper  and  accurate  connections  between  the  two.  The  gears  must 
be  mounted  on  shafts,  these  in  turn  on  bearings,  the  bearings  must, 
be  supported  in  the  gear-case,  and  this  must  be  supported  on  the  frame. 
In  addition,  there  must  be  suitable  provision  in  tlie  gear-case  cover 


GASOLINE  AUTOMOBILES  9 

mission— to  an  inclined  one — the  driving  shaft — with  as  little  loss 
as  is  possible. 

Rear  Axle  and  DifferentiaL  The  driving  shaft  drives  the  rear 
axle  through  some  form  of  gear,  either  hevely  worm,  or  other  variety, 
and  is  usually  a  two-part  shaft.  The  reason  for  cutting  the  rear  axle 
is  that  each  wheel  must  be  driven  separately  in  rounding  a  curve,  for 
one  travels  a  greater  distance  than  the  other.  This  seemingly  com- 
plicated act  is  produced  by  a  simple  set  of  gearing  called  the  differen- 
tied,  which  is  located  within  the  driven  gear  in  the  rear  axle.  Each 
half  of  this  is  fixed  to  one  part  of  the  axle  shaft.  All  these  gears  and 
shafts  must  have  bearings,  lubrication,  means  for  adjustment,  etc. 
On  the  outer  ends  of  the  axle  shafts  are  mounted  the  rear  wheels, 
which  carry  some  form  of  tires  to  make  riding  more  easy.  The 
brakes  are  generally  in  a  hollow  drum  attached  to  the  wheels.  All 
this  goes  to  make  up  the  driving  system. 

Steering  Group.  The  front  wheels  perform  a  different  function. 
They  are  hung  on  the  steering  pivots,  so  that  they  can  be  turned  to 
the  right  or  the  left  as  desired.  In  order  to  have  the  wheels,  work 
together,  a  rod,  called  the  cross-connecting  rod,  joins  them,  while  the 
motion  is  imparted  to  them  by  means  of  another  rod,  called  the 
steering  link,  which  joins  the  steering  lever  or  arm  with  the  right-hand, 
or  left-hand  steering  pivot.  The  last-named  lever  projects  downward 
for  this  purpose  from  the  steering-gear  case  and  is  moved  forward  and 
backward  by  the  rotation  of  the  steering  wheel  in  the  driver's  hands. 

The.  transformation  of  the  rotation  or  turning  motion  of  the  hand 
wheel  into  a  longitudinal  movement  is  accomplished  within  the 
steering-gear  case  by  means  of  a  worm  and  gear,  a  worm  and  partial 
gear,  or  by  a  pair  of  bevel  gears.  All  these  parts  need  more  or  less 
adjustment,  lubrication,  fastening  means,  etc.,  the  complete  group 
being  designated  as  the  steering  group. 

In  addition,  the  steering  wheel  and  post  carry  the  spark  and 
throttle  levers,  with  the  rods,  etc.,  for  connecting  them  to  the  igniting 
apparatus  (magneto,  timer,  etc.)  and  the  carburetor,  respectively. 
The  purpose  of  the  spark  lever  is  to  allow  the  driver  to  var>'  the  power 
and  speed  of  his  engine  by  an  earlier  or  later  spark,  according  to  his 
driving  ^leeds.  Similarly,  the  _throttle -lever  is  for  the  purpose  of 
opening  or  closing  the  throttle  in  the  intake  manifold  of  the  carbu- 
retion  system  and  regulates  the  amount  of  gas' entering  the  engine, 


10  GASOLINE  AUTOMOBILES 

thereby  increasing  or  decreasing  its  power  output,  or  speed.  Actually, 
these  are  parts  of  the  ignition  and  carburetion  systems,  respectively, 
but  they  are  usually  classified  with  the  steering  group,  because  they 
are  located  on  the  steering  wheel  and  post. 

Frame  Qroup.  Little  need  be  said  about  the  frame.  The  side 
merrthers  are  generally  supported  by  the  springs  at  the  front  and  rear 
ends.  The  springs  are  connected  to  the  axles  and  support  the  car. 
The/nrntcnMa-memfcerusuaily  supports  the  radiator  and  sometimes  the 
front  end  of  the  engine,  too.  The  rear  cross^member  usually  supports 
the  gasoline  tank  when  a  rear  tank  is  used.  The  other  cross-members 
may  support  the  engine,  transmission,  shifting  levers,  and  other  parts, 
according  to  their  location-  In  general,  the  number  and  character 
of  frame  cmss-members  is  slowly  changing;  the  modern  tendency 
is  toward  their  elimination.  By  narrowing  the  frame  at  the  front, 
the  engine  can  be  supported  directly  on  the  side  members.  With  the 
units  grouped,  the  same  is  true  of  the  other  important  units. 

Formerly,  practically  all  motors  and  transmissions  were  sup- 
ported on  a  sub-frame,  but  it  has  been  found  that  the  same  results  can 
he  obtained  when  this  extra  weight  is  eliminated.  Fig.  1  shows  a 
sub-frame. 

When  the  shifting  levers  are  placed  on  the  outside,  the^'  are 


GASOLINE  AUTOMOBILES  11 

ENQINE-QROUP  ELEMENTS 

GENERAL  FEATURES 

In  the  following  pages,  the  general  grouping  just  outlined  will  be 
followed  consistently,  so  that  the  student  and  w^orker  will  be  able  to 
follow  through  the  construction  and  repair  of  the  entire  car  in  a  reason- 
able and  logical  manner. 

The  principles  of  engine  design,  and  the  methods  and  details  of 
engine  construction  are  second  to  none  of  the  other  factors  that  com- 
bine to  produce  the  complete  modem  automobile. 

How  automobile  engines  oi>erate,  the  reasons  underlying  the 
various  details  of  different  designs,  and  the  relative  merits  of  different 
constructions  are  all  too  little  understood  bv  most  of  those  who  have 
to  do  in  a  practical  way  with  the  new  conveyance. 

Cycles  of  Engine  Operation.  In  all  motors  of  any  type  other 
than  those  in  which  there  is  a  perfectly  continuous  development  of 
the  power  through  constantly  rotating  elements — as  in  the  electric 
motor  and  the  steam  turbine — there  must  be  reciprocating  elements 
that  function  through  indefinitely  repeated  series  of  operations. 
Such  a  series  of  oi>erations  is  termed  the  cycle  of  the  engine  and  is 
abundantly  explained  later  in  the  book.  It  will  suffice  here  to  call 
attention  to  some  of  the  merits  and  demerits  of  the  different  cycles 
that  are  in  practical  use. 

Tiro-Cycle  Engines.  That  t^'pe  of  internal-combustion  engine 
in  which  everj'  stroke  in  one  direction  is  a  power  stroke  affords  a 
fyiATimiiin  of  power  impulses  to  any  given  number  of  engine  revolu- 
tionSy  but  because  of  other  limitations  it  is  not  always  possible  to 
make  m  two-cycle  engine  run  as  fast  as  a  four-cycle,  so  that  in  the 
majority*  of  cases,  the  number  of  explosions  in  a  given  period  of  time, 
or  for  a  given  vehicle  speed,  is  no  greater  with  a  two-cycle  than  with 
a  four-cj'de  engine. 

In  addition  to  this,  most  two-c>'cle  engines  are  often  difficult 
to  start.  They  are  likely  to  be  wasteful  of  fuel,  not  at  all  flexible  in  the 
matters  of  speed  and  pulling  power,  and  in  various  other  respects 
difficult  to  api^y  to  automobile  ser\'ice.  Their  greatest  merit  is 
their  eztreoie  »mplicit>'. 

Fawr-Cyde  Engines.  The  four-c>'de  engine  is  the  type  by 
wliic^  mne  hundred  and  ninety-nine  out  of  ever>'  thousand  present- 


12 


GASOLINE  AUTOMOBILES 


day  automobiles  are  propelled.  Varied  through  an  immense  number 
of  possible  forms,  and  with  minor  differences  in  the  product  of  every 
maker,  its  fundamental  functioning  }ias,  nevertlicless,  proved  to  be  far 
the  most  suitable  for  automobile  propulsion. 

With  the  succession  of  suction,  compression,  explosion,  and 
exhaust  strokes  affonled  hy  tlie  four-cycle  motor,  a  very  positive 
and  reliable  functioning  is  secured ;  and  by  the  expedient  of  a  sufficient 
cylinder  multiplication  to  afford  good  mechanical  balance  and  fre- 
quent power  impulses,  its  flexibility,  durability,  and  practical  quality 


GASOLINE  AUTOMOBILES 


four-cyclinder  vertical  engines  as  those  most  suitable  for  tlie  propul- 
sion of  the  average  automobile,  as  this  is  the  least  number  of  vertical 
cylinders  with  which  mechanical  and  explosion  balance  can  be  secured. 

The  use  of  six  cylinders,  with  the  crank  throws  120  degrees  apart 
and  the  explosions  occurring  once  for  everj- 120  degrees  of  crankshaft 
rotation,  affords  a  smoother-running  motor  than  the  four-c\linder. 

Still  better  than  the  "six,"  from  ever>-  standpoint  except  that  of 
cost,  which  has  prevented  its  wider  application  to  automobiles,  is  the  - 
V-shaped,  eight-cylinder  motor,  of  the  t\-pe  illustrated  in  Fig.  2, 


•VbIvb    MoUir 


which  gives  a  good  view  of  the  unit  power  plant  of  a  well-known 
American  machine.  In  both  of  these,  a  four-throw  shaft,  similar 
to  the  ordinary  four-cjlinder  crankshaft,  is  used,  is  mucli  cheaper  to 
manufacture  than  a  six-cylinder  crankshaft,  and  the  two  rows  of 
cylinders,  each  practically  constituting  a  separate  four-cylinder  engine, 
are  made  to  work  upon  the  common  crankshaft  at  9(1  degrees  apart. 

The  most  recent  tendency  in  car  motors  is  tow.ird  the  eight-cylin- 
der V-tj-pe,  following  the  marked  success  of  tills  form  in  aviation  use. 

Not  only  has  the  V-form  been  produced  in  the  poppet-valve 
form,  but  also  in  the  Knight  sleeve-vahe  type  an  example  of  which 


14 


GASOLINE  AUTOMOBILES 


is  shown  in  Fig.  3.  Furtliermore,  a  considerable  number  of  twelve- 
cylinder  V-type  motors  have  been  built,  a  good  example  being  shown 
in  Fig.  4. 

An  answer  to  the  demands  of  the  car  owners  for  the  flexibility 
and  power  of  the  multi-cylinder  types  has  been  recently  given  by  the 
issue  of  a  very  flexible  and  quick  starting  fourK-ylinder  motor  with  16 
valves,  two  intake  and  two  exhaust  valves  in  each  cjlinder.  Four 
of  these  of  widelj-  varjing  design  have  already  been  announced — 
Stutz.White,  and  Drexel  Motor  Car  Companies,  and  Wisconsin  Motor 
Company.    The  (ictails  cif  the  Wisconsin  motor  are  given  In  the  sec- 


GASOLINE  AUTOMOBILES  15 

cooled  and  also  very  light  in  weight,  eliminating  all  of  the  parts  and 
also  the  weight  in  the  water-cooling  system.  The  large  revolving  mass 
does  away  with  the  need  for  a  flywheel,  while  the  practical  elimination 
of  reciprocating  parts  reduces  vibration  to  a  minimmn. 

In  the  extreme,  motors  of  the  V-type  have  been  constructed  with 
sixteen  cylinders,  eight  in  each  group.  These  have  been  very  suc- 
cessful in  aeroplanes  and  motorboats,  particularly  the  latter. 

GENERAL  ENGINE  TROUBLES  AND  REPAIRS 

Engine  Troubles 

Deposits  of  Carbon  in  Cylinder.  These  are  loosened  by  intro- 
ducing two  or  three  tablespoonfuls  of  kerosene,  put  into  the  cylinder 
when  warm  through  spark-plug  hole.  Replace  the  spark  plug,  but 
do  not  connect  up  the  wires.  Turn  the  engine  over  slowly  to  work 
kerosene  back  of  rings.  Allow  it  to  stand  a  few  minutes.  Then 
connect  the  wires  and  start  the  engine  running  out  of  doors,  as  dense 
smoke  will  come  for  a  time.    Clean  spark  plugs  and  replace. 

Knocking.  Knocking  should  not  be  permitted.  It  is  likely  to 
result  in  injury  to  the  engine.  Ordinarily,  knocking  is  avoided  by 
retarding  the  spark.  In  starting  up  a  hill  where  considerable  power 
will  be  needed,  an  open  throttle  with  advanced  spark  should  be 
employed  before  beginning  the  climb.  Should  the  motor  begin  to 
knock  when  part  way  up  the  hill,  the  spark  should  be  gradually 
retarded.  Continued  pounding  is  caused  by  the  connecting  rod  and 
main-shaft  bearings  becoming  loose. 

Failure  to  Start.    Try  the  following  remedies: 
See  that  current  is  switched  on. 
See  if  throttle  valve  is  open. 
Be  sure  gasoline  tank  is  filled. 
Be  sure  gasoline  valve  is  open. 
See  that  air  can  enter  filling  cap  of  gasoline  tank. 
Flood  carbui^etor. 
If  weather  is  cold,  prime  cylinders  by  squirting  a  little 

gasoline  in  through  each  compression  relief  cock. 
See  that  spark  plugs  are  clean. 
Missing  of  Explosions.    See  "Troubles  with  Ignition  System." 
Popping  in  Carburetor.    Snapping  or  popping  in  the  carburetor 
is  caused  by  lack  of  gasoline,  so  that  the  mixture  fed  to  the  motor  is 


16  GASOLINE   AUTOMOBILES 

not  rich  enough,  and  as  a  result  it  burns  so  slowly  that  one  of  the 
admission  valves  may  be  open  before  the  charge  is  completeiy  billed, 
and  part  of  the  burning  charge  is  forced  back  through  the  pipe. lead- 
ing from  the  carburetor  to  the  combustion  chambers.  If  adjustment 
of  carburetor  is  such  that  a  weak  mixture  should  not  occur,  inspect 
the  gasoline  l>iping  system  carefully  for  an  obstruction.  Popping  in 
the  carburetor  may  also  be  caused  b.\'  a  leaky  Joint  in  the  piping  and 
by  connections  between  the  carburetor  and  the  combustion  chambers. 

Poor  Compression.  A'ahe  stem  ma,\-  be  broken  and  stickius- 
Valve  spring  or  ^alve  stem  ma,^-  he  clogged  with  dirt.  Cylinder  or 
explosion  chamber  may  be  cracked.  Piston  rings  may  be  broken  or 
turned  so  that  cuts  line  up,  allowing  prtssure  to  escape.  Cylinder 
may  be  giminmi.  Cam  ma\'  be  loose.  AVater  ma,\'  leak  into  cylinder 
through  plugs  in  cylinder  head.  Valves  may  not  seat  properly  due 
to  being  covered  with  soot.     A'aKes  may  ha\'e  to  be  reground. 

Engine  Starts,  but  Stops,  after  a  Few  Revolutions.  Engine  bear- 
ings may  have  seized  fnim  lack  of  lubricant.  There  may  be  too 
much  oil  in  crankcase.  Water  may  be  entering  cylinder  througli 
■  cracks  or  thnjugli  plugs  in  cylinder  head.  Carburetor  float  may  be 
sticking.  I'uor  water  circulation  may  be  due  to  broken  pump  shaft 
or  clogged  water  piping. 


Flf.  6.     Elufliiw  DiHDouat«d,  Sbowiug  CyUoden  Itemovcd 


18 


GASOLINE  AUTOMOBILES 


off.  When  this  \s  done,  the  appearance  of  the  ve^hicle  and  of  the 
work  is  very  much  Hke  that  presented  in  Fig.  5,  which  shows  two 
men  engaged  in  loosening  up  certain  parts  of  the  engine  preparatory 
to  taking  it  out. 

When  all  accessories  have  been  removed  or  loosened  up,  the 
holding  bolts  are  taken  out,  the  clutch  disconnected,  and  the  motor 
is  left  free  to  be  swung  out  by  means  of  a  small  crane  or  hoist.  In 
some  cases,  the  work  can  be  completed  without  disturbing  the  base 
■  of  the  motor,  as  in  Fig.  6,  which  shows  a  big  car  partly  disassembled 
for  repairs,  the  radiator  and  cylinders  having  been  removed  at  this 
stage.  The  trouble  here  was  found  within  the  cylinders,  hence, 
as  soon  as  they  had  been  removed,  the  balance  of  the  six-cylinder 
motor  and  its  chassis  could  remain  undisturbed. 

Hoists  and  Cranes.  Yale  &  Towne  Form.  For  lifting  out  an 
engine  or  other  unit  approximating  several  hundred  pounds  (possibly 
500  pounds  In  tlie  case 
of  a  big  engine)  an  effi- 
cient form  of  overhead 
hoist  is  needeti.  There 
is  nothing  better  than 
the  Yale  &  Towne 


GASOLINE  AUTOMOBILES  19 

would  complicate  the  job.  When  hung,  any  crane,  hotst,  or  any  block 
and  tackle,  can  be  hooked  into  it  and  when  the  load  has  been  lifted 
clear,  it  can  be  run  along  the  track  until  the  desired  point  is  reached. 
IF  this  expense  is  top  great,  the  same  results  can  be  obtained 
by  taking  a  sliding-door  track  and  suspending  it  from  the  ceiling 
beams.  Then  the  two  door  carriers  can  be  joined  by  the  large  end 
of  a  V-shaped  piece  of  steel,  not  less  than  }  inch  by  2  inches  in  section; 
while  the  carriers  are  separated  and  held  separated  by  a  simple  straight 
distance  piece.  The  lower  end,  or  point  of  the  V,  supports  the 
hook  or  eye,  whichever  is  used.    That  is,  from  an  old  sliding  door, 


High  01 

a  traveling  hoist  can  be  constructed  easily  and  quickly  to  handle 
engines  or  other  large  and  heavy  units. 

Floor  Type  of  Hoist  Support.  When  the  construction  of  the  roof, 
or  ceiling,  is  such  that  it  will  not  permit  a  suspended  hoist,  one  which 
works  from  the  floor  can  be  constructed.  This  consists,  as  Fig.  8 
shows,  of  a  double  track  beam  supported  on  castor-mounted  triangu- 
lar ends,  which  extend  as  high  as  the  garage  will  allow.  By  this 
means,  the  weight  can  be  lifted  clear,  and  the  entire  structure  move<l 
to  the  desired  place.    It  is  constructed  a  good  deal  like  those  \\iaX. 


GASOLINE  AUTOMOBILES 


described;  the  ends  are  fair  sized  angles,  say  2  inches  by  2  inches 
by  jV  inch;  the  braces  lighter  stock,  say  IJ  inches  by  IJ  inches  by 
^  inch;  and  the  castors  are  anything  that  ts  available.  It  is  not 
necessary  that  the  track  be  metal;  wood  can  be  used  if  it  is  wide 
enough  to  withstand  the  wear  of  the  wheels  and  deep  enough  to 
carry  the  heavy  loads. 

Commercial  Forms.  If  sufficient  money  is  available  to  purchase 
a  hoist,  these  makeshifts  are,  of  course,  unnecessary.  There  are  a 
number  of  portable  cranes  for  garages  on  the  market,  costing  from  t90 
up.  These  usually  have  a  U-shaped  base  of  heavy  cast  iron  with 
two  caatora  at  the  points,  and  one 
at  the  back  of  the  U.  At  the  back 
also  is  a  vertical  pillar  about  t 
feet  high,  with  a  curved  exten- 
At  the  end  of  the  extension 
is  a  grooved  pulley  carrying  a 
chain  hoist.  The  crane  runs  back 
to  a  sheave  and  set  of  gears  for 
winding  it  up.  It  has  a  suitable 
:lle  for  this,  as  well  as  a  long 
ing  handle   for   moving   the 


I   i>.B'Stul 


GASOLINE  AUTOMOBILES 


21 


round  stock,  put  through  the  drilled  holes  in  the  upper  or  supporting 
bar,  then  bent  over  and  shaped.  Before  anything  is  done,  the  ends 
of  the  bars  must  be  turned  down  and  threaded.  In  this  instance, 
there  is  a  hole  at  the  four  points  on  the  shelf  of  the  motor,  so  these 
holes  govern  the  size  of  the  ends  of  the  rods  and  also  their  spacing. 
On  almost  every  motor,  there  will  be  some  means  of  attachment  which 
can  be  studied  out  in  advance,  and  the  rig  built  to  fit  it. 

Portable  Engine  Stands.  If  the  engine  is  removed  from  the 
chassis,  the  first  thing  needed  is  a  suitable  engine  stand.  One  of  these 
is  shown  in  Fig.  10,  a  form  that  can  be  purchased  at  a  reasonable 
price,  and  which  possesses  many  excellent  features,   The  frame  is  made 


SuriitifiM.  OSio 


of  tubing,  which  gives  a  maximum  of  strength  in  a  minimum  of  space. 
The  oil  drip  pan  beneath  is  a  good  feature,  as  is  the  shelf  arrangement 
at  the  open  end.  The  large  castors  allow  it  to  be  moved  around  readily 
and  can  be  clamped  to  hold  it  any  place.  One  can  be  constructed 
out  of  heavy  galvanized  pipe  and  pipe  fittings  at  a  moderate  cost. 
This  form  of  engine  stand  holds  the  motor  in  its  natural,  orupright, 
position.  But  it  is  not  always  desirable  to  have  the  engine  in  that 
position ;  in  fact,  when  working  on  crankshaft  bearings  and  other  parts 
on  the  under  side,  it  is  necessary  to  have  it  inverted.  There  also  is 
work  which  makes  an  intermediate  position  desirable.  For  this 
purpose,  an  engine  stand  is  needed  which  can  be  turned  to  any  desired 


GASOLINE  AUTOMOBILES 


angle  and  fastened  there.  Such  a  stand  is  shuwn  iu  Fig.  11,  which 
represents  one  made  liy  the  Internationa]  Motor  Company,  Plainfield, 
New  Jersey,  for  its  own  use.  It  would  hardly  paj'  to  make  one  of  these, 
as  the  ends  are  castings  which  require  a  pattern,  but  if  a  couple  of 
garages  wanting,  say  two  each,  would  go  in  together,  it  would  pay  to 
have  patterns  made  for  the  four.  After  making  castings  for  their  own 
frames,  the  garage  owners  could  later  make  them  for  sale  if  they 
wanted  to  go  into  the  business.  The  sketch  explains  the  construction, 
butthis  explanation  might  be  addetl:   the  central  part,  projecting  from 


GASOLINE  AUTOMOBILES 


.  aluminum  alloys  has  commended  them  for  aviation  use  and  in  some 
cases  For  racing  automobiles. 

Method  of  Classifying  Cylinder  Forms.  Cylinders  are  generally 
named  according  to  two  things:  first,  the  method  in  which  they  are 
cast  or  produced;  and  second,  the  shape  of  the  combustion  chamber, 
or  arrangement  of  the  valves.  Thus,  according  to  the  first  method, 
they  are  divided  into  those  which  are  cast  separately,  that  is,  each 
cylinder  by  itself;  cast  in  pairs,  or  each  two  cylinders  cast  together; 
cast  in  threes,  a  modem  modification  fitted  to  the  six-cylinder  engine; 


and  cast  together,  or  en  bloc,  that  is,  all  of  the  cylinders  cast  as  a 
single  unit. 

According  to  the  second  method  of  naming,  cylinders  are  of  the 
L-head  type,  in  which  the  combustion  chamber  has  the  shape  of  an 
inverted  capital  letter  L,  formed  by  the  placing  of  all  valves  on  one 
side;  of  the  T-head  tj-pe,  with  the  combustion  chamber  shaped  like  a 
capital  T,  because  the  valves  are  equally  distributed ;  of  the  I-f ,vpe, 
or  valve-in-the-head  type,  so  called  because  the  combustion  chamber 
is  left  perfectly  straight  and  round  by  placing  the  valves  in  the  head; 
and  modifications  of  these. 


24 


GASOLINE  AUTOMOBILES 


Usually  in  speaking  of  the  cylinders,  both  namea  are  used  as  one, 
as,  for  instance,  those  of  Figs.  2,  3,  and  4,  all  of  which  happen  to  be 
aHke,  would  be  spoken  of  as  L-head  blocks.  Figs.  12  and  13  as  T-head 
pairs,  etc. 

Methods  of  Casting  Cylinders.  Cast  Separately.  The  early  and 
still  common  practice  in  the  building  of  multi-c\' Under  gasoline  motors 
is  the  casting  of  cylinders  separately.  This  policy  makes  it  easier  to 
secure  sound  castings,  simpler  to  machine  and  finish  them,  and  less 


GASOUNE  AUTOMOBILES  25 

water  jacket  of  sheet  meta^  of  the  buitt-on  form.  These  have  shown 
splendid  cooling  abilities,  but,  under  the  twisting  and  racking  of 
automobile  frames,  particularly  in  later  years,  with  the  use  of  more 
flexible  frames,  they  have  shown  too  much  tendency  toward  leakage 
to  become  popular. 

Cast  in  Pairs.  Just  as  soon  as  two-cylinder  and  four-cylinder 
engines  were  produced,  the  cast-in-pairs  form  of  cylinder  appeared 
and  is  almost  as  widely  used  today  as  then.  While  the  modem 
tendency  toward  smaller  bores,  compactness,  and  light  weight  has 
greatly  increased  the  number  of  cylinders  cast  en  bloc,  the  paired 


.  jl    i^^ft. 

'r^h 

ft^^± 

M^M| 

^^^^1 

■i 

A 

pi 

Studf  bkkcr  Sii-Cylinder  Motor.  Sho<ri: 


form,  including  the  cast-in-threes  modification  for  six-cylinder 
engines,  holds  its  own. 

Cast  Together.  The  great  advantage  of  having  the  several 
cylinders  of  one  motor  cast  together — en  bloc,  as  the  French  term  it — 
is  that  the  alignment  and  spacing  of  the  different  cylinders  is  thus 
rendered  absolute  and  permanent,  regardless  of  any  differences  in 
adjustment  that  may  otherwise  occur  in  assembling. 

This  construction  has  been  applied  to  a  large  proportion  of  the 
small  and  of  the  medium-sized  fours,  a  fair  proportion  of  the  larger 
fours,  and  to  a  considerable  number  of  sixes,  Fig.  14. 


GASOLINK   ArrOMOBILES 


GASOLINE  AUTOMOBILES 


27 


Another  advantage  is,  that  the  water  connections,  exhaust  and 
intake  manifolds,  etc.,  are  rendered  simpler  both  in  their  form  and 
the  mmiber  of  their  points  of  attachment. 

In  some  advanced  motor  designs,  the  passages  for  the  incoming 
mixtm«  and  for  the  exhaust  gases,  and  in  one  case  even  the  carbu- 
retor itself,  are  all  incorporated  in  the  main  casting. 


Pit.  18.    Section  threucb  Typienl  L-Hosd  CylindBr  with  Vilve 

Puta  in  Place 

Cmrtwt  ti  On  aUtm  Mitor  Cv  Ctrnfcnt.  DHnil.  Itirliifm 

Another  example  of  simple  construction  is  that  illustrated  in 
Fig.  15,  which  depicts  one  of  the  latest  Ford  motors,  in  which  cylin- 
ders, upper  half  erf  the  crankcase,  and  the  gearbox  are  all  cast  in  one 
piece.    The  lower  half  of  the  crankcase  and  gearbox  are  similarly 


GASOLINE  AUTOMOBILES 


constituted  of  another  simple  pressed  steel  unit,  while  a  second  casting 
is  iiseil  for  the  heads  of  the  cylinders  and  for  the  water  connection. 
Cylinders  Classified  as  to  Fuel  Chamber  or  Valves.  L-Ilead 
Forms.  In  the  L-head  form,  the  valves  are  all  located  nn  one  side, 
and  usually  hecause  of  this,  all  the  accessories  are  on  the  same  side. 
This  makes  a  lop-sided  engine,  with  carburetor,  inlet  pipe  or  manifold, 
magneto  and  wiring,  exhaust 
manj/old,  and  sometimes  elec- 
tric generator  and  other  parts 
all  grouped  on  one  side,  with 
little  or  nothing  on  the  other. 
While  a  disadvantage  in  four- 
and  six-cylinder  motors,  this 
is  somewhat  of  an  advantage 
in  eight-  and  twelve-cjlinder 
forms,  for  all  the  parts  and 
auxiliaries  ran  be  grouped  in 
the  V  between  the  cylinders, 
leaving  the  outside  clear.  On 
the  other  hand,  where  this 
grouping  has  been  found  unde- 


GASOLINE  AUTOMOBILES 


Ilf.  IB.    AluBUBum  CMting  Sat  Cylinden  aod  Upper  Half  oF  CtuikcH«  ja  Mumon  Ensiiie 


3U 


CASOLINE  AUTOMOBILES 


out  w  itlutUud  tin;  lifrtt.  well,  and  consequently  »liuuld  be  far  away  from 
xii&  lutat  (if  thu  t-xtiuust  manifold.     See  Figs.  12  and  13. 

/-  Ueatt  Furiim.  The  valve-in-the-head,  or  overhead  valve,  motor 
require-ti  an  1-hnad  cylinder,  because,  with  this  location  of  the  valves, 
there  is  lit)  HoivMsity  for  the  valve  pockets  of  the  other  forms.  Con- 
i>etiui!iitly  the  cylinder  can  be  straight  and  plain,  while  the  head, 
which  ia  sc|iariite,  is  fastened  on  instead  of  being  cast  integrally. 
It  may  have  either  the  L-  or  T-form,  according  to  the  location  of  the 
valveti  and  the  inlet  and  exhaust  manifolds.  Fig,  1 7  shows  an  I-head 
in  which  the  manifolds  are 
.tcated  on  the  opposite  side. 
Note  that  in  this  form  the 
c\iinder  head  is  integral,  the 
valves  being  set  in  cages 
which  are  removable,  as 
shown  in  the  view  of  the 
Interstate   Motor,    Fig.    18. 

The   foi 

clearl\-    separateti    as    they 

were  fomierlj-,  for  the  inelu- 

of  cylinder  heads 


GASOLINE  AUTOMOBILES 


31 


Cylinder  Repairs 

Remova]  of  Carbon.  One  of  tRe  things  every  repair  man  must 
do  is  remove  carbon.  A  good  method  is  the  introduction  of  a  metal 
object,  as  a  ball  or  a  piece  of  chain,  which  the  piston  is  allowed  to 
bomice  up  and  down  to  break  up  the  carbon.  This  is  successful, 
but  there  is  always  the  danger  of  the  part  getting  under  a  valve  or 
other  part,  and  causing  trouble. 

A  better  way  is  to  couple  up  a  number  of  short  lengths  of'chain — 
old  tire  chains  will  do — and  attach  them  to  the  flexible  shaft  of  a 
buiSng  or  polishing  outfit,  as  shown  in  Fig.  21.     This  chain  and 


shaft  end  can  then  be  introduced  into  the  combustion  chamber 
and,  when  the  current  is  turned  on,  the  rotation  breaks  off  all  carbon. 
Carbon  on  Fired  Cylinder  Heads.  When  the  motor  has  fixed 
cylinder  heads,  and  the  valve  opening  is  small,  this  is  not  always  a 
good  way.  Another  somewhat  similar  tool  can  be  constructed  to  go 
in  through  the  bore  of  the  cylinder  and  clean  off  the  cylinder  head  very 
nicely.  This  b  shown  in  Fig.  22,  at  work  (at  right)  and  in  detail 
(at  left).  It  consists  of  a  round  steel  brush  with  very  stiff  wire 
bristles  mounted  in  a  four-cornered  frame.  The  latter  should  be 
smaller  than  the  cylinder  bore  by  }  inch  or  so,  but  the  bristle 


32 


GASOLINE  AUTOMOBILES 


circle  should  be  full  diameter.     When  rotated  by  means  of  a  flexi 

shaft,  the  outside  bristles  have  a*  tendency'  to  throw  outward,  ao  tl 

this  device  will  clean  a  space  considerably  larger  than  its  diame 

when  at  rest. 

AV,';t:^r*r^_^^  ^Mien    the    elect 

-'^^''     motor,  or  electricity 

furnish    power    for   i 

device  shown  in  Fig. 

is  not  available,  ^mi 

results  can  be  obtair 

by    attaching  a    geai 

hand  drill,  as  shown 

Fig.   2.3.     When  this 

used,  however,  it  is  di 

cult   to  attain  suffici* 

speed     to     expand    1 

chain,   so   a   wire  bn 

with    fairly    long    wi 

nill     be     found     bet 


GASOLINE  AUTOMOBILES 


33 


/?//-  Supply  "i 


wire — long,  ^hort,  and  medium — will  come  in  handy,  also  brush  ends 
with  various .  diameters  of  shank,  with  copper  tubing  around  the 
actual  shaft,  or  flexible  tubing.  This  can  be  inserted  more  readily 
than  the  chain  "mop"  shown  in  Fig.  21.  But,  as  stated  above,  it 
cannot  do  equal  work,  because  it  cannot  be  revolved  so  fast. 

Compressed  Air.  If  the  cleaning  periods  for  the  engine  are  not 
too  far  apart,  the  greater  portion  of  the  carbon  can  be  blown  out  with 
compressed  air  by  using  the  air  after  a  chain  "mop"  or  wire  brush 
just  described.  To  use  the  air;  however,  calls  for  a  special  fitting, 
two  of  which  are  shown  in  Fig.  24.  The  one  at  the  right  is  the  most 
simple,  but  the  one  at  the  left  has  the  advantage  of  being  made  from 
pipe  fittings  instead  of  from  brass  tubing.  Both  screw  into  the  opening 
in  the  center  of  the  cylinder  head,  and  the  air  enters  through  the 
central  hole,  while  the 
carbfm  is  blown  out 
through  the  larger  annu- 
lar opening. 

Liquid  Solvent, 
Nowadays,  carbon  re- 
moval is  often  accom- 
plished by  means  of  liquid 
solvents.  Of  these,  ker- 
osene, denatured  alcohol, 
and  special  preparations 
are  the  most  widely  known  and  used.  Kerosene  is  used  when  return- 
ing from  a  trip.  Just  before  stopping  the  engine,  it  is  speeded  up 
and  a  little  kerosene  inserted  into  each  cvlinder.  This  loosens  the 
carbon  so  that  it  blows  out  through  the  exhaust. 

Denatured  alcohol  and  also  the  special  preparations  are  used 
in  much  the  same  way,  except  that  the  engine  is  not  run.  After 
returning  to  the  garage,  and  while  they  are  still  hot,  an  ounce  or  so  is 
placed  in  each  cylinder  and  allowed  to  stand  there  over  night.  On 
starting  the  motor  the  next  morning,  the  loosened  carbon  is  blown 
out  through  the  exhaust  pipe.  If  the  carbon  is  very  thick,  more 
alcohol  must  be  used  and  allowed  to  stand  for  a  longer  time.  By 
rejx'tition,  this  will  gradually  clean  out  all  there  is  in  the  cylinders. 

Removing  Carbon  by  Scraping  Tooh.  When  all  other  means  of 
removing  the  carbon  fail,  the  repair  man  must  go  back  to  hand 


Fig.  24.     Set-Up  for  BlowinK  Out  Carbon  from  Cylinder 
Heads  after  Looseninf; 


34 


GASOLINE  AUTOMOBILES 


serapers.  In  any  case,  these  are  the  most  simple  and  fully  as 
effective  as  any ;  provided  the  extra  time  needed  to  use  them  and  do  a 
good  job  is  available.  When  the  offending  member  has  been  brought 
out  so  it  can  be  handled,  the  removal  of  the  carbon  can  be  accom- 
plished in  a  few  minutes.  A  flat  piston  head,  like  that  shown  in 
Fig.  25,  can  be  scraped  off  with  any  knife  or  chisel,  but  a  special 
scraper  nia<le  from  an  old  file,  flattened  out  at  the  end,  and  ground 
down  so  as  to  present  one  sharp  edge  is  better.  Every  garage  man 
should  accumulate  from  five  to  a  dozen  shapes  and  sizes  of  scrapers 


GASOLINE  AUTOMOBILES 


at  the  top,  A,ia&  plain  straight  scraper  with  a  hooked  end.    Where 
there  is  plenty  of  room  to  work,  this  is  the  usual  tool.    That  at  B  is 


£,^ 


I'uHdiu  Typea  of  Cvbon  Scnpen 

somewhat  similar,  except  that  the  length  is  greater,  and  the  end  is 
bent.  This  allows  of  getting  up  or  down  further  than  with  the  straight 
tool.  A  form  with  a  double  bend,  no  handle,  and  a  scraper  at  each 
end  is  shown  at  C.  The  advantage  of  this  lies  in  getting  around 
cur\'e3  and  comers.  Still  another  at  D  has  the  same  curves  and  a 
^milar  double  curve  in  the  other  direction;  this  also  allows  working 
into  deep  corners.  That  indi- 
cated at  E,  with  a  shape  like  a 
hoe,  is  made  that  way  to  conform 
to  the  upper  curved  surface  of  the 
ordinary  combustion  chamber  and 
the  flat  top  of  the  piston.  The 
handle  screws  in,  and  to  insert  the 
tool  in  the  motor,  it  is  taken 
apart,  and  parts  put  in  through 
separate  holes  and  assembled  or 
screwed  tt^ther  inside.  The 
fonn  at  F  is  particularly  suitable 
to  the  eight-cylinder  Cadillac 
cylinder  head,  but  may  be  used 
with  any  motor  having  a  similar 
design.  It  is  a  rotary  form,  the 
central  plug  being  screwed  in,  to  replace  the  cylinder-bead  plug. 
Tbe  rotation  of  the  handle  outside  causes  the  tool  inside  to  tura 


Fig.  27.     Cor 

CyUndri.  .     

ud  Spu-k  Plug  SfacU 


GASOLINE   AUTOMOBILES 


around  over  the  surface  of  piston  top  and  combustion  chamber. 
When  used  against  the  top  it  is  pulled  upward.  It  is  pressed  down 
when  used  against  the  bottom,  or  the  piston.  Other  special  forms 
will  be  constructed  by  tlie  clever  workman  for  certain  motors  having 
peculiarities  which  make  these  specials  desirable  and  time-saving. 

Covtpress'ion  Indicating  Gage.  Before  taking  off  tlie  cj'Iinder  to 
look  for  trouble  inside,  the  repair  man  should  do  all  he  can  to  find  out 
what  and  where  the  trouble  is.  A  conjpression  gage  is  handy,  as 
this  indicates  the  pre,*^ure  in  e;i(.li  <■}  llinlcr.     Thr-e  sliould  nil  agree 


GASOLINE  AUTOMOBILES  37 

which  nine  persons  out  of  ten  would  blame  to  the  carburetor.  This 
gage  will  show  up  these  leaks. 

Locating  Noises  by  Means  of  a  Stethoscope.  Besides  this,  it 
should  be  borne  in  mind  that  there  are  many  sources  of  noise  in 
and  on  the  engine  other  than  that  produced  by  valves  and  valve 
motions.  In  fact,  the  noises  made  by  the  valves,  while  an  indication 
of  loss  of  power,  do  not  represent  anything  like  the  possibilities  for 
trouble,  indicated  by  a  piston  slap,  a  crankshaft  or  connecting-rod 
pound,  the  whirr  of  worn  timing  gears,  and  others.  In  order  to  locate 
such  sources  of  noise  exactly,  at  a  time  when  the  beginner  lacks  famil- 
iarity with  the  motor  and  its  troubles  he  should  purchase  or  borrow 
and  leam  to  use  a  stethoscope.  Fig.  28.  A  modification  of  the  sur- 
geon's well-known  instrument  is  now  made  for  use  in  automobile 
trouble  finding. 

The  stethoscope,  or  its  modification,  simply  magnifies  all  noise;  its 
constrdction  is  such  that  one  end  is  held  against  the  suspected  part, 
while  the  other  end  constitutes  an  ear  piece.  When  the  engine  begins 
to  make  a  great  deal  of  noise,  particularly  heavy  pounding  noises,  this 
should  be  brought  into  play.  With  the  motor  running,  place  the  free 
end  against  the  various  parts  of  the  engine,  going  slowly  from  one 
to  another.    In  this  way  it  will  soon  be  found  where  the  trouble  lies. 

A  piston  slap  is  not  so  easy  to  define  or  so  easy  to  repair.  It 
may  be  called  a  noise  which  comes  from  within  the  cylinders,  trace- 
able to  the  pistons,  or  to  one  piston,  as  the  case  may  be,  which 
sounds  very  much  like  a  sh^ft  pound,  except  that  it  is  a  louder  noise. 
It  occurs  when  pressure  is  put  on  the  piston,  as  at  the  beginning  of 
compression,  at  the  time  of  explosion,  or  at  times  at  the  end  of  each 
stroke.  It  is  said  to  be  due  to  different  causes.  Some  say  it  is 
caused  by  a  loose  piston  pin,  but  the  writer  knows  of  two  cases  in 
which  a  new  tight  pin  left  the  piston  slap  just  as  clear  and  distinct 
as  before.  Others  say  it  is  caused  by  rings  which  are  loose  up  and 
down  in  their  grooves,  but  in  the  cases  above,  new  rings  which  fitted 
tightly  in  this  way  did  not  help  any.  It  has  been  ascribed  to  a  piston 
which  was  out  of  round,  so  that  it  did  not  fit  the  cylinder,  and  also  to 
a  groove  and  shoulder  having  been  worn  in  the  cylinder  surface,  the 
piston  striking  this  each  time.  Whatever  is  the  real  cause,  and  the 
writer  is  inclined  to  blame  it  to  a  poorly  fitting  piston,  nothing  will 
really  remedy  it  but  a  new  piston^  complete  with  rings. 


GASOLINE  AUTOMOBILES 


Making  Gaskets.  Anyone  who  is  going  to  do  much  repair  work 
will  soon  liii\e  to  learn  tlie  art  of  making  gaskets,  for,  in  almost  every 
case,  the  removal  of  a  pajjer  gasket  is  accompanied  by  its  breakage, 
so  it  is  rendered  unfit  for  furtlier  use.  A  gasket,  it  might  be  explained, 
is  a  formed  sheet  of  hea\y  paper,  cardboard,  or  special  material  fitted 
between  two  surfaces  of  a  joint  wJiich  must  resist  the  leakage  of  gases 
or  Hquids  under  pressure.  By  means  of  the  bolts  or  screw  threads 
which  hold  the  two  parts  of  the  joint  together,  the  gasket  is  com- 
pressed and,  in  its  compressed  state,  it  resists  the  internal  pressure. 

The  following  method  of  making  gaskets  applies  alike  to  round, 
oval,  and  odd-shaped  ones,  which  cannot  be  said  of  special  tools  and 
fittings  for  gasket  cutting :  Select 
a  good  piece  of  heavy  brown 
wrapping  paper  or  special  gasket 
paper  without  too  many  WTinkles, 
free  from  cracks  or  flaws. 
Clamp  the  part  for  which  the 
gasket  is  to  be  made  in  a  vise  to 
steady  it  and  lay  the  paper  over 
it.     Then  go  around  the  edges 


GASOLINE  AUTOMOBILES 


CyUnder  Heads.  A  great  many  motors  have  detachable  heads, 
and  their  quick  remo\-a]  is  a  great  convenience,  when  there  is  carbon 
to  be  scraped  off,  pistons  to  be  looked  over,  or  other  internal  work 
to  be  done.  However,  replacing  them  is  never  quite  so  easy  as 
remo%'ing  them,  partly  on  account  of  the  cylinder  heads  themselves 
and  partly  on  account  of  the  pistons.  The  latter  are  particularly 
troublesome  when  the  cylinder  head  is  hinged.  The  cylinder  head 
should  be  repUtced  with  great  care,  and  after  replacement  it  is  fully 
as  important  to  bolt  it  on  property. 
It  one  bolt  or  a  series. of  bolts  is 
tightened  too  quickly  and  too  hard, 
it  is  likely  to  result  in  cracking  the 
cylinder  casting  or  the  head  casting 
or  both. 

Proper  Method  <^  Boiling  on 
Head.  Usually,  on  an  L-head  tyjte 
of  motor,  there  are  three  rows  of 
bolts  for  the  cjlinder  head — one  row 
along  the  middle,  screwing  into  one 
side  of  the  cj'linders;  another  row 
screwing  into  the  other  side  of  the 
cyUnders;  and  a  third  along  the  valve 
^de.  These  should  be  tightened  in 
order:  first  the  middle  bolts  of  the 
middle  line,  working  out  to  the  ends; 
next  in  turn,  the  middle  bolts  of  the 
back  of  the  cylinder,  the  middle  bolts 
of  the  valve  side,  the  ends  of  the 
cvlinder;  and  finally,  the  end  bolts  on  p^  30 
the  valve  side.  All  these  should  be  m-«h=.  w.™  cyiind«'Bo™r 
tightened  but  a  few  turns  at  a  time,  and  after  all  are  down,  a 
second  round  should  be  made  in  about  the  same  order,  to  give 
each  bolt  a  few  more  turns.  In  this  way  the  cylinder  head  casting, 
which  is  both  large  and  intricate,  is  slowly  pulled  down  to  the 
cylinder  straight  and  true  so  that  it  is  not  warped  or  twisted.  More- 
over, if  tbe  cylinder  is  pulled  down  straight  in  this  manner,  all  the 
bolts  can  be  tightened  more  than  if  the  first  bolt  were  tightened  ver>' 
mudi,  ftH"  tbe  latter  would  result  in  cocking  up  the  opposite  side. 


I 

1 

40                            GASOLINE   AUTOMOBIl.ES 

Checking  Up  Cylinder  Bore.    Before  any  work  is  done  upon  the 
cylinder  bore,  sin.'h  as  turning,  uriiiding.  etc.,  It  shoultl  l>e  checked  up 
very  carefuilj-.     An  expert  workman,  accustomed  to  the  tool,  would 
use  an  inside  micrometer,  but  when  this  tool  h  Jacking,  as  well  as  the 
experience  necessary  to  use  it,  a  fairly  simple  too!  which  can  Iw  used 
by  almost  anjone  may  be  constructed  as  follows :  Aa  shown  in  Fig.  30, 
a  short  angle  iron  forms  one  side  of  the  bore-measuring  part ;  its  length 
is  sufficient  to  keep  the  entire  tool  perfectly  ;ertical  when  the  c\linder 
is  vertical,  and  thus  gives  an  accurate  right-angle  measurement  of  the 
bore,     A  central  arm  is  fastened  to  this  and  the  framework  adjustably 

^M 

GASOLINE  AUTOMOBILES 


41 


the  micrometer  could  be  improved  by  eliminating  the  adjustable 
feature  and  making  the  frame  and  angle  face  a  solid  piece. 

Grinding  Out  Cylinder  Bore.  As  the  usual  amount  of  metal 
which  would  be  removed  from  a  worn  cylinder  would  not  exceed  a  few 
thousandths  of  an  inch,  grinding  should  be  the  process  used.  Other 
procesaes,  except  possibly  lapping  or  hand  grinding,  are  too  inaccurate. 
For  this  reason,  a  typical  grinding  set-up  is  shown  in  Fig.  31.  This 
shows  the  cylinder  bolted  against  a  large  angle  plate,  attached  to  the 
grinding  machine  table.  The  angle  plate  is  drilled  out  to  take  the 
bolts  which  hold  the  cylinder  casting  to  the  crankcase.  When  bolted 
up  for  work,  the  air  hose  is  connected  up  through  the  cylinder  head 
to  blow  out  the  dust  or  particles  ground  off.  Not  more  than  three  or 
four  thousandths  of  an  inch  should  be  taken  off  at  one  time;  if  more 
must  be  removed,  a  second  operation  over  the  surfaces  is  necessarj-- 

If  the  cylinder  is  worn  badly  enough  to  warrant  re-boring,  which 
calls  for  new  pistons  and  rings,  it  should  be  borne  in  mind  that  a 
standard  set  of  oversizes  has  been  adapted  by  the  Society  of  Automo- 
bile Engineers,  and  that  all  manufacturers  are  working  to  them,  by 
stocking  pistons  and  rings  according  to  these  dimensions: 


Oversize  Standard 


Inche*  Large 


For  1st  Oversize  10  thousandths  {.010") 

For  2d  0\'ersize  20  thousandths  {.020") 

For  3d  Oversize  30  thousandths  (.030") 

For  4th  Oversize  40  thousandths  (.040") 

Methods  of  Cylinder  Lapping.  When  the  cylinder  must  be 
lapped  or  ground  out  to  a  true  surface,  not  re-bored,  and  when  no  old 
piston  is  available  for 
this  purpose,  there  are 
several  methods  avail- 
able. One  is  to  use  a 
standard  lead  lap,  that 
is,  a  9c^  round  bar  of 
cylinder  size.  The  abra- 
sive may  be  either  emery 
and  oil,  carborundum 
dust  and  oil,  or,  in  some  cases*  ground  glass  and  oil  imbedded  in 
the  soft  surface  of  the  lead,  yet  it  projects  enough  to  abrade  the 


CyliDder 


42 


GASOLINE  AUTOMOBILES 


cylinder  surface  a  little  at  each  revolution.  Another  good  way  of 
doing  this  is  to  use  a  round  block  of  wood,  aa  shown  in  Fig.  32.  This 
is  made  a  close  fit  in  tlie  cylinder,  with  spiral  grooves  cut  in  its  surface, 
and  a  split  along  one  side.  Into  the  latter  a  wedge  is  driven  to  adjust 
for  wear.  The  emery  and  oil  is  put  on  the  surface,  and  the  lapping  is 
done  as  usual.  The  spiral  grooves  distribute  the  abrasive  evenly  so 
that  a  true  surface  results. 

Another  way  of  doing  this  is  to  make  a  large  special  boring  bar, 
say  2  inches  in  diameter,  and  drill  a  hole  into  this  at  right  angles. 
Then,  a  small  round  section  of  carborundum,  say  J  inch  in  diameter, 
is  placed  in  this  hole  with  a  spring  back  of  it  to  keep  it  up  against  its 
work.  This  arrangement  can 
BCijltndcr  Motor^^  -    |^  „,5j  „„  ,  ,„the,  the  bar 

being  rotated  in  the  usual  way, 
and  the  cylinder  fed  up  to  it 
either  by  the  carriage  feeder 
by  hand.  It  will  give  a  very 
fine  cylinder  surface,  and  use 
up  very  little  of  the  carborun- 
dum, which  costsvery  little  to 


GASOLINE  AUTOMOBILES 


43 


extended  end  is  that  a  very  minute  movement  of  the  piston  is  mag< 
nified  and  shown  as'a  considerable  movonent  at  the  end  of  the  wire. 
Thus,  it  is  possible  to  determine  the  dead  center  point  very  exactly. 

Repairins  Cracked  Water  Jackets.  Ver\-  often  the  first  cold 
spe)!  of  faU  niU  catch  the  owner  napping  in  the  matter  of  heat  for 
his  motor,  and  will  freeze  up  the  water,  which  finds  a  weak  spot  in  the 
water  jacket  and  cracks  it.  When  the  crack  is  smaU  and  localized, 
it  can  be  repaired  very  simply  as  follows:  Drill  each  end  of  the  crack 
as  shown  at  A  and  B,  Fig.  34,  and  screw  in  small  J-inch  brass  plugs  to 
prevent  the  crack  from  spreading.  Then  cut  back  the  outer  sides 
of  the  crack  with  a  small  cold  chisel  to  permit  inserting  a  considerable 
amoimt  of  rusting  compound,  being  careful  not  to  cut  away  any 
quantity  of  good  metal.  Then  fill  the 
crack  up  very  fully  and  carefully  with 
the  compound  consisting  of  two  parts  ir 
filings  and  one  part  sal-ammoniac.  Just 
enough  water  should  be  added  to  this  to 
make  a  paste  which  can  be  handled  better 
than  the  dust  or  powder.  After  inserting, 
let  the  cylinder  stand  for  a  day  or  two, 
and  if  it  does  not  seal  up  quickly  and 
entirely,  add  a  little  water.  If  this  does 
not  complete  the  job,  it  may  be  necessary 
to  go  over  it  again,  adding  more  of  the 
rusting  compound.  After  a  couple  of  tries, 
almost  any  skillful  repair  man  will  get  the  hang  of  this  job,  and  be 
able  to  seal  a  water  jacket  crack  perfectly  every  time. 

WeMing  Breaks  in  Cylinders.  Welding  is  used  ver>'  frequently 
now  on  cylinder  breaks,  probably  more  than  any  other  method,  since 
it  has  proved  to  be  quick,  accurate,  and  cheap.  It  has  ail  the 
desired  qualities,  which  cannot  be  said  of  any  other  process.  More- 
over, it  can  be  used  with  almost  any  form  of  metal,  which  also  cannot 
be  said  of  any  other  method.  A  separate  chapter  deals  with  welding, 
very  exhaustively.  It  is  recommended  that  every  repair  man  study 
it;  then  get  an  outfit  and  learn  to  use  it,  for  it  represents  a  source  of 
large  profit  when  its  use  is  once  mastered.  With  a  welding  outfit, 
the  method  of  procedure  is  often  the  reverse  of  other  processes.  Thus 
when  a  water  jacket  is  cracked,  the  first  operation  is  generally  the 


Flc.  34. 
SniUCi 


,r.^^ 


GASOLINE  AUTOMOBILKS 


cutting  away  of  sufficient  metal  to  enable  the  workman  to  see  the 
whuk-  extent  of  the  erack  and  also  to  permit  getting  at  all  the  surface 
with  the  welding  torch.  With  a  crack  of  small  size,  such  as  that  Just 
described,  cnougli  of  the  sides  should  be  cut  awa.\'  to  allow  working 
the  torch  in  between  them.  This  crack  should  be  gradually  refilled 
with  new  solid  metal,  melted  in  from  a  fuse  bar  or  melt  bar.  The 
sides  should  be  cut  awaj'  so  as  to  take  off  more  on  the  inside  if  possible, 
as  this  gives  the  new  metal  a  natural  hold  on  the  inside  in  addition  to 
the  fusing  together  of  the  old  and  new  metal. 

When  the  crack  is  larger,  but  still  not  a  big  one,  as  a  small  curved 
or  circular  shape,  say  2  inches  long,  a  formed  steel  plate  can  very  often 
be  cut  which  exactly  fits  around  and  over  tiie  crack.  This  is  then 
welded  into  place.  This  steel-plate  method  is  particularly  effective 
where  the  pieces  of  the  water  jacket  are  cracked  out  in  chipping  the 
hole  or  crack,  or  when  a.  single 
piece  to  be  welded  is  broken 
into  two  or  three  pieces  dur- 
ing the  chipping.  Another 
similar  water  jacket  crack 
repair  is  that  necessary  when 
■ylinder  water 


GASOUNE  AUTOMOBILES 


45 


Another  cylinder  weld  frequently  met  is  a  flan^  cracked  around 
a  holding  bolt.  In  such  a  break  the  fracture  is  usually  confined  to  the 
flange,  no  part  of  the  cylinder  wall  being  broken  or  cracked.  Thus, 
all  the  repair  work  is  external,  and  proceeds  more  easil>'  and  quickly 
than  would  be  the  case  when  dealing  with  the  more  accurate  cylinder 
wall.  This  is  a  simple  repair,  and  is  performed  entirely  from  the 
outside  by  cutting  the  crack  away  on  both  sides  to  allow  new  metal 
to  be  added  without  increasing  the  thickness,  then  setting  the  piece 


id  ol  Rc-A»enibLing 


carefully  in  place,  damping  it  there  and  fusing  new  metal  from  a  melt- 
bar  into  the  V-slot  formed  by  chipping.  In  case  the  crack  does  extend 
to  the  cylinder  walls  or  bore,  it  is  advisable  to  stop  the  weld  about 
iSr  inch  from  the  interior  surface  of  tlie  Ixtre.  In  this  weld,  as  in 
previous  ones,  excess  metal  is  left  on  the  outside;  in  fact,  this  is  done 
whenever  and  wherever  possible,  as  the  excess  metal  compensates 
for  the  somewhat  brittle  character  of  the  weld  and  guards  against  a 
recurrence  of  the  trouble  by  making  tlie  break  stronger  than  it  was 
iu  the  first  place. 


46  GASOLINE  AUTOMOBILES 

Working  in  Valve  Cages.  In  overhead  valve  engines,  when  the 
valves  are  set  in  removable  cages,  it  is  often  necessary  to  put  in  a  new 
cage.  This  is  worked  in  or  seated  in  the  cylinder  by  grinding  it  down 
to  a  perfect  seat  the  same  as  a  valve.  Oil  and  emery  are  placed  on 
the  seat  in  the  cylinder,  the  cage  set  in  place  and  gradually  worked 
around  and  down,  until  a  perfect  surface  is  obtained.  The  same  is 
applied  to  renewing  the  seat  when  a  valve  cage  shows  signs  of  leakage. 
Replacing  Pistons  in  Cylinders.  When  cylinders  or  pistons 
have  been  removed  to  be  worked  on,  replacing  these  is  a  difficult  job. 
There  are  two  ways  of  doing  tliis:  viz,  by  a  special  form  of  ring  closer, 
and  by  hand,  usin^  a  string.  The  former  is  a  shaped  device  which 
is  clamped  around  the  ring  and  squeezed 
together  with  pliers,  using  one  hand,  while 
with  the  otlier  hand  the  ring  is  guided 
into  the  groove.  The  secxjnd  and  more 
usual  method  is  illustrated  in  Fig.  36,  and 
requires  two  men,  unless  the  cylinder  is 
of  such  a  shape  that  it  can  be  clamped 
in  a  vise.  As  the  picture  brings  out, 
one  man  holds  the  cylinder  while  the 
?r  forces  the  piston  carry 


GASOLINE  AUTOMOBILES 


47 


TAPfR 


and  is  flanged  over  at  the  top  to  give  it  extra  stiffness  and  prevent 
its  entering  the  cylinder.  It  is  tnade  a  little  bit  small  for  the  size  of 
the  pistons  over  which  it  is  to  be  used,  so  it  will  have  to  be  sprung 
into  place.  When  this  is  done,  it  will  have  a  tight  hold  on  the  rings, 
compressing  them  so  they  will  enter  the  cylinder.  In  applying  it, 
care  should  be  used  to  put  it  on  squarely,  and  similarly  in  pushing  it 
down  by  forcing  the  piston  upward  into  the  cylinder,  as  it  should  not 
be  moved  off  of  a  ring  until  that  ring  has  been  entered  in  the  cylinder 
enough  so  it  is  held  therein.  That  is,  the  spring  clamp  should  not  be 
moved  down  below  a  ring  until  that  ring  is  engaged  and  held  within 
the  cylinder.  Its  use  is  restricted  to  one  size  of  motor,  which  is  no 
hardship  in  a  big  shop  where  one  make  of  car  is  handled  exclusively. 
The  small  shop  handling  a  variety  of  work  would  find  half  a 
dozen  different  sizes  useful  and 
economical.  Moreover,  the  cost 
of  this  device  is  very  small. 

A  modification  of  the  above 
device  consists  of  a  similar  small- 
size  band  of  sheet  metal,  made 
very  w  ide,  but  without  the  upper 
flange.  It  is  made,  however,  with 
a  pair  of  right-angle  lips  where  the 
two  sides  meet,  these  are  drilled 
for  a  clamping  bolt.  This  bolt 
has  a  wing  nut  with  clamping  rings  to  compress  the  lips.  Another 
modification  of  the  above  is  a  loop  or  strap  of  narrow  sheet  metal 
having  an  additional  loop  to  go  over  the  two  ends.  These  ends 
are  made  with  a  right-angle  bend  close  to  the  piston-curve  portion, 
and  the  compression  of  the  rings  is  effected  by  pressing  the  sides  of 
the  clamp  tightly  against  them,  then  sliding  the  small  loop  along  the 
ends  to  hold  this  tightness. 

Rigging  for  Replacing  Piston.  In  motors  of  the  detachable-head 
type,  like  the  Willys,  the  Chalmers,  the  Briscoe,  and  others,  the 
work  of  replacing  the  pistons,  particularly  if  the  crankcase  is 
cast  integrally  with  the  cylinder  block,  is  considerable.  In  fact,  it 
is  sufficiently  difficult  to  warrant  making  a  special  jig  for  guiding  the 
pistons  down  into  the  long  cylinder  bores;  this  fastens  onto  the  top 
of  the  cylinder  where  the  head  belongs. 


Fig.  38 


A  Simple  and  Easily  Made  Jig  for 
Pii 


Replacing  Pistona  in  Detachable 
Head  Motors 


48  GASOLINE  AUTOMOBILES 

As  shown  in  the  sketch,  Fig.  38,  the  jig  consists  of  a  round  shell, 
the  interior  of  wliich  is  at  tlie  bottom  of  the  same  bore  as  the  cyl- 
iniier,  but  flares  out  considerably  at  the  top.  The  base  consists  of 
the  flanKe  needed  for  turning  this  in  the  lathe  and  may  be  of  an\ 
shape,  size,  and  thickness.  The  action  of  the  enlarged  diameter  at 
the  top,  gradually  tapering  to  the  exact  cylinder  size  at  the  bottom, 
is  to  hold  the  piston  rings  in  place  and  slowly  contract  them  as  the 
piston  is  lowered,  so  they  pass  down  into  the  cyUnder  bore  without 
trouble.  One  casting  must  be  made  for  each  cjlinder  bore,  but  the 
time  and  trouble  which  they  save,  and  the  injuries  to  workmen  and 
parts  which  they  avoid,  make  them  well  worth  while. 

PISTONS  AND  ACCESSORIES 

Piston  Construction.  The  pistons  of  automobile  motors  have  long 
been  made  of  oast  iron,  with  the  piston  pin  held  In  bosses  on  the  piston 
walls.  For  all  onlinary  service  this  construction,  well  carried  out, 
serves  every  purpose,  but  with  the  development  of  very  high-speed 
motors,  with  piston  speeds  twice  and  three  times  as  high  as  past 
practice  has  sanctioned,  there  is  a  growing  tendency  to  substitute  steel 
for  cast  iron  in  this  imjiortant  reciprocating  element. 

Particularly  in  a\  iitti<m  motors  has  this  been  the  case;  the  pistons 


GASOUNE  AUTOMOBILES 


49 


done  with  new  fonm.  The  lightening  of  piston  weight  has  not 
materially  changed  the  old  open-end  trunk  form,  although  the  use 
of  aluminum  bas  modified  its  straight  shape  somewhat  in  the  hour- 
glass and  similar  forms.    Attempts  to  utilize  so-caUed  free  pistons, 


Fif.  39.    Old  and  Nfw  Typt«  of  PutQU 

Former  Hnvy  Pigton  M  Left;   Prcwnt  Lighter  Type  at  Richt 

Cnrlrry  iif  Lotomobile  Campaitg  of  Amiriea.  BrUitporl.  Coniiaefuiil 

in  which  the  upper  part  is  flexibly  connected  to  the  lower,  and  the 
use  of  combinations  of  pressed  steel  and  other  metab  have  done 
much  to  modify  the  general  form. 

Both  these  tendencies  are  well  shown  in  the  illustrations,  Figs. 
H9  and  40.  The  former  shows  how  a.  certain  piston  was  lightened  by 
taking  out  two  rings  at  the  top,  one  rib  inside,  and  generally  using 
thinner  metal.  The  old  form  is  shown  at  the  left,  the  new  at  the 
right.  The  other  tendency  is  seen  in  Fig.  40 
which  is  an  atutninum  alloy.  Note  how  this 
is  cast  to  have  less  metal  at  the  piston  boss 
and  also  to  be  strong  without  extra  ribs. 

Characteristics  of  Piston  Rings.  Cast 
iron  for  piston  rings,  long  used  to  the  exclu- 
sion of  everj'thing  else,  is  in  slight  degree 
yielding  its  pre-eminence  for  this  purpose 
also.  This  is  because  it  has  been  found,  in 
aviation  motors  with  steel  cylinders,  that 
bronze  affords  greater  durability  and 
smoother  running  against  the  steel-cylinder 
wall,  for  which  reason  bronze  rings — with  steel  or  cast-iron  springs, 
or  "bull  rings",  behind  them — have  been  found  most  advantageous. 
Multiple  rings,  three  or  more  in  a  groove,  are  finding  favor.  Theic 
thinnesa  necessitates  the  use  of  steel. 


GASOLINE  AUTOMOBILES 


GASOLINE  AUTOMOBlLt>^  51 

Types  of  Piston  Rings.  Where  formerly  three  or  four  plain  rings 
were  used,  each  one  filling  a  groove,  many  pistons  are  now  equipped 
with  multiple  rings  of  various  patented  forms,  for  which  many 
advantages  are  claimed.  Some  idea  of  the  variety  of  these  may  be 
obtained  from  Fig.  41  which  shows  a  number  of  different  forms. 

Thus,  A  indicates  a  ring  with  a  double  form,  yet  really  it  is  one 
continuous  piece,  cut  so  as  to  appear  as  two.  It  is  difficult  to  see  any 
advantage  in  this,  while  it  is  much  more  expensive  than  the  old- 
fashioned  form.  At  B  is  seen  a  type  which  has  an  outer  thin  but 
high  ring  within  an  L-shaped  inner  form,  both  with  plain  vertical  slots, 
and  without  holding  pins  of  any  kind.  A  somewhat  similar  form  is 
seen  at  C,  but  with  this  difference,  the  inner  ring  has  two  steps 
instead  of  one,  both  have  diagonal  slots,  and  a  pin  keeps  the  outer  one 
from  turning. 

The  form  at  D  has  a  pair  of  thin  and  very  flexible  high  rings,  set 
one  within  the  other.  They  are  concentric,  and  both  have  stepped 
joints.  The  extreme  flexibility  would  appear  to  take  all  the  value  out 
of  their  use  as  compared  with  the  ordinary  form.  Another  seen  at  K 
differs  in  that  one  part  is  placed  above  the  other  and  hekl  from  rotat- 
ing by  a  pin.  Both  have  diagonal  joints.  Both  are  eccentric  and 
the  pins  hold  them  so  the  slots  are  9()  degrees  apart.  In  the  form  at  /', 
there  are  three  pieces,  including  an  inner  one  of  full  height  with  a  deep 
outer  slot,  a  modified  U.  The  two  outer  parts  are  L-shaped  and  the 
L-projections  fit  into  the  slot  of  the  big  ring.  All  have  diagonal  slots 
and  are  pinned  in  place. 

An  eccentric  form,  whidi  has  a  tongue-and-groove  arrangement  at 
the  open  or  thin  end,  is  showii  at  G,  The  makers  call  this  the  lock 
joint.  PracticaJly  the  same  effect  is  produced  in  the  form  shown  at  //, 
except  that  the  opening  is  closed  by  a  separate  piece.  This  is  caller! 
a  guard,  and  it  is  machined  to  fit  under  one  portion  of  the  master  ring 
and  on  either  aide  of  the  slender  ends,  so  that  it  makes  up  the  full 
width.    This  use  of  the  old-fashioned  simple  ring  seems  griod. 

The  form  at  /  is  that  of  B  reversed,  that  is,  the  small  square  ring 
is  placed  on  the  inside  of  the  L-shaperi  ring,  and  has,  in  addition,  a 
horizontal  step  joint,  while  the  outer  member  has  a  vertical  step  joint. 
An  entirely  different  prindpie  is  utilized  in  the  form  at  J,  the  inner 
L-shaped  member  having  a  taper,  and  the  outer  thin  but  high  mem- 
ber havini^  a  con^eaponding  taper  to  fit  ag^unst  it.    The  idea  of  the 


52  GASOLINE  AUTOMOBILES 

taper  is  that  the  spring  of  the  two  rings,  slightly  opposed,  will  work 
through  this  to  hold  both  against  the  cyllmier  walb.  The  outside 
of  the  inner  ring  is  knurled  to  hold  the  outer  one  fham  rotating.  Both 
have  diagonally  cut  slots. 

In  the  form  shown  at  A',  there  are  three  parts,  divided  vertically, 
but  in  such  a  waj'  that  the  top  and  bottom  are  really  dependent  upon 
the  middle  to  hold  them  in  place  both  vertically  and  horizontally. 
It  is  difficult  to  see  greater  merit  in  this  form  than  of  three  plain  rings. 
The  form  at  L  is  somewhat  like  that  at  F,  except  that  the  inner  full- 
height  ring  has  a  pair  of  projecting  ridges  in  place  of  the  single  central 
slot.  Each  of  the  small  half-width  outer  rings  has  a  central  slot,  or 
groove,  and  end  ridges  to  fit  around  this.  Like  F,  this  has  the  small 
outer  rings  pinned,  but  differing  from  it,  all  have  diagonal  slots. 

In  the  form  seen  at  M,  three  parts  are  used,  but  the  center  full- 
height  piece  has  its  outer  surface  in  the  form  of  a  double  taper,  upon 
each  half  of  which  one  of  the  small  half-height  outer  rings  of  triangular 
cross-section  rests.  In  that  shown  at  N,  the  ring  is  a  continuous 
spiral,  being  somewhat  similar  to  A  in  this  respect.  Its  cut,  however, 
is  upon  a  slope  all  the  way,  so  that  its  thickness  varies  continuously. 
It  is  made  of  heat-t reatrd  steel.     It  is  difficult  to  see  how  the  vertical 


GASOLraE  AUTOMOBILES 


Piston  and  Ring  Troubles  and  Repairs 

Removal  and  Replacement  of  Pistons.  Speaking  of  pistons, 
there  are  several  things  that  the  beginner  should  leam  about  their 
removal  and  replacement.  While  it  is  not  a  dlflficult  matter  to  puU 
a  piston  out  of  a  c\'linder,  when  both  have  been  previously  lubricated, 
and  all  proper  precautions  taken  to  loosen  connecting  parts,  there 
are  a  few  important  things  to  remember.. 

The  piston  should  be  drawn  out  as  nearly  parallel  to  the  axis 
of  the  c>'linder  as  is  possible,  accompanied  by  a  twisting  motion  not 
unlike  taking  out  a  screw,  in  case  it  sticks  a  little.     If  ttie  piston 


sticks  badly,  pour  in  a  little  kerosene  and  work  the  piston  in  and  out 
3o  as  to  distribute  the  kerosene  between  the  two  surfaces. 

To  get  at  the  spaces  the  rings  must  be  removed,  and  as  they 
are  of  cast  iron  and  very  brittle,  this  is  a  delicate  task.  Two 
methfxls  of  accomplishing  this  are  illustrated  in  Fig.  42.  If  the 
owner  has  a  pair  of  ring-expanding  pliers,  the  rings  can  easily  be 
expanded  enough  to  Hft  them  over  the  edge,  as  shown  in  (a).  As 
very  few  owners  possess  this  useful  tool,  however,  a  more  common 
way  is  shown  in  (fc).    Secure  a  number  of  thin,  flat  steeb  aboi 


54 


GASOLINE  AUTOMOBILES 


3  inch  wide  and  ^  inch  thick- — ^corsetsteels,  flat  springs,  or  hack-saw 
blades  may  be  used,  although  the  latter  require  more  care  on  account 
of  the  teeth  along  one  edge.     The  length  of  these  steels  should  be 


such  as  to  reach  from  about  an  inch  below  the  last  ring,  to  the  top. 
Lift  out  one  side  of  the  ring  with  a  small  pointed  tool  and  slip  one 
of  the  steels  between  the  ring  and  the  piston,  then  move  around 
about  one-third  of  the  waj'  and  insert  another,  taking  care  to  hold 
the  first  in  place;  repeat  the  opera- 
tion with  a  third  steel.  When  these 
are  in  place,  the  sleets  will  hold  the 


GASOLINE  AUTOMOBILES  56 

one  until  it  gives  suddenly  and  is  then  spread  beyond  the  resisting  abil- 
ity of  the  iron.  It  is  applicable  to  all  forms  of  rings,  except  those  with 
diagonal  slots.  In  addition  to  the  construction  shown,  it  is  de^rable 
to  fit  a  spring  which  will  draw  the  handles  together  when  not  in  use. 
This  closes  the  jaws  and  keeps  them  closed,  ready  for  immediate  use. 

An  even  better  and  more  simple  form,  but  without  the  safety  feat- 
ure of  that  just  mentioned,  consists  of  a  large  diameter  steel  spring, 
shaped  not  unlike  a  very  big  piston  ring,  which  has  a  pair  of  handles 
fitted  to  the  ends.  This  is  shown  in  Fig.  44,  which  indicates  how 
the  nubs  on  the  two  handles  are  shaped  so  as  to  take  hold  of  stepped 
joint  rings.  By  making  these  nubs  differently,  any  form  of  ring  can 
be  handled.     A  device  of  this  sort  saves  the  repair  man  lots  of  time. 

Loosening  Seized  Pistons.  When  the  pistons  and  rings  freeze 
into  the  cylinder,  or  seize  because  of  a  lack  of  lubricant,  there  is 
nothing  quite  so  good  nor  quite  so  quick  acting  as  kerosene.  The 
cylinder  head  should  be  opened  as  quickly  as  possible,  and  the 
kerosene  poured  in  liberally  on  top  of  the  pistons.  This  should  be 
done  in  each  cylinder.  Kerosene  is  thin  and  will  work  down  between 
cylinder  wall  and  piston  rings,  gradually  cut- 
ting away  the  two  where  they  have  frozen 
together.  If  kerosene  is  not  available,  take 
the  thinnest  lubricant  at  hand;  heat  it  so  that 
it  will  be  still  thinner  and  more  penetrating. 


FW.  4fi.     Bmpk  Polon-I^  PulHni  Outfit  F1>.  M.     Pirton  Riu  Fuller 

Vbirb  AUon  lor  eS.  of  Pin 

then  pour  it  in.    At  times,  olive  oil  can  he  combined  with  kerosene 
to  advantage. 

Freeing  Wrist  Pins  and  Bushli^s.  When  the  piston  pin  or 
wrist  pin  is  inserted  directly  in  the  piston,  it  is  usually  a  light  fit, 
80  tight,  sometimes,  that  the  repair  man  experiences  difficulty  in 
gettii^  it  out.    To  overcome  this  difficulty,  a  piston  pin  puller  is 


66 


GASOLINE  AUTOMOBILES 


needed.  One  of  these,  shown  in  Fiff.  45,  is  made  from  a  piece  of  steel, 
a  steel  strap,  and  a  large  cap-screw.  This  piece  of  steel  is  drilled  and 
tapped  for  the  cap  screw,  and  for  the  bolts  to  hold  the  steel  strap. 
Then  the  latter  is  fastened  so  as  to  be  about  I  inch  larger  in  diameter 
than  the  piston,  or  still  larger  if  a  long  cap  screw  is  available.  When  a 
pin  is  to  be  removed,  the  strap  is  put  around  the  piston  and  the  cap 
screw  screwed  in  until  it  bears  against  the  end  of  the  pin.  This  can 
be  done  by  hand.  Then  a  wrench  is  applied,  and  as  the  screw  is 
forced  in,  the  pin  is  forced  out  on  the  opposite  side.  Be  careful  to  see 
that  the  far  side  of  the  steel  band  is  below  the  piston  pin  hole,  so  the 
pin  will  be  able  to  come  out  without  touching  it. 

This  can  be  simplified  b^  haMng  an  entlless  steel  band  with  a 
nut  on  the  mside  of  it  to  form  a  bacJting  for  the  cap  screw  to  work 
against,  or,  the  steel  band  can 
he  welded  to  the  nut. 

A  form  which  removes 
the  above  difficulty  is  that 
shown  m  Fig,  46,  This  is 
made  so  that  it  holds  around 
the  piston  at  two  points, 
jibo\e  and  below  the  piston 


GASOLINE  AUTOMOBILES 


57 


this  t\'pe  is  that  the  nut  shown  on  the  right,  which  is  operated  to 
force  the  bushing  out,  must  rest  against  the  surface  of  the  piston 
while  being  turned  around.  If  a  small  U-bar  be  made  to  rest  against 
the  piston  side,  with  a  central  drilled  bole  through  which>the  threaded 
end  passes,  the  nut  will  bear  against  the  outside  surface  of  this,  so 
that  even  if  the  nut  should  scratch,  no  harm  will  be  done  to  the  piston. 
These  pullers  are  used  as  substitutes  for  nn  arbor  press,  but  this  is 
desirable,  as  the  use  of  the  press  is  likely  to  distort  the  more  or  less 
delicate  piston.  With  aluminum  and  the  lighter  weight  cast-iroa 
pistons,  this  is  a  thing  which  it  is  desirable  to  avoid. 

Some  motors  have  the  wrist  pin  locked  in  place  by  means  of  an 
expanding  nut  with  a  sunken  square  hole  for  turning.  To  start  these, 
a  vTench  with  a  square  projection  or  tit  to  fit  this  is  needed.  Such 
a  ATench  is  used  on  certain  lathe  chucks,  so  one  can  alwa>'s  be  bor- 
rowed in  a  machine  shop  or  tool  room. 

Mandrel  for  Tumii^  Pins.  Because  of  its  being  hollow  in 
many  cases,  the  wrist  pin  is  difficult  to  handle  when  any  work  must 
be  done  upon  it.  For  this 
purpose,  a  mandrel  is  needed. 
The  method  of  constructing 
and  using  this  is  shown  in 
Fig.  48.  This  consists  of  a 
shaft  with  a  taper  at  one 
end  and  thread  at  the  other, 
for  a  tapered  nut.  The  wrist 
pin  is  slipped  on  the  outer 
end,  the  taper  nut  put  in 
place  against  it,  and  the 
backing  nut  put  on  behind  that.  Then  these  are  screwed  up  until 
the  two  tapers  hold  the  pin  firmly,  after  which  it  may  be  placed  in 
the  latbe  and  work  done  upon  it. 

Speeding  Up  Old  Engines  by  Lightening  Pistons,  Etc  As  has 
been  pointed  out  previously  under  "Cams",  one  way  to  speed  up  an 
old  engine  is  to  replace  the  old  camshaft  and  cams  with  new  ones 
giving  more  mfxlem  timing.  Another  and  a  less  expensive  and 
troublesome  way  in  which  this  can  be  done  is  by  lightening  the 
pistons  and  the  reciprocating  parts.  This  the  repair  man  will  surely 
be  called  upon  to  do,  as  the  manufacturer  probably  would  refuse 


58 


GASOLINE   AUTOMOBILES 


In  order  to  get  out  any  amount  of  metal  worth  the  trouble,  it 
will  be  necessary  to  drill  from  12  to  20  or  more  holes  of  from  J-inch  up 
to  1-inch  diameter,  depending  ujjon  the  size  of  the  piston  as  to  bore 
and  length.  In  a  sbc-cy  tinder  motor,  i 
thif>  amounts  to  almost  100  holes 
(e\en  more  in  some  cases),  and  as 
these  must  be  drilled  with  consid-  | 
trable  similarity  in  thepisttjns,  itis 
ttcU  wortli  while  to  construct  a  fix- 
ture to  aid  or  speed  up  this  work. 

One  idea  of  the  way  such  a 
lightened  piston  should  look  when 
finished  is  given  in  Fig.  49,  which 
shows  the  steel  pistons  used  in  the    I 
Sunbeam  racers.     These  are  made   i 
this  way  to  give  the  maximum  qf 
lightness  with  strength.     Although 
made  from  steel,  this  is  done 
.simply  to  get  very  light  side 
i,  and  the  general  appear- 
ance  of   the  skirt   with   its 


GASOLINE  AUTOMOBILES  53 

very  well.  To  one  of  the  uprights  is  pivoted  a  long  handle,  having 
a  lined  V  which  matches  with  that  of  the  upright  helow  it,  and  ^ves 
a  good  grip  on  the  piston. 

Drilling  Holes.  When  drilling  to  save  weight,  the  holes  are 
put  in  close  together  and  in  regular  form,  the  idea  being  to  take  out 
as  much  weight  of  metal  as  is  safe.  In  doing  this,  it  is  well  to  work 
out  a  scheme  of  drilling  in  advance,  to  make  a  heavy  brown  paper 
template,  and  fasten  this  to  each  piston  in  turn.  It  is-not  advisable 
to  remove  all  the  metal  possible  at  first,  but  only  enough  to  show  the 
benefit  of  the  method;  after  it  has  proved  satisfactory,  the  first  job 
may  be  improved  upon  later.  For  instance,  In  lightening  pistons, 
it  is  a  good  plan  to  use  a  j-inch  drill  the  first  time,  and  not  to  put  in 
too  many  holes.  If  this  proves  satisfactory,  and  the  owner  comes 
back  for  more,  you  can  go  over  the  same  lot  of  pistons,  using  a  i-lnch 
or  f-inch  drill  between  the  existing  holes,  and  thus  reduce  the  weight 
of  the  lower  end  of  the  piston  to  its  lowest  possible  point. 

Testing  Size  of  New  Piston.  A  skilled  repair  man  gives  the 
following  suggestion  relative  to  trying  new  pistons  for  clearance: 
When  not  certain  whether  the  new  piston  will  give  sufficient  clearance, 
heat  it  to  about  600°  F.  If  it  is  a  snug  fit  in  the  cylinder,  it  probabh- 
will  give  satisfaction  under  normal  running  conditions.  This,  of 
course,  is  only  approximate  as  the  cylinder  would  heat  up  in  use  and 
expand  but  it  serves  the  purpose  and  is  quickly  and  easily  done. 

Non-Leaking  Rings.  Another  repair  man  says  that  when  the 
rings  get  old,  they  can  be  made  compression  proof  by  grindjng  down 
so  that  two  old  ones  will  occupy  the  space  formerly  taken  by  one. 
This  would  work  well  for  the  top  groove  with  a  new  ring  lower  down. 

Sometimes  a  ring  will  get  broken  when  no  others,  either  old  or 
new,  are  obtainable.  In  such  a  case,  the  ring  can  be  welded,  if  unusual 
care  is  exercised  not  to  melt  away  any  of  the  metal. 

When  rings  must  be  turned  in  the  lathe,  either  for  reilucing  the 
thickness  or  for  truing  up  the  face,  a  wooden  face  plate  should  be  made 
with  a  slightly  tapered  groove  for  the  ring  to  fit  into.  The  ring 
should  be  pressed  into  the  groove,  and  its  natural  spring  will  hold  it  in 
place.  When  working  on  the  outer  diameter,  the  face  of  the  wood 
will  have  to  be  cut  away  sufficiently  to  allow  the  ring  to  project,  or, 
instead  of  a  angle  large  central  hole,  an  annular  ring  can  be  turned  in 
the  wooden  face  plate,  the  ring  being  fitted  over  the  outside  of  it. 


GASOLINE  AUTOMOBILES 


Tracing  a  Ring  Knock.  Many  times  there  is  an  elusive  light 
-  knocltiiig  or  cliattering  in  the  motor,  especially  at  low  speeds,  which 
cannot  be  run  down.  This  is  often  due  to  piston  rings  wearing  at  the 
top  and  bottom  so  they  are  loose  in  their  grooves.  When  the  piston 
moves  upward,  these  rings  remain  stationary  until  they-  strike  the 
bottoms  of  their  grooves;  when  it  moves  downward,  the  rings  strike 
the  tops  of  the  grooves.  At  low  speeds,  these  noises  can  be  distinctly 
heard;  but  at  higher  speeds,  they  are  so  fftint  that  they  blend  off  into 
the  general  murmur  of  the  engine.  Another  noise,  which  comes  from 
the  rings,  is  that  due  to  weakness  or  loss  of  spring.  This  is  shown  by 
a  sharp  rapping  somewhat  like  a  piston  slap,  when  the  throttle  is 
opened  suddenly.  If  the  rings,  and  especially  the  top  ring,  are  not 
stiff  enough  to  resist  the  compression  and  explosion,  this  force  will 
compress  them.  At  the  end  of  the  stroke, 
they  will  expand  suddenly  against  the 
cylinder  wall,  causing  the  rapping 
described,  A  notch  filed  in  one  edge  so 
the  pressure  can  leak  in  behind  the  ring 
will  help  matters,  although  new  rings  are 
better. 

Curing  Excessive  Lubrication.    Uolc! 


GASOLINE  AUTOMOBILES 


61 


removes  the  oil  from  the  cylinder  walb  into  the  groove*  whence  it 
passes  through  the  holes  to  the  piston  interior  and  there  drops  back 
into  the  crankcase.  No  ring  is  placed  in  the  slot  as  it  would  prevent 
the  free  passage  of  the  oil.    Thisdevicestops  the  smoking  immediately. 

Loose  Piabms.  Many  times  the  pistons  will  wear  just  enough  so 
that  they  are  loose  in  the  cylinder  all  the  way  around.  This  causes 
leakage  of  gas,  piston  slaps,  and  other  similar  troubles.  If  the  owner 
of  the  car  does  not  care  to  buy  new  pistons,  or  if  the  car  is  an 
"orphan",  or  if,  for  other  reasons,  pistons  cannot  be  obtained,  the 
clever  repair  man  can  remedy  the  trouble  at  small  expense.  The 
process  consists  in  heating  and  expanding  the  old  pistons.  The 
heating  is  done  in  charcoal  and  must  he  done  very  carefully  and 
slowly.  After  the  pistons  become  red  hot  the  fire  is  allowed  to  go  out 
slowly,  so  that  the  piston  is 
cooled  in  its  charcoal  bed. 
Sometimes  as  much  as  n^ 
of  an  inch  can  be  gained  in 
this  way.  WTien  the  pistons 
are  so  far  gone  that  they 
cannot  be  handled  in  this 
way,  they  must  be  replaced 
With  new  ones. 

Mounting  Pistons  on  Lathes.  It  is  difficult  to  handle  a  piston 
in  the  lathe,  or  machine  the  outside  in  any  manner,  as  a  chuck  does 
not  get  enough  of  a  hold  on  it,  and  is  likely  to  mark  the  surface. 
\Vben  work  on  it  is  necessarj-,  the  piston  can  be  handled  effectively 
by  using  a  small  rod  with  an  eye  at  one  end.  This  is  made  to  fit  the 
piston  pin  in  the  case  of  an  old  piston.  The  rod  is  run  through  the 
hollow  spindle  and  bolted  at  the  outer  end.  The  tightening  of  the  nut 
on  it  pulls  the  piston  up  against  the  face  plate  as  Fig.  52  shows. 
This  same  method  can  be  used  when  making  a  new  piston.  In  the 
latter  case,  it  is  held  in  the  chuck  to  finish  the  outside  and  inside,  then 
the  wrist-pin  hole  is  drilled,  bored,  and  reamed,  and  the  wrist  pinfitted. 
Finally,  the  finishing  cut,  or  grinding  of  the  outside,  is  completed. 


^prff: 


CONNECTINQ   RODS 
Des%a  Oiaiacteiisttes.    IlSedion  Form.     Established  prac- 
tice in  Qonnecling-rod  design  is  almost  alt  in  favor  of  the  ^qjmon 


GASULINE   AUTOMOBILES 


H-section  rod,  usually  with  two  bolts  to  attach  the  cap.  In  some 
cases  four  bolts  are  used,  since  with  four  bolts  a  flaw  or  crack  in  one 
is  less  likely  to  cause  damage  than  is  the  case  when  only  two  are  use<I. 
The  old  scheme  of  hinging  the  cap  at  one  side  is  now  practically 
obsolete,  having  been  discarded  because  it  made  accurate  adjustment 
of  the  bearing  surfaces  almost  impossible. 

Tendency  to  Lighten  Rods.  The  modern  tendency  toward 
light<?ning  the  weight  has  extended  tn  the  connecting  rods,  since  a 
portion  of  the  rod  is  considered  as  reciprocating.  This  lightening 
has  been  accomplished  by 
external  machining.  Thus, 
in  the  tvpical  connecting  r*)d 
of  forged  alloy  steel,  shown  in 
Fig.  53,  the  format  the  left  is 
thatformerlyused,  while  that 
at  the  right  is  its  present 
shape.  Note  how  the  round- 
ing sides  of  the  H-part,  nec- 
essary in  forging,  have  been 
machined  off;  how  the  fillets 
at  big  end   and    piston  enil 


GASOLINE  AUTOMOBILES  63 

llie  question  of  cost,  bowever,  is  a  consideration,  since  it  is  necessary 
to  bore  the  hole  through  the  inside  of  the  rod,  whereas  a  forged  rod 
of  H-sectiou  requires  no  machining  except  at  the  end. 

The  wonderful  progress  in  welding,  however,  has  made  it  possible 
to  construct  a  tubular  connecting  rod  at  a  very  low  expense,  and,  owing 
to  its  many  advantages,  this  is  finding  much  favor  for  small  motors. 
The  two  ends  are  machined  and  a  section  of  tubing  welded  to  them. 

One  advantage  of  the  tubular  rod,  in  addition  to  its  superiority 
for  withstanding  the  compression  load  to  which  a  rod  is  chiefly  sub- 


ject, is  that  it  can  be  used  as  a  pipe  to  convey  oil  from  the  big  end 
to  the  piston-pin  bearing. 

Fig.  54  shows  an  example  of  a  very  light-weight,  high-quality, 
aviation-motor  connecting  rod,  machined  out  of  a  solid  bar  of 
alloy  steel,  and  provided  with  four  bolts  in  the  cap. 

Connectii^Rod  Bearings.  Usual  Types.  Connecting  rods  have 
two  different  forms  of  bearings.  This  is  due  to  the  difference  in  ^eir 
service.  At  the  upper  or  piston  end,  the  bearing  is  usually  a  high- 
grade  bronze  tubing,  machined  all  over  and  pressed  in  place.  When 
in  place,  it  generally  has  a  central  oil  hole  drilled  through  rod  and 
bushing,  and  then  a  couple  of  oil  grooves  are  scraped  in  by  hand  to 
start  from  this  hole  and  distribute  the  oU  outward  in  both  directions 
on  its  inner  surface. 


04 


GASOLINE  AUTOMOBILES 


At  the  lower  or,  as  it  is  usually  calletl,  big  end,  the  connecting  rod 
must  liave  a  better  bearing.  This  end  is  bolted  around  the  crankshaft 
pin  and  must  sustain  high  rubbing  speed,  as  well  as  the  load  of  explo 
sions.  Bolting  it  on,  and  the  need  for  removing  it  occasionally,  call 
for  a  form  which  is  split  horizontally.  Generally,  this  bearing  is  ot 
high-grafle  bronze  with  a  softer,  or  babbitt,  central  lining  which  can 
be  replaced  easily  and  quickly.     The  lianler  Itrorine  back  will  sustain 


GASOLINE  AUTOMOBILES 


65 


somewhat,  in  that  there  are  two  connecting-rod  big  ends  working 
upon  one  crank  pin,  that  is,  an  eight-cylinder  V-engine  uses  a  four- 
cylinder  form  of  crankshaft  with  two  connecting  rods  on  each  pin. 
This  modifies  what  was  good  connecting  rod  bearing  practice,  one  of 
two  different  forms  being  utilized.  When  the  rods  are  placed  side  by 
side  with  individual  bearings,  the  pins  are  made  very  large  and  as  long 
as  possible,  in  order  to  give  adequate  bearing  surface.  The  other 
form  is  the  forked  rod  in  which  one  rod  works  within  a  slot  in  the 
other.  In  this  t>T>e,  a  split  bearing  of  the  usual  form  is  placed  in  the 
forked  or  long  rod,  and  the  outer  surface  of  the  central  part  of  this 
prepared  as  a  pin  surface  for  the  other  or  central  rod.  The  requisite 
area  of  the  smaller  rod  bearing  is  made  up  by  its  larger  diameter. 
This  is  well  shown  in  Fig.  55,  where  the  rods  and  bearing  are  shown 
assembled,  and  the  separate  big-end  bearing  is  shown  at  the  rig^t. 
In  another  type  of  V-motor  connecting-rod  bearing,  the  larger  bearing 
is  slotted  for  the  central  rod  and  its  bearing,  the  slot  being  made  large 
enough  to  permit  a  rotation,  which  never  exceeds  a  quarter  of  a  turn. 
This  arrangement  is  more  complicated  to  install  and  repair  than  the 
form  shown. 


Connecting  Rod  Troubles  and  Repairs 

Qassification  of  Troubles.  In  general,  all  connecting-rod 
troubles  come  under  one  of  four  headings:  straight  rod,  proper  bear- 
ing adjustment,  mechanical  work  (scraping  bearings,  straightening  rod, 
or  other  work),  and  special  equipment  for  doing  connecting-rod  work. 

Stra^htening  Bent  Rod.  The  need  for  a  straight  and  true 
rod  is  apparent,  but  it  is  surprising  how  many  rods  are  not  straight, 
particularly  in  old  motors. 


Many  erratic  and  bad- 
sounding  motors,  have  all 
their  trouble  caused  by  a 
bent  rod.  A  connecting 
rod  can  be  bent  either  of 
two  ways,  and  one  gives  as  much  trouble  as  the  other.  If  bent  in 
the  plane  of  rotation,  the  rod  will  simply  be  shortened,  the  piston  will 
not  go  as  high  as  it  should,  and  it  will  go  down  a  little  lower  than 
nminal.  Moreover,  the  bend  will  press  it  with  imusual  force  on  the 
cylinder  wall  on  one  side  and  cause  it  to  wear  more  than  the  other. 


i?/-/ //  FressBedl'^ 


^ 


y^//^///y 


iU 


m 


Fig.  56.     Method  of  Teeting  Connecting  Rods 
with  Two  Mandrels 


GASOLINE  AUTOMOBILES 


The  combination  will  soon  result  in  trouble.  When  bent  in  a  longi- 
tudinal direction,  that  is,  fore  and  aft,  the  upper  end  of  the  rod  will 
run  against  one  side  of  the  piston  or  perhaps  only  knock  against  it 
on  each  stroke.    At  any  rate,  this  too,  wiU  give  trouble. 

Methods  of  Testing  Straigkttuss  qf  Rods.  The  first  thing  to  do 
when  a  connecting  rod  is  suspected  is  to  take  it  out  and  test  it.  One 
way  of  doing  this  is  to  attach  the  lower  end  to  a  mandrel,  which 
can  be  bolted  into  a  drill-press  table,  as  shown  in  Fig,  56.  Before 
doing  this,  the  small  end  is  also  fitted  with  a  mandrel,  the  lower  part 
of  which  is  of  considerable  length  and  has  two  short  vertical  pegs. 
When  the  big  end  is  bolted  down,  if  both  the  small  pegs  on  the  other 
end  touch.  It  proves  at  least  that  the  two  holes  (big  end  and  small 
end)  are  parallel.     If  one  of  these  pegs  is  off  the  table  as  shown. 


GASOLINE  AUTOMOBILES 


67 


Fig.  58.     Coimectinc;  -  Rod    ^tnu^tener  Cotwtmeited 
from  Threc^uArtcT-lDch  Bar  Stock 


is  that  it  always  works  the  same,  while  the  use  of  surface  gages 

and  calipers  varies  from  one  workman  to  another,  and  even  with  the 

same  man,  from  day  to  day,  according  to  his  moods  and  feelings. 

As  the  sketch  shows,  there  is  a  mandrel  for  each  end  of  the  rod,  that 

for  the  big  end  bang  jMvoted  in  the  fixture.    AMien  the  rod  is  forced 

into    this,    and    the    other 

mandrel  put  in  place  in  the 

pistcm  end,  if  rotated  down 

to  a  flat  position  (as  shown), 

the     small     end     mandrel 

should   touch  both   of  the 

fixture    stops.      If    badly 

twisted,  it  will  not  be  able 

to  go  down  on  one  side. 

Straighiening  Jigs. 
When  it  has  been  proved 
that  the  rod  is  not  straight,  it  is  necessary-  to  have  a  device  for  apfJy- 
Ing  pressure  in  order  to  straighten  it.  The  simplest  way  is  an  ordinary' 
straightening  press  consisting  of  a  pair  of  ways  ^ith  V-blocks  upon 
which  the  work  is  supported  and  a  lever  or  screw  to  apply  the  pressure 
in  the  middle.  The  work  is  supported  on  the  V-blocks,  the  distance 
apart  var^Tng  with  the  amount  it  is  to  be  bent — far  apart  for  a 
big  bend,  dose  tc^;ether 
for  a  small  one.  For  as 
short  a  member  as  a  con- 
necting rod,  howe\'er, 
this  is  not  sufficiently 
accurate,  and  be»des,the 
f  onn  of  the  rod  does  not 
suit  it  to  good  results  by 
this  method. 

A  mofie  fixture  for 
bending  a  rod,  diown  in 
Fig.  58,  consists  of  a  pair  of  hooks  for  holding  it  and  a  central 
screw  for  applying  power.  The  rod  is  slid  into  place  inside  the 
hocdcB  and  the  screw  turned  imtil  the  rod  is  straightened.  Then  to 
lari'gnt  its  qjfinging  back  when  the  pressure  is  released,  it  is  peened 
oo  the  side  cqiposite  the  screw.    Hie  advantage  of  this  method  is 


Fig.  SO.     Box  Type  of  ConueKrting-Kod  tHnicfateoer 


GASOLINE  AUTOMOBILES 


.\vs\vv.'.\'.k'.,',,v. 


that  it  throws  all  stresses  upon  the  nxi  itself  and  none  on  the  bear- 
ing surfaces.  The  hooks  are  forged  from  high-carbon  steel  of  f-inch 
square  section.  Tlie  screw  should  be  not 
less  than  f  inch  to  f  inch  in  diameter  and 
fine  threaded. 

Another  fixture  is  on  the  box  order, 
shown  in  Fig.  59.  This  has  a  pair  of  end 
clips  which  hold  the  rod  tight  by  means  of 
wedges  wliich  are  driven  into  place.  When 
this  has  been  done,  the  rod  is  straightened 
by  means  of  the  central  screw.  As  will  be 
noted,  the  principal  difTerence  between  the 
two  forms.  Figs.  .58  and  59,  is  in  the  holding 
method.  There  are  other  forms,  as  well  as 
forms  of  mandrels  for  lapping  in  big-ead 
bearings,  which  are  so  constructed  as  to  give 
a  check  on  straightness  and  to  allow  of 
remedying  the  situation  if  the  rod  is  not 
straight.  Some  of  these  will  be  described. 
Offsetting  Causes  Trouble.  Many  motors 
^  built  with  offset  connecting  rods,  that 


GASOLINE  AUTOMOBILES 


69 


a  rcx^ing  motion  of  the  pins  results,  and  this  causes  a  noise.  New 
bearings  help  tanporarily,  but  a  stiffer  connecting  rod  will  often 
roned y  it  more  or  less  permanently. 

Adjustment  of  Connecting-Rod  Bearings.  Babbitting  Bearings. 
As  has  been  stated,  the  majority  of  connecting-rod  and  crankshaft 
bearings  are  bronze  shells  or  backs,  lined  or  faced  with  babbitt  as  a 
wearing  metal.  The  bronze  provides  the  stiffness  and  long  life,  the 
babbitt,  the  softer  wearing  face  which  is  easily  and  cheaply  replaced. 
In  this  replacement,  a  form  or  jig  to  simulate  the  crankpin  and 
approximate  its  size  must  be  used  for  a  center.  A  form  made  of 
wood  is  shown  in  Fig.  61.  This  is  simply  a  round  member  of  hard 
wood,  turned  up  slightly  smaller  than  the  actual  crankpin  at  the 
upper  end,  while  the  lower  end  is  left  large  to  form  an  under  surface 
for  the  metal.  Next,  the  upper  part  is  split  or  rather  has  a  cut  taken 
across  it,  equal  in  thickness  to  the  shim  to  be  used  when  the  bearing  is 


Fig.  62.     Home-Made  Creeper 

assembled  in  place.  Then,  when  the  babbitt  is  poured  in,  a  metal 
member  is  set  across  the  rod  to  form  the  shim,  which  is  shown  in  the 
smaller  sketch  at  the  right. 

This  method  has  the  advantage  over  that  of  using  the  pin  when 
pouring  the  metal  in  position,  because  it  gives  a  Uttle  surplus  to 
machine  off,  and  thus  makes  the  surface  more  accurate  before  it  is 
scraped.  If  broaching  to  harden  the  surface  of  the  metal  is  resorted 
to,  it  gives  a  little  metal  to  broach  down.  Moreover,  by  making  it 
so  simple  and  easy  to  handle,  the  work  of  babbitting  is  made  easy. 
TTiis  cannot  be  said  of  tr>-ing  to  babbitt  in  place.  The  core  need  not 
necessarily  be  of  wood;  it  can  be  of  metal  or  of  an\^hing  else  desired. 
But  the  wood  has  the  advantage  of  being  easily  worked,  or  of  being 
dieap  and  quiddy  obtained. 

Kinks  in  Adjusting  Bearings,  L^sually,  crankshaft  and  connect- 
ingH!od  bearing  adjustment  is  a  difficult  job.     This  is  particularly 


TO  GASOUNE  AUTOMOBILES 

true  when  the  engine  is  not  removed  from  the  chassis.  The  con- 
necting-rod bolts  are  tight  and  hard  to  reach,  and  the  operator,  who 
is  lying  on  his  back,  has  all  dislodged  dirt  or  oil  dropping  in  his  face. 
Work  like  this  calls  for  an  easy  means  of  getting  under  the  engine  and 
out  again.  For  this,  a  form  of  creeper  is  necessary.  There  are  many 
forms  made  and  sold,  but  a  simple  one  which  any  repair  man  can 
construct  for  himself  is  shown  in  Fig,  62.  This  consists  of  a  wood 
frame  with  casters  at  the  four  corners  and  longitudinal  slats  for  the 
floor.  By  making  tJie  ends  concave,  the  surface  is  made  concave. 
With  a  pillow  or  other  head  rest,  it  is  more  comfortable  to  use. 
Another  way  in  which  this  work  may  be  facilitated  is  to  make  a 
special  socket  wrench  for  connecting-rod  nuts  and  to  make  it  deep 
enough  to  hold  four  nuts,  one 
JJjiiJft  over   the    other.     Then  with   a 

spring-stop  arrangement,  Fig.  63, 
the  nuts  from  two  rods  can  be 
taken  off  without  stopping;  or  if 
lock  nuts  are  used,  the  nuts  and 
lock  nuts  may  be  removed  from 


GASOLINS  AUTOMOBILES 


71 


wear,  and  .003  inch  for  severe  wear.     If  more  than  this  has  been 

worn  off  the  bearings,  they  need  re-scraping,  as  this  is  about  the 

.  maximum  that  can  be  taken  out  without  scraping.    Usually,  when 


the  bearings  have  been  taken  up  in  this  way,  the  caps  are  put  back 
on  pretty  tight,  a  little  bit  tighter  than  they  were  previously.  Then 
they  are  flooded  with  oil  and  run  in  this  condition.  The  combina- 
tion of  excess  oil  and  tight 
caps  soon  gives  the  entire  bear- 
ing surface  a  fine  polish  which 
will  last  for  many  miles. 

Special  Sleeve  Replaces 
Shims.  In  one  motor  (Reo), 
the  shim  is  replaced  by  an 
ingenious  arrangement  of  a 
threaded  sleeve  around  the 
bearing  bolts.  This  b  shown 
in  Fig.  64  in  which  the  sleeves 
are  marked  A  and  the  bolts 
B.  It  will  be  noted  that  the 
sleeves  rest  against  the  upper  part  of  the  bearing  and  have  a  head 
against  which  the  bolts  rest,  so  that  the  latter  can  be  tightened  only 
aa  far  as  the  sleeves  allow.  With  this  construction,  when  it  is  desired 
to  tighten  a  bearing,  the  socket  wrench  is  slid  on  so  as  to  hold  the 
heads  of  both  bolt  and  sleeve,  and  then  turned  to  unscrew  both. 


72  GASOUNE  AUTOMOSaES 

Then  the  socket  is  drawn  off  the  sleeve  head,  in  the  position  shown 
at  the  left,  and  the  bolt  sen-wed  back  to  pinch  the  bearing  together 
and  lock  it.  As  will  be  noted,  the  two  halves  of  the  bearing  metal 
are  separated  a  considerable  distance  so  that  this  arrangement  is 
good  for  many  thousand  miles.  Two  years"  running  will  usually 
exhaust  the  possibilities  of  the  original  bearing  and  its  shims,  which 
calls  for  re-babbitting,  re-scraping,  new  shims,  or  for  an  entirely  new 
bearing.  This  form  of  construction  could  be  used  anywhere  that 
the  bearings  are  likely  to  need  frequent  readjustment. 

Mandrel  for  Lapping.  In  order  to  give  the  connect ing-ro< I 
bearings  the  best  possible  surface,  a  mandrel  should  be  used  to  lap 
tliem  in.  This  is  the  equivalent  of  running  in.  The  rod,  with  bear- 
ings in  place,  is  put  on  the  mandrel,  and  the  bolts  tightened  a  little; 
then  it  is  worked  back  and  forth,  until  the  flattening  down  of  the 
surface  will  allow  more  tightening  of  the  bolts.  This  is  continued 
until,  with  a  mandrel  the  exact  size  of  the  erankpins,  the  bolts  can 
be  pulled  up  dead  tiglu.  Then  the  rod  is  removed ;  it  is  finished. 
Such  a  mandrel,  shown  in  Fig.  65,  is  usually  a  piece  of  steel  turned  up 
on  one  end  to  the  exact  size  of  the  crankpin.  with  a  flat  spot  machined 
in  the  other  end  to  allow  holding  in  the  vice.  By  making  it  perfectly 
straight,  a  try  sriuarc  against  the  mandrel  will  show  the  correctness 


GASOLINE  AUTOMOBILES 


7dr 


Variation  of  Design,  llie 
greatest  variations  in  auto- 
mobile crankshaft  design,  aside 
from  those  pennitted  or  made 
necessarj'  by  diflFerences  in  the 
quality  of  material,  are  due 
to  the  conditions  involved  in 
the  different  combinations  of 
cylinders  that  can  be  utilized. 
Thus  the  number  of  crank 
throws,  as  well  as  their  posi- 
tion, varies  with  the  type  of 
motor. 

As  the  repair  man  knows 
crankshafts  today,  they  are  of 
two  kinds.  The  first  is  the 
four-cvlinder  form,  in  which 
all  throws  are  in  a  single  plane. 
This  t^-pe  of  shaft  has  four 
pins,  one  for  each  connecting- 
rod  big-end  bearing.  It  may 
have  either  three  bearings,  as 
shown  in  Fig.  66,'  or  five  bear- 
ings. The  second  t>T>e,  which 
the  repair  man  is  likely  to 
meet,  is  the  six-cylinder  shaft, 
which  will  have  six  pins  for 
connecting  rods;  these  are 
grouped  in  pairs,  and  each  pair 

• 

m  a  different  plane,  the  angle 
between  them  being  120  de- 
grees. This  tj-pe  of  shaft  may 
have  either  four  or  seven  bear- 
ings. In  the  four-bearing 
form,  there  is  a  bearing  at  each 
end,  and  another  between  each 
pair  of  cylinders,  as  shown  in 
Fig.  67,  with  pistons  and  con- 


\ 

u 

1 


■5 


o 


<2 


tt. 

SI 


^1 

a 

•   o 

SO 


74 


GASOLINE  AUTOMOBILES 


Meeting  rods  attached.  In  the  seven-bearing  form,  there  is  a  bearinfC 
on  each  side  of  eaeh  connecting  rod.  These  are  the  modem  types, 
hut  older  shafts  miiy  be  encountered  occasionally,  in  the  way  of 
four-cylinder  shafts  with  two  bearings,  one  at  each  end  only;  also  with 


-ftRl^ 


C.,<iH,>y  •<!  .\','.li,tr  A  .Woi-mon  Company,  /nrfiaiupoii.,  IniiaHa 

four  hearings,  the  latter  having  the  usuaUenter  bearing  eliminated. 
Tlie  modern  tendency  is  towani  siniitUHciitioii,  compactness,  and  low- 
ered first  cost;  and  the  shafts  with  the  fewer  number  of  bearings  are 
on  the  increase. 


GASOLINE  AUTOMOBILES  75 

Eight-Q'linder  engines  generally  use  a  four-cylinder  form  of  shaft, 
with  two  connecting  rods  on  each  of  the  four  pins.  This  is  explained 
previously  under  connecting  rods.  Similarly,  twelve-cj-linder  motors 
have  a  typical  six-cylinder  crankshaft,  with  two  rods  on  each  of  the 
six  pins. 

Balanced  Crankshafts.  While  not  an  assembled  shaft  in  the 
sense  just  referred  to,  the  balanced  form  is  meeting  with  great  favor, 
and  is  being  widely  adopted.  This  will  be  met  by  the  repair  man 
in  two  forms.  One  is  like  Fig.  66,  except  that  the  weights  are 
machined  to  fit  on  the  crank  cheeks  and  bolted  there.  The  repair 
man  should  not  remove  these  unless  it  is  absolutely  necessary,  as 
they  vary  in  size  and  weight.  They  are  fitted  in  place  with  extreme 
care  and  fastened  extremely  well.  The  other  type — the  kind  being 
introduced  into  the  latest  models — has  its  counterweights  forged  as  a 
part  of  the  crankshaft.  Fig.  68.  In  this  type,  the  weights  are  adjusted 
to  make  the  proper  balance  when  the  shaft  is  being  machined. 

Oankshaft  Bearings.  The  bearings  of  the  crankshaft  in  the 
crankcase  do  not  differ  materially  from  the  connecting-rod  bearings 
just  shown  and  described.  They  may  be  a  little  longer,  but  the  type 
is  the  same.  They  are  pinned  orotherwisefastened  in  the  crankcase  so 
83  not  to  rotate,  while  the  connecting-rod  bearings  are  fastened  in  the 
connecting  rods  so  as  to  rotate  with  them.  A  few  shafts  will  be  met 
which  have  ball  or  roller  bearings,  but  the  great  majority  have  the  split 
bronze-backed,  babbitt-faced  bearing  described  for  connecting  rods. 

Crankshaft  and  Connecting-Rod  Bearing  Shims.  Practically  all 
split  or  two-piece  bearings  for  either  crankshafts  or  connecting  rods 
are  assembled  in  place  with  shims.  These  are  very  thin  flat  pieces 
of  metal  set  between  the  two  halves  of  the  bearing  when  it  is 
assembled  new  to  spread  it  apart.  The  shaft  bearings  are  scraped  to 
an  exact  fit  on  the  pins  with  these  shims  or  expanders  in  place.  Then 
when  wear  occiu?  in  the  bearing,  so  that  its  inside  diameter  is  enlarged, 
the  bolts  may  be  taken  out,  a  shim  or  shims  of  the  required  thickness 
removed,  and  the  bolts  put  back  and  tightened.  This  removal 
reduces  the  diameter  of  the  inside  of  the  bearing.  To  facilitate  this 
action,  the  shims  are  generally  put  in,  in  such  a  way  as  to  allow  taking 
out  a  number  of  thousandths  of  an  inch,  there  being  two  shims  of 
rAr,  two  or  more  of  nftnr,  possibly  one  of  nftnr,  and  a  thicker  one,  or 
more  of  the  very  thin  ones.    These  shims  enable  the  taking-up  of  wear 


76  GASOLINE  AUTOMOBILES 

amounting  to  lo'oo  of  an  inch,  when  one  of  the  thinnest  shims  is 
removed;  tAt  by  removing  one  of  that  thickness;  m'aa  by  removing 
a  TTsW  and  a  tAu;  iTAnF  by  taking  two  2's,  etc. 

Of  course,  a  crankshaft  bearing  or  a  connecting  rod-bearing  will 
not  wear  entirely  round,  but  the  work  of  adjusting  either  bearing  is 
reduced  to  a  minimum  by  the  use  of  shims.  When  the  wear  is  verj" 
bad,  the  bearings  should  be  re-fitted  and  the  shims  left  out. 

An  entirely  new  form  is  the  laminated  shim.  The  total  thickness 
required  b  built  up  of  very  thin  laminations,  either  one  or  two 
thousandths  of  an  inch  thick,  so  that  in  adjusting  a  bearing  as  many 
laminations  are  peeled  off  as  are  necessary  to  take  up  the  wear,  thai 
the  original  shim,  slightly  lessened  in  thickness  is  rephtced. 

In  Fig.  66,  the  end  view  shows  both  connecting-rod  and  crank- 
shaft bearing  shims  in  place,  and  indicates  how  they  perform  their 
function  of  holding  the  halves  of  the  bearing  apart  when  the  bearing 
is  being  fitted. 

Crankshaft  and  Bearing  Troubles,  and  Remedies 

Bearings.  Bearings  of  the  two-piece,  or  split,  type  pve  the. 
auto  repair  man  fully  as  much  trouble  as  anything,  in  fact,  the 
crankshaft  bearings  should  not  be  tackled  until  considerable  repair 
experience  has  been  had.  In  general,  wear  on  the  bearings  is  due 
to  one  of  two  causes:  either  to  a  soft  metal  which  has  caused  vertical 
wear  on  the  inside  or  outside  of  the  lower  half  of  the  bushing,  or  to  a 
vibrating  shaft  which  has  worn  an  oval  hole  somewhere  in  the  length 


GASOLINE  AUTOMOBILES 


vill  not  fit  the  boles  in  the  case;  or 
possibly  the  wear  may  have  com- 
municated   itself  to  the   case,    so 
that  the  hole  there  is  out  of  true. 
If  this  be  slight,  refilling  the  cases 
with  babbitt  metal  or  building-up 
may  be  resorted  to,  but  if  tlie  wear 
is  considerable,  a  new  set  of  bear- 
ings is  the  only  remedy.     In  build- 
ing up  the  bearing,  strips  of  aoft 
metal  are  placed  in  the  worn  spots, 
after  cutting  or  filing  them  to  fit 
as  closely  as  possible,  and  the  bear- 
ing driven  down  upon  them  as  firmly 
as  possible.     In  this  way,  it  is  often 
possible  to  build  up  a  worn  crank- 
case  to  answer  for  many  thousand 
more  miles  running. 

Bearing  Wear.  In  this  connec- 
tion, it  is  important  to  know  how 
and  why  bearings  wear.  Normally, 
between  the  crankshaft  bearing  and 
the  pin,  there  is  a  space  of  perhaps 
.002  inch  divided  into  .001  inch  all 
around,  and  this  space  is  occupied 
by  a  fihn  of  lubricant.  So  long  as 
this  is  the  case,  if  the  metal  remains 
hard  and  does  not  give  under  the 
constant  pounding,  and  the  film  of 
lubricant  stays  unbroken,  it  remains 
a  perfect  hearing.  But  the  film  does 
get  broken  or  reduced,  and  the  softer 
metal  does  give,  so  we  have  a  con- 
dition shown  at  A,  Fig.  69.  Instead 
of  a  cylindrical  pin  centered  in  a 
cytiodrical  hole,  one  or  the  other  is 
worn  oval.  This  is  usually  the 
bearing,  for    the   weight    of    the 


78 


GASOLINE  AUTOMOBILES 


shaft,  coupled  with  the  pressure  on  it,  keeps  it  at  the  bottom  of 
the  hole.  The  tendency,  then,  is  to  increase  this  eccentricity. 
In  this  condition,  the  pin  is  running  against  the  bearing  metal  at 
only  one  very  limited  surface,  so  all  the  pressure  and  all  the  wear  are 
concentrated  there.  If  tlie  bearing  is  hard,  or  if  a  hard  spot  develops, 
the  pin  is  likely  to  wear  flat  on  the  bottom  side,  as  shown  at  B.  When 
the  bearing  is  fitted  to  the  case,  great  care  and  accuracy  are  required, 
I£  care  is  not  taken,  an  incorrect  fitting,  shown  at  C,  results.  Here 
the  shim  does  not  entirely  fill  the  opening  for  it,  and  the  bearing  metal 
rests  on  the  case  at  one  point;  on  the  shim  at  another;  and  does  not 
touch  either  at  a  third.  This  is  remedied  by  scraping  both  bearing 
and  case,  as  shown  at  73,  or  the  shim  alone  as  seen  at  £.  In  the  former 
it  will  be  noted  how  the  full  shim  has  raised  the  bearing  so  that  its 
points  project  into  the  pin, 
where  scraping  will  be  needed. 
In  the  latter  case,  also,  scrap- 
ing the  bottom  of  the  bearing 
will  be  necessarj',  for  using  a 
y  fitted  shim  has  raised  the 


GASOUNE  AUTOMOBILES 


79 


this:  If  the  rod  is  placed  vertical,  it  will  stay  there,  but  if  pulled 
over  past  20  decrees  from  a  vertical,  it  vill  swing  down,  of  itself, 
to  the  bottom  position  and  stop  there 
widiout  continuing  to  swing.  If  it 
will  do  this,  it  is  just  tight  enough .  If 
it  will  not  swing  down  at  all  or  con- 
tinues swinging,  it  is  either  too  tight 
or  too  loose.  To  a  certain  extent, 
crankshaft  bearings  are  delicate,  and 
they  can  be  mined  by  having  the 
big  ends  too  tight. 

Holder  for  Bearing  Caps.  When 
a  number  of  bearing  caps  have  to  be 
scraped,  or  filed  down,  it  is  worth 
while  to  make  a  holder  for  them.  A 
plain  form  is  shown  in  Fig.  70.  This 
consists  of  a  semicircular  piece  of 
metal  which  fits  into  the  hollow  part 
of  the  bearing,  with  each  end  pivoted  pj^  , 
on  two  L-shaped  members.  Themem-  — .>««™m.,u>. 

bers  are  held  tightly  in  the  vise,  and  the  tighter  they  are  gripped  the 
tighter  the  bearing  cap  is  held.    This  jig  holds  the  cap  with  the  desired 


r^ 


8eiiii-8<Hket  Wreneb  lot  Cnuk- 


fit,  73.    8at-Up  tat  Suppoctina  Cnnlnlwfta  O' 

firmness,  yet  it  leaves  the  whole  upper  surface  free  and  clear  so  the 
workman  can  work  at  it  readily  and  do  a  neat  quick  job  of  iiw.%. 


GASOLINE   AUTOMOBILES 


The  same  layout  is  suitable  for  connecting-rod  caps,  except  where  they 
have  an  oil  scoop  or  other  central  projection  which  interferes. 

Another  Handy  Wrench,  The  form  of  the  crankshaft-bearing 
cap  and  also  of  the  connecting-rod  bearing  cap  are  such  that  no  space 
is  wasted.  Very  often  the  nut  is  so  close  to  the  cap  that  it  is  difficult 
to  turn,  unless  the  cap  is  taken  out  of  the  motor  where  the  wrench  can 
be  applied  at  right  angles.     The  use  of  the  socket  form  of  wTench, 


GASOLINE  AUTOMOBILES 


81 


the  form  made  of  tubing,  and  has  part  of  one  side  of  the  socket  cut 
away.  Tbb  makes  its  quick  application  to  the  nuts  easy,  although 
it  also  limits  the  amount  of  turn  possible.  Generally  the  case  nuts 
are  different  in  size  from  the  connecting-rod  nuts;  so  it  is  advisable  to 
make  the  wrench  double  ended  with  a  size  at  one  end  for  the  rods, 
and  one  at  the  other  end  for  the  case. 

Holding  the  Crankshaft.  When  the  shaft  has  been  removed  from 
the  engine,  and  work  is  to  be  done  upon  it,  it  is  an  awkward  thing  to 
handle.  It  is  just  delicate  enough  so  that  it  cannot  be  handled  care- 
lessly, yet  its  size  and  weight  make  it  difficult  to  move  around. 
Hius,  in  lapping  the  shaft  pins,  in  fitting  connecting-rod  bearings,  or 
doing  other  work  upon  it,  a  sup- 
pMt  which  is  »mple,  easily  moved 
utiond,  yet  adequate,  is  needed. 
Ordinarily  a  shaft  is  clamped  in  a 
viae,  but  this  is  not  always  satis- 
fiwtory  when  working  on  an  end 
bearing.  The  method  shown  in 
fig.  72  has  many  advantages. 
llus  consists  of  a  special  bench 
fixture  and  a  notched  board.  The 
latter  should  be  at  least  1-inch 
stodc,  that  is,  it  should  be  J-inch 
when  dressed  on  both  sides.  The 
forma:  is  simply  a  metal  angle  with 
a  series  of  radial  slots  to  take  the 
fiywheel  bolts,  with  a  central  hole 
for  the  shaft  to  rest  in.  The  metal  above  the  hole  is  well  cut 
away  to  facilitate  putting  the  shaft  in  and  taking  it  out. 

HandUif  Shaft  in  Machines.  When  the  crankshaft  is  to  be 
machined,  no  matter  what  the  form  of  lathe,  grinder,  or  other  machine, 
the  fart  that  the  pins  are  eccentric  necessitates  a  special  dog  or  jig 
for  holding  it.  If  an  ordinary  flange  is  bolted  on  the  end,  the  main 
pins  can  be  turned,  smoothed  down,  or  ground,  but  the  crankpins 
cannot.  What  these  latter  need  is  a  form  of  flange  or  plate  with  two 
exact  centers  on  either  side  of  the  central  one  at  distances  exactly 
equal  to  the  CTank  throw.  One  is  shown  in  Fig.  73,  which  is  attached 
to  a  four-cylinder  shaft  all  ready  for  the  machine.    Above  w\^  \i« 


S2 


GASOLINE  AUTOMOBILES 


seen  another  shaft  witliout  machining  flanges.  The  bolts  which 
attach  the  flanges  to  the  shaft  can  be  seen  beyond  the  right-hand 
flange  and  at  the  far  end.  The  rack  in  the  background,  on  which 
these  shafts  are  placed,  is  of  interest  also,  forming,  as  it  does,  a  simple 
and  efficient  means  of  holding  the  shafts,  jet  it  is  convertible  for 
holding  other  parts  or  units.  It  is  simply  a  stout  form  of  horse. 
rather  high,  and  with  three  legs  instead  of  the  usual  two.  The  braces 
are  all  put  on  the  inside  to  leave  the  surface  clear,  while  the  support- 
ing pins  differ  only  in  length.     In  this  case  they  have  been   made 


GASOLINE  AUTOMOBltES 


ig  Fiiture  ol  Sinjple  Cowtni 


Adjustable  Crankshaft  Flanges.  In  the  small  shop  the  general 
run  of  work  varies  30  much  that  the  principal  difficulty  lies  in  having 
flanges,  dogs,  or  fixtures  for  handling  the  variety  of  crankshafts  that 
come  in.  Diameters  vary  30  much  that  a  wide  range  of  central  holes 
is  needed,  because  throws 
are  all  different.  This 
gives  a  different  center 
to  center  distance;  then, 
too,  there  are  still  one- 
and  two-throw,  and 
other  old  forms  of  shafts 
in  use,    which  come  in 

occasionally  for  repairs.  For  these  reasons,  it  is  not  wise  for  the  small 
shop  to  go  too  far  into  special  crankshaft  fixtures;  it  should  stick  to 
simple  dogs,  with  adjustable  center  distances,  like  the  three  shown  in 
Fig.  75.  While  the  shaft  indicated  is  a  single-cylinder  form,  dogs  of  this 
tj-pe  can  be  used  on  other  forms.  This  constitutes  their  biggest  advan- 
tage.  The  variation  in  the  three  is  self-explanatory  to  any  machinist. 

Crankshaft  Lapping.  The  pins  of  a  crankshaft  need  lapping 
the  same  as  other  pins  where  a  grinding  machine  is  not  available. 
There  are  two  ways  of  doing  this:  by  hand,  which  is  slower  but  more 
simple  so  far  as  apparatus  is  concerned;  and  by  machine,  which 
requires  special  fittings  for  this  purpose.  In  the  sketch,  Fig.  76,  a 
form  of  hand  tapper  is  shown.  This  consists  of  a  pair  of  hinged 
members,  with  a  central 
hole  lai^  enough  to 
take  various  sizes  of 
bushings,  such  as  would 
be  required  on  different 
shafts.  A  long  handle 
is  provided ;  also  a  bolt 
to  hold  the  two  halves 
together  when  the  bush- 
ing has  been  inserted. 
The  babbitt  bushing  must  be  split  and  have  end  flanges  to  hpid 
the  halves  In  place  sideways.  The  handle  gives  leverage  for  work- 
ing the  tool,  which  is  made  effective  by  the  application  of  fine  emery 
and  oil  on  the  pins  to  be  lapped.    In  the  same  way,  the  pins  are  pol- 


Flg.  77.     Lathe  S«t-Up 


r  Lapping  Crankshaft  Piu 


84  GASOLINE  AUTOMOBILES 

ished  by  means  of  a  pair  of  long  wooden  clamps,  shown  below,  and 
made  in  somewhat  the  same  way.  There  is  a  hinge  at  the  back;  and 
the  abrasive  used  is  fine  emery  cloth,  which  is  flooded  with  oil. 

The  throws  on  the  crankshaft  can  be  lapped  in  the  lathe  by 

putting  it  between  centers  for  tlie  main  bearings  and  by  us'iiig  a 
special  flange  for  the  other  pins.  A  method  which  can  be  used  is 
shown  in  Fig.  77.  This  consists  of  a  special  fixture,  made  from  a 
large  casting  with  a  base  to  fasten  to  the  face  plate;  a  long  extension 
arm,  having  a  split  end  for  attaching  and  detaching,  to  encircle  the 
throw  to  be  lapped.  When  this  is  used,  the  shaft  is  supported  in 
V-blocks,  somewhat  flexibly  it  is  true,  but  sufficiently. 

Welding  Shafts  and  Cases.  The  welding  of  broken  crankshafts 
and  crankcascs,  such  as  central  breaks,  breaks  around  the  cylinder 
supporting  surface,  bearing  supports,  and  supporting  arms  will  be 
found  fully  discussed  under  the  subject  of  welding,  with  full  direc- 
tions as  to  the  preparation  of  the  work,  the  materials,  and  other  details. 

CRANKCASES 
Function  of  Crankcase.     The  lower  part  of  the  motor  car,  truck, 
or  tractor  engine  is  generally  enclosed  for  the  purpose  of  assisting  the 


GASOLINE  AUTOMOBILES  85 

A  section  through  a  modern  crankcsse  is  shown  in  Fig.  78,  whidi 
illustrates  a  twelve-cylinder  motor.  Note  the  inclined  upper  sur- 
faces of  the  upper  half  to  which  the  cylinders  are  bolted  and  the 
stiffening  rib  at  the  center  line  where  the  two  halves  meet.  Note 
also  how  the  lower  half  is  simply  an  enclosure,  carrying  only  the  oil 
strainer  (shown)  and  the  oil  pump  (not  shown).  It  has  cooling  fins  cast 
on  its  lower  surface  to  keep  the  temperature  of  the  oil  down.  The 
shelf,  which  is  cast  on  the  upper  half  to  close  the  space  between  the 


Fis.  78.    Section  tliroush  Cnnkcan  ol  Box  Type  fm  Twelve-Cylinder 
V-Type  Pw:kud  Motor 

sides  of  the  crankcase  and  the  chassis  frame,  serves  the  double  purpose 
of  a  protecting  pan  to  keep  out  road  dirt  and  water  and  of  a  supporting 
shelf  for  accessories.    Fig.  79  shows  the  same  engine  from  the  front. 

Crankcases  are  made  mostly  in  two  forms:  the  box  type,  which 
has  more  or  less  straight  sides,  with  a  fiat  top  and  bottom;  and  the 
barrel  type,  wMch  is  round  or  a  modified  round  with  a  fiat  bottom  and 
top.  The  one  shown  is  of  the  box  type;  the  barrel  type  is  generally 
not  split  along  the  center  line,  but  it  has  removable  end  plates  which 
allow  the  insertion  of  the  crankshaft  and  a  very  simple  bottom  plate 
which  carries  the  oil  supply.  The  one-piece  type  b  supposed  to  give 
greater  rigidity,  but  thb  is  at  the  expense  of  accessibility. 

Modem  Tendencies  in  Design.  There  are  two  modem  ten- 
dencies shaping  toward  a  modification  of,  or  the  entire  elimination  (A, 


86  GASOLINE  AUTOMOBILES 

the  lower  lialf  of  the  crankcase  as  it  is  now  known.  One  is  the  mini- 
mizing of  its  functions,  so  it  can  be  made  of  pressed  steel,  when  it 
becomes  a  cover  onl\-,  and  the  oihng  system  is  made  such  that  the 
supply  is  carrieii  elsewhere.  The  other  is  the  casting  of  parts  of 
the  crankcase  inteftrally  with  the  cylinders.  This  has  been  done 
3uccessfull\-  witli  the  Marmon.  the  Ford,  and  with  others,  in  which  the 
cylinder  block  and  the  upper  half  of  the  crankcase  are  cast  as  one.     If 


GASOLINE  AUTOMOBILES  87 

crankcase,  it  is  an  all  day's  job  to  take  out  a  piston  and  replace  it. 
When  the  cylinders  are  separate,  cast  in  pairs,  or  bolted  on,  a  piston 
can  be  taken  out  and  replaced  in  a  couple  of  hours. 

Crankcase  Materials.  It  is  important  that  the  repair  man 
should  know  the  materials  of  which  both  upper  and  lower  halves  of 
the  crankcase  and  the  gear  cover  are  composed,  for  these  may  need 
repairing.  In  general,  crankcases  are  of  aluminum  alloy,  the  exact 
composition  varying.  When  this  is  the  material,  the  gear  cover  is 
of  aluminum  alloy  also.  A  few  crankcases  are  made  of  cast  iron,  on 
very  low  priced  cars.  Others  have  the  pressed-steel  oil  pan,  pre- 
viously mentioned.  A  few  high-grade  cars  have  bronze  crankcases; 
these  are  either  government  bronze  or  vanadium  bronze. 

Crankcase  Arms  and  Engine  Supports.  The  engine  is  generally 
supported  by  crankcase  arms  extended  from  the  sides  or  ends  of  the 
upper  half  of  the  crankcase  and  cast  integrally.  However,  this  is  not 
always  the  case.  In  many  unit  power  plants,  the  rear  pair  of  sup- 
porting arms  may  be  fixed  to  the  fl^-wheel  housing  or  to  the  transmis- 
sion case.  Moreover,  separate  supporting  members  bolted  or  hinged 
in  place  may  be  used.  These  are  heavy  steel  forgings,  stout  bronze 
castings,  or  heavy  gage  steel  tubing.  This  may  be  done  to  allow 
the  engine  freedom  of  slight  rotation  and  relieve  it  of  twisting  due  to 
road  inequalities;  it  may  be  done  because  of  lack  of  confidence  in  the 
strength  of  the  crankcase  material  as  an- engine  support;  it  may  be 
done  to  facilitate  foundry  work  on  the  crankcase,  and  thus  reduce  its 
cost;  or  for  other  reasons.  In  taking  out  an  engine,  the  repair  man 
should  find  out  about  this,  as  it  may  simplify  or  complicate  the  removal. 

Qear  Cases,  or  Gear  Covers.  At  the  front  end  of  the  great 
majority  of  engines,  the  gears  which  determine  the  working  of  the 
engine  and  its  accessories  are  placed.  These  may  include  the  crank- 
shaft driving  gear  and  any  or  all  of  the  following  driven  gears :  camshaft 
gear,  magneto  gear,  water-pump  gear,  lighting-generator  gear,  oil- 
pump  gear,  and  sometimes  fan  gear  and  air-pump  gear.  These  may 
be  driven  directly  by  gear  contact  or  by  means  of  silent  chains.  In 
either  case  the  gears  are  enclosed  by  a  case  or  cover,  variously  called 
the  gear  case,  gear  cover,  or  cam-gear  cover.  This  housing  is  generally 
of  as  simple  a  shape  as  possible,  and  is  bolted  in  place  with  as  few 
bolts  as  possible  in  the  lower  half  of  the  crankcase,  so  as  to  facilitate 
its  removal  for  crankshaft  or  other  bearing  inspection  or  for  repair. 


88  GASOLINE  AUTOMOBILES 

Other  details  of  the  crankcase  parts,  not  previously  discussed, 
will  be  taken  up  under  the  groups  in  which  they  belong;  for  instance, 
camshafts  and  cams  with  valves  and  valve  parts;  lubricating  parts, 
drilling  in  crankshafts  for  lubricating  purposes,  oil  passages  in  the 
crankcase,  etc.,  under  lubrication;  and  others  under  their  respective 
groups. 

Crankcase  Troubles  and  Remediet 

General  Nature  of  Troubles.  The  most  general  crankcase 
trouble,  aside  from  bearing  trouble,  is  breakage.  The  usual  bearing 
troubles  previously  outlined  occur  as  well  with  main  crankcase 
bearings.  These  require  similar  attention,  and  in  their  handling 
much  special  apparatus,  such  as  stands,  jigs,  fixtures,  and  tools,  can 
be  developed  by  the  ingenious  repair  man.  Worn  main  bearings 
cause  a  knock.  If  this  comes  from  any  one  bearing,  it  can  usually 
be  traced  quickly.  The  use  of  the  stethoscope  is  recommended  tot 
any  crankcase  or  gear-cover  noises  or  troubles.  A  squeak  from  any 
part  of  the  crankcase  usually  means  a  lack  of  oil  or  the  rubbing  ,of 
parts  which  should  not  rub. 

Mending  Breaks.  If  the  case  is  of  aluminum,  it  should  be 
watched  carefully  for  breaks  or  cracks.  If  a  crack  develops,  it  should 
be  drilled,  plugged,  and  welded,  as  cyhnder  water  jackets.    This  iriU 


GASOLINE  AirrOMOBILES  89 

to  vash  wdl  enough  and  long  enough  to  Trmove  all  the  acid. 
Moreovef,  it  should  be  kept  from  clothes  or  from  any  nood  parts,  as 
it  is  strong  enough  to  attack  fabrics  end  wood. 

The  aluminum  oil  pan  should  be  cleaned  out  at  least  once  A 
season,  for  the  strainer  will  separate  a  lot  of  dirt  and  dust,  as  well  as 
otiier  foreign  matter,  from  the  oil  in  the  course  of  8  or  9  months. 
This  will  be  found  in  the  bottom  of  the  oil  pump  or  beneath  the  oil 
proper,  as  a  kind  of  slush  or  sludge.  Sometimes  it  is  thick  enough 
to  need  stTaping,  particularly  in  sandy  country  where  the  car  gets 
little  or  no  care.  Generally,  a  kerosene  bath  will  dean  it  out.  This 
is  followed  by  a  "onceK>ver"  with  gasoline  to  clean  off  the  kerosene 


and  the  last  of  the  dirt.  If  any  gasoline  remains,  it  will  evaporate 
and  leave  a  crankcase  which '  actually  is  clean.  The  porosity  of 
aluminum  emphames  this  need  for  a  thorough  cleaning,  which  is  not 
needed  so  badly  with  pressed-steel  oil  pans. 

Machining  Crankcases.  Generally  speaking,  the  repair  man 
will  not  be  called  upon  to  do  any  machining  on  crankcases,  beyond 
something  like  chipping  or  filing,  or  in  the  case  of  a  break,  patching 
or  welding.  But  in  case  such  a  job  should  come  along,  it  is  important 
to  know  how  to  handle  it,  for  there  is  no  more  important  crankcase 
job  than  the  machining  of  the  main  bearings.  The  necessity  here 
is  to  keep  them  in  perfect  alignment,  and  this  necessitates  machin- 


90  GASOLINE  AUTOMOBILES 

ing  all  of  them  at  once  with  a  long  boring  bar,  as  shown  in  Fig.  80. 
The  method  of  support  upon  the  flat  upper,  or  cylinder,  face  will  be 
noted,  also  the  holding  down  blocks  bolted  to  the  table  of  the  machine, 
after  being  bolted  to  the  cylinder  studs.  The  provision  for  lubricant 
on  each  one  of  the  boring  cutters  will  be  seen  in  the  small  copper  pipes 
above  and  at  the  back.  As  the  average  shop  does  not  have  a  boring 
tool  of  this  kind,  this  work  will  have  to  be  approximated.  It  could  be 
done  by  hand,  using  the  now  well-known  Martell  aligning  reamer, 
to  ream  the  hearings  out  and  put  in  new  and  larger  bushings.  This 
also  has  a  series  of  cutters,  much  like  the  boring  bar  shown,  and  is 
actuated  by  hand.  So  the  principal  requisite  would  be  a  large  flat 
surface  on  which  to  work.  Possibly  .this  will  be  found  at  the  drill- 
press  platen,  the  planer  table,  or  the  working  table  of  whatever  large 
machine  tool  the  shop  possesses.  In  this  job,  the  workmen  should 
remember  that  unless  the  case  is  held  firmly  throughout,  it  is  likely 
to  give  or  spring,  and  this  will  spoil  the  whole  job,  no  matter  "how  good 
it  may  be  otherwise. 

In  all  orankcase  repairs,  the  repair  man  should  remember  that 
the  case  is  really  the  foundation  of  the  engine,  and  if  it  is  not  firm 
of  itself  and  firmly  supported,  the  action  of  the  engine  cannot  be 
positive  nor  continuous.     Consequently  the  case  should  be  handled 


GASOLINE  AUTOMOBILES  91 

SUMMARY  OF  GENERAL  AUTOMOBILE  INSTRUCTIONS 

Q.  Into  how  many  main  groups  can  the  mechanical  parts  of  tlie 
car  DC  ciivKieGr 

A.  Practically  all  motor  cars  can  be  di\nded  into  six  general 
poups  as  follows:  (1)  engine,  or  power-producing,  group;  (2)  clutch, 
or  engine  connecting  and  disconnecting,  group;  (3)  transmission,  or 
qpeed-var>dng,  group;  (4)  final-drive  group  including  rear  wheels; 
(5)  steering  group  for  controlling  the  direction  of  the  car  and  including 
front  wheels  and  axle;  (6)  frame  upon  which  all  otiier  groups  except 
vheels  are  hung.  The  body  makes  a  seventh  group,  but  strictly 
speaking  it  is  not  mechanical. 

Q.     How    many    sub-groups    are    there   pertaining    to    the 


A.  According  to  their  functions,  the  parts  and  accessories  of 
the  engine  may  be  subdivided  into  10  groups:  (1)  cylinders,  pistons, 
connecting  rods,  crankshaft,  and  other  basic  parts;  (2)  carburetion 
sub-group  through  which  the  mixture  is  supplied  which  enables  the 
engine  to  run;  (3)  valve  group  through  which  the  mixture  is  allowed 
to  enter  and  leave  the  cylinders  at  the  correct  time;  (4)  exhausting 
system  through  which  the  burned  gases  are  led  away  from  the  motor; 
(5)  ignition  system  by  means  of  which  the  mLxture  in  the  cylinders  is 
ignited  at  the  proper  time;  (6)  cooling  system  by  means  of  which  the 
tem[>erature  of  the  motor  is  kept  down  to  a  point  at  which  it  can 
operate  safely  and  continuously;  (7)  lubrication  sub-group  by  means 
of  which  the  rotating,  or  rubbing,  parts  are  kept  lubricated  so  as  to 
run  without  friction  or  heat;  (8)  starting  sub-group  by  means  of  which 
the  motor  is  started;  (9)  hghting  sub-group  through  which  the  car  is 
lighted,  not  strictly  an  engine  part  but  closely  allied  with  starting 
and  ignition,  and  because  of  its  drive  from  the  engine  and  general 
location  of  its  parts  on  it,  it  is  classed  as  an  engine  sub-group;  (10) 
fl^'wheel  sub-group.  The  last  is  really  a  single  unit  but  its  size, 
weight,  shape,  location,  attachment,  and  other  points  are  becoming 
so  important  as  to  warrant  separate  consideration. 

Q.    Why  is  it  necessary  to  conskler  each  of  these  separately? 

A.  Because  their. functions  all  diflFer.  The  very  things  which 
make  each  grou^  best  fitted  to  its  work  make  it  more  widely  different 
from  each  of  the  others.  Some  groups  are  so  very  different  as  to 
warrant  separate  consideration,  almost  as  extended  as  the  balance  of 


92  GASOLINE  AUTOMOBILES 

the  motor  group,  as,  for  instance,  ignition,  starting,  and  lighting, 
which  naturally  group  together. 

Q.    What  are  the  most  popular  cylinder  forms? 

A.  Automobile  engine  cylinders  are  mainly  of  the  following 
forms:  (1)  cast  in  pairs;  (2)  cast  in  block;  (3)  cast  in  threes,  in  the  case 
of  six-cylinder  motors.     The  last  is  really  a  modification  of  the  first. 

Q.    What  are  the  advantages  of  each  of  these? 

A.  The  cast-in-pairs  form  can  be  removed  by  one  man  and 
replaced  by  two,  if  it  is  broken,  cracked,  or  damaged;  replacement 
is  less  expensive;  the  casting  is  less  complicated,  consequently  there  is 
less  waste  in  the  foundry;  they  are  easier  to  machine,  store,  ship, 
handle;  they  also  have  other  advantages.  All  these  apply  to  the 
cast-in-threes  modification.  The  cast-in-block  form  makes  a  more 
simple  looking  engine,  a  shorter  and  more  compact  one,  and  renders 
alignment  and  spacing  more  accurate  and  permanent.  Furthermore, 
all  water,  inlet,  exhaust,  and  other  connections  may  be  cast  integral, 
which  is  not  |H)ssible  with  the  cast-in-pairs  or  cast-in-threes  forms. 
Similarly,  the  crankcase  may  be  cast  integral  if  desired. 

Q.    Mow  is  the  weight  of  reciprocating  parts  lessened? 

A.  In  the  case  of  pistons,  this  may  be  done  in  one  of  three  ways: 
0)  till.-  form,  shape,  size,  ami  m:itcrial  nmy  remain  uiicluitipcil,  whili 


GASOLINE  AUTOMOBILES  93 

Q.  Is  there  a  noticeable  tendency  toward  simplicity  in  connect- 
ing-rod constructions? 

A.  Yes,  the  same  as  in  pistons  and  rings,  toward  simplification 
and  lightening  of  the  weight,  with  the  removal  of  all  superfluous 
pwtrts.  Two  bolts  are  becoming  the  standard  for  the  big  end.  The 
H-section  machined  all  over  is  almost  universal,  smaller  sections  being 
used  than  formerly.  Pressed-in  wrist-pin  bearings  of  comparatively 
thin  walls  are  being  used  and  a  better  class  of  material  generally, 
which  allows  lighter  weight  and  smaller  sizes  for  equal  or  greater 
strength.  Lubrication  scoops  are  being  machined-in  in  the  forms  of 
holds,  and  a  simple  projecting  lip  instead  of  former  brass  tubes, 
which  were  added. 

Q.  What  is  the  accepted  type  of  connecting-rod  big-end 
bearing? 

A.  The  split,  or  two-piece,  form  with  a  shell  or  backing  of 
bronze  and  a  facing,  or  wearing  surface,  of  babbitt  with  oil  holes 
drilled  through  and  the  interior  surfaces  oil-grooved  to  and  from  these 
to  distribute  the  oil  evenly. 

Q.    Why  is  this  the  accepted  form? 

A.  The  bronze  backing  or  shell  gives  the  desired  stiffness  and 
permanence,  also  machines  well  and  resists  overheating  well.  The 
babbitt  facing,  when  worn,  is  easily  replaced  by  any  repair  man,  and 
it  will  melt  out  in  case  of  lubrication  neglect  so  little  harm  is  done, 
yet  when  well-fitted  it  gives  a  fine  bearing  surface.  The  system  of 
drilling  and  grooving  supplies  a  film  of  oil  at  all  times.  These 
materials  and  this  arrangement  supply  an  almost  ideal  combination 
when  well-made  and  fitted,  hence  their  wide  acceptance. 

Q.    What  difference  is  noted  in  V-type  engine  bearings? 

A.  When  the  two  rods  of  a  V-type  engine  act  upon  a  single 
pin,  the  arrangement  of  the  bearings  must  be  such  that  one  must  be 
notched  out,  or  divided,  to  make  room  for  the  second,  or  else  the 
exterior  of  the  first  must  be  formed  as  a  bearing  surface  for  the  second. 
In  the  former  case,  the  one  bearing  is  practically  in  four  parts;  in  the 
latter,  the  exterior  of  the  inner  bearing  becomes  as  important  as  its 
interior  surface,  since  it  acts  as  the  bearing  pin  for  the  outer  rod. 

Q.    Name  two  general  forms  of  crankshaft  today. 

A.  The  single-plane  type  and  the  multi-plane  type.  In  the 
former,  as  used  on  four-  and  eight-cylinder  engines,  all  pins,  bearings^ 


U  GASOLINE  AUTOMOBILES 

and  webs  are  in  one  plane.  In  the  latter,  as  used  on  six-  and  twelve- 
jylimler  engines,  the  pins  are  in  three  planes  set  at  an  angle  of  120 
degreew  with  each  other. 

Q.  How  many  different  forms  of  four-cylinder  shafts  are 
there? 

A.  There  are  but  three  radically  different  forms  of  four- 
cylinder  crankshafts,  depending  upon  the  bearings.  These  are: 
(1)  The  shaft  in  which  there  is  a  bearing  on  each  side  of  each  appli- 
cation of  power,  or  five  bearings  m  all;  (2)  the  form  in  which  there  is  a 
bearing  at  each  end  and  one  in  the  middle,  or  three  bearings  in  all; 
(3)  the  form  in  which  there  are  no  center  bearings,  but  only  the 
two  end  bearings.  The  first  is  used  on  the  highest-priced  four- 
cylinder  cars,  becau.se  it  is  expensive  of  itself  and  has  a  similar 
influence  on  other  parts,  notably  bearings,  crankcase,  etc.  The 
second  is  in  wide  use;  being  the  most  popular  form.  The  last 
is  used  only  when  extreme  compactness  is  desired.  There  is  an 
odd  form  of  shaft  in  which  four  bearings  are  used,  but  only  one 
maker  ever  used  it. 

Q.  What  is  the  difference  in  the  average  of  six-cylinder  crank- 
shafts? 


GASOLINE  AUTOMOBILES  95 

The  general  type  is  the  same,  also  the  number  of  bearings.  This 
applies  to  fom^,  sixes,  eights,  twelves,  or  to  any  form. 

Q.    What  are  shims,  and  for  what  are  they  used? 

A.  Shims  are  very  thin  pieces  of  metal  placed  between  the 
two  halves  of  bearing  caps  for  the  purpose  of  giving  a  quick,  simple, 
easy  adjustment  when  the  bearing  wears.  In  theory,  this  works  as 
follows:  When  a  bearing  has  worn  down  i(fto'  inch,  the  cap  is  un- 
screwed and  removed,  and  shims  of  a  thickness  of  ttAht  inch  are  taken 
out  on  each  side.  Then  the  cap  is  replaced  and  tightened,  and  the 
bearing  is  as  good  as  new*.  In  actual  practice,  the  removal  of  the 
shims  creates  a  shape  of  bearing  which  is  not  an  exact  circle,  so  that 
some  slight  scraping  with  very  little  wear,  is  necessary,  as  illustrated 
above,  and  a  great  deal  of  rescraping  and  refitting  (in  addition  to 
shim  removal)  with  greater  wear. 

Q.    For  what  is  a  crankcase  used? 

A.  The  crankcase  is  used  to  support  the  cylinders  and  the 
crankshaft;  to  act  as  a  housing  to  keep  out  dust  and  dirt  and  as  a 
retainer  and  reservoir  to  hold  the  oil  in. 

Q.    What  is  its  general  shape? 

A.  Generally,  crankcases  are  either  of  the  box  shape  or  of 
the  round,  or  barrel,  type.  The  first  named  is  generally  split 
horizontally  along  the  crankshaft  center  line;  has  a  flat  top  and  bot- 
tom, with  vertical  sides;  has  the  bearings  supported  in  the  top  half 
only,  the  bottom  acting  simply  as  an  oil  pan.  The  second  form  is 
generally  in  one  piece  with  removable  ends  in  which  two  of  the  shaft 
bearings  are  located;  has  a  rounded  bottom  in  which  the  oil  is  held; 
has  a  flat  top  but  rounded  sides. 

Q.    Of  what  material  is  the  crankcase  constructed  generally? 

A.  Aluminum  and  aluminum  alloys  are  most  widely  used, 
although  there  are  a  number  of  motors  with  cast  iron,  some  with  a 
cast-iron  upper  half  and  a  pressed-steel  or  aluminum  lower  half,  and  a 
few  of  bronze.  The  latter  is  expensive  and  is  losing  ground.  Pressed 
steel  is  suitable  only  for  quantity  production,  while  cast  iron  is  losing 
ground  except  in  those  up-to-date  designs  in  which  the  upper  half 
of  the  case  is  combined  with  the  cylinder  block. 

Q.    How  are  crankcases  supported  on  the  frames? 

A.  The  most  general  method  on  pleasure  cars  is  the  casting 
of  arms,  generally  four,  integral  with  the  crankcase,  these  extending 


96  GASOLINE  AUTOMOBILES 

out  to  and  resting  upon  the  frame,  to  and  through  which  they  are 
fastened.  Generally,  too,  a  thin  web  is  cast  between  the  front  and 
the  rear  arm  on  each  side,  extending  out  horizontally  from  the  sides 
of  the  case  to  the  frame.  This  serves  the  double  purpose  of  replacing 
the  underpan  and  of  acting  as  a  stiffener  for  both  arms  and  case. 
On  a  few  cars  and  on  quite  a  few  trucks,  a  pivoted  cross-arm 
is  used  at  the  front  and  a  bolt  cross-arm  at  the  rear  (or  rice 
Tema),  the.se  being  forged  members.  In  this  way  a  three-point 
support  is  obtained,  which  yields  as  the  frame  is  twisted  or  raised 
unequally. 

Q.     What  is  the  gear  cover  and  what  are  its  functions? 

A.  It  is  the  rernovjible  cover  at  the  front  end  of  the  engine, 
which  covers  and  protects  the  camshaft  and  other  gears  or  silent- 
chain  drives.  In  addition  to  keeping  out  dust  and  dirt  from  these, 
it  minimi7.e3  the  unavoidable  noises  which  they  make  and  retains 
the  lubricant.  It  h  generally  a  Hght  aluminum  shell  held  on  by  a 
dozen  or  less  bohs. 

Q.  What  is  the  general  method  of  lifting  an  engine  out  of  the 
frame? 

A.     By  a  rupr  or  a  chain  sling,  hoistcil  from  above  by  a  chain 


GASOUNB  AUTOMOBILES  97 

locatioQ  in  the  cylinder,  and,  in  part,  upon  the  facilities  whidk  the 
shop  possesses.    The  best  method  varies  with  almost  every  case. 

Q.    What  is  the  most  rapid  method? 

A.  Probably  burning  out  with  oxygen  is  the  quickest  method, 
when  the  shop  possesses  an  oxygen-burning  outfit.  The  spark 
plugs  are  removed  and  their  holes  plugged,  one  or  more  valve  caps 
are  removed  to  allow  working,  the  gas  is  turned  on  and  lighted,  when 
the  workman  can  do  a  cylinder  thoroughly  in  three  or  four  minutes. 
This  means  that  the  entire  process  of  doing  an  engine  will  not  take 
over  twenty-five  to  thirty  minutes.  Any  other  process  will  take  twice 
as  long  as  this. 


i^^m^^^^^^^H 

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^ 

^^^^^57 

_E^ 

3Bf 

GASOLINE  AUTOMOBILES 


PART  II 


ENQINE-QROUP  ELEMENTS— (continued) 

CARBURETORS  AND  CARBURETION 

Function  of  the  Carburetor*  As  has  been  pointed  out  in  the 
general  outline  of  the  motor  car,  the  first  and  most  important  thing 
in  the  engine  cycle  is  to  get  the  fuel  into  the  cylinders.  This  is  done 
through  the  medium  of  the  carburetion  system,  the  principal  unit 
in  which  is  the  carburetor.  The  function  of  this  is  to  convert  a 
liquid  (gasoline)  into  gas  (gasoline  vapor)  measure  this,  and  add 
to  it  the  right  quantity  of  air  to  give  proper  and  complete  combustion. 
If  this  be  not  done,  ix)wer  is  lost,  either  through  the  use  of  too  much 
or  too  little  air.  In  the  latter  case,  not  all  the  fuel  is  vaporized,  hence 
some  of  it  is  wasted. 

This  sounds  like  a  simple  proposition,  yet  its  very  simplicity  has 
been  the  undoing  of  many  automobile  experts.  The  vaporizer 
becomes  more  and  more  complex  each  year,  constant  additions  and 
changes  are  being  made  in  the  other  parts  of  the  system,  and  in  other 
ways  the  carburetion  system  shows  a  constant  change.  Despite  all 
this,  few  fundamental  laws  have  been  found  to  be  in  error,  and  few 
new  ones  have  been  discovered  or  developed. ' 

Effect  of  Heavier  Fuels.  For  some  years  past  there  has  been 
under  way  a  subtle  change  in  the  character  of  the  fuel — the  gasoline 
used  for  the  propulsion  of  automobiles.  The  small  production  and 
the  increasing  demand  have  combined  to  render  almost  unpurchas- 
able,  except  at  high  prices  and  then  from  large  dealers,  the  lighter 
and  more  volatile  gasolines  of  some  years  ago.  In  the  place  of  them 
there  have  been  quietly  introduced  much  heavier  petroleum  dis- 
tillates, which  evaporate  less  readily — though  they  are  actually  of 
higher  value  in  terms  of  power  units.  This  condition  has  compelled 
several  changes  in  the  carburetor  problem. 

In  addition  to  the  foregoing,  in  some  parts  of  the  world  there 
have  been  serious  efforts  made  to  utilize  in  automobile  moloi^ 


100  GASOLINE  AUTOMOBILES 

alcohol  and  benzene  (not  henzjne),  whicti,  with  proper  provision  for 
their  carburetion,  {-onstitute  excellent  fuels. 

The  most  important  of  the  changes  dictated  by  this  development 
in  the  fuel  situation  is  the  now  general  practice  of  heating  the  float 
chambers  of  carburetors,  either  hy  water  from  the  circulating  system 
or  by  exhaust  gases.  An  alternative  scheme  is  that  of  drawing  of  the 
air  for  the  carburetor  from  a  point  adjacent  to  the  exhaust  piping,  ao 
that  this  air  is  sufficiently  warmed  to  readily  take  up  the  gasoline 
necessary  to  constitute  a  proper  explosi\'e  mixture. 

Jacketed  Manifolds.  A  subsequent  and  verj'  successful  method  of 
handling  the  heavier  fuels  is  that  of  jacketing  the  upper  portion  of  the 
inlet  manifold,  and  the  circulating  of  the  hot  water  in  the  cylinder- 
cooling  system  through  this.  By  having  this  jacket  close  to  the  point 
where  the  gaseous  mixture  enters  the  cylinder,  any  remaining  particles 
of  liquid  fuel  are  vaporized  before  entering  the  cylinders.  In  a  few 
instances,  the  same  effect  is  obtained  bj-  incorporating  the  carburetor 
in  the  cylinder  water-jacket  casting.  In  still  others,  where  the  car- 
buretor is  placed  on  one  side  and  the  inlet  valves  on  the  other,  there  is 
a  cored  inlet  passage  through  the  cylinder  block  between  the  cylinders 
which  heats  the  mixture,  with  the  same  result  as  stated  above. 


GASOLINE  AUTOMOBILES  101 

More  Valvet  w.  Forced  Induction.  The  present-day  tendeDcy 
toward  the  use  of  many  valves,  four  per  eylinder,  seems  to  indicate 
a  nece^ty  for  getting  more  gas  into  the  cylinders  in  order  to  get 
more  power  and  speed  from  the  same  size  of  motor.  Thb  would 
seem  to  lead  back  to  the  subject,  agitated  a  few  years  ago  and  dropped 
for  lack  of  interest,  of  the  need  for  forced  induction.  This  will 
introduce  a  greater  quantity  of  gas  into  the  cylinders  without  resort- 
ing to  the  complications  and  trouble-breeding  possibilities  of  four 
valves  per  cj-linder.  It  differs  widelj-  from  fuel  injection,  consisting 
in  its  simplest  form  of  a  special  form  of  fan  or  blower  to  drive  the 
vaporized  fuel  into  the  cylinders. 

Classification  of  Carburetors.  Carburetors,  as  a  whole,  may  be 
divided  into  three  classes:  the  surface  form,  in  which  the  air 
passing  over  the  surface  of  the  fuel  picks  up  some  of  it,  mixes  with  it, 
and  produces  an  explosive  vapor;  the  ebullition,  or  filtering,  tj'pe,  in 
which  air  is  forced  through  a  body  of  fuel  from  below,  absorbing 
small  particles  so  that  when  it  reaches  the  top  and  is  drawn  off,  it  is 
suitable  for  use  in  the  cylinders;  and  the  float-feed,  or  spraWng,  t\'pe, 
under  which  head  nearly  all  modem  devices  come.  The  others  have 
gone  out  of  use,  as  fuels  today  are  too  heavy  for  them  to  be  practicable. 

The  original  float-feed  carburetor  consisted  of  one  part  besides 
the  fuel  pipe,  float  chamber,  and  passage  to  cylinder,  which  made  it 
remarkable  for  its  simplicity.  It  had  no  adjustments,  nor  was  there 
any  way  of  securing  an  even  and  continuous  flow  of  fuel  or  of  air,  except 
as  the  engine  suction  produced  these.  The  need  for  these  qualities 
brought  out,  one  by  one,  the  modifications  of  the  original ;  and  through 
continuous  modifications  and  recombinations  of  these,  all  the  modern 
devices  have  been  developed. 

Defects  in  the  Orisinal  Are  Not  Found  in  Modem  Types.  The 
original  carburetor  had  no  adjustment;  the  opening  in  the  casting 
measured  the  amount  of  air,  while  the  size  of  the  nozzle  measured  the 
amount  of  the  fuel  and  the  fineness  of  the  spray.  There  was  no 
means  of  r^rinding  the  float  valve,  and  thus  no  way  of  assuring 
an  even  and  continuous  flow  of  fuel.  The  modem  adjuncts  of -the 
original  Maybach  device  consbt  of  remedies  for  these  defects,  and, 
in  addition,  a  proper  means  of  balancing  and  adjusting  the  float. 

To  pid(  out  a  modem  carburetor  at  random,  take  the  one  shown 
in  Fig.  81.    Like  its  ancestor,  it  has  a  gasoline  chamber  into  which 


G.4SOUXI:  AUTOMOBILES 


GASOLINE  AUTOMOBILES  103 

the  fuel  is  admitted  by  the  action  of  a  float,  when  it  first  passes 
through  a  strainer.  From  the  float  chamber  the  liquid  passes  up  to 
and  through  the  spraying  nozzle.  The  weight  of  the  float  is  so  calcu- 
lated that  the  level  in  the  final  nozzle  is  just  1  millimeter  (0.04  inch) 
below  the  top.  This  insures  that  there  will  always  be  fuel  there  for 
the  air  suction  to  draw  off.  As  the  physical  action  of  changing  a 
substance  from  a  liquid  to  a  gas  is  usually  accompanied  by  the 
absorption  of  heat,  it  is  advisable  to  supply  a  reasonable  amount 
of  this,  and  thus  assist  the  change  of  form.  In  the  older  May  bach, 
this  was  inadvertently  done  by  placing  the  whole  apparatus  in  close 
contact  with  the  hot  cylinder.  In  the  modern  carburetor,  placed 
some  distance  from  the  heated  portions  of  the  engine,  this  additional 
heat  is  supplied  by  the  jacket  water.  An  alternate  scheme  is  to 
pre-heat  the  air  supply  by  a  special  pipe  from  the  exhaust  manifold. 

From  this  mixing  chamber  the  mixture  of  air  and  gasoline  vapor 
passes  upward  into  a  secondary  mixing  chamber.  This  communi- 
cates with  the  inlet  pipe  through  the  medium  of  the  throttle  valve. 
The  auxiliary  air  supply,  when  used,  has  access  into  the  secondary 
chamber  through  the  auxiliary  air  valve.  This  comes  into  action  on 
ver>'  high  speeds  when  the  engine  is  pulling  very  strongly.  At  this 
time  the  proportion  of  gasoline  to  air  is  likely  to  be  too  large,  so 
the  auxiliary  opens,  admits  more  air,  and  thus  dilutes  the  mixture. 

Throttle  Valves.  Butterfly  Type.  Whatever  the  nature  of 
the  mixture  in  the  carburetor,  it  is  admitted  to  the  cylinder  by  the 
throttle  valve,  which  may  take  the  form  known  as  the  butterfly. 
This  is  a  flat  piece  of  sheet  metal,  preferably  brass,  attached  to  a 
suitable  shaft  with  an  operating  lever  on  the  external  end. 

Piston  Type.  Besides  the  butterfly  type  there  are  fully  as  many 
of  the  piston  type.  The  sliding  form  is  a  cylindrical  ring  or  shell  of 
metal,  which  is  free  to  slide  in  a  corresponding  cylindrical  chamber. 
In  the  walls  of  the  latter  are  a  number  of  apertures  or  ports  which 
the  longitudinal  movement  of  the  piston  either  uncovers  or  covers  as 
the  case  may  be.  Sometimes,  to  facilitate  this  action,  the*  sides  of 
the  piston  are  grooved  or  notched,  but  this  does  not  alter  the  prin- 
ciple of  sliding  a  cylinder  within  another  cylinder  to  cover  or  uncover 
certain  ports  in  the  cylinder  walls. 

In  addition  to  the  sliding  piston,  there  is  the  rotating  piston, 
working  in  practically  the  same  manner,  that  is,  its  rotation  connects 


104 


GASOLINE  AUTOMOBILES 


openings  in  the  piston  walls  with  the  interior  of  the  vaporising  chamber 
on  one  side  and  with  the  inlet  manifold  on  the  other,  the  amount 
of  the  opening  depending  upon  the  distance  the  piston  is  rotated. 
Needle  Valves.  Xeedle  valves — or  spray  nozzles  as  they  are 
sometimes  called  because  of  the  function  they  perform — constitute 
an  important  part  of  every  carburetor,  or  liquid -vaporizing  device. 
It  might  be  thought  that  so  long  as  there  is  a  hole  by  which  the  fuel 
can  enter  the  vaporizing  chamber  that  is  sufficient;  yet  such  is  far 
from  the  case.  In  addition  to  the  function  of  an  entering  hole,  the 
needle  has  the  additional  duty  of  breaking  the  fuel  up  into  a  fine 
spray  or  mist,  the  particles  of  which  are  easily  picked  up  by  the 
inrushing  air,  and  as 
easil\  converted  into  a 
\  apor  Therefore,  that 
shape  form,  or  arrange- 
ment w  hich  will  divide  the 
entering  liquid  up  into 
eJ  "  =  ^  the  finest  particles  will  be 
the  most  efficient.  The 
difference  of  opinion  on 
this     latter     point    has 


-t 


4Ji? 


Tit-  82.     Thp  F. 


GASOLINE  AUTOMOBILES  105 

to  vary  greatly,  both  as  to  quantity  of  fuel  flowing,  and  the  extent 
to  which  it  is  spread  out.  When  the  needle  is  down  very  low,  only 
its  point  enters  the  hole,  so  that  practically  the  full  area  of  the  latter 
is  available,  the  central  needle  influencmg  the  column  of  fuel  passing 
out  only  to  make  it  hollow  in  the  center. 

With  the  needle  raised  to  nearly  its  maximum  height,  however, 
the  point  projects  clear  through,  and  the  needle  shaft  almost  fills  the 
lower  part  of  the  hole.  This  reduces  the  flow  to  a  very  fine  hollow 
column  of  spray,  as  the  shape  of  the  needle  and  of  the  lower  edge 
of  the  hole  is  such  as  to  force  it  inward  and  then  outward  so  that  as  it 
leaves  the  top  of  the  hole  it  is  diverging  widely.  Thus,  the  effect 
of  the  addition  of  the  needle  is  to  allow  the  use  of  much  smaller 
quantities  of  liquid  with  the  same-sized  hole,  of  diffusing  it  more 
widely,  and  of  making  it  adjustable  to  varying  needs.  Despite  all 
its  advantages,  only  three  of  the  carburetors  and  vaporizers  shown 
use  this  type;  and  of  these,  one  is  a  combination  of  this  with  A. 

External  Needle  Type,  The  third  type  shown  at  C,  Fig.  82,  is  an 
inversion  of  B  in  that  the  needle  is  made  external  and  descends  from 
above  into  the  hole  in  the  nozzle.  In  this  form,  the  shape  of  the 
needle  point  produces  the  desired  diffusion  and  spraying  effect,  which 
accounts  for  its  popularity.  Of  the  models  shown  herewith,  nine  are 
of  this  kind,  one  being  a  modified  combination  of  this  form  and  A. 

External  Sectional  Needle  Type.  The  fourth  form,  shown  at*  D, 
is  like  C,  except  that  instead  of  a  needle  resting  upon  the  upper 
surface  of  the  hole  and  allowing  a  continuous  hollow  stream  of  fuel 
to  flow,  a  series  of  holes  break  up  the  column  into  a  number  of  very 
much  smaller  columns,  each  with  its  own  opening.  In  this  form  the 
central  member  may  be  movable  or  not,  while  the  holes  may  be  set 
at  any  angle.  Of  the  examples  of  this  form  shown  in  this  article, 
three  in  all,  every  one  has  the  holes  placed  horizontally  instead  of 
inclined  to  a  vertical,  as  shown  in  Fig.  82.  Of  these,  two  show  a  com- 
bination of  B  and  D,    This  is  an  effective  combination. 

Floats.  Another  feature  of  the  earlier  forms  of  carburetors, 
which  was  soon  found  to  be  in  need  of  a  change,  was  the  arrange- 
ment of  the  float.  In  Maybach's  original  vaporizer,  there  was  no 
means  of  balancing  the  float;  consequently,  there  was  no  way  of 
preventing  wrenching  and  breaking  of  the  needle-valve  spindle.  As 
this  disarranged  the  gasoline  supply,  it  made  a  change  very  important; 


106  GASOLIXE  AUTOMOBILES 

and  thu  proMem  rec«ivnl  eaHy  attention.  There  was  aUo  the  neces- 
«ity  for  reiUhle  devices  to  regulate  the  supply  of  air  and  of  gaiwline 
spray  fn^m  the  nozzle,  either  by  orij^nal  adjustment,  by  means  of 
a  governor,  or  by  effecting  a  constant  variation  by  hand  to  meet 
constantly  varying  conditions  of  mgine  demands. 

Thc:%  a/ldition.-t  to  the  on'ginal  form  caused  srane  trouble. 
The  ordinary  way  of  managing  the  balancing  of  the  Soat,  while  it. 
may  be  the  cause  of  trouble  at  times,  is  a  ver\'  simple  one.  The  float 
Li  of  exceeding  lightness,  whether  made  of  cork  or  metal.  With 
the  inflow  of  gasiiline  in  liquid  form  this  float  rises,  and  in  so  doing 
it  strikes  against  a.  pair  of  small  pivoted  levers  near  the  top  of  the 
flout  clianiber.  The  other  ends  of  the  pivoted  levers  rest  upon  a 
form  of  shifting  collar  on  the  needle-valve  stem.  So,  when  the  float 
rises  above  a  certain  level,  it  automatically  shuts  otf  the  flow  of 
ga.<u>line  by  pressing  against  the  pivoted  levers,  which,  in  turn,  act 
again^it  the  stem  and  press  it  down  until  the  flow  is  cut  off.  The 
float  will  stay  up  until  the  suction  of  the  engine  has  lowered  the 
gasoline  level  so  that  the  dropping  of  the  float  releases  the  levera 
which  raise  the  nwflle  valve  ofl^  its  seat.  The  gasoline  flow  ia  thus 
automatically  regulated  by  this  balance<l-float  arrangement. 


GASOLINE  AUTOMOBILES  107 

extracted  from  surrounding  objects.  This  accounts  for  the  frost 
which  gathers  on  the  outside  of  the  mixing  chambers  of  carburetors 
which  do  not  have  a  water  jacket  or  other  source  of  heat  supply. 
The  heat  is  abstracted  from  the  air  so  rapidly  that  the  moisture  in 
the  air  is  frozen,  appearing  as  frost  on  the  outside  of  the  carburetor. 

Auxiliary  Air  Valve.  The  auxiliary  air  valve  has  always  caused, 
discussion,  its  opponents  claiming  that  it  means  extra  parts,  and 
therefore  more  adjustments  and  more  sources  of  trouble;  while  those 
favoring  it  say  that  without  some  additional  means  of  this  sort  for 
diluting  the  mixture  at  high  speeds,  it  is  impossible  to  run  the  engine 
fast,  as  high  speed  will  then  mean  an  over-rich  charge.  Be  that 
as  it  may,  the  fact  remains  that  the  weight  of  opinion  lies  with  the 
auxiliary  valve. 

Necessity  vnth  Heavy  Fuels,  Practically  all  the  more  modern 
vaporizers  use  an  auxiliary  air  valve,  as  this  is  a  partial  necessity 
with  the  heavier  fuels.  That  is,  it  has  been  found  that  the  heavier 
fuels  require  more  air  to  vaporize  them  than  can  be  supplied  by  the 
primary  air  inlet.  Moreover,  these  heavy  fuels  require  considerable 
additional  heat  in  order  to  vaporize,  and  the  auxiliary  air  inlet  has 
been  made  the  vehicle  for  conveying  this.  As  will  be  explained  in 
detail  later  on,  this  is  generally  connected  with  the  exhaust  manifold 
in  such  a  way  that  the  air  entering  through  it  is  heated  to  a  high 
temperature.  Adding  this  after  the  fuel  has  been  split  up  by  the 
spraying  nozzle  and  the  primary  air  has  proved  very  successful. 

Usual  Forms  of  Auxiliary  Air-Inlet  Valve.  The  auxiliary  air 
inlet  usually  consists  of  a  simple  valve,  opening  inward,  held  in  its 
place  by  a  spring  of  a  certain  known  tension.  The  strength  of  the 
spring  is  carefully  determined  so  that  at  the  proper  moment — when 
the  motor  requires  more  air  in  proportion  to  the  amount  of  gasoline 
used — the  valve  will  open  just  enough  to  allow  the  required  amount 
of  air  to  enter.  It  will  be  seen  that  the  time  and  the  amount  of 
opening  will  be  controlled  by  the  speed  of  the  engine,  i.e.,  by  the 
amount  of  suction  produced  by  the  movement  of  the  piston  in  the 
cylinder.  Of  course,  as  the  engine  speeds  up,  there  is  a  greater 
piston  displacement  to  be  filled  per  minute,  and  therefore  it  is  neces- 
sary to  supply  a  greater  amount  of  mixture.  Upon  changing  speed 
suddenly  from,  say,  500  revolutions  to  900  or  1000,  the  carburetor 
which  does  not  have  this  device  will  no^  give  a  imiform  mixture  imme- 


108  GASOLINE  AUTOMOBILES 

diately;  in  fact,  it  might  require  a  new  adjustment  of  the  gasoline  flow 
in  order  to  supply  the  right  aaiount  of  fuel.  \Vliat  the  auxiliarj'  air 
inlet  actually  does,  then,  is  to  control  automatically,  above  a  certain 
point,  the  amount  of  air  admitted,  thereby  always  maintaining  a 
homogeneous  mixture.  In  order  to  prevent  any  chattering  of  the 
valve  or  rapid  changes  in  the  air  supply,  a  diaphragm  or  a  dashpot  is 
sometimes  used  in  connection  with  the  valve. 

As  a  substitute  for  an  auxiliar,^'  air  vahe,  a  number  of  makers 
have  tried  the  use  of  steel  balls,  resting  in  holes  about  two-thirds  the 
diameter  of  the  ball.  By  varying  the  size  and  weight  of  the  balls,  a 
truly  progressive  action  is  obtaine<l,  for  light  suction  lifts  the  light 
balls,  and  strong  suction  all  balls. 

Venturi-Tube  Mixing  Chamber.  Like  every  other  carburetor 
part,  the  spraying  action  and  the  shape  or  size  of  the  chamber  in 
which  it  takes  place  have  been  the  subject  of  much  debate.  Orig- 
inally, the  chamber  took  any  convenient  shape  and  varied  all  the 
way  from  a  pertectlj-  plain  cylindrical  shape  to  an  equally  perfect 
square,  with  all  the  possible  variations  in  between.  A  few  years 
ago,  however,  scientists  began  to  look  into  the  vaporizing  and  equally 
important  measuring  action  of  carburetors,  with  the  result  that  a 


GASOUNE  AUTOMOBILES 


In  water  meters  the  contracted  area  is  made  one-ninth  that  of  the 
pipe.  This  same  relation,  although  not  exact,  holds  in  the  case  of 
the  carburetor.  Since  the  area  varies  as  the  square  of  the  diameter, 
this  b  equivalent  to  saying  that  the  diameter  of  the  contraction 
should  be  one-third  the  diameter  of  the  full-sized  pipe. 

Double-No2zle  Type.    A  distinctive  design  of  two  connections 
leading  into  the  vaporization  chamber  is  the  Zenith  (French)  car- 


Fla-  83.    ZBnilh  Cu-bur«or,  Mod*!  ■O" 
Cnrtuy  q^  ^MilA  Carburetor  Company,  Detroit.  Mickiffan 

buretor,  a  diagrammatic  sketch  being  shown  in  Fig.  83.  This  is  biit 
a  modification,  in  a  way,  of  the  Venturi  plan,  for  the  latter  shape 
is  actually  used  for  the  vaporizing  chamber.  The  new  idea  consists 
in  leading  into  this  mixing  chamber,  two  tubes.  Of  these,  one  is  the 
ordinaiy  spray  nozzle  and  does  not  differ  from  that  used  on  hundreds 


no       .    "  GASOLINE  AUTOMOBILEa 

of  other  devices.  Tlie  second,  however,  is  very  different.  WhOe  it 
leads  into  the  same  mmng  chamber,  it  does  so  through  the  medium 
of  a  secondary  chamber,  or  standpipe,  to  which  the  suction  of  the 
engine  has  access.  If  this  suction  is  strong,  more  gasoline  is  drawn 
into  the  secondary  chamber,  from  which  it  may  enter  the  spraj- 
ing  zone. 

The  ordinary  nozzle  is  of  an  exact  size  and,  consequently,  can 
pass  only  a  certain  amount  of  fuel,  alwajs  at  the  same  speed.  With 
the  additional  nozzle,  this  does  not  hold;  and  being  of  large  diameter 
(comparatively),  the  flow  through  it  depends  wholly  upon  the  engine 
suction,  which  \arie9  at  all  speeds,  often  at  the  same  speed  upon 
different  occasions. 

Use  of  By-Pass.  This  matter  of  two  standpipes  has  a  parallel 
in  the  use  of  a  by-pass,  so-called,  around  the  usual  mixing  chamber. 
On  some  carburetors  this  is  made  so  as  to  allow  easy  starting,  the 
idea  being  tiiat  when  suction  is  applied  to  the  carburetor  by  cranking, 
with  the  throttle  closed,  practically  pure  gasoline  \apor  will  be  drawn 
through  the  by-pass.  This  will  start  the  engine  after  which,  as  the 
throttle  is  opened  gradually,  its  movement  cuts  off  the  b\'-pass,  until 
at  meiiium  speeds  it  is  out  of  use  entirely.     The  same  thing  applies  to 


OASOUNE  AUTOMOBILES  111 

simplicity,  has  brought  forth  a  general  simplification,  or  elimination 
of  inlet  pipes,  and  a  fairly  wide  use  of  horizontal  carburetor  outlets. 
The  latter  has  affected  carburetors  by  requiring  a  shorter  and  more 
compact  instrument,  with  a  side  outlet  and  a  vaporizing  arrange- 
ment which  will  produce  tolerably  complete  vaporization  in  a 
cttmparatively  short  distance.  To  a  certain  extent,  this  horizontal- 
carburetor  tendency  has  modified  existing  practice  in  nozzles,  \  enturi 
tubes,  interior  areas  and  arrangements,  etc. 

Effect  of  Heavier  Fuels.  The  growing  realization  by  carburetor 
manufacturers  that  the  increased  use  of  heavier  fuels  is  inevitable 
has  brought  forth  much  worthy  effort  in  the  way  of  vaporizing  them. 
This  has  temporarily  set  aside  the  kerosene  and  other  heavy-fuel 
vaporizers.  However,  as  the  fuel  is  bound  to  become  heavier  and 
heavier,  on  accoimt  of  the  excessive  demands  for  gasoline,  it  Is  only 
a  question  of  a  jear  or  so  before  kerosene  and  distillate  vaporizers 
will  be  agitated  again. 

Effect  (^  Vacuum  Feeds.  The  wide  use  of  vacuum  feeding 
devices,  combined  with  the  tendency  mentioned  above  to  clean 
and  simplify,  has  caused  a  much  higher  mounting  nf  carburetors. 
This  has  always  been  desirable,  but  hitherto  it  has  not  been  possible. 
The  vacuum  feed  for  the  gasoline  supply  has  made  this  change  pos- 
sible, while  the  cleaning  process  and  simplification  actually  forced  it. 

Effect  of  Motor  Changes.  The  high-speed  form  of  motor  now  so 
generally  being  adopted  has  had  a  big  influence,  as  have  also  the 
multi-cjlinder  forms,  both  creating  a  demand  for  greater  accelera- 
tion. Similarly,  starting  devices  have  forced  the  use  of  a  carburetor 
modification  by  which  instant  starting  is  possible.  These  require- 
ments have  called  for  new  designs,  smaller  and  lighter  parts,  more 
nearly  complete  automatic  actions  to  uncover  large  air  ports,  as  well 
as  other  improvements. 

Double  Cartniretors  for  Multi-Cylinder  Motors.  While  many 
eight-  and  twelve-cylinder  motors  have  but  a  larger-sized  plain  car- 
buretor, the  better  forms  have  a  double  device,  each  half  supplying 
a  group  of  cj'hndera,  and  the  halves  are  entirely  separate  and  distinct 
from  the  other,  except  for  a  common  fuel-supply  pipe.  Each  set  of 
cylinders  has  its  own  suction-actuated  nozzle  and  its  own  independent 
nozzle.  This  form  has  shown  its  worth  in  actual  use,  having  been 
verj-  successful  in  aeroplane  work  on  e^t-cyllnder  and  tweVve- 


112  GASOLINE  AUTOMOBILES 

cylinder  motors,  and  also  on  a  number  of  the  better  eight-  and 
twelve-cylinder  motor  cars. 

Multiple-Nozzle  Carburetors.  Another  development  brought 
about  by  this  demand  for  rapid  acceleration,  coupled  with  great 
maximum  capacity,  has  been  the  swing  toward  multiple  nozzles. 
As  has  been  pointed  out  on  previous  pages,  there  are  a  number  of 
carburetors  now  with  two  nozzles. 

• 

CARBURETOR  OPERATION  AND  ADJUSTMENTS 

Stromberg  Carburetors.  Fig.  81  shows  a  cross-section  of  the 
Stromberg  Model  "H".  Except  that  Model  "HA*'  has  a  water 
jacket  around  the  upper  portion  of  the  vaporizing  chamber,  the  two 
are  identical;  and  the  following  method  of  adjustment  for  Model 
"H"  will  apply  equally  well  for  Model  "HA'\  Similarly,  Model 
"HB"  uses  the  same  units  throughout,  and  is  of  the  same  design, 
but  differs  slightly  because  it  is  designed  for  a  horizontal  outlet.  This 
necessitates  turning  the  float  chamber  unit  out  at  right  angles  with 
the  other  chambers.  The  only  other  difference  in  the  two  forms  is 
that  Model  "HB*'  has  the  low-speed  adjustment,  marked  Primary 
Nozzle  Needle  Valve  in  Fig.  81,  threaded  so  that  it  works  in  the  reverse 
direction.  Otherwise  the  following  directions  apply  to  it  also,  and 
reference  will  be  made  to  this  single  difference  of  adjustment. 

General  Instructions,  Instructions  for  Models  **ir',  **H  A'*,  and 
"H  B".  The  float-level  adjustment  is  set  and  locked  at  the  factory. 
It  seldom  needs  readjustment.  Similarly,  the  air-valve  spring  adjust- 
ment is  set  and  locked  at  the  factory  and  seldom  needs  to  be  touched. 
There  are  but  two  adjustments;  that  of  the  primary-nozzle  needle 
valve,  which  controls  the  low  speed.  This  is  a  simple  needle  valve 
seating  on  the  inside  of  an  open  nozzle,  similar  to  Fig.  82  B,  the  open- 
ing of  which  is  usually  two  sizes  larger  than  is  ordinarily  necessary. 
This  permits  of  an  increase  in  fuel  flow  to  that  extent,  but  it  can  also 
be  shut  oflF  entirely.  If  the  carburetor  is  furnishing  too  rich  a  mixture 
at  low  speeds  as  indicated  by  "rolling''  or  **loading'\  turn  this  needle 
up,  or  anti-clockwise  (clockwise  on  Model  ^'IIB").  This  will  admit 
less  gasoline  and  make  a  leaner  mixture.  On  the  other  hand,  if  the 
mixture  is  too  lean,  turn  this  needle  down,  or  clockwise  (counter- 
clockwise on  **HB'').  This  will  admit  more  gasoline  and  make  the 
mixture  richer. 


GASOLINE  AUTOMOBILES  113 

The  second  adjustment  is  of  the  auxiliary  needle  valve,  which  is 
called  the  high  speed  because  it  controls  the  flow  of  gasoline  at  high 
speeds  by  regulating  the  time  when  the  secondary  needle  valve  begins 
to  open  and  add  its  quota  to  the  total  mixture.  If  the  running  of  the 
motor  at  high  speeds  indicates  too  lean  a  mixture,  advance  the  spark 
and  open  the  throttle  so  as  to  run  the  motor  at  a  fairly  high  speed,  but 
not  at  its  maximum.  Then  loosen  the  needle-valve  lock  by  means  of 
the  lock  screw  and  turn  the  needle  valve  up,  or  counter-clockwise, 
until  the  speeding  up  of  the  motor  shows  the  desired  result.  This 
should  be  accomplished  gradually,  giving  a  slight  turn,  noting  the 
speed  obtaiped,  adding  another  slight  turn  if  this  is  not  sufficient,  and 
noting  the  speed  which  this  gives.  Try  to  obtain  a  good  high  speed 
without  attempting  the  absolute  maximum.  When  the  mixture  is  too 
rich  for  good  results,  turn  the  needle  down,  or  clockwise.  When  the 
desired  result  is  obtained,  lock  the  needle  valve  in  place  by  means  of 
the  lock  screw. 

Preliminary    Adjustments,    Before    any    of    the    adjustments 
described  above  are  made,  it  is  assumed  that  the  motor  is  running  well 
and  is  in  good  condition  throughout.    Xhe  same  is  true  with  the 
carburetor,  except  for  a  slight  lack  in  richness  or  leanness  at  low  or 
high  speeds.    The  following  preliminary  steps  are  advisable:  Before 
starting  the  motor,  open  all  pet  cocks  on  the  carburetor,  so  that  the 
inflow  of  fuel  will  clean  out  any  dirt  or  sediment  in  the  packing  or 
elsewhere.    Set  the  high-speed  adjusting  nut  so  that  there  is  at  least 
)fSr-inch  clearance  between  it  and  the  needle-valve  cap  above  it  when 
the  air  valve  is  on  its  seat.    The  necessity  for  this  lies  in  the  fact  that 
I  the  needle  valve  does  not  begin  to  open  until  this  high-speed  adjusting 
!  nut  comes  into  contact  with  the  needle- valve  cap.     With  a  dashboard 
I  adjustment,  be  sure  that  the  rocker  arm  on  the  carburetor  to  which 
the  adjustment  rod  is  connected  is  not  in  contact  with  the  collar 
;   above  it  when  the  control  on  the  steering  post  is  all  the  way  down. 
Starting  Adjustments.    To  start  the  motor,  raise  the  steering-post 
control  to  its  highest  position.    This  produces  an  extra  rich  mixture, 
but  in  cold  weather  it  may  be  necessary,  in  addition,  to  close  the  air 
supply  in  the  hot-air  horn  (right-hand  figure  in  Fig.  81).    As  soon  as 
the  motor  has  started,  however,  this  should  be  re-opened.    As  the 
motor  warms  up,  the  steering-post  control  should  be  lowered  grad- 
ually.   If  the  carburetor  is  to  be  adjusted  at  this  time^  be  aur^  tk\& 


114 


GASOLINE  AUTOMOBILES 


steering-post  control  is  at  its  lowest  position  and  the  motor  thoroughly  1 
w&rnt. 

Changing  Nozzles.  WTiile  the  makers  equip  the  carburetors  at 
the  factory  with  nozzles  of  a  proper  aize,  there  are  times  when  peculiar 
or  unusual  conditions  seem  to  make  a  different  size  of  nozzle  nec'essi 
Before  changing  nozzles,  howe\'er,  the  ignition  sjstem  should  be 
checked  up  in  every  particular,  all  manifolds  and  valves  examined  for 
leaks,  and  all  other  contributing  factors  investigated  thoroughly. 
The  repair  man  can  judge  from  actual  conditions  when  a  change  is 
needed.  Thus,  when  a  normal  motor  in  good  condition  necessitates 
more  than  two  and  one-half  turns  of  the  primary  needle  valve  to  make 
it  idle  properh',  it  indicates  that  the  primary-  nozzle  is  too  small  and 
should  be  replaced  with  a  larger  one.  To  change  this,  take  out  the 
needle  valve,  also  its  stuffing  box.  Then  insert  a  long  screwdriver  and 
unscrew  the  nozzle.  Then  put  in  the  new  nozzle  in  the  same  way  and 
replace  stuffing  box  and  needle  valve.  Never  change  nozzles  by 
more  than  one  size  at  a  time.  The  opening  in  these  gets  smaller  as 
the  number  increases;  thus  No.  59  is  smaller  than  No-  5S.  If  a 
No.  59  is  not  large  enough,  cliange  to  a  No.  58  and  then  trj-  this 
out  thoroughly  before  proceeding  next  to  a  No.  57. 


GASOLINE  AUTOMOBILES  115 

izing  chamber.  In  such  a  case  it  is  advisable  to  take  the  matter  up 
with  the  Stromberg  Company  and  get  a  correctly  made  but  special 
air-valve  top. 

Stromberg  '*K**  Models.  This  company  also  makes  a  Model 
"K"  carburetor;  while  Model  "KO"  differs  only  in  that  the  attaching 
flange,  used  to  fasten  the  carbmretor  to  the  inlet  manifold,  is  tiurned 
at  right  angles.  Model  "KO-l"  is  similar  to  Model  *'K0",  except 
that  it  has  a  few  slight  modifications  which  enable  its  immediate 
application  to  the  Overland  car,  Model  81,  without  any  changes,  and 
to  other  Overland  Models  with  similar  ease.  The  illustration.  Fig. 
84,  shows  Model  "KO",  in  which  it  will  be  noted  that  the  general 
construction  is  very  similar  to  the  "H"  models,  except  that  the  float 
is  concentric.  This  saves  parts  and  manufacturing  cost  and  is  a 
low^er-priced  model.  There  is  an  idling  tube  which  runs  up  through 
the  middle  of  the  main  vaporizing  chamber,  and  the  needle  valve  is 
horizontal  instead  of  vertical,  but  otherwise  the  device  follows  stand- 
ard Stromberg  practice,  except  as  the  concentric  float  modifies  it. 

Adjusting  the  **X"  Models.  The  air-valve  adjusting  nut  cor- 
responds to  the  high-speed  adjusting  nut  on  the  "H"  Models.  This 
is  the  only  adjustment  of  the  "K"  Models;  the  stem  of  this  nut  sup- 
ports the  lower  end  of  the  spring  which  controls  the  air  valve  that 
opens  downward  into  the  air  chamber.  Turning  this  nut  clock- 
wise, or  down,  tightens  this  spring  and  admits  less  air.  This  produces 
a  richer  mixtiure.  To  obtain  a  leaner  mixture,  it  should  be  tiurned 
counter-clockwise,  or  up.  Before  starting  the  motor,  this  nut  should 
be  turned  counter-clockwise  to  a  point  where  the  lifting  of  this  nut 
results  in  a  slight  click  (the  air  valve  coming  into  contact  with  its 
seat).  Then  the  nut  is  turned  clockwise,  or  down,  notch  by  notch, 
until  this  click  is  no  longer  obtained.  Then  the  nut  should  be  turned 
two  full  notches  more. 

After  the  air  valve  has  been  set,  and  when  the  motor  has  been 
warmed  up,  this  nut  is  turned  one  notch  at  a  time,  in  either  direction, 
until  the  motor  idles  properly.  This  is  the  low  and  intermediate 
speed  adjustment.  High  speed  is  controlled  by  a  fixed  nozzle  and 
can  be  changed  only  by  replacing  this  with  a  different  size  of  nozzle, 
on  the  Model  "K".  This  is  done  by  unscrewing  the  pet  cock  at  the 
bottom^  inserting  a  screwdriver  and  unscrewing  the  old  nozzle.  The 
new  is  put  in  place  in  the  reverse  manner.    The  repair  paau  oa^  dt^\^X 


GASOLINE  AUTOMOBILES 


GASOUKE  AUTOMOBILES  117 

the  need  for  a  change  of  high-speed  nozzle  as  follows:  If  the  mixture 
on  high  speed  is  too  lean,  so  that  slightly  closing  the  dash-control 
valve  increases  the  speed,  then  a  larger  nozzle  is  needed.  If  the  high- 
speed mixture  is  too  rich,  a  smaller  nozzle  should  be  used. 

On  the  "KG"  Models,  the  nozzle  needle  valve  projects  from  the 
side  of  the  fioat-chamber  casting  at  right  angles.  With  the  motor 
varm,  the  spark  and  throttle  should  be  set  to  correspond  to  about 
twenty-five  miles  an  hour.  Tlien  this  needle  valve  is  turned  as  necesr 
sary  to  give  the  best  motor  speed. 

Zenith  Carburetors.  The  Zenith  Model  "O"  carburetor,  shown 
in  Fig.  83,  enjoys  wide  use  in  this  country  because  of  its  simplicity. 
It  has  fewer  ordinary  adjustments  than  any  other  carburetor.  This 
is  so  constructed  that  but  one  adjustment,  that  for  slow  speed,  is 
provided.  However,  its  makers  realize  that  sometimes  changes  and 
adjustments  are  necessary  to  secure  proper  results.  They  provide 
for  these  by  the  removal  of  three  internal  parts  and  their  replace- 
ment with  simpler  parts,  but  with  different  working  orifices, 
or  holes. 

Zenith  Adjuatmxnts.  The  three  parts  mentionetl  are:  choke 
tube,  main  jet,  and  compensator.  In  Fig.  83,  the  choke  tube  is 
marked  X.  This  is  really  an  air  nozzle  of  such  a  stream-line  shape 
(approximating  the  Venturi)  as  to  allow  the  maximum  flow  of  air 
without  eddies  and  with  the  least  resistance.  When  the  pick-up, 
or  acceleration,  is  defective  and  slow-speed  running  is  not  smooth, 
the  choke  tube  is  too  large.  In  this  case,  it  will  be  found  that  a 
la^er  compensator  I  does  not  better  the  situation.  Then  a  smaller 
choke  tube  is  needed.  This  is  held  in  place  by  a  screw  Xy  in  the 
choke  itself  with  a  lock  washer  to  prevent  its  jarring  loose.  To  remove 
the  choke,  the  butterfly  T  must  first  be  removed.  In  the  horizontal 
tv-pes,  the  body  is  in  two  pieces,  which  are  held  together  hy  an  assem- 
bling nut.  When  this  is  removed  and  the  two  pieces  taken  apart 
(the  bowl  from  the  barrel),  the  choke  can  easily  be  slipped  out  of 
the  barrel.  When  the  motor  will  not  take  a  full  charge,  that  is,  when 
it  cannot,  with  the  throttle  fully  opened,  this  indicates  the  need  for  a 
larger  choke  tube.  It  will  be  noted  that  although  the  pick-up  is 
good,  the  car  wUl  not  make  all  the  speed  of  which  it  is  capable.  In 
this  case,  take  out  the  choke  tube  X,  as  explained  above,  and  replace 
with  a  larger  one. 


118  GASOLINE  AUTOMOBILES 

Changing  the  Main  Jet.  The  main  jet  G,  Fig,  83,  shows  its 
influence  mostly  at  high  speeds.  Wlien  running  at  high  speed  on  a 
level  road,  if  the  indications  show  a  rich  mixture,  irregular  running, 
characteristic  smell  of  over-rich  mbrture  from  the  exhaust,  firing  in 
the  muffler,  sooting  up  of  the  spark  plugs,  and  low  mileage,  the  main 
jet  is  too  large  and  should  be  replaced  by  a  .smaller  one.  On  the 
other  hand,  when  running  at  high  speed,  if  the  indications  are  that 
the  mi.xture  is  too  lean,  if  the  car  will  not  attain  its  maximum  speed, 
if  there  is  occasional  back  firing  at  high  speed,  then  the  main  jet  is  too 
small  and  should  be  replaced  by  a  larger  one.  In  respect  to  back 
firing,  howe\er,  care  should  be  used,  as  this  is  more  often  due  to  large 
air  leaks  in  the  intake  or  valves  or  to  defects  in  the  gasoline  line. 

To  Replace  Main  Jd.  When  it  is  necessary  to  change  the  main 
jet  0,  Fig.  8i^,  to  a  larger  or  smaller  size,  the  lower  plug  L  is  removed 
first.  This  has  a  square  head  and  is  removed  with  a  wrench.  Then 
the  main  jet  is  unscrewed  from  below  by  means  of  a  screwdriver,  a 
notch  being  cut  into  its  lower  part  for  this  purpose.  In  reassembling 
care  should  be  taken  to  see  that  the  fiber  joint  packing  is  on  tlie  jet 
and  that  the  jet  is  screwed  up  far  enough  to  compress  this.  Otherwise 
jasoline  may  leak  around  the  threads.     But  one  fiber  washer  should 


GASOLINE  AUTOMOBILES  119 

• 

lower  surface.  In  connection  with  this  last  method  of  adjustment, 
the  makers  recommend  that  the  workman  should  start  with  the 
setting  provided,  then  proceed  to  determine  first  the  main  jet,  then 
the  compensator,  then  the  choke.  In  a  sense,  this  method  makes 
double  work,  for  any  change  in  the  choke  calls  for  a  corresponding 
change  in  the  main  jet,  but  it  gives  superior  results. 

ShuySpeed  Adjustment.     The  one  adjustment  in  the  Zenith 
device  which  is  really  an  adjustment  and  not  a  change  is  that  for  slow 
speed.    This  is  preferably  made  on  the  garage  floor,  with  the  motor 
properly  warmed  up.    When  this  has  been  done  and  it  has  been 
throttled  down  to  idling  speed,  any  irregularity,  such  as  the  lack  of 
ability  to  throttle  down  to  a  really  slow  speed  (say  350  or  less  r.p.m.), 
calls  for  a  change  in  the  adjustment.    When  the  throttle  T,  Fig.  83, 
is  nearly  closed,  there  is  considerable  suction  at  the  edge,  and  the  tube 
J  in  the  top  of  the  secondary  well  P  terminates  in  a  hole  A  near  the 
edge  of  the  butterfly  at  which  gasoline  is  picked  up.    If  the  motor 
will  not  throttle  down  as  slowly  as  it  should,  the  supply  of  gasoline 
can  be  reduced  bv  means  of  the  external  milled  screw  0.    When  this 
is  turned  in,  the  air  entrance  N  is  restricted,  and  consequently  a  richer 
mixture  is  drawn  in.    When  it  is  unscrewed,  or  turned  out,  a  larger  air 
opening  is  uncovered,  and  consequently  a  leaner  mixture  is  drawn  in. 
In  this  connection,  many  factors  other  than  the  correct  slow- 
speed  adjustment  of  the  carburetor  may  prevent  good  idling.    Some 
of  these  are:  too  light  a  flj^wheel,  too  much  spark  advance,  and  air 
leaks  created  by  (1)  poor  gaskets,  (2)  loose  valve  stems,  (3)  pitted  or 
scored  valves,  (4)  leaky  valve  caps,  (5)  spark  or  valve  plugs,  (6)  leaky 
priming  cups,  and  others.    Obviously,  if  any  of  these  faults  exist, 
no  amount  of  adjustment  of  the  slow-speed  device  on  the  carbiuretor 
will  give  good  idling. 

HorieorUcd  Type  AdjvMments  and  Changes.  Everything  that  has 
been  said  thus  far  applies  equally  well  to  the  horizontal  ty^  shown  in 
Fig.  85,  except  for  the  adjustment  of  the  idling  jet.  In  this  form,  the 
idling  jet  Pj  is  supported  by  the  kniurled  nut  0  which  governs  the  air 
opening  for  this  jet,  and  replaces  the  horizontal  milled  screw.  0. 
If  a  leaner  mixture  is  desired,  this  is  turned  to  the  right,  or  clockwise; 
this  lowers  the  jet  and  increases  the  size  of  the  available  air  passage. 
For  a  rich  mixture  it  is  turned  the  other  way,  or.  counter-clockwise, 
reducing  the  air  opening. 


120 


GASOLINE  AUTOMOBILES 


Float  Removal.  In  both  models,  it  will  be  noted  that  the  float 
cover  is  held  on  by  the  spring  catch.  This  is  lifted  by  means  of 
its  handle,  and  swung  around  out  of  the  way.  The  float  cover 
can  then  be  lifted  readily  by  means  of  the  knurled  edge.  When  this 
is  removed  it  should  be  lifted  up  straight.    The  float  is  then  exposed 


GASOLINE  AUTOMOBILES  121 

throttle  valves  are  mounted  on  the  same  shaft  and  work  in  unison. 
TTie  device  is  intended  for  eight-  and  twelve-cylinder  motors  and  is 
rigged  up  generally  with  a  pair  of  separate  inlet  manifolds,  one  for 
each  group  of  cylinders. 

Adjustments.    The  adjustments  on  this  double  Model  "O"  are 
the  same  as  on  the  single  Mode!  "O".     It  will  be  noted  that  the 

r 


slow-speed  adjustments  are  through  milled  headed  screws  0.  One 
of  these  projects  horizontally  on  each  side,  the  same  as  on  the  single 
model.  To  make  this  adjustment,  the  motor  should  be  started  and 
warmed  up;  then  the  spark  plugs  on  one  group  of  cylinders  are  dis- 
connected and  the  slow  speed  adjusted  for  the  other  set.  Then  the 
process  is  reversed,  with  the  other  set  of  plugs  disconnected,  and  the 
second  group  of  cylinders  adjusted. 


122  GASOLINE  AUTOMOBILES 

As  the  adjustment  is  changed,  a  difference  in  the  idling  should  be 
noticed.  If  the  motor  begins  to  run  evenly  or  speeds  up,  it  shows  that 
the  mixture  becomes  right  in  proportion,  but  that  there  is  too  much 
of  it.  This  is  remedied  by  changing  the  butterfly  throttle  position 
slightly,  closing  it  by  screwing  out  the  stop  screw  which  regulates  the 
closed  position  for  idling.  Care  should  be  taken  to  have  the  butterfly 
held  firmly  against  this  stop  at  all  times  when  idling  the  motor.  If 
the  single  group  of  cylinders  being  adjusted  seems  to  run  irregularly 
after  changing  the  position  of  the  butterfly,  another  adjustment  of 
the  knurled  screw  0  may  have  to  be  made.  After  one  group  of 
cylinders  has  been  made  to  idle  satisfactorily,  the  same  procedure 
should  be  repeated  with  the  other  group,  that  is,  each  half  of  the  motor 
should  be  adjusted  for  idling  independently  to  about  the  same  speed. 
The  single  thing  which  is  radically  different  and  must  be  remembered 
in  this  cormection  is  that  multi-cylinder  engines  have  very  light  fly- 
wheels and  reciprocating  parts,  so  the  motor  is  extremely  sensitive 
at  low  speeds  to  unequal  conditions  of  ignition,  compression,  and  air 
leaks.  This  makes  it  more  necessary  than  with  a  plain  four-  or  six- 
cylinder  form  to  have  the  motor  in  the  best  possible  condition  before 
changing  the  carburetor  idhng  adjustment. 

Carburetors  on  Ford  Cars.    On  the  Mtiilel  "T"  Ford  car. 


GASOLINE  AUTOMOBILES 


123 


tbence  out  to  the  motor  via  the  mixture  outlet  /.    In  this,  its  quan- 
tity is  governed  by  the  throttle,  the  lever  of  which  may  be  seen  at 
J.   In  the  air  intake,  there  is  a  throttle  plate  K,  which  deflects  a 
la^  part  of  the  entering  air  so  that  it  passes  to  the  right  (straight  in) 
and  .is  added  to  the  mixture  in  the  mixer  chamber.    This  forms 
the  auxiliary  air  valve.     The  position  of  this  plate,  governed  by  the 
auxiliary  throttle  lever  L,  determines  the  quantity  of  both  the 
primary    and    auxiliary 
sir,  since  by  its  position 
it  splits  the  entering  air 
into  two  parts,  one  of 
which  becomes  the  pri- 
mary air,  and  the  other 
the  auxiliary  air.     For 
low   speeds    and  idhng, 
the    low-speed    tube  M 
carries  the  very  rich  mix- 
ture    up    direct   to   the 
mixing  chamber  and  thus 
into  the  engine. 

Ford  Adjustment 
This  Holiey  model,  like 
the  Kingston,  has  butone 
adjustment.  The  needle 
valve  B,  which  has  a  pro* 
jecting  knurled  head  A 
for  turning  it,  has  a  con- 
ical point  C  which  seats 
mto  the  fuel  opening.  If 
this  is  seated,  no  gasoline 
can  enter,  but  as  it  is 
screwed  out  or  up  an  opening  is  created  and  increased,  which  allows 
fuel  to  flow.  The  amount  of  this  determines  the  amount  of  mixture 
entering  the  cylinder  combustion  chambers.  Consequently,  the 
primary  adjustment  with  this  screw  is  that  of  the  fuel  flow.  Air 
enters  through  the  opening  H,  passes  the  throttle  K,  and  then  mixes 
with  the  fuel  spray,  diluting  it  and  carrying  it  up  into  the  cylinders. 
The  funount  of  the  air  b  governed  by  the  air  lever  L,  its  position 


121 


G.\SOLIXE  AUTOMOBILES 


being  arlju-stetl  at  the  factor^-.    The  adjustmeots  as  recommeDded 
by  the  FonI  Motor  Company  are  as  follows: 

Initial  Adjustment.  The  usual  method  of  regulating  the  carbu- 
retor is  to  start  the  motor,  advance  the  throttle  lever  (on  the  steering 
wheel)  to  about  the  sixth  notch,  with  the  spark  lever  (also  on  the 
steering  wheel)  retarded  to  about  the  fourth  notch.  The  flow  of 
gasoline  should  now  be  cut  off  by  screwing  the  needle  ^-alve  down 
(to  the  right)  until  the  engine  b^ns  to  misfire;  then  gradually 
increa.se  the  gasoline  feed  by  opening  the  needle  valve  until  the  motor 
piclc*  up  and  reaches  its  highest  speed  and  until  no  trace  of  black 
smoke  comes  from  the  exhaust.  Having  determined  the  point  where 
the  motor  runs  at  its  maximum  speed,  the  adjustment  should  not  be 
changed  except  as  indicated  below, 
^-■-■'^  ~--^  Ffi-r  averagi^  results,  a  lean  mixture 
will  give  better  results  than  a  rich  o 

Dash  Adjustment.  The  gasoline 
adjustment  is  placed  on  the  dash. 
Fig.  H8,  the  mill«l  head  shown  being  ' 
fastened  to  a  long  rod  whose  lower 
I  end  is  attaclied  to  the  nee<lle  \'alve 
head    .1.    Fig.    S".     Any   movement 


GASOLINE  AUTOMOBILES 


125 


Oflier  HoUey  Carburetors.  Aa  has  been  stated,  the  carburetor 
illustrated  in  Fig.  87  and  just  described  is  a  Holley  Model  "G". 
Thisfinn  also  markets  a  Model  "H",  which  is  very  similar  to  the  "G", 
as  will  be  noted  in  Fig.  89.  The  biggest  differences  between  these 
modeb  are:  the  vertical  outlet  in  place  of  a  horizontal;  and  the 
placing  of  the  needle  valve  at  the  bottom  because  of  this.  In  this 
latter  figure,  fuel  enters  by  the  gasoline  pipe  through  the  strainer  A, 
past  the  float  valve  B,  into  the  float  chamber  D,  the  level  being 
t^ulated  by  the  movements  of  the  cork  float  C.  Prom  there,  it 
passes  through  the  opening  F  into 
the  nozzle  well  E,  through  the 
hole  H  past  the  needle  to  a  level 
m  its  cup-shaped  upper  end  which 
just  submerges  the  bottom  of  a 
nnall  tube  J,  with  its  outlet  at  the 
edge  of  the  throttle  disc  K.  When 
the  engine  is  cranked  with  the 
throttle  nearly  closed  an  energetic 
Sow  of  air  past  this  point  draws 
liquid  fuel  which  is  atomized  upon 
its  exit  from  the  small  opening  at 
the  throttle  edge. 

As  the  enpne  rotates,  consid- 
erable air  is  forced  to  move  through 
the  conical  passage  outside  of  the 
atrangling  tube  L.    The  shape  of 

ji  J   «i_      1  )  Fi«.  SO.     HoUey  CBrburetoi.  Model  "H" 

the  passage  around  the  lower  end         coi.rt«»  <./  noii,y  fl™i*<ri  coxpanv. 
of  this  is  such  that  the  entering  Dnrou.  nu^kxmt 

air  attains  its  highest  velocity,  and  thus  lowest  pressure,  near  the 
upper  end  of  the  standpipe  M.  Consequently,  there  is  a  difference 
a  pressure  between  the  top  and  bottom  of  this  pipe,  and  the  air 
lows  downward  through  the  series  of  holes  N.  At  the  bottom  it 
:unis  sharply  upward,  picks  up  the  fuel  spray  there  and  passes  into 
he  main  vaporizing  chamber  above  0,  and  thence  past  the  opened 
brottte  into  the  inlet  manifold  at  P. 

AdjustmeTii.  Aa  will  have  been  noted,  there  is  but  one  adjust- 
oent,  that  provided  by  the  movement  of  the  needle  valve  /.  When 
his  is  screwed  to  the  right,  or  clockwise,  the  valve  moves  upvaxd 


126 


GASOLINE  AUTOMOBILES 


and  reduces  the  size  of  the  fuel  opening.  When  turned  backward 
to  the  left,  or  counter-clockwise,  it  increases  tlie  opening  and  admits 
more  fuel.  The  effect  of  these  changes  in  its  setting  are  claimed  by 
the  maker  to  lie  manifest  equally  over  the  whole  range  of  the  motor. 
Acctirfling  to  the  maker,  this  desirable  feature  is  the  result  of  utilizing 
In  the  nozzle  action  the  pressure  drop  due  to  velocity  of  flow  rather 


GASOLINE  AUTOMOBILES 


127 


wann  mooths.  Ilis  oecesaitates  s  means  of  varying  it.  There  is  no 
bettN  source  of  heat  than  the  handy  exhaust  pipe  where  heat  is 
going  to  waste,  so  the  HoUey  device,  as  illustrated  in  Fig.  90,  utilizes 
the  exhaust  pipe  as  a  source  of  heat  and  leads  the  same  to  the  carbu- 
retor through  a  flexible  tube  with  a  r^ulating  valve  at  the  lower,  or 
carburetor  end.  This  is  regulated  by  a  simple  rod  connection  with 
a  small  handle  which  pro- 
jects through  the  dash  and 
has  a  dial  behind  it.  This 
ran  also  be  used  as  a  strang- 
hng  valve  to  assbt  starting, 
as  shown  above  at  A,  for 
hot-air  supply  m  winter,  as 
at  B,  for  half  cold  air  in  the 
spring  and  fall  months,  and 
for  all  cold  air  throughout 
the  summer -months. 

Kii^ton  Carburetcws. 
fncfojed  Type.    The  King- 
ston enclosed  type,  as  shown 
in  Fig,  91,  differs  from  the 
tj^pe  previously  shown  in 
that  the  auxiliary  air  valves 
in  the  form  of  various  sizes 
of  steel    balls    are    used. 
Heae  are  normally  seated, 
but  they  aie  lifted    from 
tbeir  seats  by  increased  suc- 
tion. The  primary  air  valve 
is  not    radically  different 
from  the  former  model,  but  the  passage   of    the   air    is    vertical 
rather  than  at  an  angle.    When  the  suction  lifts  the  ball  valves/more 
air  is  admitted.    This  joins  the  partially  vaporized  mixture  at  the  top 
of  the  vaporizing  chamber  and  completes  the  vaporization  and  dilution 
befwe  passing  the  throttle  valve  on  its  way  to  the  inlet  manifold.   Like 
the  model  previously  shown,  it  has  the  cup-shaped  needle  recess,  so  that 
when  the  motor  is  shut  off,  a  pool  of  fuel  collects  there;  this  makes 
starting  easy,  for  this  fuel  is  drawn  directly  in,  almost  without  ^utvoii. 


Kt-  «.     Pl»ii 

Cjirbuivtor 
ComrUtm  of  Bame.  Kittttton  t 
Kot^mo.  Man, 


128  GASOLINE  AUTOMOBILES 

Adjustments.  If  the  float  is  found  to  be  too  high  or  too  low,  it 
can  be  adjusted  readily  by  bending  the  float  lever  to  which  it  is  at- 
tached. The  oniy  other  adjustments  are:  the  setting  of  the  throttle 
which  governs  the  lowest  speed,  this  being  accomplished  by  the  screw 
shown  on  the  throttle-lever  arm  projection  at  the  left;  and  the  setting 
of  the  needle  valve  for  satisfactory  high  speeds.  This  is  accomplished 
by  unscrewing  the  cap  to  which  the  needle  is  attached  and  allowing 
more  fuel  to  flow.  Continue  until  the  highest  speed  is  reached  and 
passed,  then  turn  back  until  the  maximum  speed  is  reached. 


GASOLINE  AUTOMOBILES 


129 


fuels,  it  has  been  found  that  after  a  certain  time  the  engine  begins  to 

pound,  but  that  if  cooling  water  he  introduced  with  the  mixture,  the 

en^e  will  run  cooler,  and  this  pound  will  disappear.    To  remedy 

tius  is  the  function  of  the  water  valve. 

Adjustments.    Adjustments  and  repairs  for  this  model  will  be 

exactly  the  same  as  with  the  previously  described  enclosed  model, 

since  it  is  simply  two  of  these  joined  together.     As  has  been  stated, 

the  added  water  valve  works  automatically. 

Kingston  Model  "L,"    The  last  Kingston  model  shown,  that  of 

Fig.  93,  is  very  similar  to  the  Ford  model,  except  that  it  is  formed 

with   a    vertical   outlet,   and 

the  ur  valve  B  added  in  the 

vaporizing  chamber  so  formed. 

This  is  hinged  at  the  side  so  as 

to  be  swung  upward   by  the 

suction    of    the   motor,    thus 

uncovering  a  larger  and  larger 

orifice.    It    is    weighted    and 

acts  automatically.     It  will  he 

noted  also  that  the  shape  of  the 

nozzle  has  been  altered  slightly, 

that  on  the  Ford  model  being   I 

perfectly   straight.     Near    its 

lower  end,  it  passes  through 

the  low-speed  tube  C,  which  , 

has  a  series  of  holes  around 

the  bottom  and  an  annular 

space  around  the  body  of  the  needle.    Through  this  space  the  fuel 

and  a  very  little  air  are  drawn  for  starting,  as,  at  that  low  auction, 

the  valve  B  would  be  entirely  seated. 

Adjustments.  After  retarding  the  spark,  opening  the  throttle, 
loosening  the  needle,  and  starting  the  motor,  let  it  run  at  a  fair  speed 
long  enough  to  warm  up.  Then  adjust  the  needle  valve.  Close  the 
throttle  by  adjusting  the  stop  screw  in  the  throttle  lever  until  the 
motor  runs  at  the  desired  idling  speed.  Adjust  the  needle  valve  towards 
the  seat  slowly  until  the  motor  begins  to  lose  speed,  which  indicates  a 
weak  mixture.  Now  adjust  the  needle  valve  away  from  its  seat  until 
the  motor  attuns  its  best  and  most  positive  speed.    This  should 


'    Fie.  S3.     Section  o[  Kingston  .Model  "L"  Carburetor 
aurfiif  1^  Bgrm.  Kinj^m  and  Conpast, 


130 


GASOLINE  AUTOMOBILES 


complete  the  adjustment.  Close  the  throttle  and  let  the  motor  idle, 
then  jerk  it  open  rapidly.  The  motor  should  respond  readily.  If  it 
does  not  respond,  a  slight  further  adjustment  may  be  necessary. 
When  the  adjustment  has  been  made,  lock  it.  Float  troubles  may  be 
remedied  in  the  same  way  as  for  the  enclosed  model. 

Browne  Carburetor — One  Adjustment    An  entirely  new  idea 
iu  carburction  has  been  produced  in  the  Browne  carburetor,  which  is 


^J 

|BB Jj  HI  I 

a 

1 

G.VSOLINE 


>ntent3  erf  the  motor,  while  the  fiange  is  of  the  screwed-on 

that  it  can  be  made  of  a  size  to  fit  the  motor, 
^ond  this  radical  departure,  the  Browne  device  shows  another 
startling  innovation.  It  has  but  one  adjustment— the 
of  the  needle  valve  for  proper  fuel  supply — and  this,  once  set 
y,  need  never  be  changed  for  altitude  or  temperature. 
vtruetion.  To  explain  the  construction  which  allows  of  these 
epartures  from  ordinarj-  practice,  refer  to  Figs.  &4  and  95. 
■mer  shows  a  section  on  the  center  line,  and  the  latter  an 
I  view,  which  is  taken  from  the  opposite  side  to  that  of  Fig.  94. 
M  the  fuel  flows  from  a  float  chamber  P  of  conventional  design 
fuel  nozzle  by  a 

not  shown,  but 
■d,   in    Fig.   95. 

located  in  the 
if  a  Venturi  pas- 
ffith  a  30-degree 
h  and  a  7-degree 
;e.  The  area 
mall  and  insures 
it  velocities  at 
^speeds  to  atom- 
fuel.  Two  fac- 
idi  go  to  make 
QJecting  force  on 

nozzle  are:  the 
,  created  by  the 

.uction;  and  the  velocity  of  air  flow.  Both  of  these  are  made 
ipon  the  air  valve  E  in  this  device  by  introducing  the  vacuum 
r  F  beneath  the  vah'c  and  connecting  it  to  the  vaporizing 
r  by  the  opening  //.  In  this^a  ball  0  serves  as  a  valve, 
this  manner,  the  air,  at  any  veliicitj'  of  flow,  is  transmitted  to 
valve,  which,  through  its  position,  influences  the  amount  of 
y  air  admitted.  In  the  upper  part  of  the  carburetor,  it  will 
d  that  the  auxiliary  air  flows  in  through  the  openings  on  the 
ide  of  the  cover  B,  over  the  curved  bushing  C,  and  past  the 
Jges  of  the  air  valve  E,  to  the  mixing  chamber  1'.  Obviously, 
;ine  suction  is  transmitted  to  E,  so  that  both  forces  working 


on  the  nozzle  work  on  the  air  valve  as  well.  In  the  air  valve,  whidi 
is  made  of  aluminum,  the  curve  of  tiie  bushing  C  is  so  constructed  as 
to  always  admit  the  right  amount  of  air,  but  with  varying  velocities. 
This  b  an  important  feature,  for  air  valves  generally  are  considered 
to  open  too  far  at  high  speeds.  What  actually  happens  is  that  the 
velocity  is  reduced  too  low,  and  not  enough  fuel  flows.  As  pointed 
out  above,  this  device,  by  increasing  the  velocity  of  inflow,  overcomes 
this  defect. 

Waier-Jaek-efing.  Water-jacketing  on  this  device  is  a  necessity 
to  proper  and  continuous  operation,  hence  liberal  jackets  are  supplied. 
In  addition,  pre-heating  of  the  primary  air  is  considered  a  necessity, 
so  a  targe  hot-air  horn  is  supplied  at  K  for  the  attachment  of  a  hot-air 
connection  to  the  exhaust  manifold.  This  heating  Is  very  carefully 
set  down  by  the  makers  of  this  device  as  follows:  The  temperature  of 
circulating  water  is  practically  constant,  summer  and  winter.  Such 
heatsupplied to theoarburetorgivestwo things:  a  constant  tempera- 
ture of  the  fuel  passing  the  nozzle,  which  is  necessary  in  order  to  get 
accuracy  of  flow ;  and  a  rapid  evaporation  of  anj'  fuel  that  is  deposited 
as  a  film  upon  the  hot  walls,  which  thus  increases  the  economy  of 
the  device, 

Adjuating  the  linimifi.  As  has  been  stated,  the  Browne  has  but  a 
single  adjustment.  This  is  the  needle  valve,  the  projecting  milled 
head  of  which  can  be  seen  in  Fig.  95,  while  the  point  can  be  noticed 


GASOLINE  AUTOMOBILES 


133 


*el  C '  It  operates  on  the  constant  vacuum  principle.  This 
acuum  is  maintained  by  the  pressuredue  to  the  weight  of  the  valve  W. 
lis  valve  restsin  anannular  opening  with  its  seatEof  Veoturi  section, 
ut  the  actual  openings  are  a  series  of  holes  J  opening  onto  the  face  of 
lisehamberfi.  The  operation  iaasfollows:  Gasolineflowsinfromthe 
lel  supply  pipe  at  the  top  D,  then  downward  into  the  float  chamber  as 
Imitted  by  the  fioat  valve  0  which  is  attached  to  the  top  of  the  float 
.   From  the  float  chamber,  the  fuel  passes  through  radial  holes  Q  to 


e  well  at  the  bottom  G.  At  the  bottom  of  the  central  valve  N, 
a  nozzle  H,  through  which  the  fuel  is  metered,  or  measured, 
le  fuel  then  passes  up  through  a  central  oriflce  to  the  outlets  into  the 
aituri  at  J.  The  air  enters  through  the  flexible  tube  from  the 
haust  manifold  where  it  is  heated,  passes  into  the  outer  bowl  C 
me  it  circulates  around  the  fuel  in  the  float  chamber  and  heats 
at,  then  rises  around  the  sides  and  over  the  top  of  the  chambeT 


134  GASOLINE  AUTOMOBILES 

which  the  fupl  enters  completely  vaporize  it  and  iDtimately  mi 
witli  the  pre-heated  air.  Above  thi3,  the  enlarged  space  in  the  di 
B  gives  further  provision  for  the  intermingling  of  the  sirandgaso 
spray  before  it  passes  into  the  motor  through  the  horizontal  ou 
which  contains  the  butterfly  throttle  R. 

Adjustment.  The  amount  of  fuel  picked  up  is  controlled  by 
velocity  of  the  air  past  the  nozzles,  which,  in  turn,  is  govtmed  by 
sjK-ed  and  consequent  suction  of  the  motor.  Consequently,  a  pi 
tically  imiforni  mixture  is  maintained  throughout  the  entire  sp 
range,  accorfiing  to  the  makers.  The  central  portion  of  the  valvi 
is  expanded  to  form  a  piston  which  is  submerged  in  the  well  ful 
fuel  at  (1  and  tlien'bj'  prevents  the  fluttering  of  the  valve.  A  sii 
screw  A',  with  marked  locked  screw  L,  is  provided  for  adjustm< 
This  is,  in  el!re<-t.  a  stop  for  the  air  valve  and  operates  through 
me<liuni  of  the  clip  M,  the  inner  ends  of  which  fit  into  and  move  n 
the  air  valve  /'.    This  stops  the  downward  movement  of  the  val 


vAa.x< 


oi^ue  leading  to  the  inlet  manifold,  an 
below  it  through  which  the  air  enters,  hot- 

The  air  enters  from  the  right,  Fig.  97 
sage^  to  match  the  general  shape  of  the  c 
This  has  led  to  the  development  of  a  var 
the  air;  for  a  division  in  the  end  of  the  p; 
cold  air,  half  cold  and  half  hot,  or  all  hot,  a 
fuel  conditions  under  which  the  device  was 
arrangement  was  used.     Except  in  the  1 
would  be  most  desirable,  but  there  are  cc 
semi-hot  air  arrangement  would  be  best. 

Adjustment.  While  it  is  said  not  to  ha 
is  a  variation  which  corresponds  to  the  adj 
retors.  .This  is  the  air  damper,  which  is  a  louj 
ing  across  the  incoming  air  passage  parallel 
connected  by  means  of  a  Bowden  wire  me< 
lever  on  the  steering  post  in  the  position  wli 
adjustment  is  located.  When  this  is  moved, 
over  toward,  or  away  from,  the  distributor. 
or  increases  the  ieiir  passage  at  the  jets.  Wh 
so  as  to  restrict  the  passage  of  air,  its  veloc 
greater  suction  carries  up  more  fuel  from  fV 


111 


«  — •  1 


GASOLINE  AUTOMOBILES 


137 


ids  which  are  built  to  use  distillate  selling  at  6  cents  a  gallon,  in 
irel  lots.    This  fuel  has  a  specific  gravity  of  51  at  60°  F. 

When  made  for  Ford  cars,  this  device  has  only  11  nozzles.  On 
e  larger  sizes  from  14  to  19  are  employed.  The  use  of  this  device, 
.tb  its  vertical  opening,  necessitates  a  special  inlet  manifold  to  replace 
at  on  the  Ford  which  provides  for  a  horizontal  carburetor  outlet. 

Edwards  Carburetor.  A  decidedly  different  yet  most  interesting 
!vice  is  the  Edwards  carburetor,  made  by  the  National  Carburetor 
ompany,  of  Chicago.  This  is  shown  in  Fig.  98.  The  first  thing  to 
Ae  is  that  the  spray  nozzle  and  needle  valve  A  are  set  at  an  angle 
'  30  degrees  from  the 
irizontal.  In  addition, 
lis  forms  but  the  inner 
id  of  the  mechanism  by 
hich  the  nozzle  opening 
made  self-controlling, 
t  the  outer  end  is  a  bel- 
ws  chamber  with  a  col- 
paible  bellows  B  con- 
»ted  by  means  of  the 
lasage  F  to  the  mixing 
lamber  below  the  throt- 
.'.  In  this  way,  the 
essure  on  the  bellows  is 
irays  that  of  the  mixing 
amber.  The  shaft,  if 
might  be  called  that,  which  has  for  its  lower  end  the  needle  valve,  . 
piided  by  means  of  the  weighted  piston  C.  In  this  way  it  will  be 
ted  that  this  unit  governs  the  fuel  opening.  Note  also  that  the  air 
ters  at  />  on  a  curve,  and  that  the  piston  C  by  its  position  also 
verris  this  air  opening.  When  at  rest,  the  weight  of  the  piston  keeps 
Jown  so  that  it  is  but  A  inch  from  the  Jet,  the  latter  being  practi- 
Uy  cut  off.  This  gives  a  great  rush  of  air  at  the  start,  but  as  soon 
the  throttle  is  opened  the  pressure  in  the  mixing  chamber  falls,  so 
it  the  bellows  contracts,  drawing  up  the  needle  and  the  piston, 
IS  giving  more  fuel  and  air  at  the  same  time.  With  still  greater 
:tion,  the  [nessure  goes  even  lower.  This  device  will  itse  keioaeue 
<tily  if  the  air  enterinjr  Bt  D  is  pre-beated. 


C«.rt„t  0/  A 


are  there  any  other  variables. 

Sunderman  Safety  Carburetor, 
from  other  carburetors  in  several  respe 
like  shape  very  different  from  the  us 
pair  of  central  jets,  set  side  by  aide  in  tl 


air  enters  at  one  end,  and  the  mixture  t 
inlet  manifold.    The  fuel  enters  the  i 

Fi<r   P9  show«        TI.P  nmn.inf  !=  rf.«..lat. 


GASOLINE  AUTOMOBILES  139 

pressure  of  this  spring,  which  can  be  varied  at  will,  forces  the  rod  down 
against  the  air  door;  this  regulates  the  amount  of  air  which  can  enter. 
Beyond  the  jets  is  a  V-shaped  screen  against  which  .the  mixture  is 
thrown,  and  at  the  far  end  of  the  mixing  chamber  is  the  outlet  con- 
nection to  the  manifold  and  throttle  valve.  The  device,  it  is  claimed, 
will  feed  pure  combustible  gas  to  the  motor  from  cold  kerosene  or  gas- 
oline without  changing  the  adjustment  and  without  the  addition  of 
heat  through  hot-air  supply  or  hot-water  jacketing. 

Adjustments.  On  top  of  the  carburetor  will  be  found  a  projecting 
rod  1,  a  spring  container  2,  lock  nut  Sy  and  clamp  for  rod  4-  To  ad- 
just, take  hold  of  the  spring  container  2  with  the  right  hand  and  of  the 
lock  nut  3  with  a  wrench  in  the  left  hand  and  loosen  it.  Then  turn 
the  spring  container  to  the  left,  admitting  more  air.  Give  it  as  much 
as  the  motor  will  stand  without  popping  back,  then  tighten  the  lock 
nut.  Let  the  motor  idle  for  five  minutes,  then  open  the  throttle 
suddenly.  If  the  motor  loads  up,  loosen  the  screw  in  the  clamp  4  and 
raise  the  rod  1  a  trifle.  This  will  admit  a  little  more  air  when  idling 
and  prevent  choking.  These  are  the  methods  used  to  control  the  low 
and  high  speeds.  The  butterfly  throttle  lever  arm  carries  a  nut  and 
screw  5,  which  controls  the  distance  it  can  move.  It  should  be  turned 
to  the  left  for  a  low  throttle  and  to  the  right  for  a  higher  throttle. 
The  nut  forms  the  lock.  There  is  no  gasoline  adjustment.  As  the 
two  jets  are  screwed  in  from  below,  they  could  be  changed  if  desired, 
by  screwing  out  the  plugs  first  and  then  the  jets,  which  are  notched 
for  a  screwdriver.  The  V-shaped  screen  gives  the  device  its  safety 
claim,  for  the  flame  generated  in  back-firing  cannot  pass  back 
through  this. 

Longuemare  Carburetor.  The  device  which  bears  the  name  of 
this  famous  French  expert  is  now  made  in  the  United  States.  It  is 
of  a  modem  design  suited  to  American  conditions.  The  carburetor, 
as  shown  in  Fig.  100,  has  no  moving  parts  and,  beyond  two  settings, 
no  adjustments.  It  is  a  single-jet  t^^pe,  but  of  a  construction  which 
gives  the  benefits  of  double  jets,  one  central  and  vertical,  the  other 
ftnniilftr  and  opening  horizontally.  The  fuel  enters  from  the  gasoline 
line,  passes  through  a  strainer  and  through  the  openings  u  down  into 
the  float  chamber,  thence  through  the  openings  c  and  d  into  the  niavw 
fuel  diannel  A,  The  Bow  into  this  channel  is  controWed  b^  \\v^  xv'eft^^ 
valve  m  wbicb  is  adjusted  by  the  external  thumb  scww   M .   ^xsl 


i 


140 


GASOLINE  AUTOMOBILES 


filling  this  channel,  it  also  fills  the  narrow  vertical  passage  e  leading 
into  the  compensating  chamber  a,  and  fills  this  chamber  almost  to 
the  level  in  the  float  chamber.  At  the  other  end,  it  flows  up  the , 
smaller,  or  idling,  jet  j,  and  the  larger,  or  main  working  jet  i,  as  the 
fuel  rises  in  both  these  to  about  the  float-chamber  level. 

Operation.  In  the  closed  position  of  the  rotary  throttle,  which 
this  figure  shows,  the  fuel  flows  out  of  the  top  of  the  central  jet  into 
the  small  chamber  k  directly  below  the  throttle.     This  gets  its  air 


GASOLINE  AUTOMOBILES 


thit  it  takes  little  or  no  part,  as  the  volume  of  fuel  entering  through  it 
is  n^ligible  compared  with  the  great  quantity  entering  through  the 
main  jet.  The  very  strong  suction  on  the  main  jet  works  backward 
along  the  supply  line  until  all  the  fuel  is  drawn  from  the  vertical 
compensating  chamber  a,  when  additional  air  is  drawn  through  this 
from  the  air  holes  /  at  the  top.  This  vertical  passage  conveys  fuel 
to  the  vaporizing  chamber  when  the  throttle  is  opened  and,  later,  air 
as  the  motor  is  speeded  up.    The  air  must  pass  through  the  fuel 


Tw,  101.     Eilcru]  View  of  the  Loncuemnre  Cnrburctoc.  Showing  Adji 


diannel  k  and  the  jet  t,  so  that  it  helps  to  break  up  the  fuel  and  form 
a  gas  before  the  jet,  which  usually  performs  this  function,  is  reached. 
I^e  saturated  gas  discharged  from  the  working  jet  is  further  diluted 
by  the  large  volume  of  air  rushing  through  the  main  air  entry  x. 
AdjiutmerUa.  There  are  two  settings  to  be  made,  after  which  the 
LoDguemare  needs  no  adjustment.  With  these  two  settings^made  to 
the  satisfaction  of  the  operator  of  the  car  or  motor,  the  device  is 
entirely  automatic.  There  are  no  jets  to  change,  no  dash  or  steering- 
post  adjustments,  and  no  changes  to  make  for  differences 4n  tempera- 
ture and  altitude.  The  adjustments  or  settings  are  (1)  for  starting 
and  idling,  and  (2)  for  speed.    They  are  independent  of  each  other, 


iStarting  and  Idling  Adjustment.     R 
starts  with  the  throttle  closed,  so  make  c 
ing  on  this  adjustment.     In  this  close( 
A  A,  Fig.  101,  rests  against  the  set  sci 
on  the  side  plate.     In  the  full  open  pos 
the  lug  L  on  the  other  side  of  the  plate, 
screw  R  on  the  left  side  of  Fig.  101  (r  ii 
adjustment  for  idling  and  starting  and  sh 
turns  from  its  fully  closed  position.     ^ 
turn  the  motor  over.    When  the  mote 
slightly  to  allow  the  njotor  to  warm  up, 
motor  stops,  turn  in  the  throttle  set  sere 
one  turn  to  give  more  throttle  opening, 
try  turning  the  screw  P  in  until  the  motor 
Now  turn  in  the  thumb  screw  R  one  nol 
each  turn  to  get  the  full  effect.     Contini 
idling  is  obtained.    This  completes  the 
ment;  and  when  this  is  done  in  a  thorough 
finished  for  that  motor  for  all  time. 

Speed  Adjustment,  All  speed  adju^r 
the  ratchet-locked  thumb  screw  M  on  top 
which  is  covered  by  the  removable  guai 


11 


GASOLINE  AUTOMOBILES  143 

and  if  the  motor  stalls,  give  more  fuel  by  again  turning  the  screw  M 
out  a  notch  at  a  time.  This  adjustment  should  be  followed  through 
very  carefully  and  slowly,  and  eadi  adjustment  tried  out  after  it  is 
made.  Finally,  if  the  faulty  motor  action  cannot  -be  corrected  in  this 
manner,  it  is  usually  a  sign  that  the  choke  tube  is  too  lai^  and  it 
should  be  replaced  with  a  smaller  one. 

Changing  Choke  Tvbes.  Remove  the  two  acom  nuts  Z;  discon- 
nect the  fuel  line  from  the  float  chamber,  after  turning  off  the  fuel; 
then  the  float  chamber,  groiip  B  complete,  can  be  removed  from  the 
mixing  chamber,  group  S,  which  is  attached  to  the  inlet  manifold. 
This  removal  will  expose  the  choke  tube  in  the  lower  end  of  the  mixing 
diamber,  where  it  is  held  by  the  set  screw  C,  located  just  below  the 
idling  adjustment.  Loosen  this,  and  the  choke  tube  (marked  L  in 
Fig.  100)  can  be  removed  and  replaced  by  another.  The  makers 
advise  the  purchase  of  two  additional  choke  tubes  with  each  carbu- 
retor, one  larger  and  one  smaller  than  that  in  the  instrument.  As  a 
rule,  the  medium  size  of  tube  should  be  tnetl  out  first,  but  if  this  does 
not  give  perfect  adjustment,  the  others  may  be  tried  out  on  the -road. 
INTien  this  change  has  been  made  and  the  two  previously  described 
adjustments  are.  complete,  there  is  no  further  need  for  varying  the 
carburetor,  as  once  made,  these  settings  take  care  of  all  temperature, 
alUtude,  and  other  changes,  including  seasonal  variations, 

Webber  Automatic  Carburetor.  The  Webber  carburetor  has 
been  produced  to  meet  the  need  for  a  very  finelj-  and  carefully  made 
instrument.  It  is  an  instrument  of  precision  and  is  priced  accord- 
ingly. Two  models  are  made,  namely,  Model  "C",  which  has  a 
vertical  outlet  and  water  jacket;  and  Model  "E",  which  has  a"  horizon- 
tal outlet  and  no  water  jacket  and  is  therefore  smaller  and  more  com- 
pact. With  these  exceptions,  the  two  are  very  similar  in  construction, 
as  well  as  in  adjustment  For  this  reason  only  the  Model  "C"  will 
be  shown.  This  will  be  seen  in  Fig.  102,  which  shows  a  longitudinal 
section  along  the  center  line  of  the  two  chambers.  It  will  be 
noted  that  this  device  has  a  concentric  float  3?  in  which  the 
spray  nozzle  35  is  located.  The  needle  point  32  is  controlled  through 
the  needle-point  lever  IS  which  works  down  onto  it  from  above. 
The  nozzle  is  placed  in  the  center  of  the  modified  Venturi 
chamber  7,  the  top  outlet  of  which  consists  of  a  series  of  10  tapered 
boles.    As  the  fuel  mixed  with  the  hot  air  entering  through  the  air 


GASOLINE  AUTOMOBILES 


up  the  partly  vaporized  fuel.  In  this  upper  cylindrical  vaporizing 
chunba  St  the  throttle  valve  18  of  the  simple  butterfly  type  is 
located. 

TTie  auxiliary  air  enters  through  the  holes  60  below  the  dashpot 
chamber  S  in  which  the  piston  S  is  located.  This  is  attached  to  the 
upper  end  of  the  auxiliary  air-valve  stem,  its  lower  part  having  a 
conical  extended  shape  so  as  to  spread  out  the  air.  The  dashpot 
]vevents  fluttering  while  the  downward  movement  of  the  air  valve 
is  re»sted  by  the  spring  34.    The  tension  of  the  spring'is  adjustable 


ng.  103.     Gitamal  Vise  of  Wcbtwr  Cuburetoc,  Showinc  Adiiutnunta 

by  means  of  the  milled  thimble  28  and  the  locking  plunger  30.  The 
air-valve  lever  11  b  interconnected  with  the  needle-valve  lever  IS, 
so  that  any  movement  which  increases  the  air  opening  automatically 
increases  the  fuel  flow  also,  and  vice  versa. 

Adjusting  the  Webber.  There  are  two  adjustments,  aside  from 
the  setting  of  the  air  valve  and  the  determination  of  the  proper  needle 
valve  and  its  correctly  proportioned  spring.  These  are  for  low  speed, 
or  idling,  and  for  high  speed,  or  maximum  power.  Assuming  that 
the  carburetor  has  been  installed  correctly  and  the  fuel  turned,  on., 


%tM.  \^   V  \^\t 


r>e  sure  that  when  the  levt 
(handle  operating  Bowden  wire)  is  move 
the  lever  F  on  the  carburetor  is  pressed  fo 

Low-Speed  Adjustment.     Move  the 
to  the  rich  position,  open  the  throttle  al 
the  motor.    Now  move  the  lever  on  the  st 
to  the  lean  position  and  allow  the  motor 
warmed  up.    If  it  does  not  idle  properly,  t 
screw  A  up  or  down  until  it  runs  smoott 
against  the  stop  screw  Z>.    The  latter,  aft 
should  be  fastened  by  setting  up  the  clan 
purpose.    This  adjustment  is  for  idling  onl 

High-Speed  Adjustment.  The  high-s 
by  turning  the  screw  B  to  the  left  or  right 
block  E  in  or  out;  moving  it  in  gives  less  g 
moving  it  out  gives  more  gasoline  at  high 
can  be  made  with  the  motor  standing  and  c 
to  be  the  best  position  is  reached ;  but  th 
ment  should  be  made  on  a  long  hill.  On  thi 
at  about  20  miles  per  hour,  open  the  throttl 
at  the  top.  Now  go  down  the  hill.  After 
E  out  about  ^  inch,  try  the  hill  a  second  ti 
torn  at  thp  Qorno  o,^^-  « 


GASOLINE  AUTOMOBILKK 


147 


tbe  point  of  maximum  power;  as  tills  point  means  maximum  speed, 

Seiibilit.v,  and  acceleration. 

Starting  Adjustment.    The  makers  claim  that  it  i»  unnecessary 

vhm  the  proi)er  adjustments  have  l>cen  maric  to  wait  for  the  motor 
towarm  up  before  starting  away;  simply  mo\'e  the  steer! ng-<:(ilunm 
control  to  the  rich  position,  start  the  motor.  aii<i  drive  olT,  then,  as  the 
motor  warms  up,  move  this  contn)l  lever  down  toward  the  lean  posi- 
tion, running  normally  with  this  as  far  down  toward  loan  as  it  will  go. 


1, 

1 

k. 

CONSTANT   A 
OPENING 

R 

i^y 

! 

1 

SPfej  "•^'"'  1 

^^yj 

i 

1 

b 

MODEL  G        ' 

li        [dash  pen 

■flft      I    PISTON 

▼^1  ' 

1 

1  "isjtr  I^JEl, 

|»;„i.| 

Lawi 

r  Air  V.lve 

Except  that  some  of  these  ailjusting  s<Tews  arc  lorated  differently, 
the  adjustment  of  the  Model  "K"  is  the  same  an  thiit  of  Mo<!el  "('", 
as  is  also  that  of  the  Model  "E  H"  a  miKlificatiiin  of  the  "K"  wlapted 
particulariy  to  the  Hupmobile. 

Rayfield  Carburetor.  The  Uayficlil  carburetor,  Mcnlel  "G",  as 
shown  in  Fig.  11)4,  is  of  the  double-needle  tyiw,  with  three  air-inlet 
openings  and  an  eccentric  ilf>nt  chamber.  The  latter  is  shown  at  the 
left,  with  fuel  entering  from  heliiw  through  a  strainer.  Communi- 
cating directly  with  this  float  chamber  Is  the  passage  in  which  the 
low-speed  nozzle  (marked  spray  nozzle)  Is  situated ;  this  consists  of  a 
Jiollow  member  with  the  actual  newUe  point  coming  dmvn  veT^]\«ji\\\>- 


148  GASOLINE  AUTOMOBILES 

from  outside  and  above,  simitar  to  C,  Fig.  82.  Commumcating  with 
the  float  cliamber  is  a  passage,  or  well,  through  which  fuel  flows  across 
to  the  bottom  of  the  high-speed  well.  In  this  passage  is  located  a 
hollow  metering-pin  nozzle;  and  in  the  upper  part  of  it  is  the  meter- 
ing pin.  The  upper  end,  through  which  the  fuel  flows,  is  located  in 
one  end  of  the  elongated  vaporizing  chaniber,  while  the  upper  auto- 
matic air  valve  has  access  to  the  top  of  it  and  furnishes  the  air  supply. 
At  the  otlier  end  of  the  vaporizing  chamber  the  idling  needle  is 
located,  and  directly  beyond  it  is  the  constant  air  opening,  a  simple 
round  hole  communicating  with  the  atmosphere.  This  end  is  short 
and  close  to  the  central  portion  of  the  chamber,  which  is  approxi- 
mately cylindrical.  The  lower  air  valve  is  at  the  bottom.while  the 
vertical  connection  to  the  inlet  manifold  and  the  butterfly  throttle  are 
at  the  top.  The  lower  air  valve  and  the  upper  automatic  air  valve  are 
linked  together  so  as  to  operate  simultaneously.  The  movement  of 
the  upper  automatic  air  valve  downward  actuates  the  metering  pin, 
moving  it  downward;  this  tends  to  allow  fuel  to  flow  out  around  the 
pin.  At  the  same  time,  the  stem  of  this  valve  is  connected  at  the 
bottom  with  a  piston  working  in  the  dashpot  which  is  filled  with  fuel* 
so  that  any  sudden  tendency  for  the  air  valve  to  open  is  checked  by 
this  <l;tshin)t.     .At  llie  snnie  tiiin'.  tiiis  nistcui  cinninnnicutes  with  the 


GASOUNE  AUTOMOBILE!? 


149 


Alwaj-s  adjust  the  carburetor  with  this  dash  control  down.  The 
W-speed  adjustment  should  be  made  first.  To  make  this,  close  the 
throttle  and  let  the  dash  control  down,  then  close  the  nozzle  needle 
V  turning  the  low-speed  adjustment,  Fig.  105,  to  the  left  until  the 
block  U  leaves  contact  with  the  cam  M  slightly.  -  Then  turn  to  the 
rirfit  about  three  full  turns.  Start  tlie  motor  and  allow  it  to  run 
until  warmed  up,  then  push  the  dash  control  all  the  way  down,  retard 
the  spark,  close  the  throttle  until  the  motor  runs  slowly  without 
■'topping.  Now  make  the  final  adjustment  by  turning  the  low-speed 
■^■rew  to  the  left  until  the  motor  slows  down.     Next,  turn  to  the  right, 


high  speew 
adjustment! 

TO  RIGHT 


Fil.  103.     Eitcmat  View  ot  llayGrld  Corburr-lur,  Mudcl  "C".  .Sliuivinfi  Adjuitinenti 

'  one  notch  at  a  time,  until  the  motor  idles  smoothly.  If  the  motor 
does  not  throttle  low  enough,  turn  the  stop-arm  screw  on  the  main 
throttle-valve  shaft  to  the  left  until  the  motor  does  run  at  the  mini- 
mum speed  desired. 

High-Speed  Adjustment.  Advance  the  spark  about  one-quarter 
*ith  the  motor  running,  then  open  the  throttle  quickly.  Should  the 
motor  back-fire,  it  indicates  a  lean  mixture.  Correct  this  by  turning 
the  high-speed  adjusting  sctcw,  Fig.  105,  to  the  right,  about  one  notch 
■t  a  time,  until  the  throttle  can  be  opened  quickly  without  back-firing. 
If  loading,  or  choking,  is  experienced  when  the  motor  is  running  uw\« 


150 


GASOLINE  AUTOMOBILES 


heavy  load  with  the  throttle  wide  open,  it  indicates  too  rich  a  mixture. 
This  can  be  overcome  b,\-  turning  the  high-speetl  adjiistment  to  the 
left.  Adjustments  made  for  high  speed  will  not  affect  low  speed. 
Low-speed  adjustments  must  not  be  used  to  get  s  correct  mixture 
at  high  speed.     Both  adjustments  are  positively  locked. 

Changing  Noxzles.  "Never,  under  any  circumstances,  chai^S' 
nozzles  in  theModeis  "G"  and  "L"  carburetor,"  say  the  manufacturers. 
Neither  should  the  float  level  be  changed,  as  they  say  this  is  correctly 
set  at  the  facttiry  and  should  not  be  touched.  For  use  with  a  pres- 
sure system,  two  pounds  pressure  is  advised.     The  plugs  S,  1,  and  X 


Note  Lt^uid  H/e'  Dra'"< 
/Oamfoldb^SuCliCr  of  Mo/or 


GASOLINE  AUTOMOBILES  151 

s&id  above  on  tbe  subject  of  adjuatiag  the  "G"  applies  with  equal 
^  force  to  the"L". 
^  AdjasUng  Model  "M".    The  Raj-field  firm  makes  another  model, 

knon'n  as  Model  "M",  which  is  similar  to  the  Model  'T.",  except 
that  it  has  a  side,  or  horizontal,  outlet.  It  has  the  same  two  adjust- 
ments, made  in  the  same  way,  but  the  shape  of  the  carburetor  locates 
these  in  a  ditTerent  place.  The  low-^speed  adjusting  screw  is  on  the 
extreme  top  of  the  carburetor,  and  the  high-speed  adjusting  screw 
is  also  on  the  top,  but  it  is  made  accessible  by  removing  the  hot-air 
elbow  from  the  main  air  \'alve.  This  model  is  fitted  with  a  starting 
primer  incorporated  in  the  device  itself  and  operated  through  the 
medium  of  a  dash  lever.  In  the  sketch,  Fig,  lOG,  which  is  self- 
CKplanatorj',  the  construction  and  operation  of  this  are  shown.  When 
pressure  feed  is  used,  not  more  than  one  pound  is  recommended  for 
Model  "M".  WTien  the  startingprimer  is  to  be  attached,  the  following 
method  should  be  used:  Locate  the  position  on  the  dash  desired  for 
the  push  button  and  drill  a  |-inch  hole  at  the  proper  angle.  Attach 
the  adjustment  and  run  the  tubing  to  the  bracket  on  the  carburetor, 
avoiding  sharp  bends.  Cut  off  the  tubing  so  it  will  extend  beyond 
the  bracket  not  more  than  \  inch.  Remove  the  temporary  wire 
from  the  carburetor,  insert  the  tubing  and  secure  permanently  by 
tightening  the  clamp  screw.  Run  the  dash  adjustment  wire  through 
the  hole  in  the  binding  post  on  the  eccentric  lever.  Then,  with  the 
push  button  down,  place  the  eccentric  arm  in  position  so  that  the 
line  on  the  eccentric  just  comes  in  contact  with  the  adjusting  screw. 
Tighten  the  screw  in  the  binding  post,  cut  off  the  surplus  wire,  and, 
without  changing  the  position  of  the  push  button,  make  the  carburetor 
adjustment,  as  previously  described. 

Ball  and  Ball  Carburetor.  The  Ball  and  Ball  device  has  been 
developed  by  Frank  H.  and  Frederick  O.  Ball  and  is  named  after 
them,  but  it  is  manufactured  and  sold  by  the  Penherthy  Injector 
Company.  In  all  its  forms,  as  used  on  a  number  of  different  cars, 
whether  single  or  double,  horizontal  or  vertical,  it  is  a  two-stage 
instrument.  These  two  stages  are  called  the  primary  and  the 
secondary.  As  shown  in  Fig.  107,  the  primary  stage  corresponds  to 
the  usual  simple  air-valve  carburetor.  This  consists  of  nozzle,  or 
jet,  3,  located  in  the  fixed  air  passage,  or  Venturi,  2.  In  the  passage 
above  this,  it  receives  its  air  for  complete  vaporization  from  the 


-    I-.-  vaiuuretor  ad<l  i 

nozzle  0  and  of  the  air  supply   T,  wliid 


,  './  /V  nfcrrti^  I  •,:,<■!•« 


fra^  tfap  saaae  bcuriKmuJI  pftssuv-  :'  s^  3w»  t^  ftnaaay  jn. 
If  tte  xlmndF  W  -occoKKiHid  -up  Ti»  i^  v-idif?  i^in-orV  ic  fiwii  a  v:^- 
that.  TJisD  aji^mnKiiiitc  lirf  nmLJima  corrinc  I'f  7^  ttuui:  l^wnilr. 

irurc..  «se  ■»\-«iiai:  ctk-  ibr  li--flnfT  njipt,  -^y<h  c.^ts-  O'wJ  i.ffirtf 

adjisz  its  tixaii  tS*a  tj>  ihxi  <rf  the  •;vimij\\    Thf  TTr,>  oi-cTrfciicT.ir^' 

due  ptvtjoftti  bj  -w+ikj  b-  is  «^<«-^,  i  liivjitvV  oir^ii^w^.ir,    T>;i?v 

nh  rtiiMaaEi~  foe  i-:ajii'fli>  sar>  ntd  i?"pr?  iif  c»j^  i-vcjiiiT:;:!!?:?-  zhf  HsW 
»»)  Ball  JeiToe.  Actt  ia  iih.Tii'flj  ir;  Fit.  '. '.C, 

producrs  renurkahir  artv^efarxyD.  TV.i>  rt'^r.s;*:?  --f  liie  -."iJ-^njprr  -"" 
hail-in^  «  anafifr  aofti  opt*?  «>ii  -.  i:  :<  kv«*S  a:;rti :-  tSe  .-^jbti- 
W  IS,  tht  bonco  «rf  wikii  ivromunk-ai^  with  tr*  Awt  (-^MUi^Ser. 
utd  is  thus  kcfft  foQ  fi  Caroline.  At  the  t>^.  a  ^nutli  ht-iio  :  '  <.\«iniu- 
Duates  wiih  tbp  manifotd  abo'*"*  llw  xhn>nie,  while  : .'  i*  a:i  .>|>e;'.i!\s 
to  the  atmospbere.  aoJ  ;?  i*  an  opeairj;  l<*  ifce  miwHi:  (-hamher, 
^Vbra  tbe  throttle  is  nearly  ck>?*e(l.  ihe  \~aouuiu  in  the  mani^>kl 
ni^«s  tbe  plunj^er.  and  tbe  space  bek>*r  it  lilb  *rtih  ,ca~^^iiie.  lii  this 
pft^ilioo  h  is  ready  to  act,  Wlien  the  tht\>ttle  is  «^>eiH\l  sih),i»>r.Ix . 
the  vacuum  b  broken,  and  the  plun£er(it\)|>s(^it^  own  «-vi^t.  fomiu: 
tbe  gasoline  up  vbete  it  is  swept  into  the  mi\inf:  I'haniK-T  by 
the  air  entering  throi^^  the  passages  :i  and  J^.  This  is  ■vineaml  as 
often  as  tbe  throttle  is  suddenly  openetl  fmni  a  nearly'  I'losvxl  |>osition. 
Adjurtfnrntt.  The  primary  stage  must  be  atljusted  as  a  whoto 
topve  the  best  idling  and  slow  speetls:  thisivnsistsof  ibeailjnstnKiii 
of  the  air-valve  spring,  the  arrangement  of  the  lK^t-«iir  passage  lendiixg 
(o  it.  or.  if  these  prove  insufficient,  the  changing  of  the  priinarA' 
nozzle.    The  last  change  is  opposetl  by  the  makers. 

Beyond  this,  the  only  adjustment  piissible  li^-s  >n  the  ht>t-ttir 
dtoike  \alve  whwA  can  be  moveil  or  iiltetwl  fnun  tlie  dash  to  give 
more  or  less  bot  air.  The  partial  closing  of  t\m  valve  makes  staniiig 
easier  and  helps  tbe  running  of  the  motor  until  it  gets  warauxl  up. 
but  in  nonnal  nmoiiig  iu  manipulation  has  little  etftvt.  In  gating 
farther  than  this,  tbe  only  possibility  lies  in  altering  tlie  design  by 
^-aning  tbe  omnection  between  the  two  throttles,  so  the  se*.vnd  static 


r^ 


GASOLINE  AUTOMOBILES 

cuts  in  sooner  or  later,  but  this  might  impair  the  usefulness  of  the 
instrument.  The  same  is  true  if  the  secondary  nozzle  is  changed. 
The  device,  then,  is  really  lacking  in  adjustments  in  the  ordinary 
sense,  except  for  the  initial  setting  of  the  primary-stage  air  valve. 

Newcomb  Carburetor.  The  Newcomb  carburetor  is  made  by  the 
Holtzer-Cabot  Electric  Company  and  is  a  constant  vacuum  tjpe 
having  a  single  nozzle  and  an  eccentric  float  chamber.  It  is  a  high- 
grade  instrument  and  is  used  only  on  the  highest-priced  cars.     As 


GASOLINE  AUTOMOBILES  155 

which*  is  of  normal,  or  usual,  construction,  except  for  the  regulating 
cap  77  on  the  top  of  the  central  opening  above  the  float  needle  85. 

Around  the  bottom  edge  of  the  plunger  69  a  large  number  of 
holes  of  small  size  are  drilled,  and  these  are  arranged  to  register  with 
an  equal  number  of  relatively  narrow  air  slots  cut  in  the  bottom  of  the 
plunger  chamber  walls.  These  distribute  the  fuel  after  it  has  passed 
up  the  central  well,  issued  from  the  nozzle,  and  been  drawn  within 
the  plunger.  The  plunger  when  at  rest  is  seated  on  the  collar  70y 
which  is  threaded  into  the  bottom  of  the  plunger  chamber  and  is  used 
as  a  means  of  adjustment,  as  will  be  explained  later.  This  collar  is  so 
set  as  to  raise  the  plunger  slightly,  thus  opening  the  fuel  nozzle  without 
uncovering  the  air  slots  in  the  plunger  chamber.  In  this  way,  the  fuel 
port  is  given  a  lead  with  respect  to  the  air  ports,  so  that  a  rich  mixture 
is  delivered  when  the  plunger  is  raised  a  little,  as  in  starting  or  idling. 

When  air  is  drawn  through  the  carburetor  by  the  motor  suction, 
the  plunger  lifts  in  proportion  to  the  amount  of  air  entering.  This 
lifts  the  needle  and,  at  the  same  time,  releases  the  exact  amount  of 
fuel  needed  to  charge  the  ehtering  air  correctly  and  thoroughly.  The 
higher  the  plunger  is  lifted,  the  greater  the  air  and  fuel  openings. 
The  effective  areas  of  these  air  and  fuel  ports  are  so  proportioned  as 
to  be  correct  at  all  positions.  The  slots  in  the  plunger  chamber  walls 
being  small,  the  jets  of  air  coming  through  them  have  a  high  velocity, 
S3  that  the  fuel  is  atomized  as  it  issues  at  these  points.  Any  unatom- 
ized  or  unvaporized  fuel  is  thrown  against  the  heated  walls  of  the 
vaporizing  chamber,  which  are  made  greatest  in  area  in  this  region. 
This  produces  a  dry  gas  and  high  fuel  economy.  The  gas  passes 
around  the  outside  of  the  plunger  chamber,  through  the  main  throttle 
valve,  and  thence  goes  into  the  inlet  manifold. 

Starting  Device.  The  small  pipe  shown  at  101  is  a  starting  device 
and  consists  of  a  pipe  connection  from  the  lower  part  of  the  float 
chamber  into  the  gas  outlet  passage  above  the  throttle  valve.  When 
about  to  start,  the  throttle  is  thrown  over  to  a  position  in  which  the 
opening  of  this  pipe  is  included  in  the  manifold  above  it.  It  is  then 
susceptible  to  the  partial  vacuum  existing  there,  and  pure  fuel  in  a 
very  fine  spray  is  drawn  directly  into  the  manifold.  Under  normal 
running  conditions,  its  operation  is  negligible. 

The  Dashpot.  This  device  has  a  solid  head  to  the  plunger  69 
and  also  to  the  plunger  chamber  68  in  which  it  works.    Between  the 


156 


GASOLINE  AUTOMOBILES 


two  there  is  a  considerable  space,  and,  as  the  plunger  is  a  fairly  close 
fit  in  the  chamber,  this  acts  as  a  dashpot  and  retards  the  speed  of  tlie 
plunger  when  the  motor  is  accelerating,  or  when  tlie  throttle  is  opened 
suddenly.  By  retarding  the  speed  of  the  plunger,  a  richer  mixture 
is  obtained  at  the  precise  time  when  it  is  needed,  in  fact,  demanded, 
by  the  motor.  And  yet  when  the  plunger  rises  and  stops  rising,  the 
mixture  again  becomes  normal.  This  arrangement,  therefore,  does 
not  need  an  extra  rich  setting  in  order  to  obtain  good  acceleration, 
for  the  engine  can  run  on  a  lean  mixture  with  a  rapid  pick-up. 

Mixture  IndiccUing  Pointer.  The  toji  of  the  float  chamber  carries 
a  name  plate  8S  on  which  a  graduated  arc  varying  from  t  to  5  is 
etched ;  the  1  end  being  marked 
Ijoor,  and  the  9  end  rich,  as  sliown 
in  Fig.  109.  On  the  top  center 
ofthefloatchamber  is  a  regulating 
cap  77.  Fig.  108;  attached  to  the 
top  of  it  is  the  regulating  pointer 
7tS',  which  traverses  the  arc  shown 
and  in  this  way  indicates  the 
quality  of  the  mixture  being 
formed  with  that  setting.  Thi.'* 
pointer,  shown  as  straight,  but 
ha^-ing  two  bends,  from  a  hori- 
zontal to  a  vertical  and  back  to  a 
horizontal  at  the  scale,  ha^  a  small 


GASOUNE  AUTOMOBILES  157 

AdjuttmeniJt.  There  are  but  two  adjustments:  the  load- 
carrying  adjustment  controlled  by  the  pointer  7S  and  cap  77  just 
described;  and  the  idhng  adjustment  controlled  by  the  regulating 
collar  70,  mentioned  previously,  and  shown  in  Fig.  108.  Contrary  to 
the  usual  method,  the  load-carrjing  adjustment  is  made  first,  and  the 
low-speed,  or  idling,  adjustment  is  made  last.  To  make  the  load- 
cuiying  adjustment,  set  the  throttle  in  the  special  starting  position 
as  descrihed,  turn  the  regulating  pointer  to  the  rich  position  on  the 
dial,  then  screw  the  slow-speed  ring,  or  regulating  collar,  70  as  fa-r  up 
it  will  go.  This  is  the  rich  position  of  the  ring  for  starting  only. 
Flood  the  carburetor  by  means  of  the  tickler  94  until  gasoline  appears 
.on  top  of  the  float  chamber.  Then  start  the  motor  and  immediately 
move  the  throttle  to  a  running  position,  othenvise  the  motor  will  stall. 
With  the  motor  running  nomially,  move  the  regulating  pointer 
78  to  about  5  on  the  dial;  this  gives  an  average  setting,  but  different 
points  should  be  tried  and  the  poor-mixture,  or  lean-mixture,  side 
^uld  be  favored  alwajs.  To  obtain  the  t>est  setting,  move  the 
pomter  half  a  point  at  a  time,  and  try  out  the  setting  each  time  on 
the  road.  When  the  best  setting  has  been  found  for  some  one  condi- 
tion of  motor  speed  and  load,  the  mixture  will  be  found  correct  under 
all  conditions  except  idling. 

Idling  and  Low-Speed  Adjustment.  Now  that  the  load-carry- 
ing adjustment  has  been  made,  the  ring  70  which  adjusts  the  mixture 
for  idling  should  be  unscrewed  to  weaken  the  mixture  until  the  motor 
throttles  evenly,  without  loading  or  popping  when  accelerated. 
Possibly  the  best  combination  of  slow  running  and  quick  smooth 
accelenttion  may  call  for  a  slightly  richer  mixture  than  that  on  which 
the  motor  idles  best  and  slowest.  After  this  setting  has  been  made, 
to  see  if  the  ring  is  screwed  up  too  far  and  is  giving  a  richer  mixture 
than  is  necessary,  move  the  regulating  pointer  78  slowly  from  the 
No.  5  point  toward  poor.  If  the  motor  speeds  up,  the  mixture  is 
too  rich,  and  the  ring  70  should  be  unscrewed  until  the  motor  idles 
correctly  with  the  pointer  in  the  position  found  to  be  correct  for  the 
load-carrying  mixture.  After  the  correct  idling  position  has  been 
found,  all  variadons  for  atmosphere,  temperature,  and  fuel  conditions 
should  be  made  by  changing  the  pointer  only. 

Marvel    CarburebM'.    The    Marvel    carburetor.    Model    "E", 
shown  in  section  in  Fig.  110,  is  notable  for  using  the  exhaust  g&se& 


lyiiiiancai  float  C  ha 


GASOLINE  AUTOMOBILES  159 

These  exhaust  gases  pass  downward  through  an  external  cylin- 
drical passage  and,  after  warming  the  Venturi  and  primary  nozzle 
r^on,  escape  to  the  atmosphere.  This  gas  is  obtained  by  tapping 
into  the  exhaust  manifold  within  a  few  inches  of  the  last  cylinder  out- 
let (4  inches  are  recommended).  As  the  motor  demand  rises  beyond 
the  ability  of  the  primary  nozzle,  the  inclined  air  valve  is  drawn 
toward  the  vertical  position.and,  as  soon  as  it  leaves  the  cylinder  wall, 
the  high-speed  nozzle  is  uncovered  and  starts  to  contribute.  The  air. 
is  supplied  from  the  same  air  inlet,  but  it  rises  more  directly.  A 
throttle  is  placed  in  the  air  inlet  to  facilitate  starting;  closing  this 
cuts  off  the  air,  so  that  a  richer  mixture  is  supplied.  There  is  a 
damper,  or  throttle,  F  in  the  exhaust  gas-inlet  passage.  It  is  inter- 
connected with  the  main  throttle  G  in  such  a  way  that  it  is  opened 
when  the  latter  is  closed  and  closed  when  the  latter  is  opened.  The 
idea  is  to  furnish  a  great  quantity  of  heat  when  the  throttle  is  nearly 
closed,  and  to  gradually  diminish  the  supply  as  the  throttle  is 
opened  and  the  motor  warms  up. 

Adjuatmenta.  There  are  two  adjustments:  the  gasoline  adjust- 
ment //,  so-called  by  the  maker,  and  the  air  adjustment  /.  The  gaso- 
line adjustment  operates  the  primary  nozzle.  These  preliminary 
adjustments  can  be  made  on  the  instrument  as  received  by  closing 
the  gasoline  needle  valve  //  by  turning  it  gently  to  the  right  until 
seated,  then  opening  it  by  turning  to  the  left  ^  turn.  The  air- 
adjusting  screw  /  should  be  turned  until  the  end  of  the  screw  is  about 
even  with  the  edge  of  the  spring  ratchet  J  provided  to  hold  it  when 
set.  After  starting,  close  the  throttle  to  produce  a  moderate  speed. 
Then  close  the  gasoline  needle  //a  very  little  at  a  time  until  the  motor 
runs  smoothly.  Allow  the  motor  to  get  thoroughly  warmed  up, 
though,  before  making  the  final  adjustment. 

Next,  adjust  the  air  valve.  Turn  the  adjusting  screw  /  to  the  left 
to  back  it  out  and  release  the  air  spring  about  one-eighth  of  a  turn  at 
a  time  until  the  motor  begins  to- slow  down.  This  indicates  that  the 
screw  is  too  loose,  so  turn  back  slowly,  one-eighth  of  a  turn  at  a  time, 
until  it  runs  smoothly  again.  Next,  advance  the  spark  two-thirds  of 
its  travel  and  open  the  throttle  quickly.  The  motor  should  speed  up 
promptly  and  quickly.  If  it  hesitates  or  pops  back  a  little  more 
gasoline  should  be  released  at  the  needle  valve  H  by  turning  it  to 
the  left  a  very  little  at  a  time.    It  may  also  be  necessary  to  t\^\jea 


160  GASOLINE  AUTOMOBILES 

the  air  screw  /  a  little  more.  Now,  wait  for  the  motor  to  settle  down 
to  this  new  adjustment,  then  open  the  throttle  again  quickly.  Con- 
tinue this  sudden  throttle  opening  and  subsequent  adjustment  until 
the  point  is  readied  where  the  motor  will  respond  in  a  satisfactory 
manner  to  a  sudden  throttle  opening.  The  highest  economy  is 
obtained  hy  turning  the  air  screw  to  the  left  and  the  gasoline  needle  H 
to  the  right,  dosing  it  as  nearly  as  possible  and  still  obtain  the  desired 
results. 

Fuel  Supply.  When  the  carburetor  is  fed  by  gravity,  the  bottom 
of  the  bowl  should  be  at  least  eight  inches  below  the  bottom  of  the 
gasoline  tank.  When  it  is  fed  by  pressure,  one  pound  is  sufficient, 
and  two  poimds  should  never  be  exceeded. 

The  Marvel  Carburetor  Company  also  makes  a  Model  "N". 
designed  for  Ford  cars  to  which  it  can  be  attached  without  diange  of 
manifold,  levers,  or  otlier  fittings.  It  is  built  on  tlie  same  general 
plan  as  the  Model  "E"  previously  illustrated  and  described. 

Schebler  Carburetors.  The  Schebler  carburetor  is  one  of  the 
simplest  complete  carburetors  made.  In  general,  all  Scheblers  have 
a  concentric  float;  a  single  needle  valve,  the  position  of  which  can 
be  adjusted  to  suit  varying  needs;  and  an  auxiliary  air  valve  which  is 


GASOUNE  AUTOMOBILES 


161 


carburetor  by  means  of  tlie  priming  lever  C,  hglding  this  up  about 
five  seconds.  Open  the  throttle  one-third  and  start  the  motor,  then 
dose  the  throttle  slightly  and  retard  the  spark.  Next,  adjust  the 
throttle-lever  screw  F  and  needle-valve  adjusting  screw  B  until  the 
motor  runs  at  the  desired  speed,  smoothly  and  evenly  on  all  cylinders. 
Then  make  the  high-speed  adjustment  on  the  dials  D  and  E.  Turn 
the  pointer  on  the  dial  D  from  1  toward  3,  about  half  way.  Advance 
the  spark  and  open  the  throttle  so  the  roller  on  the  track  running 
below  .the  dials  is  in  line  with  the  first  dial.  If  the  motor  back-fires, 
turn  the  indicator  a  little  more  toward  3,  or,  if  the  mixture  is  too  rich, 
turn  the  indicator  back  toward  /  until  it  runs  properly.    Now  open 


the  throttle  wide  and  make  the  adjustment  on  dial  E  for  the  high 
speed  in  the  manner  just  completed  on  D  for  intermediate.  As  lean 
a  mixture  as  the  motor  will  stand  is  advised. 

This  model  is  also>made  with  a  dash-control  air  valve,  as  shown 
separately  at  the  left  of  Fig.  111.  Otherwise  the  carbui^tor  and 
adjustment  are  exactly  the  same,  except  that  where  the  directions 
previously  given  above  have  read  A,  those  dealing  with  the  dashboard 
connection  should  read  Ai.  As  will  be  noted,  the  movement  of  this 
lever  rotates  a  small  gear  which  engages  with  a  rack  formed  in  the  air- 
valve  stem,  so  that  movement  of  the  lever  gives  the  same  result  as 
turning  the  screw  A, 


zfpLmat  the  «top  C  when  the  lever  oc 
reiriitter*  lean,  or  air.     ThL-  L^  the  Drcier 


ConrUtif  ef  WhetUr  and  HrhebUr,  Indianapclu,  Iwiiama 

Unimm  on  the  air-valve  spring.    Turning  t 

or  ckxrkwise,  lifts  the  needle  v»lv#»  ^  — -^ 
.1 


GJ^SOUXE  AUTOMOBILE 


163 


present-day  fueb and  thr motor conditknsbettrr.  AsF%.  llSdiows, 
the  Yentari  tube  b  made  much  loofTr  by  an  upward  ejrttosion,  whUt 
the  needle  has  been  changed  so  that  it  mox'vs  downward  to  open;  abo 
the  needle-^-ahre  adjustment  has  been  remoxTd  frooi  the  air  \'al\Y 
and  placed  on  the  otha  side.  In  addition,  the  neetlle  v-ahT,  or  meter- 
ing (mu,  is  sutnoerged,  that  is.  the  pwnt  b  atw«\-$  below  the  fuel  )e\'el: 
and  a  starting  de\-ice,  seen  in  the  tonn  of  a  dash  rontrtd,  pushes  the 
metering  pLn  down  and  holds  the  auxiliar>'  air  \'alve  dosed^in  order 
to  produce  a  vef>-  lii^  mixture  for  starting.  As  to  adjustments,  the 
air-valve  and  dash  amngetnents  are  abi>iit  the  same  as  on  the  "R". 
but  the  new  fuel  adjustment,  by  means  of  the  milled  Headed  screw  G. 


seen  in  the  right-hand,  or  end,  view,  is  managed  in  much  the  same  way 
as  the  needle-valve  adjustment  on  Model  "L". 

Adjustment  of  Model  "  T"— Horizontal.  The  new  Model  "T", 
Fig.  114,  has  a  horizontal  outlet  and  is  intended  to  be  fastened 
directly  to  the.cylinders,  doing  away  with  the  inlet  manifold  entirely. 
This  necessitates  more  vaporizing  space  and  changes  the  external 
appearance  considerably.  Float,  fuel  supply,  and  throttle  are  all  the 
same;  the  metering  pin  is  controlled  by  the  operation  of  the  air  valve, 
as  in  the  previous  models,  and  the  primary  air  opening  is  fixed  but 
ia  by-passed  through  the  Venturi  to  the  high-speed  air  opening. 
Tlie  high-speed  air  valve  opens  over  the  Venturi,  and  the  ui  v%  dtvvrc^ 


Fij?.   114.     Schebler  Carburetor.  Model  *'T".  with 
Horizontal  Outlet 


at 

inj 

bii 

is 

far 

sen 

sen 

the 

moi 

dial 

trol, 

oper 

turn 

or 

wan 

turn 

the 

very 


begins  to  miss  fire,  then  turn  toward  i 
until  it  is  firing  evenly.  Make  this  last  ad; 
set  to  idlp  «+ ^^^'^ '^'^''•~   ' 


GASOUNE  AUTOMOBILES 


165 


moving  part,  is  drawn  upward  by  the  suction  of  the  motor  and  comes 
back  down  onto  its  seat  through  its  own  weight  when  the  suction  is 
lessened.  Id  Fig.  115,  the  complete  cart>uretor  with  the  throttle 
open  is  shown  at  the  right,  and  the  vaporizing  chamber  only  and  with 
throttle  closed  is  shown  at  the  left;  the  float  chamber  is  the  same  in 
both  cases.  Gasoline  flows  in  through  the  strainer  to  the  float 
chamber,  thence  to  the  dashpot,  filling  this  and  continuing  to  rise  to 
a  point  about  on  a  line  with  the  top  of  the  tapered  metering  pin, 
which  corresponds  to  the  usual  needle  valve. 

With  the  engine  at  Test,  as  shown  by  the  left-hand  figure,  the 
upper  end  of  the  metering  valve,  which  has  a  conical  lower  surface. 


rests  upon  the  valve  seat,  thus  closing  the  main  air  passage.  Its 
lower  end  extends  down  into  the  gasoline  in  the  dashpot.  Through  its 
center  is  an  opening,  known  as  the  aspirating  tube,  into  the  low^r  end 
of  which  extends  (from  below)  the  tapered  metering  pin.  As  soon  as 
the  motor  starts,  or  is  turned  over,  so  that  a  partial  vacuum  is  created 
in  the  mixing  chamber,  the  metering  valve  is  lifted  to  admit  airpast  the 
valve  seat,  asshown  in  the  right-hand  part  of  the  figure.  This  vacuum 
is  also  communicated  to  the  fuel  chamber  through  the  aspirating 
tube,  drawing  gasoline  through  it  and  up  the  central  passage ;  the  latter 
is  expanded  in  diameter  near  the  top  and  is  then  flared  out  to  a  large 
coze  at  the  point  where  the  air  entering  through  the  vertical  holes  in 
the  metering  valve  meets  the  gasoline  and  picks  it  up.    T1[i&'^MXV<3«& 


._ .,  una  nil  DV  ITIcailSiif  il  ) 

to  the  inetcriiift  pin  in  >ucli  u  wiiy  tliaf ,  v 


GASOLINE  AUTOMOBILES  167 

increasing  or  decreasing  the  relative  amount  of  gasoline  admitted  to 
the  mixing  chamber  in  response  to  the  movement  of  the  metering 
valve.  This  movement  is  produced  by  the  rotation  of  the  small  gear 
A,  which  engages  with  a  rack  on  the  lower  end  of  the  tapered  metering 
pin.  This  gear  is  rotated  by  means  of  a  flexible-wire  (Bowden)  con- 
nection to  the  dash  control.  The  limit  of  this  motion,  as  well  as  the 
normal  position  of  the  gear,  is  governed  by  the  setting  of  the  adjusting, 
or  stop,  screw  B,  shown  in  the  external  view.  Fig.  116. 

This  screw  can  be  turned  either  way;  turning  it  to  the  right 
lowers  the  position  of  the  metering  pin,  admitting  more  gasoline; 
and  turning  it  to  the  left  raises  it  so  that  less  fuel  is  admitted.  A 
wider  range  of  adjustment  than  this  stop  screw  affords  can  be  had  by 
releasing  the  clamp  C  of  the  pinion-shaft  lever  D  and  moving  it  around 
to  a  new  position  on  the  shaft.  This-  adjustment,  however,  is  not 
recommended  except  for  expert  repair  men. 

With  the  motor  idling  the  adjustment  should  be  made  by  moving 
the  screw  up  and  down,  that  is,  out  and  in  until  the  motor  runs 
smoothly.  This  adjustment  must  be  made  with  the  dash  control 
pushed  all  the  way  in.  When  this  simple  adjustment  is  made  cor- 
rectly, the  device  is  practically  automatic  from  that  time  on.  A  stop 
screw  E  on  the  throttle  lever  is  movable  and  affords  the  equivalent 
of  a  limited  adjustment,  for  it  can  be  set  to  give  a  smaller  and  smaller 
opening  and  thus  slower  and  slower  idling.  It  also  has  an  influence 
on  the  maximum  opening  which  influences  the  highest  speed. 

Johnson   Carburetor.    The  Johnson   carburetor,   of  which   a 
section  through  Model  "D"  is  shown  in  Fig.  117,  is  one  of  the  newer 
designs  to  be  placed  on  the  market.    It  is  a  simple  form,  with  a  con- 
centric type  of  float  chamber  A,  above  which  is  a  simple  cylindrical 
mixing  chamber  B  containing  the  air-regulating  device.    It  is  sur- 
rounded by  a  hot-air  jacket  C,  which  warms  the  mixing  chamber  and 
furnishes  the  primary  air  supply.  •  This  is  composed  of  the  strangle 
tube  D  and  air  controlling  sleeve  E,  with  a  lift  plate  F  suspended 
from  this  sleeve  in  the  strangle  tube. 

Operation,  Gasoline  enters  the  float  chamber  from  above,  in 
the  usual  way.  It  enters  the  spray  nozzle  through  the  cross-hole  G, 
then  rises  inside  this  and  passes  the  tip  of  the  needle  H,  where  it  con- 
tinues out  through  the  nozzle  point  into  the  lower  part  of  the  mixing 
chamber.    The  fuel  issues  as  a  fine  spray  into  the  strangle  tube  D  y 


GASOLINE  AUTOMOBILES 


which  is  conical  in  shape.  In  the  mbdng  chamber  is  a  sliding  brass 
sleeve  E,  which  moves  up  and  down  according  to  the  engine  suction 
and  carries  the  lift  plate  F  which  is  just  above  the  outlet  from  the 
spraying  nozzle.  Warm  air  enters  the  air  inlet  /  and  finds  it3  way 
around  the  chamber  C,  some 
of  it  reaching  the  passage  J 
below  the  lift  plate  and  stran- 
gle tube.  Here  it  picks  up  the 
fuel  from  the  nozzle  and  im- 
pinges it  against  the  lift  plate 
to  break  it  up  into  finer  parti- 
cles. In  addition,  the  rising 
air  and  fuel  raise  the  plate  and 
with  it  the  sleeve  E,  allowing 
more  air  to  enter  around  the 
bottom  of  the  sleeve.  By  this 
arrangement,  the  current  of  air 
is  divided  and  forms  both  the 
primary  and  the  auxiliary  cur- 
rents. The  latter  current  is 
varied  to  suit  the  engine  de- 
mands by  the  rising  and  falling 
of  the  sleeve.  This  move- 
ment of  the  sleeve  automat- 
icall\'  proportions  the  air  and 
gas  to  the  demand,  for,  in 
rising,  the  lift  plate  is  drawn 
away  from  the  nozzle  tip,  and 
morefuelisallowed  toflowout. 
On  top  of  the  strangle 
tube  rests  a  flat  choker  plate 
A',  which  is  capable  of  being 
turned  around.  There  are 
holes  in  this  to  correspond  with  the  holes  in  the  strangle  tube  through 
which  the  primary  air  passes  down  to  the  lower  side.  In  rising  again, 
it  picks  up  the  fuel  spray.  A  lever  L  extends  through  the  outside  of 
the  carburetor  and  is  connected  up  to  the  dash  control.  This  lever 
controls  the  choker  plate  which  can  be  moved  around  to  cover  or 


GASOLINE  AUTOMOBILES  I6d 

uncover  the  air  holes  and  give  more  or  less  primary  air  as  the  device 
needs  it.  Thus,  the  low-speed  screw  M,  the  needle  valve,  and  the 
stop  screw  N  on  the  throttle  shaft  constitute  the  adjustments. 

Adjusting  the  Johnson,  The  function  of  the  low-speed  screw  is 
to  admit  or  to  cut  off  the  small  amount  of  air  supply  to  the  upper 
part  of  the  mixing  chamber  as  the  motor  demands;  this  screw  is  to  be 
adjusted  only  with  a  closed  throttle,  retarded  spark,  and  the  motor 
idling.  The  motor  should  be  hot.  This  is  ^n  idling  adjustment, 
designed  to  supply  additional  air  through  the  opening  0,  the  need  for 
which  is  caused  by  the  sleeve  E  being  in  its  bottom  position  and  thus 
cutting  off  the  supply,  which  is  available  later  when  the  sleeve  has 
risen  and  in  so  doing  has  formed  the  annular  air  passage. 

The  spray  needle  //,  adjusted  by  the  external  handle,  takes  care 
of  all  other  throttle  positions  and  speeds  by  admitting -more  or  less 
fuel.  To  adjust  it,  turn  the  low-speed  screw  and  spray  needle  to 
their  seats  and  set  the  throttle-lever  stop  screw  to  approximate  the 
correct  closed  position.  Open  the  spray  needle  one  and  one-half 
turns.  Start  the  motor,  and  when  it  has  warmed  up,  place  the  spark 
lever  in  the  fully  retarded  position;  then  open  the  throttle  quickly, 
and  if  the  motor  does  not  back-fire,  the  mixture  is  slightly  rich  and 
the  spray  needle  should  be  closed  by  turning  to  the  right  about  one- 
eighth  of  a  turn.  Again  open  the  throttle  quickly  and  repeat  until  the 
motor  does  back-fire;  this  will  determine  a  lean  mixture.  Open  the 
needle  slightly  to  correct  the  mixture,  which  will  give  the  correct 
adjustment  on  high  and  intermediate  speed.  Adjust  the  throttle 
stop  screw  until  the  desired  idling  speed,  or  about  240  r.p.m.,  is  secured. 
If  the  motor  does  not  fire  continuously  and  run  smoothly,  the  low- 
speed  mixture  is  too  rich  and  is  corrected  by  backing  out  the  low-speed 
screw  M  until  sufficient  air  is  admitted  for  smooth  even  firing.  Then 
lock  it  with  the  lock  nut.  If  this  last  adjustment  has  increased  the 
speed  of  the  motor,  restore  the  idling  speed  by  unscrewing  the  throttle 
stop  screw  N  slightly.  If  necessary,  reset  the  low-speed  screw,  as 
both  of  these  have  to  be  adjusted  in  combination. 

Dash  Control,  This  controls  the  choker  plate,  which  acts  as  a 
choke  to  the  nozzle  by  reducing  the  supply  of  primary  air.  After 
the  motor  has  been  warmed  up,  this  should  be  in  the  wide-open 
position.  The  position  for  a  cold  motor,  approximating  the  closed 
position,  will  be  determined  by  experience.     It  is  recommeud^  \.Vk^\. 


1*6 


GASOLINE  AUTOMOBILES 


the  motor  be  choked,  that  is,  the  dash  control  set  in  the  closed  position, 
when  stopping.  This  provides  a  rich  charge  for  starting.  As  will 
lie  seen  from  this,  the  choker  plate,  with  its  dash  control,  is  primarily 
a  starthig  device. 

Other  Models.  This  carburetor  is  made  in  other  models,  notably 
a  small  one  for  the  Ford  car;  the  essential  difference  in  this  being  the 
location  of  the  low-speed  screw  on  top,  as  it  has  a  horizontal  outlet 
on  one  side  and  the  warm  air  inlet  on  the  other.  Another  large  size 
for  eight-r\linder  models  has  a  special  accelerating  device  consisting 
of  a  fuel  plunger  operated  from  the  throttle.  Still  another  model  is  a 
fixed-needle  type  in  which 
the  nozzle  is  calibrated  for 
the  motor.  The  adjust- 
ment is  practically  the 
same  for  all  these. 

Carter    Carburetor. 

The  Carter  carburetor  is 

a   multiple-jet    device   in 

which,  at  slow  or   idling 

'  i^peed.  but  one  jet  is  fur- 


GASOLINE  AUTOMOBILES  171 

and  rises  vertically  along  it.  Around  the  upper  part  of  the  standpipe 
is  a  flaring  conical  tube,  the  top  of  which  is  closed  by  a  damper.  Air 
enters  here  and  is  drawn  downward,  its  amount  being  controlled  by  the 
damper.  At  the  left  will  be  seen  the  supplementary  air  valve,  a  third 
source  of  air;  this  air  is  also  drawn  downward,  and  the  amount  is 
adjustable.  From  this  it  can  be  seen  that  the  primary  air  and  the  fuel 
from  the  first  few  jets  come  upward,  while  the  secondary  air  and  the  fuel 
bom  the  additional  jets  go  downward,  and  that  the  supplementary  air 
rushes  in  at  an  angle  where  these  two  meet  at  the  bottom  of  the 
U-shaped  vaporizing  chamber.  This  produces  a  constant  state  of 
turbulence  around  the  standpipe,  which  facilitates  breaking  up  and 
vaporizing  the  fuel.  The  fuel  passes  a  butterfly  throttle  in  its 
passage  to  the  inlet  manifold. 

For  easy  starting,  a  tube  (marked  anti-strangling  tube  in  the  cut) 
is  by-passed  around  the  vaporizing  chamber,  taking  its  fuel  directly 
from  the  well  at  the  left  of  the  float  chamber  and  furnishing  it 
directly  into  the  outlet  pipe  above  the  throttle.  In  starting  and 
idling  on  the  lowest  jet,  or  hole,  of  the  stdndpipe,  the  fuel  is  drawn 
almost  directly  from  the  float  chamber.  For  this  reason  an  unusually 
accurate  float  arrangement  is  necessary,  and  this  is  provided  by  the 
metal  ball  float  and  the  needle  arrangement  with  its  ball  and  spring 
shock  absorber.  The  latter  eliminates  any  possibility  of  jamming 
and  gives  accurate  control  of  the  fuel  level.  The  action  of  the  device 
is  very  simple,  the  engine  suction  drawing  the  fuel  higher  and  higher 
in  the  standpipe  as  the  suction  increases,  while  the  same  suction  draws 
t^ten  the  intermediate  air  valve  as  soon  as  the  required  supply  exceeds 
the  capacity  of  the  main  air  intake.  The  high-speed  air  inlet,  oper- 
ated by  the  damper,  is  thrown  into  action  from  the  steering  post  or 
dash  at  the  will  of  the  operator. 

Adjuring  the  Carter.  By  reference  to  Fig.  118,  and  also  to 
Fig.  1 19,  which  shows  the  exterior  of  the  device,  the  method  of  adjust- 
ing will  be  made  plain.  First  set  the  high-speed  adjustment  with  the 
lever  in  a  vertical  position;  then  turn  the  knurled  button  marked  low- 
speeA  adjustment  down,  or  to  the  right,  as  far  as  it  will  go;  neict  back 
it  off  and  turn  it  to  the  left  three-quarters  of  a  turn.  Turn  the 
knurled  valve  ring. marked  intermediate-speed  adjustment  to  the 
point  where  the  valve  seats  lightly,  then  turn  the  valve  down,  or 
to  the  ri^t,  from  eight  to  ten  notches  to  increase  the  spnng  temvoTv. 


m 

_ 

172                        GASOLINE  AUTOMOBILES 

Puil  the  easy-starting  lever,  connected  with  the  dash,  forward  to  the 
jmsition  shown  in  Fig.  119,  advance  the  spark  a  very  little,  close 
the  throttle,  and  start  the  engine. 

Through   the   medium  of   the   anti-strangling  tube,   thia  will 
furnish  rich  mixture  (almost  pure  fuel)  to  tlie  inlet  manifold  and 
result   in  instantaneous  starting.     Immediately   reverse   the   easy-    ■ 
starting  lever  which  controls  the  flow  of  fuel  and  open  the  main 
throttle  slightly.     By  means  of  the  two  screws  A  A  on  either  side 
of  the  throttle  lever,  set  the  throttle  valve  where  it  gives  the  desired 
engine  speed  when  idling. 
^^tOj^m^m   W^^                ^^"''^  ^^^   low-speed  ad- 

k- 

^^^^L      notch  at  a  time,  until  the 
^^^^^K    engine  slows  down,  noting 
^^^^H    each  setting.     Now  move 
^^^^^       it  in  the  opposite  direc- 
^H             tion.  one  notch  at  a  time, 
.                       until    the    engine    again 
a^                 slows  down.     Then  move 
O                 the  adjustment  to  a  point 

i 

k^ 

GASOLINE  AUTOMOBILES 


173 


temperatures,  or  when  the  engine  is  cold,  this  control  should  be  moved 
toward  the  closed  position,  so  as  to  cut  off  air  and  make  a  richer  mix- 
ture. At  high  temperatures  and  with  a  warm  engine,  the  best  results 
are  obtained  with  the  control  wide  open.  This  is  the  only  adjust- 
ment which  should  be  varied  for  weather  or  temperature  variations. 
Packard  Carburetor.  The  carburetor  used  on  the  Packard 
twin-six  (twelve-cylinder)  cars  is  shown  in  section  in  Fig.  120.  The 
inlet  manifold,  or  rather  the  pipe  which  leads  in  both  directions  to  the 


manifold  proper,  is  seen  at  the  top  at  A.  It  will  be  noted  that  this  is 
water-jacketed,  the  water  space  being  at  the  top.  The  float  arrange- 
ment is  of  the  usual  type,  with  a  metal  float  which  supplies  fuel  to  a 
small  well  B  at  the  base  of  the  single-sp^a^'  tube  C.  This  has  a  flared 
end  located  in  the  center  of  the  Venturi.  When  the  air  from  the  air 
bom  D  passes  the  air  shutter  E,  it  picks  up  the  fuel  and  carries  it  up 
into  the  vaporizing  chamber  F.  The  primary  air  shutter  is  normally 
open  but  not  in  use.  It  is  operated  by  a  hand  wheel  on  the  control 
board  which  also  operates  the  auxiliary  air  valve  G.    By  tmnvu^  t.\v\& 


174  GASOLINE  AUTOMOBILES 

dear  over  to  the  position  marked  choke,  the  air  intake  is  closed,  and  a 
rich  mixture  is  drawn  in  tor  starting.  After  that,  the  hand  wheel 
should  be  set  back  toward  the  position  marked  air  which  opens  the 

The  auxiliary  air  valve  is  controlled  by  the  springs  H  and  I. 
These  are  adjusted  so  that  the  valve  opens  very  slightly  at  low  speed, 
but  more  and  more  as  the  speed,  and  consequently  the  suction, 
increases.  The  air  enters  around  the  outside  of  the  ^'enturi,  communi- 
cating with  the  mixture  only  above  the  top  of  the  latter  where  the 
real  vaporizing  chamber  commences.  The  tension  of  the  springs  is 
\-aried  by  means  of  the  adjusting  nuts  at  the  top  and  by  the  adjusting 
CB-tnaJ,  The  cams  are  connected  up  to  the  air-valve  hand  wheel  which 
is  turned  toward  jias  to  provide  a  richer  mixture  and  toward  air  for  a 
leaner  mixture.  If  the  wheel  is  turned  too  far  toward  air,  spitting 
back  may  result;  and  if  it  is  turned  too  far  toward  gas,  the  result  may 
bo  irregular  running  and  overheating.  The  throttle  K  is  of  the  but- 
terfly tvpe  and  regulates  the  quantity  of  mixture  allowed  to  pass  out, 
not  its  quahty.  An  adjustable  stop  holds  this  valve  open  slightly 
and  allows  a  small  amount  of  mixture  to  pass,  even  when  the  hand 
throttle  is  entirely  closed.  This  minimum  amount  is  for  slowest 
running,  or  itilinif,  only.     To  increase  it,  loosen  the  check  nut  /..  and 


GASOUNE  AUTOMOBILES 


175 


ir.  This  air  reaches  the  passage  L,  whence  a  portion  is 
iward  around  the  outside  of  the  Veoturi  /,  through  the 
ind  around  the  hottom  of  the  tube,  then  upward.  There 
h  the  fuel  spray,  vaporizes  it,  and  carries  it  up  into  the 
zing  chamber  N,  where  additional  air  comes  in  from  L, 


.ture  passes  on  up,  through  the  throttle  valve  0,  into  the 
Id. 

tver  P  attached  to  the  throttle  valve  shaft  is  hung  the 
■od  Q,  by  means  of  which  it  is  attached  at  its  lower  end  to 
^  This  works  up  and  down  in  the  cliamber  8.  Its  lower 
rell,  T  is  full  of  fuel  and  communicates  through  passage  V 
tl  F  and  the  nozzle  H.  When  the  throttle  is  opened,  the 
orced  into  the  gasoline  in  the  carburetor  bowl,  and  fuel 
ed  through  the  hole  (?  up  to  the  nozzle  H.    VHum  ii)Qft 


17d 


GASOLINE  AUTOMOBILES 


throttle  ia  opened  quickly,  this  acts  to  supply  the  needed  fuel.  When 
the  throttle  is  opened  siowly,  the  plunger  has  practically  no  effect. 
This  plunger  has  an  influence  on  starting,  as  will  be  explained. 

Adjiiatvients.  Carburetors  are  factory  set  «nd  should  need  no 
adjustment  ordinarily,  but  for  different  atmospheric  conditions  a 
slight  change  in  the  air-valve  spring  may  be  needed.  In  the  exterior 
view,  Fig.  122,  this  is  altered  by  turning  the  screw  V.  In  case  the 
carburetor  reall,\'  needs  adjustment,  proceed  as  follows:  Open  the 
throttle  lever  on  the  steering  wheel  about  two  inches,  place  the  spark 
in  the  driving  range  and  start  the  motor;  run  it  until  the  water  jacket 


GASOLINE  AUTOMOBILES  •       177 

be  at  the  extreme  left  when  this  adjustment  13  made.  With  the  spark 
and  throttle  levers  in  this  same  position,  adjust  the  air  valve  screw  V 
again  to  the  highest  motor  speed.  Open  the  throttle  until  the  shutter 
attached  to  the  right-hand  end  of  the  throttle  shaft  just  covers  the  slot 
in  the  carburetor  body  (the  other  side  of  the  carburetor  is  not  shown 
in  either  view).  Then  adjust  the  screw  X  to  the  point  which  pro- 
duces the  highest  engine  speed  or  to  a  point  where  the  engine  slows 
down  slightly  from  a  lean  mixture.  This  screw  also  works  clockwise 
to  give  a  richer  mixture  and  counter-clockwise  for  a  leaner  one. 
During  very  cold  weather,  it  will  be  found  advisable  to  turn  this  screw 
farther  in  a  clockwise  direction  to  give  a  slightly  richer  mixture. 

The  rod  Q  from  throttle  arm  P  to  the  fuel  plunger  is  adjusted 
closely  at  the  factory  and  should  need  no  change  unless  the  carbu- 
retor is  disassembled.  When  reassembling,  the  rod  should  be  ad- 
justed 30  that  its  upper  end  is  flush  with  the  upper  face  of  the  arm  P. 
ftTien  the  carburetor  has  been  used  for  a  long  time,  there  may  be  slight 
wear  at  the  pomt  of  the  inlet  or  where  the  float  needle  D,  Fig.  121, 
rests  on  its  seat.  If  this  should  occur,  the  height  of  the  fuel  in  the 
carburetor  bowl  will  rise.  To*  determine  whether  the  float  is  set 
properly,  remove  the  carburetor  from,  the  engine  and  the  bowl  from 
the  carburetor.  Then  measure  the  distance  from  the  upper  surface 
of  the  float  to  the  metal  surface  above  it,  as  indicated  at  Y  to  Z. 
This  is  measured  best  with  the  carburetor  inverted  and  should  be 
exactly  J  inch.  If  more,  or  less,  the  setting  may  be  corrected  by 
sli^tly  bending  the  arm  to  which  the  float  is  attached. 

Starting,  In  cold  weather,  when  the  engine  will  not  start  imme- 
diately, it  is  not  advisable  to  continue  cranking  the  engine  over  and 
over.  Instead,  open  and  close  the  throttle  rather  quickly  once  or 
twice,  no  more,  with  the  throttle  lever  on  the  steermg  wheel  or  foot 
accelerator.  This  action  raises  and  lowers  the  throttle  pump  at- 
tached to  the  throttle-shaft  arm,  as  previously  explained,  thus  raising 
the  level  of  the  fuel  in  the  float  chamber  so  that  it  is  more  easily 
drawn  up.  If  pumped  more  than  once  or  twice,  too  much  fuel  will 
he  forced  up,  and  this  is  just  as  bad  as  too  little. 

Oxygenerator  Vaporizing  Device.  The  oxygenerator  is  a  new 
device  designed  to  assist  vaporization  and,  in  so  doing,  economize  on 
fuel.  It  is  not  in  itself  a  carburetor  but  is  used  with  a  carburetor — 
any  standard  make — to  generate,  as  its  name  would  iadica'te,  ox'^^il 


178 


GASOLINE  AUTOMOBILES 


which  vaporizes  the  liquid  fuel  more  readily  than  atmospheric  air. 
It  consists,  as  Fig.  123  shows,  of  a  box-like  generator  which  is  fastened 
to  the  top  of  the  exhaust  manifold  by  means  of  chains;  of  a  coil  of 
copper  tubing  to  go  around  the  exhaust  pipe;  and  of  an  extension  of 
this  piping  with  the  proper  number  of  screw  ends  to  be  tapped  into  the 
branches  of  the  inlet  manifold.  The  figure  shows  three  injectors 
for  a  three-way  manifold;  when  tlie  connection  is  made  direct  to 


GASOLINE  AUTOMOBILES 


179 


the  steam  is  superheated.  This  process  of  superheating  develops 
con^derable  pressure,  so  that  the  steam  particles  are  shot  into  the 
mixture,  aiding  materially  in  breaking  it  up,  and  in  this  way  complet- 
ing vaporization.  In  addition,  this  superheating  results,  to  a  certain 
extent,  in  the  decomposition  of  the  water  into  its  elements,  oxygen 
and  hydrogen,  both  of  which  are  highly  combustible.  The  addition 
of  these  greatly  facilitates  the  vaporization  and  combustion  of  the  fuel. 
The  process  is  cumulative;  the  faster  the  engine  runs,  the  more 
heat  there  is  available  for  boiling  the  water  and  superheating  the 


Fi«,  124.     Diacmmniatia  Skclcb,  Showinc  Acliop  of  Oiygfnermtor 

steam.  When  slowing  down  and  stopping,  the  valves  take  care  of  any 
reaction  in  the  other  direction.  The  process  has  a  number  of  features 
which  distinguish  it,  as,  for  instance,  boiling  purifies  the  water  so  that 
all  sedimeot  is  left  in  this  container.  The  clean  burning  of  the  fuel 
is  said  to  eliminate  the  usual  carbon  deposits,  and  the  missing  and 
back-firing,  as  well  as  pre-ignition  which  results  from  carbon.  In  a 
few  certain  instances,  it  is  said  to  have  increased  the  mileage  per 
galloD  of  fuel  on  these  cars :  Marmon,  24  per  cent  with  no  carbon ; 
Oakland,  24  per  cent  with  no  appreciable  carbon  in  4000  miles; 
Bnidc,  27  percent  with  no  carbon  in4000  miles;  Speedwell,  31  percent 
with  PO  (wrbpn  }n  6000  miles;  Case,  Hudson,  and  CadUVac,  eajtii  ^ 


180 


GASOLINE  AUTOMOBILES 


per  cent  with  no  carbon.     In  addition,  it  is  said  to  have  improved  the 
acceleration,  speed,  and  power  in  all  cases. 

Adjustments.  There  are  no  adjustments  beyond  the  valves 
/,  2,  and  3.  It  is  recommended  that  valve  S  should  not  be  touched. 
The  only  reason  for  varying  2  is  to  lower  the  pressure  at  which  the 
valve  pops,  or  opens,  but  the  makers  recommend  that  this  be  kept 
high.  ^'aIve  1  is  adjusted  only  to  increase  or  decrease  the  vacuum 
within  the  tank.  It  is  said  one  turn  of  the  adjusting  screw  at  the  top 
will  create  from  two  to  twenty-one  inches  of  vacuum  within,  so  it 
can  he  seen  that  this  valve  needs  very  little  adjusting. 

KEROSENE  AND  HEAVY  FUEL  CARBURETORS 

Need  for  Heavy  Fuel  Carburetors.  As  has  been  mentioned 
several  times  previously,  and  explained  elsewhere  in  detail,  the 
lighter,  more  volatile  grades  of 
gasoline  are  not  available  in  suf- 
ficient quantities  to  supply  the 
present  demand.  Consequently, 
the  fuel  now  carries  a  consider- 
'  quantity  of  what  was  for^ 


GASOLINE  AUTOMOBILES 


181 


to  8  per  cent;  save  almost  one-half  of  the  engine  lubricant;  give  less 
spark-plug  trouble  and  less  carbonizing;  and  give  a  greater  mileage 
to  the  gallon.  In  doing  these  things,  it  has  these  deficiencies: 
requires  the  use  of  gasoline  for  starting;  and  necessitates  a  material 
reduction  in  compression  pressures. 

As  shown  in  Fig.  125  and  applied  to  a  motor  in  Fig.  126,  the 
float  chamber  is  standard.  Exhaust  gases  enter  at  F,  passing  around 
the  two  vaporizing  tubes  R  and  L,  and  out  at  S.  The  primary  air 
enters  at  /,  is  heated  by  the  exhaust,  and  at  low  speeds  flows  up 
through  the  mixer  tube  R.  This  is  supplied  by  the  nozzle  Q  and,  by 
noting  the  constructions  at  its  upper  end,  it  will  be  seen  that  this 
works  only  until  the  but- 
terfly valve  B  is  opened, 
when  nozzle  K  comes 
into  action.  The  tube  L 
is  corrugated  to  get  the 
greatest  possible  heated 
surface  for  its  length. 
Fig.  126  shows  its  appli- 
cation to  a  motor,  K 
being  the  exhaust  con- 
nection to  the  kerosene 
carburetor  A,  B  the 
gasoline  vaporizer  for 
starting,  and  C  and  D 
its  connection  into  the 
inlet  manifold.  Lever  F  on  the  dash  controls  the  vaporizer,  which 
is  shut  off  after  starting.  The  usual  throttle  connection  to  lever  // 
has  another  connection  to  lever ./  which  operates  an  exhaust  throttle, 
the  idea  being  to  deflect  all  the  gases  to  the  kerosene  carburetor  at 
low  speeds,  but  as  the  throttle  is  opened  and  tlie  engine  speeds  up, 
producing  more  heat,  less  exhaust  gas  goes  to  the  vaporizer.  In 
testing  out  this  device,  the  maker  found  three  necessities,  namely: 
shortest  possible  kerosene  manifold;  shortest  possible  exhaust  heating- 
pipe  connection  A';  and  shortest  possible  gasoline  connecting  tube  C. 

Fore^  Kerosene  Carburetors.  A  large  number  of  firms  in 
different  ports  of  the  world  have  worked  on  this  problem  of  kerosene 
vapoiization.    In  Germany,  the  following  have  done  w,  «.tv&  vq. 


Fie.  I2S.     Method  dI  Applyina  H< 


W  Holiey  K( 
lihsiist  ripii 


182  GASOLINE  AUTOMOBILES 

solving  this  each  has  been  obliged  to  develop  his  own  vaporizer: 
Daimler;  Swiderski;  Maurer;  Adler;  Sleipner  (boats  mostly);  Deutz; 
Banki;  Neckarsulmer  (motorcycle);  Koerting  (fuel  injection);  Kam- 
per;  Diesel  (fuel  injection);  Capitaine  (boats  mostly);  Gardner; 
Dufaux  {Swiss  motorcj'cle) ;  and  others.  Space  prevents  a  descrip- 
tion of  these,  the  Hst  being  given  simply  to  show  that  kerosene  as  a 
fuel  has  attracted  wide  attention. 

In  France  the  same  is  true;  the  Aster  device,  for  instance,  having 
been  so  very  successful  that  it  is  now  made  under  license  in  both 
England  and  Germany, 

In  England  the  Binks,  with  two  jets,  is  designed  to  use  20  per 
cent  gasoline  and  80  per  cent  kerosene  after  starting.  The  Hamilton 
Bi-fuel  has  two  float  chambers,  two  nozzles,  and  other  duplicate 
features.  Tliis  is  designed  for  a  44  gasoline  (petrol)  and  50  kerosene 
(paraffin)  mixture;  on  such  a  mixture,  a  test  of  a  bus  engine  showed 
equal  (rate<!)  power  at  890  r.p,m,;  1  horsepower  more  at  1050;  almost 
3  more  at  1275 ;  and  iit  its  highest  speed  1375  r.p.m.,  Shorsepower  more, 
maximum  output.  The  Kellaway  has  two  fuel  leads,  but  these  use  a 
common  jet.  The  Morris  uses  forced  feed  with  a  constant  air  pressure 
of  4  pounds  per  square  inch  on  the  fuel  tank;  this  is  supposed  to  mini- 
tifuel  lliiw.  and  thu.'-,  as  poiiited  out  in  thedet^ 


GASOLINE  AUTOMOBILES 


183 


builders  of  tractor,  marine,  and  stationary  engines  have  been  more 
or  less  successful  in  vaporizing  kerosene  so  as  to  use  it  advantageously. 
Master  Carburetor.  The  Master  device,  previously  shown  and 
described,  was  designed  primarily  for  the  extra  heavy  fueb,  or  the 
residuum  in  the  distilling  process  called  distillate,  which  is  heavier 
than  kerosene'  and  has  heretofore  been  considered  a  waste  product. 
The  Master  has  utilized  this  successfully  in  actual  service 
for  more  than  four  years.  In  addition,  it  will  handle  kerosene, 
alcohol,  and  other  heavy  fuels,  as  well  as  mixtures  of  all  these  with 
one  another  and  with  gasoline. 


Cli/,  NrM   r«Tk 


Senrab  Carburetor.  In  the  Senrab  device,  shown  in  Fig.  127, 
the  vaporization  of  kerosene  and  heavy  fuels  is  effected  without  the 
use  of  multiple  nozzles;  for  a  single  simple  needle  and  nozzle  with  a 
series  of  small  radial  holes  as  a  fuel  outlet  does  the  trick.  In  the 
figure,  the  fuel  enters  a  float  chamber  A  of  ordinary  design  from 
below,  through  a  simple  removable  strainer.  It  is  then  carried  through 
a  small  bole  B  in  the  side  of  the  float  chamber  nearest  the  vaporizing 
diamber  into  the  vertical  well  C.  At  the  bottom  of  the  well  is 
a  borisontal  passage  D  whieh  communicates  with  the  bottom  q1!^3ia 


....  «■  «^V<1 


13  an  auxiliary  air  valv 
is  sufficient  to  lift  it.     This  admits  i 
inlet  pipe  /,  as  it  affords  a  larger  and  n 
pletes  the  vaporization,  and  the  mixti: 
the  butterfly  type  M  into  the  manifold 

Additional  heat  is  furnished  to  the 
by  exhaust  gases  taken  in  through  the 
vaporizing  chamber  and  nozzle,  then  a 
out  at  0.    This  is  not  heated  air,  but 
temperature,  obtained  by  tapping  int 
three-way  valve  P  is  set  at  the  turn  in  th 
kerosene  passes  from  the  horizontal  pass 
nozzle  lube  E.    Through  the  medium  of 
ing  purposes  is  allowed  to  enter  from  a  sn 
provided  for  this  purpose.    The  valve  c; 
gasoline  only,  kerosene  only,  or  a  mixt 
driver  can  vary  his  fuel  to  suit  himself,  \ 
tions. 

Adjustments.  The  hot-air  throttle  h 
dash  or  steering  post  and  can  be  used  like 
tion.  When  a  richer  mixture  is  needed,  i 
position  as  desired;  and  for  a  leaner  posii 
open  position  a«  ^'*''' — '      ""' 


GASOLINE  AUTOMOBILES  185 

to  the  high  speed.  Run  the  en^e  as  fast  as  possible,  openiiig  the 
needle  valve  gradually  until  the  mATimnm  point  is  reached.  Then 
lock  the  needle. 

Features,  As  will  be  noted,  the  throttle  chamber  K  and  the 
entire  upper  construction  is  made  curcuUr  in  form  where  it  joins  the 
body  and  is  held  in  place  by  simple  machine  screws,  lliis  construc- 
tion allows  the  upper  part  to  be  set  in  any  desired  way.  By  removing 
the  screws,  it  can  be  turned  one  or  more  screw  boles.  Similarly, 
it  will  be  noted  that  the  hot-air  inlet  pipe,  complete  with  its  throttle,  is 
held  in  place  hy  the  exhaust  connection  N,  which  is  screwed  into  the 
carburetor  hody.  By  loosening  this,  the  hot-air  group  can  be  turned 
around  to  any  desired  position,  or  if  more  heat  is  needed,  a  longer 
member  N  allows  a  different  hot-air  connection  /  to  be  used  with  more 
air  apace.  So,  too,  the  three-way  valve  P  b  held  on  by  screws  which 
can  be  taken  out  readily  when  it  is  necessary  to  inspect  or  clean  it 
or  turn  it  to  a  different  position. 

Bennett  Carburetor.  The  Bennett  device.  Type  "C"  of  which  is 
shown  in  section  in  Fig.  128,  is  intended  for  kerosene,  alcohol,  dis- 
tillates, or  other  heavy  fuels,  but  by  a  simple  change  of  the  adjust- 
ments It  can  be  used  for  gasoline.  For  alcohol,  however,  the  makers 
provide  a  special  float,  the  carburetor  remaining  the  same  otherwise. 
It  has  two  needle  valves;  one  projecting  downward  from  the  top  of 
the  device  A,  called  the  slow-speed  needle;  and  the  other,  projecting 
upward  from  the  bottom  B,  called  the  high-speed  needle.  The 
primary  air  for  both  enters  at  C,  passes  around  the  exhaust 
heating  pipe  D,  and  enters  from  helow.  It  rises  around  the  lower 
needle  and  fuel  passage  into  the  chamber  E,  where  the  fuel  is  picked 
up  and  carried  up  into  the  main  vaporizing  chamber  F.  From  here 
it  passes  up  into  the  passage  G,  where  additional  air  comes  in  from 
the  air  valve  H,  after  passing  the  air  throttle  /.  This  dilutes  the 
mixture  and  complete^  vaporization,  and  the  mixture  passes  the  main 
throttle  J  into  the  manifold,  or  engine. 

The  fuel  enters  the  float  chamber  A',  in  which  the  float  is  indi- 
cated, and  passes  from  this  through  the  horizontal  opening  L  to  the 
needles.  As  there  is  hot  air  in  the  passage  just  below  the  opening, 
and  exhaust  gases  in  the  passage  just  above  it,  it  is  subjected  to  a 
considerable  warming  effect.  In  the  center  at  the  bottom,  a  recess 
forms  a  dashpot  for  the  lower  end  of  the  shaft  M,  which  is  connected 


186 


GASOUNE  AUTOMOBILES 


to  the  air  valve  H  at  its  upper  end;  Urn  prevents  nqxd  i 
or  fluttering,  of  this  valve  when  there  is  a  sudden  opening  of  the 
throttle  after  running  at  alow  speeds  The  extra  suction  created  by 
the  3udden  opening*  of  the  throttle  tends  to  jerk  the  auxiliary  air 


m^^i 

l}[JE 

r      i 

g  •    V,     1 p 

W    H     ''■--^^   f 

1 

^■^B 

^J 

1 

1 

p 

^^ 

(f 

^ 

i 

1 

a 

1   ^/ 

t 

~J 

"^-d 

r     I 

&  ^j\ 

1 

1 

k 

. 

\^^    I 

W 

^^ 

!IP®Hlf 

H 

GASOLINE  AUTOMOBILES 


187 


the  medium  of  the  valve  0  attached  to  the  bottom  of  the  small  dash- 
pot  and  the  {dunger  P  which  surrounds  the  bottom  of  the  high-speed 
needle  B.  An  additional  feature  of  the  device  is  an  air  cleaner  Q, 
which  is  shown  at  the  left  in  the  diagram,  Fig.  129.  Its  function 
is  to  clean  all  dust  out  of  the  entering  air  when  the  carburetor  is 
used  on  a  tractor  or  other  unit  which  must  work  in  the  midst  of  con- 
siderable dust.  As  this  dust  is  known  to  filter  slowly  but  surely 
through  the  carburetor  and,  in  time,  reach  the  pistons,  valves,  rings, 
and  bearings,  where  it  does  considerable  damage,  the  utility  of  this 
simple  auxiliary  device,  which  has  no  moving  parts,  is  evident. 

InataUaiion.    Whenever  it  is  possible  to  use  the  air  cleaner, 
install  the  carburetor  with  the  hood  of  the  air  intake  facing  away  from 


B«anett  C«fbufelor 


the  fan  so  as  to  prevent  dirt  from  being  blown  into  it.  Connect  the 
exhaust  manifold  to  the  carburetor,  using  the  three-way  valve  or 
damper  in  such  a  way  that  the  amount  of  gas  can  be  regulated.  When- 
ever possible  the  exhaust  connection  should  enter  the  larger  end, 
because  the  cored  passage  for  heating  the  primary  air  is  there.  Screw 
an  elbow  in  at  the  other  end,  and,  if  required,  a  short  piece  of  pipe, 
to  carry  the  used  exhaust  gases  away  from  the  carburetor.  Connect 
the  water  jet  near  the  bottom  with  the  water  jacket  or  a  small 
auxiliary  water  tank.  This  water  jet  and  its  regulating  needle  can  be 
moved  to  any  desired  position  by  means  of  the  large  nut  R.  The 
needle  is  connected  to  the  dash  so  as  to  be  operated  by  the  driver. 
Two  fud  tanks  are  needed,  one  for  gasoline  to  be  used  tot  s^l^^o^, 


GASOLINE  AUTOMOBILES 


and  ihe  other  for  kerosene  to  be  used  in  regular  running;  they  should 
be  connected  to  the  float  chamber  at  the  bottom  by  means  of  a  three- 
way  valve  or  a  siamesed  pipe,  with  a  shut-off  cock  in  each  line  above 
the  T-connection, 

Adjustment.  There  are  but  two  adjustments,  so-called:  the 
high-speed  fuel  needle  for  full  load;  and  the  slow-speed  fuel  needle  for 
slow  speeds  and  idling.  Both  are  made  by  knurled  nuts,  which  are 
turned  clockwise  to  close  and  counter-clockwise  to  open.  In  the 
process  of  adjusting,  close  the  exhaust  damper  S,  so  as  to  throw  the 
exhaust  gases  through  the  carburetor  and  furnish  the  needed  heat. 
Then  close  the  air-choke  valve  /,  to  make  a  rich  mixture  for  starting 
purposes.  Before  turning  on  the  gasoline,  open  the  high-speed  needle 
B  about  two  turns.  Then  start  the  motor  and  immediately  open  the 
air  choke  valve  /.  If  it  fires  unevenly  after  running  a  little  while, 
close  the  slow-speed  needle  ,1  by  turning  the  knurled  nut  T  to  the 
right,  one  notch  at  artime,  until  the  motor  fires  and  runs  evenly  when 
throttled  down  to  the  slowest  speed.  If  the  motor  hesitates  and  stops 
when  the  air  choke  xaWe  \a  opened,  open  the  slow-speed  adjustment, 
one  notch  at  a  time,  until  the  point  is  reached  at  which  the  motor 
will  Just  run  and  fire  evenly  when  throttled  down. 

RegulMte  the  high-speed  needle  until  the  motor  will  respond  when 


GASOLINE  AUTOMOBILES  189 

should  be  opened.  This  pre-ignition  can  be  detected  as  a  sharp 
metallic  knock  in  the  cylinder.  Only  enough  water  should  be  used  to 
stop  the  knock;  the  carburetor  should  not  be  flooded  with  it.  The  cap 
at  the  bottom,  or  inlet,  of  the  air  cleaner  Q  should  be  kept  tight.  The 
air  cleaner  should  be  emptied  once  a  day,  but  it  should  not  be 
removed  white  the  engine  is  nmning. 

"H  &  N"  Duplex  Carburetor.  The  "H  &  N"  carburetor  is 
called  duplex  because  it  is  designed  and  intended  to  utilize  both 
gasoline  and  kerosene  with  equal  efficiency.     In  this  respect,  it  differs 


from  the  usual  kerosene  carburetor  which  uses  gasoline  for  starting 
purposes  only,  because  it  often  requires  a  change  of  adjustments 
b^ore  the  best  results  are  obtained  when  changing  from  kerosene 
to  gasoline.  A  section  through  the  "duplex"  is  shown  in  Fig.  130. 
In  this  the  float  chamber  is  eccentric  and  in  two  parts  M  for  the  two 
fuels.  These  pass  to  the  nozzle  L  and  to  the  needle,  or  metering 
pin,  D,  through  the  horizontal  passage  R.  The  fuel  to  be  used  is 
detenniiied  through  the  selectmg  plug  N,  controlled  by  the  shift 


ISO 


GASOLINE  AUTOMOBILES 


By  inspecting  this  plug  carefully,  however,  it  will  be  noted  that 
gasoline  only  ia  intended  to  pass  through  the  horizontal  pipe  H,  as 
the  kerosene  passes  out  through  another  passage  S,  then  upward  past 
a  special  kerosene  metering  needle  T  into  the  annular  passjige  U. 
From  this,  a  vertical  annular  passage  ['  of  ver>-  small  dimensions 
leads  upward  and  then  inward  to  the  surface  of  the  Venturi  //,  where 
a  series  of  very  fine  holes  H'  spray  the  kerosene  into  the  vaporizing 
zone.  It  will  be  noted  that  in  passing  from  the  annular  passage  U 
and  the  smaller  passage  V  up  to  the  spraying  holes  H',  the  kerosene 
is  subjected  to  exhaust  heat,  the  relative  heating  surface  being  great 
compared  with  the  small  surface  film  of  fuel.  The  exhaust- 
heating  passage  is  constructed  so  that  the  gases  enterir^  the  lower 
pa.ssage  J  heat  the  inside  surfaces  of  the  kerosene  passage  U  first, 
then  turn  and,  in  passing  through  the  outer  or  upper  passage  /,  heat 
the  outside  surface.  In  this  way  the  maximum  amount  of  heat  is 
obtained. 

The  primary  air  enters  the  bottom  opening  P,  rises  around  the 
nozzle  L,  picks  up  the  fuel  and  partly  vaporizes  it  in  the  Venturi  //. 
then  rises  into  the  passage  or  space  A'  above  this.  Here  additional 
air  enters  through  the  auxiliary  air  passage  C,  the  area  of  which  is 
.'emed  by  the  movement  of  the  compensating  air  valve  F  towanl 


GASOLINE  AUTOMOBILES 


191 


large  carburetors,  this  can  be  ascertained  by  inserting  a  bent  piece  of 
wire  through  one  of  the  air  ports  and  raising  the  valve  to  its  highest 
point  with  it;  then  releasing  it  and  noting  whether  it  sticks  or  drops 
down  again  to  its  nonnal  position.  If  the  valve  sticks,  the  carburetor 
will  not  operate  properly.  In  small  sizes,  half  the  outer  casing  A, 
Fig.  131,  can  be  removed  to  determine  this  point,  which  is  important. 
Bolt  the  exhaust  heat  by-pass  to  the  flange  of  the  exhaust  mani- 
fold, as  the  figure  shows;  insert  the  flexible  tubing  and  fasten  it  by 
means  of  a  piece  of  wire  inserted  through  holes,  which  should  be 
drilled  for  that  purpose.  A  mixture  of  glycerine  and  lithai^,  or 
graphite,  can  be  used  to  make  a  tight  joint.  Provide  a  two^allon 
tank  for  gasoline  and  a  large  tank  for  kerosene.     Run  a  pipe  from 


Ha-  131.     Eiterod  View  ol  "H  Knd  N"  Duplei  Ckibuntor,  Sbowioc  AdiuatnieotB 

the  kerosene  tank  to  the  union  below  the  kerosene  compartment  in 
the  carburetor  and  a  similar  pipe  from  the  gasoline  tank  to  the  gaso- 
line compartment.    Make  all  joints  leak'proof  with  red  lead  or  shellac. 

Siarting.  Close  the  throttle  lever  and  start  on  gasoline.  The 
fuel-shift  lever  in  the  sketch  is  shown  for  kerosene  fuel;  for  starting, 
it  should  be  thrown  to  the  opposite  position.  Let  the  device  run  for  a 
few  minutes  until  it  becomes  heated.  The  fuel  jet  control,  lever 
BB  at  the  bottom  of  the  carburetor,  which  controls  the  position  of  the 
nozzle  L,  is  set  closed  at  the  factory,  so  open  this  a  half  turn  before 
trying  to  start. 

AdjuatTTienis.    With  the  lever  in  this  positioii,  an  extremely  ' 
ridi  mixture  will  be  formed,  so  turn  the  lever  back  in  the  direction  of 
doeed  until  the  best  running  at  slow  speed  results.    J\»t  \)^*3W 


192 


(JAHOHNE  AUTOMOBILES 


making  the  shift  from  gasoline  to  kerosene,  open  the  jet  sli^tly; 
after  shifting;  to  kerosene  shift  back,  but  not  necessarily  to  the  same 
amount.  For  high  speed,  screw  the  vacuum  relating  screw  B  all 
the  way  in,  a<lvaiice  the  spark,  and  open  the  throttle  wide;  if  the  carbu- 
retttr  buck-fires,  unscrew  the  needle  B  a  very  little  at  a  time  until  the 
back-firing  ceases,  or  until  the  motor  runs  satisfactorily.  Lock  with 
the  knurled  nut  after  each 
adjustment.  Do  not  at- 
tempt to  make  high-speed 
adjustments  with  the  lever 
BB.  Do  not  stop  the 
motor  when  running  on 
kerosene;  always  shift  to  ' 
gasoline  in  order  to  insure 
a  gasoline  mixture,  which 
means  easy  starting  the 
next  time. 

Deppe  GasQenerator. 
Althougli  not  called  a  car- 
buretor by  its  maker,  the 
:enerator  re- 


GASOLINE  AUTOMOBILES  193 

kerosene,  naphtha,  etc.,  and  mixtures  of  these;  fixed  metering  adjust- 
ment which  is  not  affected  by  altitude,  temperature,  or  location;  easy 
starting;  less  vibration  of  en^ne;  and  others. 

Id  Fig.  132,  the  fuel  enters  the  fioat  chamber  A  from  below  and 
passes  through  a  horizontal  passage  B  from  which  the  two  nozzles 
lead  upward.  The  low-speed  nozzle  C  draws  its  heated  air  through 
the  primary  intake  D  and  mingles  with  this  in  the  modified  Yenturi  E. 
When  the  engine  demands  more  fuel,  it  is  supplied  by  the  high-speed 
nozzle  F,  which  gets  its  air  from  the  auxiliary  air  valve  G;  this  air  and 
fuel  mixture  combine  with  the  other  in  the  chamber  H,  just  above 
the  Venturi  and  just  below  tlie  center-opening  throttle  /.  Up  to 
this  point  it  is  not  radically  different  from  the  average  two-jet  car- 
buretor with  the  auxiliary  air  valve. 

However,  in  the  chamber  just  above  this  a  mechanical  atomizer, 
or  rotating  mixer  on  ball  bearings  J,  is  inserted.  The  idea  is  to  com- 
bine the  air  and  fuel  particles  more  intimately  through  the  rotation 
of  this  mixer  within  the  zone  of  vaporization.  The  actual  vaporizing 
chamber  K  is  next  above  this.  It  is  an  annular  passage  around  the 
highly  heated  exhaust  gas  chamber  L,  but  inside  of  the  outer  exhaust 
chamber.  This  insures  the  absolute  completion  of  the  gasification 
started  in  other  chambers,  so  that  the  mixture  passing  into  the  gasi- 
fication chamber  M  at  the  top  and  thence  into  the  inlet  manifolds 
and  cylinders  is  sure  to  be  a  pure  dry  gas. 

Starting.  To  assist  in  starting,  the  primary-air  passage  is  fitted 
with  a  choke  valve  of  the  butterfly  tj^pe,  which  closes  off  this  passage 
entirely  so  as  to  produce  a  rich  mixture.  -Across  the  middle  of  the 
lower  vaporizing  chamber  H,  an  electric  resistance  wire  or  heating 
coil  is  strung.  The  coil  is  connected  to  the  starting  battery.  The 
connection  is  made  so  that  the  current  passes  through  this  heating 
coil  as  soon  as  it  is  turned  on.  This  supplies  the  cold  carburetor  with 
the  equivalent  of  the  exhaust  gas  heat,  which  is  available  shortly 
after  the  engine  has  been  started. 

Adjuatmenis.  As  will  be  seen  from  the  illustration,  the  low-speed 
nozzle  and  air  opening  are  fixed,  the  only  possible  adjustment,  setting, 
or  change  being  in  the  alteration  of  the  nozzle  or  in  the  quantity  of 
primary  air  admitted.  The  high-speed  nozzle  is  fixed  similarly  so 
that  it  cannot  be  adjusted,  the  high-speed  air  valve  G  furnish- 
ing the  only  adjustment.    The  adjustment  of  this  is  very  «\m\iV&'i 


194  GASOLINE  AUTOMOBILES 

with  the  engine  running,  advance  the  spark  pretty  well  to  the  limit, 
open  the  throttle  lever  to  its  maximum,  and  then  vary  the  position 
of  the  nut  JV  which  governs  the  tension  of  the  spring  0  to  the  point 
where  the  maximum  speed  of  rotation  is  obtained.  This  setting  should 
be  checked  against  actual  high-speed  running  on  the  road,  as  there  is 
usually  a  difTerence  between  the  best  road  high-speed  setting  and  the 
best  engine-speed  setting,  with  the  car  standing  on  the  garage  floor. 

CARBURETOR  TROUBLES  AND  REMEDIES 
Engine  Should  Start  on  the  First  Turn.  In  starting  a  car  or  any 
engine,  whether  located  in  a  car  or  not,  everj'thing  should  be  inspected 
so  as  to  know  if  all  is  right  before  attempting  a  start.  With  the 
novice,  this  is  somewhat  of  a  task,  but  to  the  old  hand  it  is  so  much 
of  a  routine  task  that  he  does  it  unconsciously.  If  all  conditions  are 
right,  the  carburetor  is  primed  and  the  engine  will  start  on  the  first 
turn  of  the  crank.  If  it  does  not  do  so,  there  is  a  source  of  trouble 
which  must  be  remedied  first,  and  it  is  useless  to  continue  cranking. 
The  trouble  may  lie  iii^the  fuel  system  itself,  but  exterior  to  the 
vaporizer,  or  it  may  be  in  the  ignition  apparatus.  It  is  well  in  a  case 
of  this  wort  tu  start  with  the  gasoline  tank  and  follow  the  fuel  through 


GASOLINE  AUTOMOBILES 


195 


remedy  this,  the  method  of  procedure  is  as  follows:  Shut  off  the  cock 
below  the  tank  so  that  none  of  the  previous  liquid  can  escape,  then 
drain  off  the  carburetor  and  pipe  into  a  handy  pail.  Next,  open  the 
union  below  the  cock  in  the  feed  line  and  the  one  at  the  other  end  of 
the  same  pipe.  At  both  places  look  for  o.bstruction.  Then  clean  the 
pipe  out  thoroughly,  using  flowing  water,  a  piece  of  wire,  or  other 
means  which  are  available  at  the  time. 

Gasoline  Strainer  a  Source  of  Trouble.  If  you  find  nothing  here, 
look  in  the  strainer  of  the  carburetor  to  make  sure  that  the  flow  is  not 
stopped  there  by  the  accumulation  of  dirt  and  grit,  filtered  out  of  the 
fuel.  The  strainer  should  be  cleaned  often,  but,  like  many  other  dirty 
.  jobs,  it  is  postponed  from  time  to  time. 

Should  this  source  of  trouble  prove  "not  guilty"  the  carburetor 
itself  becomes  an  object  of  suspicion.  Is  the  fioat  jammed  down 
upon  its  seat,  or  are  there  obstructions  which  prevent  the  flow  of  fluid? 
Is  the  float  punctured,  or  has  one  of  the  soldered  joints,  if  a  metal  one, 
opened,  or  is  it  fiiel-soaked,  if  cork? 

Bent  Needle  Valve-Stem.  To  attend_  to  this  sort  of  trouble, 
disconnect  the  priming  arrangement,  take  the  cover  off  the'  float 
chamber  (it  usually  is  screwed  on  with  a 
right-hand  thread)  and  take  the  float  out. 
An  examination  of  the  float,  Fig.  1.3^, 
will  disclose  whether  it  is  at  fault  in  any 
of  the  above-mentioned  ways,  all  of  whicli 
are  comparatively  easy  to  fix.  If  the  float 
was  jammed  down,  perhaps  by  priming, 
the  act  of  taking  it  out  will  loosen  it, 
provided  that  the  stem  of  the  float  is  not 
bent,  and  the  needle  valve  or  its  seat  is 
not  injured.  If  the  seat  is  scored,  it  should 
be  ground-in  just  like  any  other  valve, 
usmg  oil  and  tine  emery.    A  fuel-soaked 

cork  should  be  thrown  away  if  another  is  at  hand  to  replace  it,  but  if 
not,  the  cork  float  should  be  mo\'ed  in  its  position  on-  the  stem  so  that 
it  sets  higher  in  the  liquid.  In  other  words,  move  the  cork  up  suffi- 
ciently to  compensate  for  its  loss  of  buoyancy. 

In  case  of  a  punctured  metal  float  or  of  loose  solder,  the  only 
real  remedy  in  either  case  is  to  resolder.    It  usually  happens  VXv&V  ». 


196  GASOLINE  AUTOMOBILES 

soldering  outSt  is  not  available  out  on  the  road,  and  some  foim  of 
makeshift  will  be  necessary  in  order  to  reach  a  place  where  one  may 
be  had.  "If  the  puncture  is  oo  the  bottom,  it  is  sometimes  possible 
to  accomplish  this  by  inverting  the  float  so  that  the  hole  comes  at  the 
top  where  the  gasojine  seldom  reaches  it.  If  the  flow  be  reduced  to 
make  sure  that  the  float  will  not  fiU  up,  it  is  possible  to  reach  a  place 
where  a  soldering  iron  may  be  procured. 

A  remedy  which  might  be  tried  in  an  extreme  case  of  this  sort  is 
to  fill  the  float  to  make  it  heavy,  so  that  it  will  have  a  tendency  to 
sink.  Then  take  a  spring  of  small  diameter,  cut  off  a  short  piece  and 
place  it  in  the  float  chamber  so  that  it  opposes  the  sinking  action 
of  the  now  heavy  float.  By  carefully  determining  the  length  and 
the  strength  of  this  spring,  the  same  action  is  obtained  aa  if  the  float 
were  working  all  right.  If  the  entrance  of  the  liquid  fuel  is  such  that 
the  sinking  of  the  heavy  float  tends  to  close  rather  tbao  open  the  gaso- 
line inlet,  the  spring  would  have  to  be  on  the  bottom  and  fairly  strong 
so  as  to  oppose  the  action  of  gravity.  But  if  the  float  works  down- 
ward to  open  the  gasoline  passage,  the  spring  will  be  at  the  botttun 
and  very  weak  being  there  simply  to  prevent  an  excessive  flow. 

Throttle  Loose  on  Shaft.    Now  the  carburetor  trouble  has  been 


GASOLINK  Ai;TOMOHIfJX 


where,  take  tfaia  off  in  neart^U  of  tni^pl»<iil  wm^.i<'  or  niiitiUir  ■■. 
>t8nces.  The  size  of  the  pipe  i<t  nw-h  that  trn;,  tliioj;  in  it  Uir^i^  citoi 
to  cause  trouble  may  \)e  iri>.tat)tly  yft-n  uinl  niinr/ti\.  'i'}^.  i, 
exception  to  tbU  a  a  Amkll  hok  in  tli':  ifiW-pij^i;  fa>ii;j/.  r-hif  d 
c-l':-£z*ti  ev«i  »hh  a  ;train  of  -lan*!  or  oi.h<-f  ff>;)i/'n;(L  v.j;)  /,/,•  o 
«-.:;*■  tru-/j*r  -xTiii  ti.^  mixture  at  all  tUi,'-.,  l,j'.  mJI  Jiiv,  1^  , 
LaH  :-;■  £i/i-  ^tk-'ilirlv  if  it  LajjI^-m  t/,  F>- ./  if ,  ..»,*„  »;.</w 
Tl't  vt:-.*.  «  cry.K,  '?^.':.*',;;.-r.^  *.}.f.  fl//*  «,'  i,-,  ,^:  !•■/'.■.  »•*  »- 

-;^T«^-     I*  "_■' t".  .■-*.-:  i;.-;  .V.  ^■". '^  •  y'   v, ''i'  ■.-. /^rj-f  ?v 


198  GASOLINE  AUTOMOBILES 

motor  will  give  better  power  and  run  faster  with  the  throttle  partly 
closed  than  when  wide  open.  This  happens  when  the  auxiliary  air 
valve  does  not  open  sufficiently  to  admit  the  large  quantity  of  air 
needed  at  the  widest  throttle  opening.  The  mixture,  therefore, 
becomes  too  rich,  and  the  motor  starves.  The  auxiliary  air  valve 
usually  has  an  outside  spring,  the  tension  of  which  is  controlled  by  a 
milled  nut,  also  on  the  outside.  Then,  when  it  is  desired  to  make  a 
change  in  the  mixture,  the  nut  is  turned,  altering  the  tension  of  the 
spring  and  thus  altering  the  lift  of  the  air  valve;  in  this  way  the 
proper  amount  of  air  is  admitted.  To  admit  more  air,  the  nut  is 
backetl  off  in  onlcr  to  weaken  the  tension  and  thus  allow  the  air  valve 
to  o[>en  wider.  To  admit  less  air,  the  spring  tension  must  be  increased 
so  that  the  air  vahe  cannot  open  quite  so  far  or  stay  open  so  long. 
Ailjii-ifmriil.t  for  Heating  Water  and  Air  Supply.  On  a  large 
number  of  carburetors  there  are  two  more  adjustments:  those  for 
heating  the  water  and  those  for  heating  the  air.  The  general  run  of 
carburetors  are  now  water- jacketed  to  help  \aporize  the  heavy  fuels; 
during  warm  weather  this  may  supply  too  much  heat.  For  this 
mison,  a  cock  is  generally  fitted  to  the  hot-water  line,  which  will  allow 
partial  as  well  as  total  closure. 

ilarlv,  lii)t  iiir  is  supplie<l  to  almost  all  carburetors  to  vapor- 


GASOUNE  AUTOMOBILES 


199 


If  you  are  ever  bothered  in  this  way,  you  may  be  sure,  granting 
that  the  spark  b  good,  that  the  trouble  lies  in  the  fuel  system.  From 
the  description  of  the  trouble,  it  appears  as  if  conditions  were  such 
as  to  starve  the.  engine,  although  this  was  doubtless  done  uncon- 
sciously. This  action  is  due  to  the  fact  that  the  gasoline  level  has  been 
lowered  so  far  that  the  suction  of  the  engine  does  not  draw  up  sufficient 
fuel  for  running.  The  fact  that  you  have  to  prime  to  start  and  then 
prime  to  keep  going,  even  this  priming  failing  to  work  sometimes, 
would  seem  to  prove  that  the  engine  is  not  getting  enough  fuel.  The 
trouble  is  that  the  spray  nozzle  has  been  raised  too  high,  so  that  the 
gasoline  level  is  fom-  or  five  times  as  far  below  the  nozzle  as  it  should 
be.     The  engine  suction  must  raise  the  gasoline  this  distance  before 


.,     KinB  V»ri»tion  o(  Noiils  Level.     Fitit  Picure,  Correct: 

UccDDd.  Too  Low— Eniine  Will  Flood:  Third,  Too  High— Eo^oe  Will  Stuvo 

any  of  the  fuel  will  get  into  the  cylinder,  and  if  the  distance  exceeds  the 
height  to  which  the  suction  can  raise  the  fuel,  none  will  pass  over.  In 
a  case  of  this  sort,  priming  only  helps  temporarily. 

Wrong  Adjastment  of  Jet  Nozde.  The  wrong  location  of  the  jet 
nozzle  results  when  the  fuel  level,  as  fixed  by  the  float,  \s  not  high 
enough  to  give  the  proper  flow  of  fluel  into  the  vaporizing  chamber. 
Drivers  who  have  trouble  with  this  are  frequently  puzzled  by  it, 
because  they  assume  that  the  carburetor  is  properly  adjusted  before 
•  leaving  the  factory.  This  is  not  always  the  case.  One  young  driver 
said: 

What  is  the  cause  of  this  very  piuzling  knock?  My  fouT-cylinder  engine 
develops  a  bad  knock  on  &  hill,  which  can  only  be  elinUDatri  by  retarding  the 
■park,  but  when  that  is  done,  the  engine  "dies",  that  is,  gives  no  power.  The 
^ect  is  the  same  on  level  roads  when  the  throttle  is  opened  more  than  one 
third.  I  may  have  deranged  the  level  o(  the  gasoline  within  the  carburetor 
Would  that  have  this  result? 


200 


GASOLINE   AUTOMOBILES 


Now,  tliia  trouble  is  directly  traceable  to  the  change  in  the  level 
of  the  nozzle  made  when  cleaning  and  is  made  unconsciously.  To 
quote  from  a  plain  statement  of  the  effect  of  this  change: 

B)  raising  the  spray  nozzle,  you  lower  the  level  of  the  gaaolioG  relatively. 
Therefore,  the  liquid  ia  less  sensitive  to  the  suction,  which  would  reduce  the 
iLmount  of  gasahne  used.  At  low  speeds,  there  would  be  a  tendency  to  atan't 
(hf  eiiffiTie,  which  uvuld  he  mont  noticeable  on  hilln. 

The  trouble  is  that  the  spray  nozzle  has  been  raised  so  that 
the  tiiKine  does  not  get  enough  fuel  at  slow  speeds  and  on  hills. 
By  lowering  this  a  small  amount.  Fig.  I."i4,  the  engine  will  be  able  to 
suck  up  more  fuel  ami  the  trouble  ceases  with  the  change.  In  making 
this  change,  be  careful  not 
to  lower  the  nozzle  too 
much  at  once,  as  the  effect 
then  is  just  as  bad,  the 
carburetor  flooding  at  the 
slightest  provocation.  The 
better  way  is  to  lower 
the  nozzle  a  very  slight 
amount,  say  one-quarter 
of  a  millimeter,  or  perhaps 


GASOLINE  AUTOMOBILES 


201 


care  being  in  starting  it.  As  the  amount,  or  length,  of  the  needle  point 
within  the  tapered  seat  is  small,  the  float  need  be  raised  but  a  small 
amount  to  clear  that.  Then,  it  may  be  lifted  out  as  one  desires,  since 
it  usually  is  made  from  a  half  inch  to  an  inch  smaller  in  diameter 
than  the  chamber  within  which  it  works. 

Smallest  Detail  Important.  The  influence  of  the  smallest  things 
may  be  of  great  importance,  as  illustrated  in  Fig.  136,  A  man  having 
a  small  runabout  with  a  rather  large  air  vent  in  the  gasoline  tank, 
which  was  located  directly  over  the  engine,  was  bothered,  in  climbing 
bills,  by  too  rich  mixtures.  These  not  only  caused  the  engine  to 
smoke  badly,  but  caused  a  lack  of  power.     On  investigation,  he  found 

that  the  carburetor  was 

located  below  and  nearly 
underneath  the  gasoline 
tank.  On  a  hill,  the 
gasoline  flowed  out  of 
the  air  vent,  down  the 
side  of  the  tank,  and 
dropped  into  the  air  in- 
take, thus  increasing  the 
mixture.  Obviously  the 
cure  for  this  was  to 
change  the  air  intake  so 
that  the  overflow  from 
the  tank  could  not  drop  , 
into  it  or  into  any  part 
of  the  carburetor.  The 
sketch,  Fig,  136,  shows  howhewas  advised  to  change  it;  the  comment 
on  the  trouble  and  the  proposed  change  were  as  follows: 

The  addition  of  fuel,  as  you  describe,  to  the  air  at  the  air  inlet 
will  seriously  disturb  the  running  of  the  engine  and  probably  give 
so  rich  a  mixture  as  to  choke  the  engine.  It  is  advisable  to  remedy 
this  at  once,  and  the  best  way  to  do  so  is  to  prolong  the  present  air 
inlet  upward  and  outward  away  from  the  gasoline  tank  which  causes 
the  trouble.  To  do  this,  have  a  sort  of  stove  pipe  made  of  galvanized 
iron,  tin,  or  any  similar  metal.*  It  should  be  long  enough  so  that  its 
top  is  as  high  as  the  top  of  the  offending  tank,  then  make  a  big,  easy 
bend  away  from  the  latter.   The  opening,or  mouth.of  the  pipe  should 


Fi«.  13S.     Puiiling  Ci>rbur«tor  Problem  Sotved 


GASOLINE  AUTOMOBILES 


he  30  formed  as  to  take  a  screen,  which  is  necessary  to  keep  out  the 
dust  and  should  preferably  he  made  removable,  so  that  when  the 
screen  clogs  with  dust  it 
can  be  taken  otf,  cleaned, 
and  replaced.  For  this 
purpose  use  a  very  fine 
brass  gauze,  which  can  be 
obtained  at  anyhardware 
store  at  small  cost. 

Pre-Heating  the  Air. 
One  thing  that  gives  a  lat 
of  trouble  is  the  heavier 
fuel  now  supplie<i .  It 
can  he  used  successfully  only  by  adding  heat,  the  application  of 
which  may  take  one  of  two  forma:  a  water  or  exhaust-gas  jacket 
around  the  carburetor,  or  an  arrangement  pre-heating  the  air  supply, 
The  furnicr  liiiiiiii!  be  jiddcd,  but  the  latter  can  very  easily.  This  is 
done,  as  shown  in  Fig.  1.S7.  by 
running  to  the  air  Inlet  for  the 


GASOLINE  AUTOMOBILES  203  " 

the  carburetor.  In  Fig.  13S  is  an  English  example  of  this,  showing 
the  carburetor  connections  on  the  four-cylinder  Belsize.  The  pipe 
at  the  left  is  the  inlet  manifold  and  the  one  at  the  right,  the  hot-air 
pipe  from  exhaust  manifold  down  to  air  inlet.  In  all  cases  this 
hot-air  connection  is  made  as  short  as  possible. 

Causes  of  Misfiring.  There  are  a  number  of  vexatious  things  to 
make  the  novice  and  prospective  driver  peevish.  Chief  among  these 
is  the  trouble  known  as  misfiring.  This  may  be  described  as  a  failure 
of  the  mixture  to  fire  in  any  one  cylinder.  It  is  usually  due  to  igni- 
tion, so  that  the  term,  as  used  now.means  a  failure  to  fire  a  charge  due 
to  an  electrical  cause.  However,  there  are  manj'  common  misfires 
which  are  due  equally  as  much  to  a  failure  in  the  fuel-supply  system, 
so  that  the  latter  meaning  attached  to  the  word  is  a  misnomer. 

Among  the  causes  which  contribute  to  misfiring  may  be  men- 
tioned ignition  troubles,  such  as  short-circuit  in  wires,  exhausted 
battery,  pitted  or  improperly  adjusted  vibrators  of  the  coil,  sooty 
or  cracked  plugs,  loose  connections  or  switch,  dirty  timer  or  com- 
mutator, punctured  condenser,  moisture  in  cpil,  wet  wires  or  cables, 
water  on  distributing  plate,  dirt  or  wear  on  contacts  in  distributor, 
or  dirt  or  wear  in  timer. 

Then,  there  are  the  misfires  due  in  part  or  wholly  to  the  fuel  or 
carburetion  sjstem.     These  may  be  grouped  or  listed  as  follows : 

CarburetUm.  and  Fuel.  Faulty  mixture,  sediment,  or  water  in 
the  carburetor,  clogged  gasoline  strainer,  leaky  float,  clogged  spraying 
nozzle,  bent  float-valve  spindle,  stale  gasoline,  partial  stoppage  of 
fuel-supply  pipe,  hole  or  obstruction  in  intake  pipe  or  manifold — 
these  are  not  all  the  things  that  might  happen,  but  are  the  principal 
ones  which  the  miter's  experience  has  suggested  as  most  likely  to 
occur  to  cars  in  general. 

Foremost  among  the  several  difficulties  which  may  be  called  ' 
common  misfires  is  the  lack  of  a  proper  mixture.  A  rich  mixture 
containing  a  relatively  large  proportion  of  gasoline  in  proportion  to 
air  is  never  desirable,  inasmuch  as  it  deposits  considerable  soot  upon 
the  piston,  cylinder  walls,  and  valves,  and  is,  moreover,  a  waste  of 
fuel.  The  motor  will  seldom  run  well  on  a  very  rich  mixture,  and 
the  carburetor  should  be  so  adjusted  that  no  more  gasoline  is  fed  to 
the  mixing  chamber  than  is  sufficient  for  the  motor  to  develop  its 
full  power.    The  exact  mixture  may  be  found  by  experiment. 


204  G.VSOLINE   AUTOMOBILES 

A  very  rich  mixture  will  cause  misfiring;  the  motor  will  have  a 
tendency  to  choke  at  other  than  high  speeds  and  is  hkely  to  overheat. 
A  lean  or  too  thin  mixture  will,  on  the  other  hand,  lower  tiie  efficiency 
of  the  motor,  giving  it  a  marked  tendency  to  miss  at  high  speeds, 
and  is  also  accompanied  by  a  popping  soimd  in  the  carburetor.  In 
this  case,  the  needle  valve  should  be  adjusted  to  admit  more  gasoline, 
or.  if  due  to  an  excessive  supply  of  air,  the  auxiliary  air  valve  should  be 
adjusted  to  admit  less  air. 

Bent  Float  Spindle.  A  bent  float  spindle  will  cause  missing  in 
one  or  more  cylinders.  The  float  spindle  may  become  bent  or  it 
may  become  jammed  into  its  seat  by  too  vigorous  priming.  This 
may  be  discovered  by  unscrewing  the  cover  and  lifting  out  the  float. 
Considerable  care  should  be  taken  in  straightening  out  a  bent  spindle, 
and  the  metal  should  be  placed  upon  a  block  of  hard  wood,  another 
block  interposed,  and  the  spindle  gently  tapped  with  a  hammer. 

Leaky  Float.  A  leaking  metal  float  or  a  fuel-logged  cork  will 
cause  missing,  owing  to  its  uncertain  and  erratic  action,  A  cork  float 
should  be  thoroughly  dried  out  and  then  given  a  couple  of  coat3  of 
shellac  to  prevent  it  from  absorbing  the  gasoline.  As  a  new  float 
is  not  at  all  expensive,  the  driver  will  probably  find  it  more  convenient 


GASOUNE  AUTOMOBILES  205 

I  Summary  of  Qasoline  System  Troubles 

buretors  should  be  among  the  \:\-^t  things  to  change  in  case  of 
A  black  smoke  from  tlie  exhnu^t  will  iinliratc  too  rich  a 
Too  thin  a  mixture  may  cause  back-firing  through  the 
or. 

iding  oi  Carburetor.  This  may  be  due  to  the  failure  of  the 
alve  to  seat  pro5>erly,  which  may  be  corrected  by  grinding 
i;  or  to  a  punctured  float  which  must  be  removed  and  the  hole 
■  soldered.  It  may  also  be  due  to  the  spraying  nozzle  being 
led  that  the  opening  is  below  the  gasoline  level.  To  remedy, 
:  Dozzle  by  easy  steps  until  the  correct  level  is  obtained. 
log  of  Gasoline  Tank.  This  should  never  be  done  by  lamp 
*n  light. 

ks  in  Qasoline  Line.  These  must  be  repaired  as  soon  as 
ed.  They  may  result  in  fire,  destroying  the  ear  and  endanger- 
ives  of  its  occupants. 

w  Cap.  The  filler  cap  should  uncover  an  opening  in  which 
ner  of  gauze  wire  which  should  not  be  taken  out,  or,  if  broken, 
1  be  replaced  promptly.  As  an  additional  protection  against 
►reign  particles  getting  into  the  gasoline  system  a  funnel 
chamois  skin  through  which  the  gasoline  may  be  poured 
>e  used. 

ide  of  Gasoline.  For  ordinary  use,  gasoline  from  56  to  68 
test  is  most  satisfactory.  The  former,  called  also  stove 
,  is  the  only  kind  obtainable  now. 

(trucUon  In  Needle  Valve  Jn  Carburetor.  In  searching  for 
d  gasoline  line,  it  is  well  to  unscrew  the  needle  of  the  needle 
id  then  blow  through  the  vatve.  This  will  remove  particles 
hat  may  be  there. 

LET  MANIFOLD  DESIGN  AND  CONSTRUCTION 

iflges  in  Manifold  with  Engine  Developments.  Notwith- 
;  the  marked  attention  paid  to  minor  details  of  design  in  the 
«  or  four  years,  manufacturers  have  had  no  greater  problem 
at  of  vaporizing  the  fuel  properly,  quickly,  and  efficiently; 
led  to  considerable  attention  being  given  to  inlet-manifold 
Id  the  beginning,  the  inlet  was  a  plain  straight  '^vecfc  o\ 


GASOLINE  AUTOMOBILES 


GASOLINE  AUTOMOBILES 


207 


tubing  from  what  corresponded  to  the  carburetor  to  the  hole  in  the 
cylinder  leading  to  the  combustion  chamber  via  the  inlet  valve. 
With  the  development  of  the  four-cylinder  motor,  the  majority  of 
these  were  cast  in  pairs,  and  the  pipe  assumed  a  plain  or  modified 
Y-shape.  Even  at  that,  there  was  considerable  chance  for  variety, 
as  will  be  noted  in  the  nine  dif- 
ferent forms  shown  in  Fig,  139. 
Changes  from  Fours  to 
Sixei.  With  the  coming  into 
popularity  of  the  six-cylinder 
form  of  motor,  the  inlet  mani- 
fold received  renewed  atten- 
tion ;  for  now  there  were  more 
variables,  and  it  was  a  question 
of  the  best  combination  of 
them.  One  solution  of  this,  as 
seen  on  a  medium  sized  block 
six,  is  illustrated  in  Fig.  140. 
Here,  the  distance  which  the 
fuel  must  travel  to  the  two 
central  cylinders  (cylinders  S 
and  4)  is  so  much  less  than  the 
distance  which  the  gases  must 
travel  to  either  1  and  ^  at  the 
front  or  S  and  6  at  the  rear  , 
that  there  was  the  possibility 
of  these  four  cylinders  being 
somewhat  starved.    To  com- 

,  pensate.  for  this,  the  central 
part  of  the  manifold  where  the 
three  [»pes  to  the  cylinders  join    fu.  ui    vnnrtyof  iniet  Miinifoidi  r»d  on  sii- 
that  from  the  carburetor  was      co,rf«»./  .v.  ir  lUiui  PMUkin,  co^rant. 
made  much  larger,  with  the 
idea  of  providing  a  well,  or  reservoir,   for  gaseous  mixture  large 

■  enough  so  the  two  central  cylinders  could  not  use  all  its  contents. 
The  majority  of  designers,  however,  preferred  to  make  the  dis- 
tance for  the  gases  the  same  in  each  case,  which  led  to  some  of  the 
shapes  seen  in  Fig.  141.    Here  it  will  be  noted  that  a  centce.V  \qo^  S.?. 


GASOLINE   AUTOMOBILES 


used  to  make  these  distances  come  out  etiiial  in  all  but  one  case;  in 
that,  the  cylinders  are  cast  in  threes  with  a  single  inlet  for  each  group. 
Changes  for  Eights  and  Twehes.  The  coming  of  the  V-tj'pe 
motors,  both  eights  and  twelves,  has  had  another  influence;  for  thej' 
came  at  the  time  when  fuel  was  getting  heavier  and  heaner. 
Designers  were  beginning  to  recognize  the  difiiculty  of  vaporizing  all 
the  heavy  fuel  before  it  reached  the  cylinders,  and,  to  assist  in  this, 
they  began  utiliziiig  the  manifold.  Consequently,  the  majority, 
if  not  all,  the  eight- and  twelve-cylinder  engines  have  manifolds  of  tlie 


GASOLINE  AUTOMOBILES 


Heating  the  Charge.    The  method  of  heating  the  charge  has 
taken  a  number  of  forms.    In  a  simple  four-cylinder  motor  of  the 


[mprovM  Vsporiutial 


L-faead  type,  like  the  Ford,  it  has  been  possible  to  develop  a  combina- 
tion inlet  and  exhaust  manifold  (a  single  casting  which  would  replace 
both  of  the  former  manifolds)  which  would  give  the  heating  effect 
desired  in  the  inlet  portion.  Fig.  143  shows  one  way  in  which  this 
is  done  and  shows  the  central  plate,or  rib, between  the  two  manifolds, 
which  is  heated  to  a  high  temperature  by  the  exhaust  gases,  and  thus 


has  a  large  influence  on  the  final  vaporization  of  the  inflowing  gases 
OQ  the  other  sade  of  it.     It  is  clwned  for  this  form  that  it  will  9a.N«. 


310  GASOLINE  AUTOMOBILES 

from  25  to  40  per  cent  of  the  fuel  used,  and,  even  though  {Ids  duin  ii 
not  borne  out  in  all  cases,  the  fact  that  th«e  is  a  saving  shows  tiiat 
this  is  a  correct  method.  Many  of  the  more  modem  motors  are  not 
only  incorporating  this  as  a  method  of  saving  fuel  and  increa^ng  the 
motor's  efficiency,  but  also  of  reducing  the  number  of  parts  in  the 
machine,  the  opportunities  for  trouble,  and  pos^bly  of  reduong 
weight.    A  secondary  thought  is  the  reduction  in  manufacturing  cost 

Another  way  in  which  the  ordinary  fout^  and  aix-cylinder  inlet 
manifold  has  been  altered  is  by  the  addition  of  the  water  jack^ 
previously  mentioned  for  the  V-types.  A  typical  example  of  this  is 
seen  in  Fig.  144,  which  shows  a  water-j^keted  inlet  manifold  on  a 
six-cylinder  motor,  although  the  water-pipe  connections  are  not  visible. 

Qianges  in  Construction  of  Manifold.  In  addition  to  the  de«gn, 
the  construction  of  inlet  manifolds  has  been  of  marked  influenoe. 
Thus  a  manifold  of  aluminum,  iron,  or  other  cast  metal  is  usually  quite 
different  from  what  a  manifold  for  the  same  engine  would  be  if  made 
from  copper  or  steel  tubing.  In  addition  to  the  limitations  of  the 
process  of  production,  there  would  be  the  changes  which  the  surface 
produced  would  have.  Thus,  a  casting  would  have  a  more  or  less  * 
rough  surface,  while  a  drawn  tube  would  be  perfectly  smooth.  TTiis 
lallerdiuiiieteranii  mure  abrum 


GASOLINE  AUTOMOBILES  211 

idea  of  a  leak  can  be  dismissed,  but,  otherwise,  a  porous  pipe  can  be 
discovered  at  idling  speeds  by  squirting  gasoline,  upon  the  suspected 
surface  of  the  manifold  and  noting  if  the  motor  speeds  up.  If  it  does, 
this  is  a  sign  that  some  of  the  gasoline  has  been  drawfi  through  the 
holes  in  the  manifold,  enriching  the  mixture. 

The  leaks  around  joints,  connections,  or  gaskets  can  be  found  in 
much  the  same  way.  When  the  leak  is  found,  the  Joint  should  be 
tightened  if  possible,  or  a  new  gasket  should  be  put  in,  or  both.  In 
the  case  of  the  porous  manifold  casting,  it  can  be  painted  with  a  fairly 
heavy  paint  while  hot  so  that  the  pores  of  the  metal  are  well  opened. 
Then,  after  this  has  dried  in  thoroughly,  another  coat  will  probably 
finish  the  job.  If  this  does  not  prove  to  be  the  case,  special  cement 
for  filling  porous  castings  cau  be  purchased  and  applied;  or,  best 
at  all,  if  the  case  is  a  bad  one,  an  entirely  new  manifold  should 
be  put  in. 

FUEL  SUPPLY. 

For  storage  of  the  fiiel  required  for  the  propulsion  of  a  car  and  for 
feeding  the  fuel  to  the  carburetor,  many  different  systems  are  in  use. 

Tank  Placing.  In  automobiles,  the  gasoline  tanks  are  generally 
placed  under  the  front  or  rear  seats,  or  under  the  frame  at  the  rear. 
In  many  types  of  runabouts  and  roadsters,  the  tank  is  placed  above 
the  frame  at  the  rear. 

Fuel  Feeding.  When  .the  tank  is  at  the  rear,  or  when  it  is  under 
the  front  or  rear  seat,  no  special  provision  is  necessary,  under  ordinary 
circumstances,  to  insure  a  positive  flow  of  the  liquid  fuel  to  the 
carburetor^ 

Gravity.  With  the  tanks  placed  high,  the  gasoline  can  be 
depended  upon  to  run  down  to  the  float  chamber  by  gravity.  In 
mountainous  districts  it  is  sometimes  found,  in  climbing  very  steep 
hills,  that  the  angle  becomes  such  tha^  the  fuel  will  not  flow,  especially 
when  the  tanks  are  under  or  back  of  the  rear  seat,  or  when  they  are 
nearly  empty. 

A  means  of  getting  around  this  difficulty  is  to  place  an  auxiliary 
tank  of  one  or  two  gallons  capacity  on  the  front  of  the  dashboard, 
behind  the  engine  and  under  the  bonnet,  and  run  a  pipe  direct  from  it 
to  the  carburetor.  When  the  car  is  in  a  level  position,  this  auxiliary 
tank  fills  automatically  from  the  main  tank,  but  a  simple  vaVve  v^e- 


212 


GASOLINE  AUTOMOBILES 


by  more  positive  r 


vents  the  contents  of  the  auxiliary  tank  from  running  back  when  the 
machine  is  tilted  up.  In  thia  way  a  sufficient  supply  for  15  or  20 
miles  running  is  placed  in  a  j>osition  to  reach  the  carburetor  under 
any  possible  road  condition. 

Air  Prei^mtTe.  With  the  tanks  placed  low,  whether  under  the 
frame  or  above  it,  it  Is  necessarj'  to  feed  the  fuel  to  the  carburetor 
,ns  than  gravity.  One  of  the  commonest  sys- 
tems involves  pumping  a  low  air  pressure  into 
the  tank  above  the  fuel,  so  that  this  pressure 
forces  the  liquid  out  regardless  of  the  relative 
heights  of  tank  and  carburetor.  Ordinarily, 
a  small  hand  pump  is  sufficient  to  provide 
such  air  pressure,  though  in  modem  auto- 
mobiles equipped  with  cnmpreised-air  starting 
devices,  or  compressed-air  tanks  for  filling  the 
tires,  provisions  can  be  rea<lilj'  made  for  sup- 
j)lying  the  tanks  with  air  from  these  sources 
for  the  purpose  of  feeding  the  fuel. 

Exhaust    Prcsnure.    A    system    that    is 
much  used  for  providing  pressure  in  the  fuel 


GASOLINE  AUTOMOBILES 


213 


the  production  of  a  new  device,  which  is  called  the  Stewart  vacuum 
feed.  Thb  is  a  small  compact  circular  unit,  which  is  pUced  on  the 
dash  under  the  hood  for  use  with  a  rear  tank  and,  when  so  used, 
eliminates  the  pressure  feed.  A  sectional  drawing  of  this  is  shown  in 
Fig.  145.  It  may  be  described  as  follows:  There  are  three  connec- 
tions at  the  top,  one  to  the  gasoline 
tank,  one  to  the  intake  manifold, 
and  one  to  the  air  vent.  Through 
the  medium  of  the  intake-manifold 
connection,  the  motor  suction  is 
communicated  to  the  tank,  for 
that  is  what  the  device  amounts 
to.  This  produces  a  vacuum  and 
opens  the  valve  connecting  with 
the  gasoline  tank  That,  as  ueil 
as  the  connecting-pipe  line,  being 
air  tight,  gasoline  is  drawn  in  to 
fill  the  vacuum,  floning  mto  the 
upper  chamber  with  which  the 
gasoline  tank  communicatee) 

This  has  a  valve  connection 
to  the  lower  chamber,  operated  by 
means  of  a  float;  it  in  turn  is  con- 
trolled by  the  intake  manifold  suc- 
tion, through  the  medium  of  the 
system  of  levers.  Bv  it,  the  low  er 
chamber  Is  kept  filled  to  a  fairly 
high  level,  whence  feed  to  the 
carburetor  is  by  gravitj  This 
method  thus  does  away  with  all 
the  troubles  of  the  pressure  sj  li- 
tem, at  the  same  time  allowmg  of  ^  "' 
the  accessible  and  advantageous  '^"""""'s(^'„„.„,  .„„.„ 
rear  tank  location.    It  is  placed  as 

high  as  possible  on  the  inside  of  the  dash  under  the  hood,  hence  there 
is  never  any  trouble  with  the  'gravity  feed  even  on  the  steepest  hill. 
In  one  test,  this  vacuum-feed  device  increased  the  mileage  of  the  car 
per  gallon  of  fuel  by  more  than  22  per  cent. 


214 


GASOLINE  AUTOMOBILES 


Prfssiire-Operated  Feed  Deriee.  Carter  System.  Since  the 
THtrotluction  of  the  Stewart  device  described  above,  a  number  of 
(ievices  acting  on  somewliat  different  principles  have  been  brought 
out.  In  the  Carter  automatic  gravity  tank,  as  it  is  called,  the  suction 
and  compression  strokes  of  the  motor  are  used  to  furni-sh  the  pressure 
which  operates  a  .simple  diaphragm  pump,  first  in  one  direction,  then 
in  the  other,  Thi.s  diaphragm  pump  is  shown  at  the  right  of  Fig.  146 
and  is  marked  .1.  As  shown,  this  connects  through  a  ball  cheek 
valve  B  with  the  main  gasoline  tank,  the  strokes  of  the  diaphragm 
pump  drawing  fuel  mto  the  central  well  C,  which,  when  filled,  over- 


GASOUNE  AUTOMOBILES 


215 


It  is  advised  that  this  tank  be  connected  to  the  engine  in  any  con- 
venient place,  except  that  near  the  exhaust  manifold.  When  the  tank 
has  been  connected  and  is  ready  for  use,  prime  it  with  about  half  a 
pint  of  gasoline  poured  in  through  the  filler  cup  on  the  top.  After 
this  has  been  done,  the  tank  will  continue  to  operate  as  long  as 
there  is  fuel  in  the  rear  tank. 

Church  System.  In  the 
Church  system,  the  compres- 
sion, or  explosion  pressure,  is 
used  to  lift  the  fuel  through  the 
medium  of  the  specially  designed 
check  valve.  A  general  layout 
is  shown  in  Fig.  147,  in  which  it 
will  be  noted  that  the  check 
valve  is  mounted  in  the  rear 
cylinder  in  place  of  the  pet  cock. 
Through  this,  the  pressure  is 
maintained  in  the  main  tank  at 
the  rear  of  the  chassis,  thus 
forcing  gasoline  to  the  auxiliary 
tank.  Normally,  the  check 
valve  will  produce  about  one 
and  one-half  pounds  pressure  on 
the  main  tank,  but  the  arrange- 
ment of  the  system  is  such  that 
this  maximum  pressure  is  auto- 
matically increased  to  meet  the 
conditions  existing  at  any  time. 
In  this  sketch,  it  will  be  noted 
that  the  pressure  line  is  con- 
structed with  a  T,  one  part  of  *"™  "'  ^^'^  ^"^ 
the  pressure  going  to  the  auxiliary  tank  where  it  is  regulated  by 
means  of  a  fioat,  and  the  other  going  to  the  main  fuel  tank. 

By  referring  to  Fig.  148,  which  shows  a  section  through  the 
auxiliary  tank,  the  regulation  of  the  pressure  will  be  made  clear. 
When  the  supply  in  the  auxiliary  tank  gets  low,  the  float  /* drops  down ; 
this  moves  the  rod  S  down  also.  The  downward  movement  of  the 
rod  forces  down  the  valve  R,  which  prevents  the  air  escaping  through 


216  GASOLINE  AUTOMOBILES 

the  condensing  tube,  and  thus  the  entire  pressure  in  the  sj'stem  is 
exerted  upon  the  main  tank  with  the  result  that  the  pressure  rises 
there.  WTien  more  fuel  is  forced  to  the  auxiliary  tank,  the  float  rises 
and  allows  the  air  relief  valve  R  to  rise;  this  opens  the  passage  to  the 
condensing  tube  again,  so  that  tlie  air  can  escape  in  that  way  and 
relieve  the  pressure  upon  the  main  tank.  In  this  way,  a  balancing 
effect  is  produced,  which  automatically  keeps  the  auxiliary  tank  well 
supplied. 

From  this  tank  the  fuel  flows  by  gravity  to  the  carburetor. 
There  is,  however,  an  additional  and  valuable  feature  of  this  system. 
On  top  of  the  tank  will  be  found  a  vapor  outlet  0,  and  in  the  sketch 
it  will  be  noted  that  this  is  connected  back  to  the  carburetor.  In  this 
way  any  vap(}rizatioii  which  occurs  jn  the  auxiliary  tank  is  utilized. 
This  has  the  double  advantage  of  being  a  source  of  economy  and  of 
keeping  the  system  closed  against  the  entrance  of  dust.  Provision  ia 
made,  despite  this,  for  cleansing  out  sediment,  by  a  drain  plug  at  the 
bottom  of  the  tank.  The  gasoline  check  valve  will  be  noted  at  the 
top,  this  operates  in  conjunction  with  the  float  stem  and  air-relief 
valve,  that  is,  the  rising  of  the  float  in  a  full  tank  will  automatically 
cut  ofT  further  supply  by  means  of  the  check  valve,  as  well  as  by  open- 
ing the  air-relief  valve  at  the  bottom.     Similarly,  the  downward 


GASOLINE  AUTOMOBILES  217 

As  a  further  safeguard  against  breakage,  and  to  aUow  alterations 
in  the  relative  positions  of  different  parts,  due  either  to  the  straining 
of  the  machine  while  it  is  in  use  or  to  a  change  of  adjustments  when 
it  is  disassembled  or  reassembled,  loops  or  coils  introduced  at  proper 
points  in  a  pipe  line  are  of  great  advantage. 

Stop  cocks  close  to  the  tanks  are  an  excellent  safeguard  against 
fire,  since  they  permit  the  shutting  off  of  the  fuel  supply  in  the  case  of 
any  breaks  in  the  line.     Such  safeguards  should  always  be  provided. 

With  reference  to  the  pressure  system  of  fuel  feed,  there  is  hardly 
any  limit  to  the  precautions  which  must  be  taken  to  avoid  leaks.  The 
smallest  leak  puts  the  system  out  of  commission  as  soon  as  the  pressure' 
leaks  down  to  a  point  where  the  fuel  will  not  rise  to  the  carburetor. 
When  this  occurs,  the  engine  cannot  be  operated  until  the  leak  is 
found  and  fixed.  To  avoid  leaks,  many  drivers  go  over  all  joints 
frequently  and  likewise  replace  all  old  packing.  In  addition,  they 
wipe  the  joints  with  soap  to  prevent  leakage  and  then  cover  them  on 
the  outside  with  tire  tape  or  similar  flexible  material  which  can  be 
wound  on  in  such  a  way  as  to  stay  permanently.  The  rapid  adoption 
of  the  Stewart  device,  since  it  was  brought  out  in  1914,  shows  better 
than  anj'thing  else  how  troublesome  was  the  pressure-feed  system. 
Statistics  for  1914  cars  showed  that  in  237  different  models,  109  had 
the  gravity  tank  under  the  seat,  and  31  in  the  cowl,  this  making  140 
with  gravity  feed,  leaving  97  with  the  rear-pressure  tank  location. 
Similar  statistics  for  1915  show  52  per  cent  in  favor  of  the  rear  tank 
location,  while  1916  shows  almost  66  per  cent  with  rear  location,  and 
:34  per  cent  vacuum  fed. 

Res«Te  Tanks.  To  guard  against  the  annoying  mishap  of 
having  the  gasoline  give  out  while  an  automobile  is  in  use,  perhaps 
remote  from  any  source  of  supply,  many  cars  are  now  provided  with 
reserve  tanks  which  bold  back  one  or  two  gallons  of  gasoline.  This 
reserve  cannot  be  used  except  when  it  is  fed  into  the  system  through 
the  deliberate  intent  of  the  operator. 

In  its  simplest  and  one  of  its  best  forms,  a  reserve  tank  takes 
the  shape  of  a  partitioned-off  portion  of  the  main  tank,  into  which 
the  gasoline  automatically  flows  through  an  opening  at  the  top  when 
the  tank  is  filled.  It  cannot  pass  to  the  carburetor  until  a  special 
valve  in  the  bottom  is  opened  and  the  fuel  allowed  to  flow  back  into 
the  mun  tank. 


218  GASOLINE  AUTOMOBILES 

A  later  and  even  moru  simple  provision  is  the  use  for  the  gasoline 
tank  of  A  three-way  outlet  cock  which  has  a  fairly  long  extension  up 
into  the  tank.  The  extension  tube  is  open  at  the  top  and  has  a  hole 
near  tiie  bottom  of  the  tank  which  communicates  through  a  branch 
tube  with  the  third  way  of  tlie  cock.  When  the  outlet  cock  is  set  for 
iiiirmal  flow,  the  fuel  feeds  until  the  level  reaches  the  top  of  the  exten- 
sion; at  that  point  it  stops  flowing.  This  is  the  warning  to  the  driver 
tlmt  his  fuel  is  low.  Then  all  he  has  to  do  is  to  turn  the  outlet  cock 
to  tlie  other  pojition,  thus  allowing  the  fuel  to  feed  from  the  bottom 
liole  of  the  extension  tube.  The  remainder  of  the  fuel,  that  is,  the 
amount  represented  bj'  the  difference  in  level  between  the  top  and 
bottom  of  the  extension  tube,  will  carry  the  car  to  the  next  fuel  station. 

Fuel  Gages.  The  development  of  depth  and  quantity  indicators 
has  received  much  attention  in  the  last  few  years,  with  the  result  that 
practically  all  new  cars  have  some  form  of  gage  on,  or  In,  the  fuel 
system.  On  rear-pressure  tanks,  it  is  usually  located  on  the  tank,  so 
the  driver  must  go  to  the  rear  of  the  car  to  see  how  much  fuel  he  has 
left,  but  on  cowl  tanks  or  those  located  under  the  seat,  it  is  possible 
to  ha\e  the  gage  set  on  the  instrument  board  or  the  dash,  as  tlie  case 
may  be,  so  that  it  is  in  plain  sight.  Practically  all  the  gages  give 
indications  in  gallons  and  fractions,  so  that  with  the  gasoline  gage  and 


GASOLINE  AUTOMOBILES  219 

the  fuel  has  gradually  collected  until  there  was  enough  to  cut  off 
the  flow.  A  good  way  out  of  such  a  difficulty  is  to  close  connections 
at  the  tank  and  at  the  carburetor,  take  the  entire  fuel  line  off  and 
blow  it  out  with  compressed  air.    This  will  clean  it  thoroughly. 

Lock  on  Fuel  Line.  The  garage  or  repair  man  can  insert  a  very 
efficient  lock  on  any  car  by  putting  into  the  fuel  line  at  a  convenient 
point  a  shut-off  cock  which  works  with  a  removable  key.  These  are 
readily  obtained,  and  any  good  workman  can  install  one  in  a  couple 
of  hours.  Many  owners  of  cars  would  be  glad  of  an  effident  lock 
and  would  be  willing  to  pay  well  for  on&.  This  one  has  the  advanta^ 
of  being  simple,  cheap,  and  effective. 

SUMMARY  OF  CARBURETOR  INSTRUCTIONS 

Q.    What  is  a  carburetor? 

A.  A  carburetor  is  a  device  for  vaporizing  liquid  fuels,  and  for 
adding  to  them,  when  vaporized,  the  proper  amount  of  air  for  imme- 
diate and  complete  combustion. 

Q.    How  many  types  of  carburetors  are  there? 

A.  Three:  the  surface  form,  now  out  of  date;  the  filtering  type, 
no  longer  used,  except  on  one  or  two  English  cars;  and  the  spraying 
tvpe,  to  which  all  modern  devices  belong.  The  first  was  useful  only 
with  the  very  light  and  extremely  volatile  fuels  of  ten  and  twenty 
jears  ago. 

Q.    What  are  the  essential  units  of  a  spraying  type  of  carburetor? 

A.  The  essential  parts  of  a  spraying  type  of  carburetor  are: 
a  float  chamber  with  a  float  arranged  to  regulate  the  level  of  the 
inflowing  fuel;  a  needle  and  nozzle,  or  spraying  device,  which  should 
preferably  be  adjustable;  an  air  opening,  which  may  be  variable  or 
not,  which  may  be  in  multiple  form  or  not,  which  may  have  automatic 
valves  to  regulate  its  size  or  not;  and  a  throttle  valve  to  control  the 
quantity  of  mixture  passed  into  the  cylinders.  As  an  important 
auxiliary,  the  needle,  nozzle,  or-  spraying  device,  whatever  its  form, 
should  be  placed  in  a  special  vaporizing  chamber,  of  a  size  and  shape 
to  give  the  best  results. 

Q.    Do  all  these  appear  in  all  modem  carburetors? 

A.  Practically  all,  in  one  form  or  another,  and  also  a  consider- 
able number  of  additional  parts.  Thus  many  carburetors  have  two 
or  more  nozzles, or  spraying  devices;quite  afew  have  two  air  ov^tv\u^. 


$ag  GASOLINE   AUTOMOBILES 

one  of  which  is  controlled  by  an  automatic  valve,  some  have  three  air 
openin{!s;  many,  in  fact  most,  of  the  modern  devices  have  a  method 
of  heating  tiie  vaporizing  chamber,  or  the  space  immediately  above  or  \ 
below  it,  so  as  to  facilitate  complete  vaporization,  as  well  as  to  quicken 
the  action;  some  have  air  valves  in  the  form  of  steel  balls;  others  ' 
have  pistons  and  dash  pots  to  eliminate  sudden  movements  or  changes 
in  operation;  many  have  auxiliary  devices  intended  to  give  a  special 
starting  mixture;  practically  all  have  removable  strainers  for  cleaning 
the  fuel,  some  having  two  different  forms  of  strainer. 

Q.  What  is  the  generally  accepted  form  of  needle  valve,  or 
spraying  nozzle? 

A.  There  is  no  one  accepted  form,  although  the  majority  of 
carburetors  have  spraying  nozzles,  or  needle  valves,  which  come  into 
.one  of  four  classifications.  These  are:  the  hollow  nozzle  with  an 
opening  at  the  top,  slightly  smaller  in  inside  diameter  than  in  outside, 
so  that  the  spray  of  fuel  is  opened  out  in  a  fan-like  form ;  the  same  form 
with  an  internal  needle  having  a  long  tapered  point  and  screwing  up 
into  it  from  below,  this  giving  a  means  of  adjustment  which  the  plain 
hole  does  not;  the  same  plain  tube  and  hole,  with  an  external  needle 
having  a  tapered  point  and  screwing  down  into  it  from  above  (in 
this,  the  body  of  the  Jieedle  divides  the  spray  of  fuel);  and  the  form 


GASOUNE  AUTOMOBILES  221 

Q.    How  does  the  auxiliary  air  valve  remedy  this? 

A.  By  adding  air  when  the  motor  suction  gets  strong  enough  to 
open  the  auxiliary  air  valve,  the  amount  added  being  in  direct  propor- 
tion to  the  strength  of  the  suction. 

Q.  What  other  disadvantage  Is  there  in  over  rich  mixtures  for 
h^  speeds? 

A.  An  over  rich  mixture  at  high  speeds  shows  a  noticeable  lack 
of  economy,  as  at  these  speeds  a  great  amount  of  gas  is  being  used, 
and,  if  too  rich,  the  gasoline  fuel  is  being  used  up  very  rapidly.  The 
makers  of  practically  any  carburetor  equipped  with  an  auxiliary  air 
valve  will  guarantee  a  saving  of  20  per  cent  in  fuel  consumption  when 
it  replaces  a  carburetor  which  has  no  auxiliary  air  valve. 

Q.    Why  are  some  carburetors  water-jacketed? 

A.  The  conversion  of  a  liquid  like  gasoline  into  a  vapor  is  a 
chonical  action  which  needs  heat  to  complete  it.  If  no  heat  is  sup- 
plied, it  will  be  taken  from  surrounding  objects,  or  else  the  vaporiza- 
tion will  not  be  completed.  This  abstraction  of  heat  from  the  sur- 
roundings can  be  noticed  in  unjacketed  carburetors  in  the  form  of  frost 
or  snow  forming  on  the  outside  of  the  vaporizing  chamber.  The 
water-jacketed  carburetor  has  the  hot  water  of  the  engine  system 
circulated  through  it  to  supply  the  needed  heat,  and  thus  assist  and 
complete  the  vaporizing  of  the  fuel. 

Q.    Why  are  some  carburetors  supplied  with  hot  air? 

A.  This  is  done  for  the  same  reason.  The  pre-heated  air  is 
supplied  to  vaporize  the  fuel,  instead  of  using  cold  air  and  supplying 
heat  from  other  sources.  In  principle,  it  is  practically  the  same  as 
the  other. 

Q.    When  hot  air  is  supplied,  how  is  this  heated? 

A.  Generally  a  stovJe,  or  a  hollow  member  around  the  heated 
exhaust  pipe,  is  connected  by  metal  tubing  to  the  air  inlet  of  the  car- 
buretor; in  this  way  all  of  the  air  drawn  in  is  forced  to  pass  around  the 
exhaust  pipe,  which  beats  it.  This  is  not  always  the  case,  some 
makers  using  air  sucked  in  from  around  the  heated  cylinders.  Still 
others  use  an  exhaust  jacket  on  the  carburetor,  and  draw  the  cold 
air  supply  in  around  this,  so  that  it  is  heated. 

Q.    What  difference  does  the  fuel  make  in  this  heating  method? 

A.  On  the  heavier  fuels,  such  as  kerosene,  alcohol,  distillate,  and 
mixtures  of  these  with  gasoline,  a  great  quantity  of  beat  is  necseasjU^ , 


222  GASOLINE  AUTOMOBILES 

as  these  heavier  fuels  are  more  difficult  to  vaporize  and  are  also  slower 
to  start  vaporizing.  This  means  an  extra  supply  of  heat  at  starting 
time,  and  more  than  the  usual  supply  at  all  times.  It  works  out,  in 
the  direct  use  of  e."diaust  gases,  through  a.  small  pipe  tapped  Into  the 
exhaust  manifold,  thus  giving  the  highest  available  teoiperature. 
This  is  used  through  the  carburetor  jackets,  but,  in  addition,  the  air 
supply  to  vaporize  the  fuel  is  heated.  Another  vaporizer  of  heavy 
fuels,  which  has  been  quite  successful,  places  heavy  metal  weights 
inside  the  carburetor  in  the  upper  part  of  the  vaporizing  chamber  and 
then  forces  the  exhaust  gases  through  hollow  passages  in  these.  In 
this  way,  the  weights  are  heated  up,  and  this  heat  is  transmitted  to 
the  gas  and  air;  the  size  and  nature  of  the  metal  gives  an  equnble 
supply  of  heat,  regardless  of  the  exhaust  gases. 

Q.     What  is  the  throttle  valve? 

A.  A  valve  placed  in  the  pipe  between  carburetor  and  cylinders 
to  vary  (or  throttle)  the  quantity  of  mixture  flowing  to  the  latter.  This 
is  generall\'  connected  to  the  throttle  lever  on  the  steering  wheel,  and 
to  the  accelerator  pedal.  General  practice  in  driving,  after  the  initial 
stages  of  learning,  is  to  set  the  hand  throttle  at  some  medium  point, 
and  thereafter  to  var\-  the  speed  of  the  motor  bj'  means  of  the  foot. 
What  is  the  general  form  of  this  throttle  valve? 


GASOLINE  AUTOMOBILES  223 

Q.    WhatUaVcDturitube? 

A.  This  is  the  essential  principle  of  the  inner  member  of  the 
Venturi  meter,  invented  for  measuring  the  flow  of  water.  It  consists 
of  two  cone-shaped  tubes  diverging  in  opposite  directions,  with  the 
proper  relation  of  angles  to  one  another  and  to  the  diameter  of  the 
smallest  point,  or  meeting  point,  of  the  two  tubes.  The  larger  angle 
should  be  at  the  bottom,  or  entering  end  for  the  gases;  the  nozzle, 
or  needle,  should  be  just  at  or  just  below  the  smallest  diameter;  and 
the  gases  should  flow  through  from  end  to  end,  that  is,  air  in  at  one 
end,  gas  in  at  the  middle,  mixture  out  at  the  other  end.  In  the  true 
Venturi  tube,  the  bottom  angle  is  30  degrees,  the  top  angle  5  degrees. 

Q.    When  more  than  one  nozzle  is  used,  how  are  they  connected? 

A.  In  practically  all  multiple-nozzle  forms,  the  arrangement  is 
such  that  the  second  (and  later)  nozzles  are  brought  into  action  by 
increased  demand  from  the  engine,  that  is,  automatically.  In  one 
case,  a  flap  valve  covers  the  second  nozzle;  but,  as  the  suction  increases 
this  is  drawn  up  and  the  nozzle  is  uncovered;  having  its  own  air 
supply,  the  nozzle  begins  to  function  as  soon  as  it  is  uncovered,  the 
amount  of  gas  supplied  by  it  depending  upon  the  extent  to  which  it  is 
uncovered  by  the  suction.  In  another,  the  first  nozzle  passes  a  fixed 
amount  of  fuel,  as  the  engine  demands  rise;  this  suction  is  communi- 
cated to  the  second  nozzle  and  the  fuel  standpipe  from  which  it  draws; 
it  is  put  into  action,  but  varies  its  supply  always  according  to  demand. 
The  combination  of  fixed  and  variable  nozzles  gives  reasonably 
good  vaporization  at  all  possible  speeds  and  under  all  variations  of 
conditions. 

Q.    What  Is  a  horizontal-outlet  carburetor? 

A.  The  first  carburetors  were  all  connected  to  the  engine  cylin- 
ders through  the  intermediary  of  an  inlet  manifold.  The  latter  con- 
nected up  to  the  cylinder  horizontal  face  at  a  number  of  points,  and 
was  carried  down  to  a  single  flange  for  the  carburetor  connection. 
While  the  surface  of  this  flange  was  horizontal,  the  outlet  on  the  car- 
buretor, that  is,  the  passage  to  this,  was  vertical.  Consequently, 
carburetors  made  to  fit  this  arrangement  are  said  to  have  vertical 
outlets.  With  the  principle  of  block  casting,  it  is  usual  to  incorporate 
the  inlet  manifold  in  the  cylinder  casting  and  have  a  single  carburetor 
opening  and  place  for  attaching,  this  being  a  vertical  face.  As  the 
face,  or  carburetor  flange,  is  at  right  angles  to  the  body  o{  live  cmW- 


224  GASOLINE  AUTOMOBILES 

retor  outlets,  this  brought  about  a  horizontal  outlet.  A  carburetor 
with  this  form  of  outlet,  and  intended  to  bolt  directly  upon  the  cylin- 
der casting  in  the  manner  just  described,  is  called  a  horizontal- 
outlet  carburetor  or  a  horizontal  carburetor. 

Q.     What  is  a  double  carburetor? 

A.  A  double  carburetor  is  one  made  for  a  V-type  of  motor  in 
which  a  common  float  chamber  supplies  fuel  to  two  separate  and 
distinct  groups  of  vaporizing  chamber,  fuel  nozzle  and  needle,  air 
inlet,  etc.,  each  half  supplying  one  of  the  blocks  of  cylinders.  That 
is  to  saj-,  it  is  a  double  carburetor,  or  two  carburetors,  if  that  Is  easier 
to  imdcrstaiu],  each  one  of  which  supplies  one-half  of  the  engine's 
cylinders,  but  has  jiothing  to  do  with  the  other  half.  It  has  been 
foimd  that  better  results  can  be  obtained  in  this  way  than  in  any  other. 

Q.    What  has  been  the  effect  of  vacuum  feeds? 

.\.  The  principal  effect  has  been  to  raise  the  carburetor.  For- 
merly, the  ciirburetor  had  to  be  set  low  so  the  fuel  could  flow  to  it,  and 
e\en  when  pressure  became  general,  the  carburetors  were  still  set  very- 
low.  Now,  with  auxiliary  tank  feeding,  it  is  possible  to  raise  the 
carburetor  from  twti  to  six  inches,  and  practically  all  designers  have 
taken  advantaf,'e  of  this.     It  makes  the  carburetor  easier  to  adjust, 


GASOLINE  AUTOMOBILES.  225 

el  would  flow  to  it  on  the  steepest  hill.  The  substitute  for  this  was 
essure,  but  this  necessitated  much  apparatus,  and  the  system  had  to 
■■  kept  air  tight,  or  it  was  useless.  In  this  form  an  air  pump  forced 
r  through  a  regulator  into  the  air-tight  tank,  this  pressure  forcing 
e  fuel  out  and  to  the  carburetor.  The  latest  device  is  similar  to  the 
£uum  tank  but  is  operated  by  utilizing  the  pressure  of  tlie  exhaust, 
>rking  through  a  pressure-regulating  valve. 

Q.    Describe  this  exhaust-operated  system? 

A.  The  exhaust  gas  pressure  is  cut  down  to  a  few  pounds  by  the 
gulator,  and  goes  thence  into  the  rear  gasoline  tank.  Here  it 
sates  pressure  and  forces  out  gasoline  which  must  flow  to  the  auxil- 
ry  tank.  As  the  tank  fills,  a  float  rises,  and  with  it  a  needle,  which 
)se3  a  connection  to  the  outside.  When  the  tank  is  filled  to  the 
edetermined  level,  this  arrangement  opens  the  outside  connection, 
jd  the  exhaust  gas  is  free  to  escape.  As  the  fuel  flows  to  the  carbu- 
tor,  tiie  float  drops  and,  in  time,  closes  this  opening,  when  the 
haust  pressure  starts  the  fuel  flowing  again.  So  the  arrangement 
float  and  outside  opening  keeps  the  auxiliary  tank  continually  filled. 

Q.  When  no  fuel  flows,  yet  the  tank  is  filled,  what  Is  the 
Mible? 

A.  If  the  tank  is  full  and  no  fuel  flows,  there  must  be  an  obstruc- 
>n  in  the  line  somewhere.  Try  the  gasoline  pipe  line  first  for  a  bend 
kink.  If  none  is  found,  try  the  carburetor  connection.  Failing 
at,  remove  the  strainer  and  in.spect  it.  Then  look  into  the  float  and 
■at  chamber,  float  valve  and  outlet  to  vaporizing  chamber.  Some 
le  of  these  is  sure  to  be  at  fault. 

Q.    How  can  a  punctured  float  be  managed,  so  as  to  get  home? 

A.  Let  the  float  sink,  but  oppose  this  sinking  by  means  of  a 
ring,  cai»f  uUy  cut  to  the  right  length  to  give  the  same  effect  as  if  the 
lat  were  O.  K.  This  will  carry  the  carto  the  nearest  repair  shop,  or 
eking  that,  will  take  it  home.  A  punctured  metal  float  can  readily 
:  soldered,  but  should  be  dried  out  very  carefully  first,  this  being  done 
imanly  to  make  sure  there  is  no  more  gasoline  inside,  nor  any  vapor 
condense. 

Study  Questions  for  Home  Work 

1.  Describe  the  construction  and  operation  of  the  Stromberg 
odel  "H". 

2.  Tell  bow  the  main  jet  is  replaced  on  the  Zenith. 


Sm  GASOLINE  AUTOMOBILES 

3.  Give  tlie  method  of  making  a.  slow-speed  adjustment  on  the 
Ford  I'Jir. 

4.  How    many    adjustments    has   the   Brovme   carburetor? 
Describe  them. 

5.  Describe  the  construction  of  the  Master  carburetor  throttle, 
(i.     How  doca  the  Lfinguemare  differ  from  other  carburetors? 

7.  Mention  in  detail  the  process  of  starting  adjustment  of 
the  Webber. 

8.  How  many  adjustments  has  the  Ra^-field?     Describe  them. 

9.  Tell  in  detail  the  principle  upon  which  the  Bail  and  Ball 
carburetor  works. 

10.  What  is  the  mixture-indicating  pointer  on  the  Newcomb? 
What  are  its  advantages? 

11.  How  would  you  adjust  a  new  Schebler  Model  "L"? 

12.  What   is  the  pre<]ominating  feature  of  the  Stewart  car- 
buretor? 

13.  How  in  the  Johnson  carburetor  adjusted? 

14.  What  are  the  salient  features  of  the  Packard  carburetor? 

15.  Describe  tlie  adjustment  of  the  Cadillac,  (aj  low  speed, 
(b)  starting,  (c)  high  speed. 

16.  Select  and  describe  the  working  of  a  heavy  fuel  carburetor. 


GASOLINE  AUTOMOBILES 


ENQINE-QROUP   ELEMENTS   (Continued) 
VALVES  AND  THEIR  MECHANISM 

Importance  of  Valves.  Probably  the  most  important  thing 
about  a  four-cycle  gasoline  engine  is  the  valve,  or,  more  correctly,  are 
the  valves,  for  the  usual  number  is  two  per  cylinder.  The  opening 
and  closing  of  these  control  the  functions  of  the  engine ;  for  if  the  valve 
does  not  open  and  allow  a  charge  of  gas  to  enter,  how  can  the  piston 
compress,  and  the  ignition  system  fire,  a  charge?  Similarly,  if  the 
exhaust  valve  is  pot  opened  and  the  burned  ^ases  allowed  to  escape, 
they  will  mingle  with  and  dilute  the  fresh,  incoming  charge,  possibly  to 
the  extent  of  making  the  latter  into  a  non-combustible  gas.  This 
is  purposely  stated  in  this  way  because  both  methods  mentioned 
have  been  utilized  for  governing  the  engine  speed,  although  not  to 
any  great  extent  in  automobile  work. 

Summary  of  Valve  Features.  In  the  valves  and  valve  mech- 
anisms of  modern  gasoline  engines  there  have  been  and  are  impending 
more  interesting  changes  than  seem  in  prospect  in  any  other  portion  of 
the  mechanism  of  the  modern  automobile.  Particularly  is  this  the 
case  with  reference  to  the  present  tendency  to  discard  the  poppet 
valve  with  its  many  objectionable  features.  Even  where  there  is  no 
tendency  toward  the  use  of  a  sleeve-valve  or  slide-valve  form  of 
motor,  much  experimenting  has  been  done  with  increasing  the  number 
and  changing  the  position  of  the  valves. 

Poppet  Valixa.  Though  the  very  first  internal-combustion 
engines  ever  made  were  operated  with  slide  valves,  the  poppet  valve 
was  introduced  very  early  in  the  history  of  this  art,  and  has  reigned 
supreme  in  practically  all  types  of  gas  and  gasoline  engines. 

The  chief  advantage  of  the  poppet  valve  is  its  capacity  for  con- 
tinuous operation  at  excessively  high  temperatures,  but  since  the 
cooling  of  engines  baa  progressed  to  the  status  of  MgU  Te\\«?Q%X.'^ , 


228  GASOLINE  AUTOMOBILES 

this  advantage  is  of  less  importance  than  formerly.  And  the  dis- 
advantages of  poppet  vah'es — the  small  openings  that  they  afford, 
the  noisy  and  hammering  action  they  involve,  their  tendency  to  leak 
and  in  other  ways  give  out,  and  the  necessity  for  frequently  regrinding 
them— are  objections  so  serious  that  it  is  no  wonder  the  prospect  of 
their  elimination  is  so  widely  welcomed.  J 

About  the  only  recent  improvement  that  has  been  made  in  1 
poppet  valves  is  in  the  quality  of  material  used  in  them.  Many  1 
valves  now  used  have  cast-iron  and  nickel  heads,  which  offer  a  max- 
imum resistance  to  warping  from  the  heat  to  which  they  are  subjected. 
These  are  fitted  with  carbon-ateel  stems,  which  are  superior  in  their 
wearing  (|ualities.  More  use  has  been  made  recently  of  tungsten 
as  a  material  for  valves.  Steel  containing  this  is  even  harder  than 
nickel  steel,  and  experiments  have  shown  that  it  does  not  warp  as 
much.  In  practice,  the  objection  found  to  cast-iron  heads  was  thai 
the  fastenings  to  the  carbon-steel  stem  were  not  sufficiently  strong 
to  withstand  the  constant  pulling  and  pushing  to  which  a  valve  was 
subjected.     As  a  result  the;'  separated,  causing  trouble. 

In  the  operation  of  poppet  valves,  the  cams  become  an  important 
factor.     These  are  the  parts  which,  in  revolving,  raise  the  valves  so 


•     GASOLINE  AUTOMOBILES  229 

cylinder  engines  which  have  the  cylinders  cast  in  threes,  instead  of  in 
a  block,  as  the  one  referred  to.  On  some  motors  where  this  construc- 
tion has  not  found  favor,  the  designers  have  followed  the  plan  of 
enclosing  the  individual  valve  mechanisms.  While  more  expensive, 
this  method  is  equally  as  efficient.  On  the  other  hand,  it  adds  to  the 
parts,  and  the  whole  modern  tendency  has  been  to  reduce  the  number 
of  parts. 

Sleeve  Valves.  This  type  of  valve,  while  not  at  all  new,  has  only 
within  the  past  few  years  come  into  considerable  prominence,  chiefly 
as  a  result  of  the  truly  remarkable  performances  of  the  Knight  motor, 
which  is  equipped  with  the  most  advanced  examples  of  this  type 
of  valve. 

Contrary  to  past  opinion,  it  has  been  conclusively  demonstrated 
that  sleeve  valves  do  not,  to  any  perceptible  degree,  increase  the 
tendency  of  a  motor  to  overheat,  nor  do  they  wear  at  any  very  meas- 
urable rate.  They  afford,  moreover,  in  the  best  constructions,  a  much 
higher  thermal  and  mechanical  efficiency  than  it  is  possible  to  secure 
from  the  average  poppet-valve  motor,  this  improvement  being  due  to 
the  better-shaped  combustion  chamber  that  can  be  used  and  the 
greater  areas  of  valve  opening,  which  facilitate  the  ingress  and  egress 
of  the  charges. 

Another  advantage  in  favor  of  the  sleeve  valve  is  that  its  timing 
is  permanent  and  unchangeable  and  does  not  alter  materially  with 
wear.  Not  the  least  of  the  merits  of  the  sleeve  valve  is  found  in 
the  fact  that  it  lends  itself  to  positive  operation  by  eccentric  mech- 
anisms, which  are  in  every  way  greatly  superior  to  the  non-positive 
cam  mechanisms  universally  used  to  actuate  poppet  valves. 

A  very  good  example  of  this  latest  type  of  Knight  motor  is 
illustrated  in  Fig.  149,  showing  the  intake  side  of  the  Moline-Knight 
four-cylinde^  motor. 

Sliding  Valves.  Sliding  valves  of  other  than  the  sleeve  type, 
embracing  a  considerable  variety  of  piston  valves  and  valves  similar  to 
those  employed  in  steam  engines,  have  not  found  as  much  favolr  with 
designers  of  automobile  engines  as  have  other  types  herein  referred  to. 

One  exception  is  the  successful  use  of  a  "split-ring''  valve  sliding 
up  and  down  in  the  cylinder  head  just  above  the  piston,  which  has 
found  successful  application  in  a  few  motors  recently  built  by  the 
Renault  Company,  of  France. 


GASOLINE  AUTOMOBILES 


Rotating  f  'aires.  A  number  of  engines  witli  n)tating  valves  lia^'e 
!>een  built  from  time  to  time,  but  none  of  these  seem  to  have  survived 
the  test  of  time,  for  not  one  which  was  in  evidence  two  years  ago  ia 
being  made  now.  A  case  in  point  is  the  Speedwell  car  with  the  Mead 
rotating- valve  motor.     Tlie  motor  was  excellent  but  is  no  longer  made. 

Half-Time  Shafts.  For  the  actuation  of  the  valve  meclianiam 
of  any  four-cycle  motor,  it  is  necessary  to  have  a  shaft  (or  in  the  case 


GASOLINK  AUTOMOBILES 


231 


The  most  impurtant  recent  innovatinii  in  this  detail  of  autn- 
inobtle  mechanism  is  the  driving  of  Iialf-tiine  shafts  by  silent  chains 
in  place  iif  the  lon]i;-nse<l  gearing;  of  spur  anrl  Iielical  type.  By  this 
improvement  the  noise  of  the  fjears  is  eliminat<.'<l. 

A  tj-pical  silent-chain  installation,  driving  half-times  haft  and 
other  shafts  as  well,  is  .seen  in  Fig.  ir>0,  which  presents  the  King  eight- 


cylinder  motor  witJi  the  chain  cover  rcmiived.  Tliese  occupy  the 
compartment  formerly  called  the  gear  case,  or  gear  cover,  when  all 
driving  was  done  by  gears.  Here  it  «ill  l>e  noted  that  there  are  twr) 
sprfjckcta  on  the  crankshaft;  one  driving  the  camshaft  thn)Ugh  the 
medium  of  a  third  sprocket  whidi  servos  a  doulile  pur(Kisc,  as  a  tWm 


232  GASOLINE  AUTOMOBILES 

tightener  and  as  a  drive  for  the  pressure  oil  pump;  while  the  other 
sprocket,  through  a  second  silent  chain,  drives  the  electric  generator 
at  the  right,  no  tightener  being  needed  as  the  generator  can  be 
moved  sufficiently  to  care  for  this. 

In  the  Cadillac  motor,  shown  in  Fig.  2,  Part  I,  a  pair  of  gears  is 
used,  one  driving  the  camsliaft  from  the  crankshaft,  while  the  other 
drives  the  auxiliary  shaft  from  the  camshaft.  In  the  American  form 
of  Knight  sliding  sleeve-valve  motors,  shown  in  Fig,  149,  a  pair  of 
silent  chains  is  used  for  the  eccentric  shaft  on  one  side  and  the  electric 
generator  on  the  other.  These  are  driven  from  a  pair  of  sprockets 
set  side  by  side  on  an  extension  of  the  crankshaft. 

A  point  that  should  be  brought  out  in  connection  with  silent- 
chain  camshaft  driving  is  that  the  use  of  the  chain  allows  the  siiafts 
to  be  placed  anywhere  desired  and  thus,  to  a  certain  extent,  frees  ■ 
the  designer  from  the  former  restriction  of  a  two-to-one  reduction  I 
ratio  in  the  gears,  which  rather  fixwl  the  size  and,  consequently,  thft'' 
position  of  the  gears.  This  restriction  had  an  influence  also  u])on 
cylinder  design,  as  the  center  of  the  camshaft  fixed  the  center  of  all  the 
valves,  that  is,  their  distance  from  the  center  line  of  the  motor. 

DETAILS  OF  POPPET-VALVE  QEARS 


GASOLINE  AUTOMOBILES 


TABLE  I  • 
TItnInx  Resulation  of  a  Number  of  Prominent  French  Motors 


'S3-' 


,  1908. 

^  h.p..  4  cylmden. . . 
10/14  b.p.,  4  cylinder, 


ColtiD-Dei»«outt«— 18/22  h,p, .  . 
Broubot — 12   h.p.,   4   try  linden. 

T5/110  


PeufCDt  (Bta^itti). . 
■—    OVp.  ■"""■ 


Parmt— 1*  fa.p.,  80/100  

Dimusj— 10/12  h.p.,  100/120. 
Vinol-Degi^ilBnd  —  i'2/lOb.p.. 


SulWn— Q/12   b.p.,  4  ej'lindua, 

75/110 

HtMult— 8  b.p..  2  cyliade™. .  .  . 
Umc— 20h.p,.  7S/110 


n  ATrmiiced  ia  Cbe  order  of  Ibeir  in 


II  ipeedi.      Tba  anclu 


be  advuiced  at  nUicdad  b] 


hJ  by  tba  drir«r. 

In  laying  out  or  designing  a  set  of  cams  for  a  gasoline  engine, 
such  as  is  used  on  an  automobile,  it  is  first  necessary  to  decide  upon 
the  exact  cycle  upon  which  to  operate  the  engine.  By  this  is  meant 
the  exact  length  of  time,  as  referred  to  the  stroke,  in  which  the  valve 
action  will  take  place.  Upon  this  subject,  designers  all  over  the 
world  differ,  and  no  wonder,  as  this  cycle  can  but  be  judged  by 
results,  for  it  is  impossible  to  watch  it  as  it  transpires.  Deductions 
differ,  therefore,  as  to  what  happens  and,  consequently,  as  to  the 
effect  of  various  angles  of  banning  and  ending  of  the  \a.We  w^cjt^. 


''      iSM                      GASOLINE  AUTOMOBILES 

TABLE  II 

TiminE  ResuUtlon  on  a  Number  of  Prominent  American  Motors 

No. 

U?' 

■a„"' 

Lndot 

Op.Dto, 

Cl«m. 

0^^ 

U'DW 

46''  48' 

11°  SO- 

17=53' 

29^  as' 

42=30' 

8=20' 

Abball  Bdk  Ii[d 

fO'OO' 

iWOW 

VfOV 

2=30- 

Alien*). 

is-oo- 

40-00' 

48=00' 

irffHY 

CKlill«lB14 

W2W 

SS-M' 

31°  34' 

17=00-* 

20°  00' 

10=00' 

rhsL.?or?*  '''■  ""•"''              - 

is 

35°  00- 

as- 00' 

Ik 

PS 

c^-it'L,':.'.             :::; 

WOO' 

woo- 

as°oo' 

S°00' 

Of  ay 

aH-oo- 

35°  OO' 

44-00' 

2°0O' 

(■y!^l!lh-Vc  . 

13°  00' 

■  *fl°  OO' 

47°  DO' 

B°00' 

3(f^nr 

60°  oo; 

12°  (W 

KrnQklin"\"l    .  .                            ". 

io;i»; 

iS 

38-00' 
81°  30' 

8^00' 

as;  00- 

35°  00' 

li"yuv:,,%)!'-^\'Aud  2S 

47°  00' 

^foo-t 

Ilu         lit^-J 

Itf-OC 

28"  IW 

40°  00'. 

2=30-' 

Jui:k«m  Olyiiipk.  Kl;^e^li>-.  and  Sultuic 

21*00' 

iWOO' 

40=00' 

16=00- 

16°  oo; 

38°  OO' 

15^  0(1' 

King  B.                                            

48°  00- 

15=00- 

9'**' 

30°  31,' 

arw 

6=00- 

KrilM,    . 

12'ao' 

2^'W 

39=  00- 

2=00- 

S 

l*wL.Si. 

^cZ, 

30°  00' 

6=00- 

r/.r".ni-.hiloTn„„dMI 

ieyr 

60=82' 

10°  27' 

McFirlon  11-T    . 

10"  00- 

43=30' 

10=00- 

Mu»i.|l  4-3S,  .  . 

s=oo' 

40=00' 

36=00- 

D«dG«.lr 

a- 00' 

3Li°  00' 

43=00- 

6=00- 

2=30' 

31=00- 

21=00' 

li-oo' 

45=00- 

in-av 

7=00- 

?! 

Mujer  E  ami  CI                                

s-oo- 

40°  oo; 

45=00- 

10=00' 

rori' 

45°  0.1- 

5=U0-t 

^1 

GASOLINE  AUTOMOBILES  236 

of  comparison  with  the  valve  data  of  American  tj-pes,  TaWe  II.  The 
valve  timing  for  American  cars  as  produced  in  1913  and  1914  is 
given  in  Table  II,  while  Table  I  was  compiled  in  1908;  a  comparison 
which  indicates  in  a  measure  the  advance  in  the  past  five  or  six  years. 
In  studying  these  tables,  it  should  be  home  in  mind  that  all  angles  are 
spoken  of  in  terms  of  the  crankshaft  and  are  usually  referred  to  the 
two  dead  centers,  commonly  spoken  of  as  the  upper  dead  center  aod 
the  lower  dead  center. 

In  Tables  I  and  II,  it  will  be  noted  that  in  so  far  as  maximum 
openings  were  concerned  there  has  been  little  change.  The  earliest 
exhaust  opening  of  1908  was  Mutel  at  02°;  the  earliest  American 
exhaust  opening  of  the  present  is  Simplex  50  at  57°  30'.  The  former 
closed  at  28°,  while  the  latter  closed  at  15°  40',  thus  giving  the  French 
motor  a  total  exhaust  opening  of  270°,  while  the  American  has  but 
2.)3°  10'.  Simplex  is  not  a  representati\e  American  car,  howe\er; 
it  is  a  special  model  with  racing  characteristics,  and  is  built  only  to 
order.    Crescent  and  Reo  are  the  real  leaders. 

With  reference  to  inlet  valves,  the  situation  is  somewhat  similar, 
the  largest  foreign  lag  in  opening  is  the  Unic  with  34°;  while  the 
largest  American  opening  lag  is  the  Hupmobile  with  21°.  In  dosing, 
the  highest  figure  reached  by  the  foreign  product  is  58°  bj'  Peugeot, 
and  on  this  side,  49°  by  Chevrolet.  The  former  shows  also  the 
greatest  total,  254° ;  but  the  largest  American  total  is  that  of  Crescent 
with  245°. 

These,  however,  represent  the  extreme  cases,  and  the  averages 
tell  a  different  story.  The  average  foreign  inlet  opening  (total)  in 
1908  was  232°,  while  the  average  American  inlet  opening  is  now 
239.3°.  Similarly,  with  the  exhaust  total  opening,  the  average  foreign 
figure  then  was  214.5°,  the  a^■e^age  American  figure  is  now  220.2°. 

It  is  unfortunate  that  the  speed  at  full  power  output  of  the 
.\merican  motors  is  not  available  also,  as  that  would  allow  an  even 
more  interesting  comparison  of  the  two  tables.  In  Table  I,  it  will 
be  noted  that  the  motors  are  arranged  in  the  order  of  their  maximum 
speeds.  Were  the  American  speed  figures  available,  it  would  show 
.for  one  thing  whether  speeds  of  today  are,  as  claimed,  so  much 
higher  than  formerly  and  also,  what  is  more  to  the  point,  what  valve 
setting' gives  the  highest  speed.  Referring  to  Table  I,  it  will  be  seen 
that  Unic  with  the  greatest  lag  of  inlet  opening  and  the  %tfc*.\«?.\. 


236  GASOLINE   AUTOMOBILES 

total  inlet  opening  is  next  to  the  highest  in  speed,  whereas  the  others 
having  high  lag  figures  are  all  down  among  the  moderate  speeds. 

Now,  if  the  average  of  the  nuiueroua  examples  of  good  practice 
be  takeii,  it  is  not  a  hard  matter  to  explain  the  form  of  the  cam  and 
its  derivation.  The  height  of  the  upper  surface  of  the  highest  part 
of  the  cam  above  the  surface  upon  which  the  valvt^actuating  device 
normally  rests  determines  the  lift  of  the  valve,  which  is  the  name 
given  to  the  amount  it  is  opened  or  hfted.  This  is  not  really  the  lift 
of  the  valve  because  of  the  fact  that  in  all  valve-operating  systems 
there  is  a  certain  amount  of  clearance  between  the  lower  end  of  tlie 
valve  stem  and  the  upper  end  of  the  valve  lifter  mechanism.  This 
clearance  must  be  taken  up  by  the  cam  before  the  valve  itself  is 
actually  lifted,  so,  to  obtain  the  true  lift,  the  amount  of  the  clearance 
is  subtracted  from  the  lift  as  determined  by  the  cam  height.  Know- 
ing this,  designers  usually  predetermine  the  clearance  and  allow 
for  it  in  the  height  of  the  cams. 

Typical  Valve  Actions.  Figs.  151  and  152  illustrate  the  complete 
valve  action  very  well;  the  former,  that  of  the  Locomobile  Company 
of  America,  Bridgeport,  Connecticut,  showing  the  form  in  which  the 
cam  works  against  a  roller  in  the  bottom  of  the  push  rod.  Thi.s  works 
upward  in  the  push-rod  guide  and  has  a  dirt  excluding  arrangement 


GASOLINE  AUTOMOBILES 


237 


in  this  way  the  wear  is  Retributed  over  the  whole  flat  face,  which 
in  this  construction  can  be  made  much  hirger  than  can  the  face  of 
the  roller.    The  push-  rods  are  of  the  "mushroom"  t>'pe  and  are 


Fie-  151.  Complete  Valrc 
MoSoD  with  Bflib  Path  Rod 
CmrUtg  if  LoeowuMt  Campanr 


ri|.  152.     Complete  ViIte  Motioa 


2.    Complete 
hout  RoOeTiD 


made  of  nickel  steel.  The  push-rod  adjustments  are  completely 
enclosed  but  may  be  readily  reached  without  disturbing  any  other 
unit.  They  may  be  removed  and  replaced  without  removing  the 
valve  springs  or  valves. 


238  GASOLINE  AUTOMOBILES 

Neither  of  these  systems  is  in  decided  favor,  designers  being 
about  equally  dividec!  between  them. 

The  construction  and  operation  of  the  cam  mechanism  is  the 
same  whether  used  in  connection  with  an  exhaust  or  an  inlet  valve; 
as  the  3«me  line  of  rea^ionitig  and  the  same  method  of  procedure, 
in  both  cases,  would  lead  to  the  same  results. 

It  has  many  times  been  tried  and  still  more  often  urged  that 
the  straight  surface  of  the  side  of  the  cam  is  not  conducive  to  the 
best  results,  because  of  the  fact  that  when  the  first  straight  portion 
of  the  cam  surface  strikes  the  cam  roller  it  does  so  with  so  much 
fnrce  that  it  tends  to  wear  the  latter  in  that  direction.  As  for  the 
receding  face,  it  has  been  urged  that  the  ordinary  closing  of  the 
valve  is  ttm  slow  and  that  the  straight  surface  can  be  altered  so  as  to 
allow  of  speeding  up  tlie  downward  movement  of  the  valve.  This  idea 
works  out  into  a  curve; 
''p^|f^|:';{;!;ijJ'!|S|^r;=|'!':^|ig|t!  the  back  of  the  surface  is 

"— j-  ■!■■■-!    |---t----t^^^i:;^l-;-^p'.[i:lJ^     hollowed  out  so  that  as 
T  ,'  j     soon    as  the  cam  roller 

I  y'  :     I     passes  the  center  it  drops 

H': •;[;;;;[;;; ■{j^;;;j|;^;j";T;;:[^^H'^;;iji!|^  vertically,  owing  to  the 

T|:iu{!i^Jj^t^iljin.^:;:-jii:-|:i-i^T^^  tension    of    the    spring. 


GASOLINE  AUTOMOBILES  239 

of  the  piston,  which  results  in  a  much  larger  piston  charge.  The  same 
practice  is  carried  out  with  the  exhaust,  hut  as  the  presstue  is  higher, 
so  large  an  angle  is  not  necessary.  These  actions  take  place  on 
the  back — flat  side — of  the  cam  surface  and  have  given  to  the  high- 
speed automobile  engine  a  larger  charge  and  a  more  complete 
scavenging  effect,  resulting  in  more  power  and  speed  from  the  same 
size  of  cylinder. 

As  proof  of  this  statement,  the  power  curve  of  an  engine  of 
but  Si'inch  diameter  of  cylinder  is  shown  in  Fig.  153.  This  size  of 
six-cylinder  engine  would  be  rated  by  any  formula  at  about  29 
horsepower  at  the  maximum  speed,  and  a  commercially  obtainable 
type  in  this  size  would  doubtless  be  guaranteed  to  deliver  between 
20  and  25  horsepower.  This  engine,  which  is  not  built  for  racing 
purposes,  displays  a  power  curve  which  continuously  rises;  a  speed  at 
which  it  would  turn  downward  has  not  been  obtainable  in  the  tests. 
This  curve  shows  also  that  the  maximum  power  obtained  was  over 
8(),  which  is  nearly  three  times  the  power  of  the  ordinary  engine  of 
this  same  size.  This  result  is  ascrihable  to  superior  valves  and 
superior  attention  to  the  valve  angles  as  governed  by  the  cams. 

Number  of  Valves  per  Cylinder.  Three  Valves  per  Cylinder. 
When  it  was  stated  that  but  two  valves  per  cylinder  were  ordi- 
■  narily  used,  with  one  cam  for  each,  the  majority  case  was  spoken  of. 
But,  as  it  is  a  fact  that  there  are  other  cases  which  differ  from  this, 
it  would  not  be  fair  to  close  the  subject  without  mentioning  them. 
The  most  prominent  advocate  of  air  cooling  in  this  country  and-the 
world,  the  H.  H.  Franklin  Manufacturing  Company,  used  three 
valves,  and  consequently  three  cams,  per  cylinder.  These  three  were 
the  ordinary  inlet;  the  usual  exhaust;  and  the  additional  auxiUary 
exhaust.  By  re-designing  later,  this  complication  was  avoided  and 
the  third  valve  eliminated. 

The  Wisconsin  Motor  G>mpany  has  developed  another  motor 
with  four  valves  per  cylinder  and,  after  a  notable  racing  success, 
has  placed  it  upon  the  market.  Any  maker  desiring  to  do  so,  may 
pivchase  this  and  incorporate  it  in  his  chassis.  This  emphasizes  the 
distance  which  the  sixteen-valve  four-cylinder  motor  has  progressed 
in  the  space  of  a  year  or  so.  A  section  through  this  motor,  both  side 
elevation  and  end  view,  showing  all  the  details  of  the  construction, 
is  shown  in  Fig.  1 54.    A  full  view  of  the  intake  side  is  given  in  F\%.  \&^. 


GASOLINE  AUTOMOBILES 


GASOUNE  AUl'OMOBILES  241 

Four  Valves  per  ('ylinder.  The  very  latest  practice  in  the  way  of 
multiple  valves  is  the  use  of  four  valves  per  cylinder — two  inlets  and 
two  exhausts.  There  are  a  number  of  reasons  why  this  construction 
is  a  good  one.  It  is  said  that  the  area  through  which  the  gases  enter 
and  leave  the  cylinder  can  be  made  greater,  thus  giving  the  same  or 
greater  supply  of  gas  more  quickly  and,  after  using  it,  ejecting  it  with 
the  same  or  a  greater  volume  more  quickly.     The  volumetric  efficiency 


Pia.  t.S.'i.     View  of  iDtakc  Siilc  of  Sixtecn-Valvn  Malur 
C'ourtdv  o/  »'>>cnn.i>i  JToTor  CamiH-nt.  Hilir'iukf.  Ilirottin 

of  the  cylinder  Is  greatly  intTeased  in  this  way,  giving  more  power  and 
ajteed  from  the  same  size  of  cylinders,  so  much  more,  it  is  claimed,  as  to 
make  a  four-cjlinder  engine  with  sixteen  valves  the  equal  of  a  six- 
cylinder  with  but  twelve  valves.  Another  big  advantage  claimed  for 
the  smaller  lighter  valves  of  this  construction  is  that  very  much  lighter 
valve  springs  can  be  used.  This  advantage  was  discovered  by  using 
sixteen  valves  on  four-cylinder  racing  engines  where  the  comotc^TOW"  • 


242  GASOLINE  AUTOMOBILES  ^W 

and  other  pressures  were  enormous.  The  valve  springs  for  the  ordi- 
iiarj'  eight-valve  engine  had  to  be  very  stiff  and,  consequently,  gave 
much  cam  trouble.  The  stiff  springs  dug  out  the  sides  of  the  cams  very 
rapidly  and  also  failed  rapidly  themselves.  With  the  lighter  springs 
which  can  be  used  with  sixteen  valves,  these  troubles  are  eliminated. 
In  the  .'i9  cars  starting  in  the  last  French  Grand  Prix,  all  but 
three  were  four-cylinder  forms.  Of  these  36,  two  ha<!  sleeve  vah'es 
and  three  had  the  usual  number  of  valves,  but  the  other  31  all  had 
sixteen  overhead  valves.  These  were  about  etjually  divided  in 
respect  to  camshafts,  17  ha\'ing  but  one,  14  having  two.  In  the 
recently  developed  Stuiz  motor,  made  by  the  Wisconsin  Motor  Com- 
pany, the  engine  has  the  outward  appearance  of  any  other  T-head 
form,  for  the  use  of  double  the  usual  number  of  valves  does  not  change 
the  exterior  at  all. 

One  Cam  per  Two  Valves  Influences  the  Shape.  A  case  in  which 
the  cam  does  differ  is  that  of  the  use  of  two  overhead  valves  operated 
by  a  single  camshaft,  Fig.  156.  This 
practice  originated  with  the  F.  I.A.T. 
Company',  which  brought  it  out  f(tr 
racing  use  only,  where  it  was  partii-u- 


■    OASOLIKE  AUTOMOBILES  243 

the  low  side.  In  the  form  shown  ip  Fig.  137,  the  eight-cylinder  motor 
used  in  the  Briscoe  38,  made  by  the  Briscoe  Motor  Company,  Jackson, 
Michigan,  there  are  no  unusual  features.  The  single  camshaft  with 
16  cams  b  centrally  placed  in  the  middle  of  the  V  and  operates  tiie 
push  rods,  inclined  outward,  parallel  to  their  respective  groups  of 
cylinders.  A  rocker  arm,  or  follower,  is  used  at  the  cylinder  heads  to 
transfer  this  up-and-down  motion  to  the  valves  which  are  set  in 
the  center  of  the  cylinder  heads  and  are  thus  parallel  to  the  push  rods. 


Ff.  157.     SKtioa  through  Briuoe  Eight,  Showinc  < 

In  the  majority  of  V-t\-pe  motors,  both  eights  and  twelves,  the 
valves  are  in  side  pockets;  the  cylinders  are  of  the  L-type,  and  thus 
there  is  no  radical  innovation  except  the  inclined  push  rods  and  vahe 
systems.  In  a  few  of  these  motors,  however,  a  follower  is  used 
))etween  the  cams  and  the  push  rods  because  of  other  structural  reasons. 

When  any  kind  of  a  cam  follower  differing  from  the  usual  direct- 
lift  push  rod  is  used,  thi;  may  or  may  not  affect  the  shape  of  the  cam. 
r.sually  it  does  not,  so  that  the  shape  does  not  have  to  be  taken  into 
account.  Ordinarily  these  followers  are  used  to  prevent  side  thrust 
on  the  push-rod  guide,  the  follower  itself  taking  all  the  thrvist  mA 


ClASOLINE  AUTOMOBILES 


being  sn  designed  as  to  be  readily  removable  or  adjustable,  to  take 
fare  of  this.     In  cases  where  this  does  not  obtain,  the  object  usuaJly 
^riupht  is  the  rcnmviil  of  noise.     The  two  objects  may  be  combined,  as 
in  the  case  shown  in  Fig.  158.     This 
represents  an  enlarged  view  of  the 
cam  mechanism  of  the  famous  one- 
cylinder  French   car,   Peugeot.     It 
will  be  clear  that  the  action  is  that 
of   one   cam    operating    both    tbe 
exhaust  and  the  inlet  calves  through 
the  medium  of  a  pair  of  levers,  upon 
which  the  cam  works  alternately. 
A  cam   follower  of  somewhat 
different  form,  but  one  achieving  the 
Me  i.'.s    Cam  Mrr-hBmsm  of  Peugeot        Same  results,  Will  be  noted  in  the 
Cadillac  eight-cylinder  motor,  shown 
ill  Fig.  1H4.  where  attention  has  been  called  to  these,  and  also  in  the 
Chalmerssix-fyliiidfT  motor  with  overhead  valves,  shown  in  Fig.  156. 
Difficulties  in  Making  Cams.    There  was  a  time  when  the  pro- 
duction of  a  guild,  accurate  camshaft  was  a  big  job  in  any  machine 


GASOLINE  AUTOMOBILES 


245 


Qrinding  Increases  Accuracy.  An  even  later  improvement  in 
the  way  of  a  machine  for  producing  cams  on  an  integral  shaft  is 
the  grinding  machine  which  has  been  developed  for  this  purpose. 
This  works  to  what  is  called  a  master  camshaft,  that  is,  a  larger 
size  of  shaft  which  has  been  very  accurately  finished.  This  master 
shaft  is  placed  in  the  grinding  machine,  the  construction  of  which 
is  such  that  the  grinding  wheel  follows  the  contour  of  the  very  accu- 
rate master  shaft  and  produces  a  duplicate  of  it,  only  reduced  in  size, 
a  reducing  motion  being  used  between  master  shaft  and  grinder- 
wheel  shaft. 

The  result  of  this  arrangement  is  a  machine  which  is  almost 
human  in  its  action,  for  it  moves  outwanl  for  the  high  points  on  the 
cams  and  inward  for  the  low 
spots  on  the  shaft.  Moreover,  it 
has  the  further  advantage  that 
all  shafts  turned  out  are  abso- 
lutely alike  and  thus  accurately 
interchangeable.  It  allows  also 
of  another  arrangement  of  the 
work,  the  drop  forging  of  the 
shafts  within  a  few  thousandths 
of  an  inch  in  size;  the  surface  of 
skin  is  easily  ground  off  in  one 
operation,  then  the  hardening  is 
done,  and  the  final  grinding  to 
size  is  quickly  accomplished.  In  this  way,  the  shafts  may  be 
produced  more  cheaply  than  was  formerly  the  case  and  have,  in 
addition,  the  merits  brought  out  above,  namely,  greater  accuracy, 
superior  interchangeabitity,  and  quicker  production. 

The  same  process  is  applicable  to,  and  is  used  for,  other  parts  of 
the  modern  motor  car;  thus  crankshafts  are  ground,  pump  and  mag- 
neto shafts  are  finished  by  grinding,  and  many  other  applications  of 
this  process  are  utilized.  The  process  can  be  extended  indefinitely, 
the  only  drawback  being  that  a  master  shaft  is  very  expensive. 

Old  Way  Required  More  Accurate  inspection.  With  the  old 
method  of  making  the  cams  and  shaft  separate,  the  amount  of 
inspection  work  was  very  great  and  represented  a  large  total  expense 
in  the  cost  of  the  car.    Thus,  it  was  necessary  to  prove  up  every  cam 


246  GASOLINE  AUTOMOBILES 

separately,  as  well  as  every  shaft,  ami,  later,  the  cams  and  shaft 
assembled.  One  t>f  the  forms  of  gages  used  for  inspeeting  ct 
(3  shown  in  Fig.  Ifi-.  It  is  in  two  pieees,  dovetailed  together.  This 
allows  of  the  testing  of  many  shapes  of  eam  with  but  one  base  piece  k 
and  a  number  of  upper,  or  profile,  pieces  equal  to  the  number  of  differ-  ii 
cnt  cams  to  be  tested.  To  test,  the  cam  is  slipped  into  the  openitig,  L 
and  if  small,  the  set  screw  forces  it  up  into  the  formed  part  of  the  i, 
gage,  showing  its  deficiencies;  while  if  large,  it  will  not  enter  the  form,  1 1] 


Valve  Timins 
e  of  speed  without  material  alteration  in  the  engine 
V  repair  man  aims  to  get  when  he  goes  over  the  timing  of  the 
motor.  Valve  timing  has  been 
called  an  art,  but  it  is  not;  it  is 
only  the  application  of  common 
sense  and  the  known  vah-e  dia- 
gram to  the  motor  in  an  attempt 
to  get  the  best  all-around  results. 
These,  as  might  he  expected,  are 
a  compromise,  and  that  repair 
man  does  the  best  timing,  who 


GASOLINE  AUTOMOBILES  247 

until  a  mark  or  the  desired  mark  is  brought  up  to  the  pointer.  Thus, 
the  cylinders  are  marked  from  front  to  back  always,  that  nearest  the 
radiator  being  1,  the  next  2,  then  3,  and  the  last,  in  the  case  of  a 
four-cylinder  motor,  4.  In  a  six-cylinder  motor  the  method  is  the 
same  with  the  addition  of  two  cylinders,  the  one  nearest  the  dash 
being,  of  course,  6.  The  flj-wheel  sometimes  has  the  positions  marked 
on  its  surface,  as  well  as  the  valve  operations.  Referring  to  Fig.  162, 
this  shows  the  valve-timing  diagram  of  the  four-cylinder  Over- 
land for  1915.  Xotice  in  this  that  none  of  the  valve  operations  begin 
or  end  on  a  dead  center  point  so  that  even  if  the  centers  are  marked 
on  the  flj-wheel  (as  they  are  in  this  case)  this  is  of  little  benefit  except 
as  will  be  pointed  out.  The  marks  on  the  flywheel  are  as  follows, 
this  showing  also  what  they  indicate.  In  referring  to  these  it  will  be 
remembered  that  on  a  four-cylinder  crankshaft  the  first  and  fourth 
crankpins  are  up  (or  down)  together,  while  the  second  and  third  are 
down  (or  up)  together: 

1-1  UP      Means  that  pistons  in  cylinders  1  and  4  are  in 
their  uppermost  position,  or  at  upper  dead  center. 

2-3  UP     Means  that  pistons  in  cylinders  2  and  3  are  in 
their  uppermost  position,  or  at  upper  dead  center, 

1-4  I-O     Means  that  inlet  valve  of  cylinder  1  or  4  (not  both) 
opens, 

1-4  I-C     Means  inlet  valve  of  cylinder  1  or  4  closes. 

1-4  E-0    Means  exhaust  valve  of  cylinder  1  or  4  opens, 

1-4  E-C    Means  exhaust  valve  of  cylinder  1  or  4  closes. 
'        2-3  1-0      Means  inlet  of  cjlinder  2  or  3  opens. 

2-3  I^      Means  inlet  of  cylinder  2  or  3  closes. 

2-3  E-0    Means  exhaust  of  cylinder  2  or  3  opens. 

2-3  E-C     Means  exhaust  of  cylinder  2  or  3  closes. 

The  firing  order  of  the  cylinders  is  1-3-4-  2.  To  apply  this 
knowledge,  open  the  pet  cocks  so  the  motor  will  turn  over  easily; 
selecting  cylinder  1  to  start  with,  turn  the  flywheel  Until  the  mark 
1-4  UP  cornea  to  the  pointer  at  the  top.  Now  continue  turning 
to  the  left  (at  the  rear  end)  about  an  inch  more  when  the  mark  1-4  1-0 
will  be  seen.  Bring  this  slowly  up  to  the  pointer,  when  the  inlet 
valve  should  just  begin  to  open.  This  can  be  noted  by  feeling  the 
stem,  or  by  placing  a  wire  upon  the  top  of  the  valve  and  noting  when 
it  begins  to  be  pushed  upward  by  the  valve  movement.    If  thv%%ho>M. 


248  GASOLINE  AUTOMOBILES 

happen  in  cylinder  4  instead  of  1,  turn  the  flj-wheel  one  complete 
revolution,  bringing  the  same  point  to  the  top.  If  this  is  entirety 
correct,  the  flj-wheel  can  be  turned  in  the  same  direction  about  5  to  6 
inches  more  than  half  a  turn,  when  the  mark  1-4  I-C  will  appear. 
Turn  slowly  until  it  reaches  the  pointer,  when  the  valve  in  cjlinder  I 
should  be  completely  closed.  This  can  be  determined  again  by 
feeling  of  the  valve  stem  which  should  come  down  to  its  lowest 
position,  or  by  the  wire  on  the  top  of  the  valve.  At  this  point  the 
valve-tappet  clearance  comes  in.  When  the  valve  tappet  has  reached 
its  lowest  point,  and  the  valve  has  been  allowed  to  seat,  the  tappet 
should  go  down  slightly  farther  than  the  valve,  leaving  a  very  sniall 
space  between  the  two.  This  is  the  clearance  and  it  varies  in  normal 
engines  from  .002  inch  to  .012  inch.  In  the  motor  which  is  being 
described  it  is  .012  inch.  The  closest  approximation  to  this  is  an 
ordinary  visiting  card,  which  is  about  .012  iuch  thick;  when  a  motor 
is  handled  which  has  less,  very  much  less,  this  can  be  approximated 
by  means  of  cigarette  pa]>ers  which  are  very  close  to  .003  inch  thick. 
These  are  used  in  the  absence  of  precise  metal  thickness  gages, 
or  feelers,  as  they  are  called. 

( 'alre-Sttm  Clearance.    This  clearance  is  necessary  to  compensate 
for  the  expansion  of  the  \alve  stem  when  it  becomes  highly  heateil 


GASOLINE  AUTOMOBILES 


249 


all  in  good  shape,  this  push  rod  adjustment  is  the  only  valve  adjust- 
ment possible.  If  the  timing  is  not  correct,  that  is,  if  none  of  the  valve 
operations  correspond  with  the  marks  on  the  flywheel  and  the  maker's 
instructions,  then  the  cam  gear  has  been  misplaced. 

ExhausU-Valve  Setting,  The  same  procedure  is  followed  through 
for  the  exhaust  valve  of  the  same  cylinder,  continuing  past  the  1-4  UP 
mark  to  the  mark  1-4  E-0.  At  this  point  the  exhaust  valve  of 
cylinder  1  should  just  begin  to  open.    Then  continue  around  to  the 


Inlet  Opens  /3''  ^.OSe" 
L^e  on  O'rcfjmference. . 
,  Inlet  C/o^es  33  ■-  4.  S36 
\Lohe  on  dn^umfierence. 
£Khou3t  opens  ^3  -SO'-  7353. 
Cb^lu  on  Circumference. 
GchoustCfoses  l£''1.64Q' 
itPte  an  Orcumfmr^nce . 

Motor  nres  I'S^-2 


Fig.  163.     Valve-Timing  Diagram  for  Four-Cyli|ider  Hudson  Motor  Indicating  All  Cylinders 

Courtetp  of  Hudson  Motor  Car  Company,  Detroii,  Michigan 

1-4  El-C  point  where  the  exhaust  valve  of  cylinder  1  is  just  complet- 
ing its  downward,  or  closing,  movement.  If  there  should  be  any  need 
for  adjustment  here,  as  described  previously,  this  should  be  made 
before  proceeding  to  the  other  cylinders.  It  should  be  stated  that 
many  makers  give  the  exhaust-valve  stems  slightly  greater  clearance 
than  the  inlets,  on  the  assumption  that  they  work  with  hotter  gases, 
are  subjected  to  more  heat,  and  should  therefore  expand  more.  The 
make  being  described  has  the  same  clearance  for  both. 

Relation  of  Settings  in  Bxich  Cylinder.    Now,  having  checked  up 
and  adjusted  both  valves  for  cylinder  1,  follow  through  the  saxsl^ 


2&8  GASOLINE  AUTOMOBILES 

process  for  (.'yliiider  4,  and,  after  that,  of  cylinder  2,  then  3,  The  iVia- 
grani,  Fi{{.  102,  sliows  but  tiie  cycle  in  each  cyhnder,  while  tJie  tlescrip- 
tiiMi  above  simpij'  listed  the  markings  to  be  found  on  the'  flj'wheel, 
so  the  additional  diagram,  Fig,  163,  is  given  to  show  the  relation  of 
these  marks  to  one  another.  This  diagram  refers  to  a  different  motor, 
a  Hudson  four-cylinder  model,  and  the  timing  is  indicated  on  the  face, 
hut  the  repair  man  will  understand  that  this  is  done  simply  for  con- 
venience, and  that  these  marks  are  actually  found  on  the  rim.  So, 
too,  the  lines  drawn  down  to  the  center  are  simply  shown  for  con\'en- 
ience  in  indicating  the  angles  and  do  not  appear,  on  the  flywheel. 


GASOLINE  AUTOMOBILES 


251 


on  each  side  (T-head  cylinders),  all  in  the  head  or  half  on  one  mde  and 
the  other  half  in  the  head,  in  short,  regardless  of  the  valve  position. 
Similarly  with  regard  to  numbers,  the  method  holds  good  regardless 
of  the  number  of  valves  per  cylinder.  Moreover,  it  applies  regardless 
of  the  number  and  arrangement  of  the  cylinders,  as  it  is  just  as  good 
for  eights  and  twelves  as  for  the  four  described.  On  V-tjpe  motors 
there  is  a  close  relation  between  the  opposing  cylinders,  right- 
hand  No.  1  and  left-hand  No.  1,  and  this  must  be  taken  into 
account.  In  some  motors  there  is  a  cam  for  each  valve,  in  which  case 
no  trouble  would  ensue;  but  in  others  there  are  but  eight  cams  for 
the  sixteen  valves  {of  an  eight-cylinder  motor).  This  tj'pe  of  shaft 
will  influence  the  timing  diagram,  an<l  in  setting,  tlie  repair  man  will 
have  to  concern  himself  with  the  same  cam  for  two  different  valves — 


J 

1   .B 

-s' 

H 

^ 

^zMifTirf^ 

^ggL 

Urs 

"' 

Fis.  IAS.    CidiUac  Camahalt,  Cun  Followen.  uid  Coven  Removed  [ram  Motor 

one  in  a  cylinder  of  the  right-hand  group  and  one  in  a  cylinder  of 
the  left-hand  group. 

This  statement  will  be  more  plain  perhaps  if  reference  is  made  to 
Fig.  164,  which  shows  a  section  through  the  Cadillac  eight  for  1917, 
and  indicates  how  the  one  cam  operates  two  valves  through  the  hinged 
rocker  arms  A  on  the  left-hand  cylinder  and  B  on  the  right  for  the 
right-hand  cylinder.  By  comparison,  see  also  Fig,  165,  which  shows 
the  plate  C  in  Fig.  164  removed  and  turned  upside  down,  with  the 
camshaft  and  rockers  complete.  '  Not  all  eights  and  twelves  are  like 
this,  nor  do  all  have  a  single  camshaft  set  in  the  middle  of  the  V; 
on  the  contrary,  one  well-known  twelve-cyhnder  motor,  the  Na-  . 
tional,  has  the  valves  on  the  outside  of  the  two  groups  of  cylinders, 
and  thus  has  two  camshafts.  In  such  a  case,  the  timing  method  just 
described  would  be  followed  through  for  all  the  cylinders  on  one  block, 
then  the  same  system  would  be  followed  through  on  the  other  side 
of  the  engine,  one  cylinder  after  another,  on  \hat  Mock. 


252 


GASOLINE  AUTOMOBILES 


Repairing  Poppet  Valves  and  Valve  Parts 

The  interest  of  the  repair  man  in  all  these  valve-motion  part-s  13 
quite  different  from  that  of  the  designer,  for  he  cares  not  so  much 
how  the;'  are  made  as  liow  tiiey  are  taken  out,  repaired,  and  put  back, 
when  accident  or  wear  make  this  work  necessary.  Tii  the  repair  man 
suitable  tools  for  doing  this  kind  of  work  are  also  of  interest,  particu- 
larly those  for  reaching  inaccessible  parts  or  for  doing  things  which 
without  the  tools  could  not  be  done. 

Curing  a  Noisy  Tappet  Valve  springs  and  the  valves  them- 
selves, either  at  the  scat  end  or  at  the  tappet  end,  give  the  most 
trouble.  For  example,  when  the  clearance  between  the  end  of  the 
tappet  and  the  end  of  the  valve  (usually  from  .003  to  .008  inch)  is 
too  great,  u  metallic  click  results.  Often  this  noise  from  the  tappet 
is  mistaken  for  a  motor 
knock;  but  the  skilled 
repair  man  has  little 
trouble  in  finding  and 
remedying  if,  for,  even 
if  he  cannot  measure  in 
thousandths  of  an  inch, 


GASOLINE  AUTOMOBILES 


253 


rests  against  solid  metal.  The  outer  end  can  now  be  pressed  down, 
and,  with  the  inner  end  acting  as  a  lever,  the  valve  can  be  pressed  off 
its  seat  and  out  very  quickly. 

To  make  this  clearer,  the  rod.  Fig.  166,  is  indicated  at  A,  while 
the  dotted  line  shows  how  it  is  pressed  down  and  the  valve  forced  out. 
The  garage  man  can  elaborate  upon  the  tool  when  making  it  for 
himself  bj'  using  square  stock; 
it  has  the  inner  end  forked  so 
as  to  bear  on  each  side  of  the 
valve.  The  form  pointed  out 
above  is  the  simplest,  cheap- 
est, and  easiest  to  make. 

Removing  Valve  Spring. 
Taking  out  the  valve  spring 
is  frequently  difficult  for 
various  reasons;  perhaps  the         ^    ,«,    r-    ■   .,  j  -,-   ,,    ., 

'   r  c  Pig   ie7,     Euily  Mmdf  Tno]  Sot  RemovinK 

springs  are  very  stiff,  or  they  ''■'™  spriim 

may  have  rusted  to  the  valve  cups  at  the  bottom,  or  the  design 
may  not  allow  room  enough  to  work,  etc.  At.  any  rate  the 
removal  is  difficult,  and  a  tool  which  will  help  in  this  and  which 
is  simple  and  cheap,  is  in  demand.  Many  motor  cylinders  are  cast 
with  a  slight  projection,  or  shelf,  opposite  the  valve-spring  positions, 
so  that  one  only  needs  a  tool  that  will  encircle  the  lower  end  of  the 
valve  spring  and  rest  upon  this  ledge  and  give  an  outer  leverage. 

Types  of  Valve  Removers. 
In  working  on  cylinders  that 
do  not  have  this  cast  pro- 
jection, a  tool  like  that  shown 
in  Fig,  167  is  useful.  It  con- 
sists of  a  yoke  for  encircling 
the  lower  end  of  valve  spring 
and  cup,  with  a  long  outer 
arm  for  prying,  and  a  slot  into  which  a  drilled  bar  is  set,  Thb 
bar  is  placed  in  various  positions  according  to  the  kind  of  motor 
which  is  being  worked  on;  when  removing  a  valve-spring  kej-,  the 
lower  end  of  the  bar  rests  upon  the  crankcase  upper  surface,  or 
_upon  the  push-rod  upper  surface  if  that  is  extended.  After  slipping 
the  grooved  yoke  under  the  spring  cup,  a  simple  pressure  on  VW  oxAet 


Type  d(  Vkln.Spniia  Tool  WUch 
Lemva  the  Iluilia  Free 


2U 


GASOLINE  AUTOMOBILES 


end  raises  the  valve  so  the  key  can  be  withdrawn.  Then  the  removal 
of  the  tool  allows  the  valve  spring  to  drop  down,  and  the  valve  is  free. 
The  valve  spring  may  be 
removed  in  two  other  ways  by 
the  use  of  the  two  tools  shown  in 
Figs.  168  and  169.  In  the  former, 
the  idea  is  to  compress  the  -spring 
oiilj',  no  other  part  being  touched. 
This  tool,  once  set,  will  continue 
to  hold  the  spring  compressed, 
leaving  the  hands  free — a  decided 
advantage  o\er  tlie  tool  sliown in 
Fig.  167.  This  device  consists,  as 
the  illustration  shows,  of  a  pair 
of  arms  with  forked  inner  ends 
and  with  outer  ends  joined  by  a 
pin.  A  bent-handled  screw  draws 
the  ends  together  or  separates 
them,  according  to  which  way  it 
is  turned. 


GASOLINE  AUTOMOBILBS 


255 


double-ended  wrench  by  means  of  a  wire  attached  to  the  water 
pipe  on  top  of  the  motor;  adjusting  the  length  of  it  so  that  the 
end  of  the  wTench  would  just  slip  under  the  valve  key,  he  was 
able  to  remove  the  pin,  which  freed  the  spring  and  thus  the 
valve.  Practically  the  same  thing  was  evolved  by  another  repair 
man  who  took  a  wrench  of  this  type  and  drilled  a  hole  through  the 
center  of  the  handle  which  was  first  twisted  through  a  right  angle. 
Then  he  bent  a  piece  of  stout  wire  into  the  form  of  a  hook,  one  end 
through  the  wrench,  the  other  over  some  projection  on  the  engine. 
With  the  hook  removed,  the  wrench  was  not  radically  different  from 
any  other  and  could  be  used  as  freely;  with  the  hook  in,  he  had  a 
simple  valve-spring  removing  tool. 


Tig.  171.     Method  of  Comi 


Twelve-Cylinder  Valve  Remover.  One  of  the  objections  raised  to 
the  twelve-cylinder  motor  is  the  trouble  of  removing  and  grinding  all 
the  valves.  The  Philadelphia  Branch  of  the  Packard  Company  has 
overcome  this  disadvantage  by  constructing  the  special  tool  shown  in 
Fig.  171.  This  lifts  the  whole  24  valves  at  once.  It  consists  of  the 
central  stand,  which  rests  on  the  flat  top  of  the  crankcase,  having  a 
long  arm  and  connected  levers  at  the  bottom  to  work  the  spring  com- 
pressors. These,  as  will  be  seen  at  A  and  B,  are  really  the  special 
feature  of  the  outfit,  as  they  are  specially  constructed  to  fit  around  the 
valves  in  Sets  of  12  each.  A  ratchet  holds  the  device  locked,  so  that 
after  it  is  applied  and  fitted  to  all  the  valves,  they  can  be  forced  up 
and  locked ;  then  the  matter  of  valve  removal,  regrindmg,  ^n^te^^ax^Sr- 


256 


GASOLINE  AUTOMOBILES 


.  ment  can  be  Iiunclle«l  for  the  whole  24.    At  its  conclusion,  the  rigging 
can  be  unlockctl  aiul  all  24  valves  freed  at  once. 

Holding  Valve  Springs  Compressed.  Many  times  there  is  a 
need  for  hohllng  the  spring  in  its  compressed  form,  as,  for  instance, 
when  the  vahe  is  removed  with  the  positive  certainty  that  it  will  be 
replaced  within  four  or  live  minutes.  In  such  a  case  a  clamp  which 
will  hold  it  in  compression  is  \'ery  useful,  for  it  saves  both  time  and 
work.  These  may  be  made  to  the  form  shown  in  Fig.  172  in  a  few 
minutes'  time,  for  tlioy  consist  simply  of  a  pair  of  sheet-metal  strips 
with  the  ends  bent  over  to  form  a  very  wide  U-shape.  A  pair  of 
these  is  nia<le  fur  eaeli  se])arate  make  of  valve  spring,  because  of  the 
varjinj;  lengths,  but  they  are  30 
easily  and  quickly  made  that 
this  is  no  disadvantage. 

In  many  shops,  after  getting 
in  the  habit  of  making  these 
clamps,  the  workmen  take  this 
way  of  replacing  the  spring  in 
preference  to  all  others.  After 
removal  of  the  valve,  the  spring 


GASOLINE  AUTOMOBILES 


257 


heating  to  a  blood-red  color  and  quenching  in  whale  oil.    If  this 
is  not  successful,  new  springs  are  advised. 

Adjustii^  Tensktii  of  Valves.  Unless  all  the  valves  on  a  motor 
agree,  it  will  run  irregularly,  that  is,  all  the  exhausts  must  be  of 
the  same  tension,  and  alt  the  inlets  must  agree  among  themselves, 
though  not  necessarily  with  the  exhausts.  Many  times  irregular 
running  of  this  kind,  called  galloping,  is  more  difficult  to  trace 
and  remove  than  missing  or  some  other  form  of  more  serious  trouble, 
and  it  is  fully  as  anno>'ing  to  the  owner  as  missing  would  be. 

To  be  certain  of  finding  this 
trouble,  the  repair  man  should 
have  a  means  of  testing  the 
strength  of  springs ;  a  simple  device 
for  this  purpose  is  shown'  in  Fig. 
1 73.  As  will  be  seen,  this  consists 
of  sheet-metal  strips  and  connect- 
ing rods  of  light  stock,  with  a  hook 
at  the  top  for  a  spring  balance  and 
a  connection  at  the  bottom  to  a 
pivoted  hand  lever  for  compress- 
ing the  spring.  By  means  of  the 
center  rod  at  R  and  the  thumb 
screw  at  the  bottom,  the  exact 
pressure  required  to  compress  the 
^ring  to  a  certain  size  may  be  ' 
determined.  Suppose  the  spring  s^.  i 
should  compress  from  4  inches  to 
3}  inches  under  50  pounds.  By  compressing  it  in  the  center  portion 
of  the  device,  so  that  the  distance  between  the  two  adjacent  strips  of 
metal  indicated  by  S  is  just  3)  inches,  the  spring  balance  should  show 
just  50  pounds.  If  it  shows  any  less,  the  spring  is  too  weak  and 
should  be  discarded;  if  it  shows  any  more,  it  is  stronger  than  normal 
— which  is  desirable  if  all  the  other  springs  on  the  same  en^e  are 
also  stronger. 

If  only  a  quick  comparison  of  four  springs  is  desired,  the  device 
can  be  made  without  the  bottom  lever,  as  the  setting  of  S  at  a  definite 
figure — say  to  a  template  of  exact  length — would  call  for  a  certain 
reading  of  the  scale  of  the  spring  balance. 


imrAo  RigEiDiE  for  Tsting  V 
■■  Pmaucs  ud  Strelvth 


GASOLINE  AUTOMOBILES 


Cutting  Valve-Key  Slots.  Cutting  valve-key  slots  in  valve 
stems  is  another  mean  job  which  the  repair  man  frequently  meets. 
He  runs  across  this  in  repairing  old  cars  for  which  he  haa  to  make 
new  valves;  anil  at  other  times  for  other  repairs.  The  best  plan  b  to 
make  a  simple  jig  which  will  hold,  guide,  and  measure  all  these  thing! 
at  once,  as  all  are  important.  Such  a  jig  is  shown  in  Fig.  174.  It  con- 
sists of  a  piece  of  round  or  other  bar  stock,  in  which  a  central  longi- 
tudinal hole  is  drilled  to  fit  the  valve  stem,  one  end  being  threaded  foi 
a  set  screw.  Near  the  other  end  of  the  jig,  three  holes,  of  such  a 
diameter  as  to  correspond  with  the  width  of  key  slot  desired,  are 
drilled  in  from  the  side.  These  are  so  placed  that  the  length  from 
the  top  of  the  upper  hole  to  the  bottom  of  the  lower  gives  the  length 
of  key  seat  desired.  Opposite  the  three  drilled  holes  and  at  right 
angle;  to  them,  another  hole  is  drilled  and  tapped  for  a  set  screw. 
To  use  the  device,  slip  the 
valve  in  place  and  set  the  bottom 
screw  of  the  jig  so  as  to  bring  the 
three  drilled  holes  at  the  correct 
height  for  the  location  of  the  key 
seat.    Then   the  three  holes  are 


^3j;^"p=-^l 


GASOLINE  AUTOMOBILES 


should,  and  the  result  is  failure  to  discover  something  in  the  way  of 
soot  or  dust  caught  in  between  the  valve  and  seat,  which  is  being 
gradually  pressed  into  the  seat, 

Regrinding  Process.  When  either  the  valve  head  or  seat  has 
become  worn  or  pitted,  it  must  be  reground  aa  follows;  Secure  a  small 
amount  of  flour  of  emery,  the  finer  the  better,  and  mix  this  into  a  thin 
paste  using  cylinder  oil,  or  graphite,  or  both.  Loosen  the  valve,  dis- 
connect alt  attachments,  remove  the  valve  cap  above,  and  free  the  valve 
in  a  vertical  direction.  Now  lift  it  out,  place  a  daub  of  the  emery 
paste  on  the  seat,  and  replace  the  valve.     With  a  large  screwdriver 


Fig.  176.     Ti 


I.  UnDg  ft  ScrewdjiTer; 


press  the  valve  firmly  in  place,  at  the  same  time  rotating  it  about 
one-fourth  of  a  turn  to  the  right  and  then  the  same  amount  to  the  left. 
This  is  shown  in  Fig.  175-j1,  in  which  S  is  the  screwdriver,  V 
the  valve,  and  VS  the  valve  seat.  Note  how  the  right  hand  presses 
down  on  the  screwdriver  and  turns  it  at  the  same  time.  While  this 
is  being  done,  the  left  hand  should  be  held  right  below  the  valve 
stem  with  one  finger  just  touching  it.  After  moving  back  and  forth 
about  eight  or  ten  times,  lift  the  valve  ofF  its  seat  with  the  finger, 
turn  it  through  a  quarter-turn,  and  drop  it  back  into  place.  Then 
repeat  the  grinding  until  the  whole  circle  has  been  covered  several 
times.  Then  remove  the  valve  and  clean  off  both  moving  member 
and  seat  with  gasoline.    Mark  the  seat  on  the  valve  with  a  sU%Kl 


960 


GASOLINE  AUTOMOBILES 


touch  of  Prussian  blue,  replace  the  valve,  and  twirl  it  around  several 
times  so  as  to  distribute  the  color.  Remove  the  valve  without  touch- 
ing the  seat  portion  on  it  or  in  the  cylinder,  and  esamine  both.  If 
the  grinding  process  has  been  complete  and  accurate,  the  color  will 
have  been  distributed  in  a  continuous  band  of  equal  width  all  around 
the  surface.  If  not  continuous,  or  not  of  equal  width  all  around,  the 
task  is  but  partially  completed  and  must  be  continued  until  the  full 
streak  results.  On  the  first  attempt  at  this  rather  delicate  piece  of 
work,  it  is  well  to  call  in  an  expert  repair 
man  to  examine  and  pass  upon  the  job. 
In  Fig.  17.5-B  the  same  process  is 
shown,  but  a  brace,  screwdriver  and  bit  are 
used  in  place  of  the  slower  screwdrivet. 
This  method  would  hardly  be  advocated 
for  an  amateur  attempting  his  first  job  of 
valve  grinding,  but  as  soon  as  some  pro- 
ficiency has  been  attained,  it  is  the  best, 
quickest,  and  most  thorough  method. 

There  are,  of  course,  a  niunber  of  toob 
now  on  the  market  for  grinding  valves; 


GASOLINE  ArroMOBILES 


261 


be  taken  up  until  thm  is  bat  a  fnr  tboasuMhlis  of  an  indi  between 
the  >-aIve  tappet  and  the  lowerendof  Uienilve  stem.  Agoodwayto 
measure  thisistoadjust  nmiloDethicknessof  tissue  paperwill  just  pass 
between  the  two:  then  there  bapproxiniately  .008  indi  between  them. 

Valve  Endosnres.  On  many  oM  cars,  the  arrangement  of  Uie 
valve  merfianism  h  stkA  that,  aftn-  se\-era]  thousand  miles  ha^T 
been  covered,  the  %'alve  motions  will  become  noisy  and  nothing  that 
can  be  doae  will  stc^  this.  In  that  ca^.  the  best  f^u  is  to  endose 
each  one  of  them  in  a  pasteboard  or  other  tube  and  thus  keep  the 
noise  in.     In  fact,  this  is  _ 

a  good  plan  even  for  later 
models.  The  method  of 
doing  this  is  indicated  in 
Fig.  176,  in  which  the 
pasteboard  tube  is  shown 
in  place  around  the  valve 
mechanism.  As  this 
should  be  a  tight  6t  be- 
tween the  crankcase  at 
the  bottom  and  the  C}'1- 
inder  at  the  top,  the  tube 
must  be  slit  in  order  to 

get  it  on.     Vkhea    this  

has  been  done,  however, 

the  tube  can  be  drawn  together  ^nd  fastened  by  means  of  wire  or 
otherwise.  Besides  reducing  the  noise,  it  will  be  found  that  the 
valve  sv-stem  parts  will  get  better  lubrication  in  this  way  and  will  pick 
up  less  dirt  and  dust,  thus  wearing  less. 

Taking  Out  a  Valve.  On  some  engines  the  job  of  taking  out  a 
valve  or  valves  is  not  as  simple  as  it  sounds.  On  an  overhead  engine, 
or  en  engine  with  overhead  valves,  it  is  not  as  hard  work  as  on  an 
engine  with  the  valves  in  pockets  in  the  side  of  the  cylinder,  for  the 
overhead  valves  are  usually  set  into  removable  seats.  The  latter 
come  out  by  simply  taking  off  a  yoke  or,  at  most,  a  pair  of  nuts,  and 
then  the  cage  and  with  it  the  valve  lifts  right  out,  spring  and  all. 
This  latter  is  mentioned  because  with  the  ordinary  L-  or  T-iead  motor, 
it  is  the  spring  which  causes  all  the  trouble.  Fig.  177  shows  the 
process  of  removingthe  cage  and  valve  from  an  engine wvl^v  ovet\iea& 


Fir  177. 


GASOLINE  AUTOMOBILES 


valves  (this  is  the  engine  made  for  the  Tniscott  boats).  To  remove 
these,  the  valve  tappet  is  held  out  of  the  way  and  the  cage  unscrewed. 
Troubles  with  Inlet  Valve.  The  inlet  valve  is  often  the  seat  of  the 
trouble,  and  missing  here  is  generally  caused  by  a  weak  or  broken 
spring,  a  bent  stem,  or  a  carbonized  valve.  If  the  valve  spring  has 
lost  its  temper  and  broken  down,  the  tension  wilt  be  insufficient  to 
property  hold  the  valve  on  its  seat,  and  the  gas  will  partially  escape 
and  so  cause  missing.  The  insertion  of  an  iron  washer  or  two  will 
increase  the  tension  of  the  defective  spring  and  serve  as  a  temporary 
road  repair.  A  broken  spring  may  be  similarly  repaired  by  placing  a 
washer  between  the  broken  ends. 
A  bent  valve  stem  should  be 
taken  out  and  carefully  straight- 
ened by  laying  it  upon  a  billet  of 
wood  with  another  block  inter- 
posed between  it  and  the  ham- 
mer. Only  a  very  little  force  is 
needed,  and  the  stem  should  be 
repeatedly  tried  until  it  slides 
freely  in  its  guide. 

VatveTiming Pears.    As  has 


GASOLINE  AUTOMOBILES  263 

to  use  center  punch  marks,  one  mark  between  the  teeth  on  one  and 
on  the  tooth  meshing  with  these  on  the  other.  Then,  if  a  second 
place  has  to  be  marked,  two  prick-punch  marks  are  used  in  a  similar 
manner,  and  if  a  third  is  marked,  three  punch  marks.  A  third  method 
is  the  use  of  numbers,  the  first  pair  marked  being  numbered  t  on  each 
gear  at  the  point  of  meshing,  the  second  pair  marked  2  on  each,  ete. 
For  the  second  method,  all  that  is  necessary  is  a  prick  punch  and 
hammer,  used  in  the  manner  shown  in  Fig.  178.    When  there  are  but 


PIc.  ITS.     Method  at  Marking  l^miiig  Otan  br  Meuu 


two  gears,  as  in  the  case  shown,  it  is  easy  to  make  one  hole  between 
two  teeth  on  one  gear  and  another  which  lines  up  with  it  and  as  close 
to  it  as  possible  on  the  other  gear.  Where  there  are  three,  four,  or 
more  gears,  the  usual  practice  is  to  make  the  first  and  third  with  two 
prick-punch  marks  on  each,  the  others  with  three,  four,  etc. 

For  the  third  method,  or  the  use  of  numbers,  see  the  set  of  gears 
shown  in  Fig.  179.  This  figure  is  that  of  the  engine  whose  timing 
was  described  and  shown  in  Fig.  162.    It  has  four  gears;  from  rif^Kt 


m 


GASOLINE  AUTOMOBILES 


to  left  they  are  camshaft  gear,  crankshaft  gear,  idler  gear,  and  magneto 
gear.  As  will  !>c  noted,  the  crankshaft  gear  meshes  with  two  othere, 
s"  it  must  he  marked  in  two  places,  7  where  it  meshes  with  the  cam- 
shaft gear  ami  2  where  it  meshes  with  the  idler.  A  moment's  thought 
will  show,  however,  that  it  could  never  be  replaced  in  the  wrong 
manner,  since  it  is  marked  only  on  the  outside  face,  its  7  and  ;?  figure.'i 
show  where  it  matches  a  /  mark  on  one  gear  and  a  2  mark  on  another. 
Chain  Drive  for  Camshafts.  The  silent  chain  has  gained  much 
popularity  for  camshaft  and  accessory  drives  in  the  last  two  years  for 
a  number  of  reasons.     It  saves  the  use  of  idler  gears  in  such  cases  as 


GASOLINE  AUTOMOBILES 


265 


Etprocket  at  CC.  This  makes  its  correct  adjustment  easy.  A 
straightedge  is  laid  across  the  case  marks,  the  crankshaft  sprocket 
turned  to  this  line,  and  the  chain  put  in  pta^e  but  not  joined;  finally 
the  camshaft  sprocket  is  turned  to  the  tine,  the  chain  moved  to  hold 
it  in  this  position,  and  its  ends  joined.  By  this  method,  there  would 
be  two  possible  positions  for  the  camshaft  sprocket,  as  compared  with 
the  crankshaft  sprocket  and  line  on  the  case.  These  could  readily 
be  distinguished  as  correct  and  in- 
correct  as  soon  as  the  chain  is  applied 
and  the  engine  given  a  couple  of 
turns.  If  incorrect,  it  is  simply  a 
matter  of  lining  them  up  again  by 
opening  the  chain,  turning  the  cam- 
shaft gear  through  ISO  degrees, 
putting  the  chain  back  on  and  join- 
ing its  ends  a  second  time. 

Other  Parts  ol  Valve  System. 
There  are  a  number  of  other  parts  in 
the  valve  group  whose  names  and 
functions  should  be  explained,  for 
these  are  of  interest  to  both  the 
owner  and  the  repair  man.  The 
repair  man  should  know  what  work 
they  do  in  order  to  be  able  to  repair 
them  successfully.  Fig.  ISI  shows 
an  overhead-valve  system  in  which 
the  camshaft  is  in  the  usual  place 
in  the  crankcase;  long  push  rods  are 
used  with  rocker  arms,  or  levers,  at 
tbe  top.  This  is  mentioned  because 
many,  in  fact  the  majority  of,  motors  with  overhead  valves  have 
an  overhead  camshaft  like  the  Chalmers,  Fig.  156. 

In  this  figure  the  various  parts  are  named.  The  rotation  of  the 
camshaft  brings  the  cam  around  so  that  it  lifts  the  roller  and  plunger 
which  has  the  adjuating  screw  and  its  lock  nut  at  the  top.  The  top 
of  the  roller  bears  against  the  bottom  of  the  piwA  rod,  and  the 
upper  end  of  the  push  rod  operates  the  valve  rocker  lever  which  is  held 
in  the  support.    At  the  other  end  of  the  valve  tockei  Wvei  s.  loUer 


GASOLINE  AUTOMOBILES 


presses  against  the  top  end  of  the  valve  stem  and  pushes  it  down  from 
off  tlie  talce  sent  against  the  pressure  of  the  spring,  the  upper  end 
of  which  is  held  by  the  cup  and  cup  pin  and  the  lower  end  rests 
upon  tlie  upper  surface  of  the  value  cage.  The  latter  is  made  so 
that  its  central  upward  extension  also  forms  the  mlve  guide.  The 
valve  cage  is  screwed  down  into  the  cylinder  head  with  packing  to 
make  a  gas-tight  joint.  It  carries  the  value  seat  and  is  cored  out  for 
the  gas  passages  through  which  the  gas  enters  (or  leaves). 

When  the  valve  in  pockets  is  substituted  for  the  long  push  rod,  in 
either  the  L-head  or  in  the  T-head  cylinder,  the  construction  is  about 
the  same  as  if  the  upper  right-hand  valve  group  were  lifted  bodily, 
turned  upside  down,  and  placed  so  that  the  upper  end  of  the  valve 
stem,  upon  which  tlie  roller  rests,  comes  into  contact  with  the  adjust- 
ing screw.  In  that  case,  the 
valve  lifter  would  be  called  the 
push  rod,  and  .the  valve  cage 
would  bectHnea  part  of  the  cylin- 
der with  an  integral  or,  in  some 
cases,  a  removable  valve  guide. 
Push  Rods  and  Guides.  As 
?  seen  from  Fig.  181  and 


gasoliKe  automobiles 


267 


the  yoke  that  rests  upon  shoulders  on  the  push  rods  and  holds  them  in 
place.  From  a  repair  man's  point  of  view,  the  latter  construction  is 
better,  for  the  push  rods  can  be  removed  and  replaced  much  more 
easily  and  quickly. 

Valve  Cage  Repairs.  When  the  valves  are  in  overhead  cages,  it 
is  highly  important  that  they  fit  tightly  in  the  cylinder  head;  they 
must  be  ground  in  as  carefully  and  as  tightly  as  the  valves  are  ground 
into  their  seats.  Where  a  shop  handles  a  good  many  motors  of  the 
overhead-valve  tj-pe,  it  is  desirable  to  make  a  rig  to  do  the  grinding 
easily.  One  of  these  rigs  is  shown  in  Fig.  183.  It  consists  of  a  shaft 
and  handle  with  lock  nuts  for 
the  valve  cages  used  on  Buick 
cars.  On  these  cars,  it  is  in  two 
parts;  the  cage  proper,  and  the 
lockingmemberwhich  screws  into 
the  cylinder.  Obviously  the  cage 
is  the  one  to  be  ground  in.  The 
rig  shown  slides  in  the  central 
opening,  that  is,  fits  in  the  valve 
guide,  and  has  a  lock  nut  top 
and  bottom  to  fasten  it  tightly. 
When  fitted  into  place  firmly,  the 
right-angle  bend  in  the  rig  gives 
a  handle  by  means  of  which  the 
cage  can  be  lifted  in  and  out  and, 
what  b  more  important,  rotated 
on  its  seat.  When  the  cage  is 
prepared,  the  seat  is  given  a  little  oil  and  emery  or  oil  and  powdered 
glass  or  prepared  valve  grinding  composition,  the  cage  is  set  in  place 
and  ground  in  the  same  as  a  valve,  that  is,  with  one-third  to  one-half 
rotations  in  one  position,  then  lift,  move  around,  and  repeat  in  the 
new  position,  continuing  this  until  the  whole  surface  of  the  cage  in  the 
cylinder  has  been  covered  twice.     This  should  result  in  a  good  seat. 

When  the  valves  in  an  overhead  motor  need  grinding,  the  valve 
and  cage  are  taken  out  completely  and  held  in  an  inverted  position 
io  a  vise  or  other  clamp,  and  the  valve  ground  In  to  the  seat  in  the 
cage  in  the  regular  way.  It  is  said  this  can  be  done  very  rapidly  and 
well  by  chucking  the  valve  stem,  as  it  projects  from  \.\ie  c&f^,  \u  «. 


GASOLINE  AUTOMOBILES 


lathe  rotating  at  a  very  slow  speed,  and  operating  the  cage  by  hand, 
that  is,  shde  the  cage  back,  apply  grinding  conipoiind,  then  move  the 
cage  up  to  the  rotating  valve  and  hold 
it  with  tlie  hand  while  the  valve  is 
turniug  with  the  lathe.  In  holding  it 
tlma,  the  pressure  endwise  should  be 
very  light. 

Valve  Guides.  The  valve  stem 
must  be  a  tight  fit  in  the  guide,  other- 
wise air  will  leak  through  into  the 
combustion  chamber  and  dilute  the 
mixture,  or  the  compression  will  leak 
out,  or  both.  Any  valve  leak  will  affect 
the  running  of  the  motor,  so  it  should 

F\f   IM      NIrlli.H!  of  Carina  \■^h■e-  ^  Stoppcd  at  OUCC.      TwO  methods  of 

uidt  L^Bh  tjiurkiy  rnij  c  tapiy  temporarily  remedying  small  leaks  are 
shown  in  Figs.  1 84  and  1 85.  A  simple  leather  washer  with  a  small  hole 
through  the  center,  which  fits  tightly  over  the  valve  stem,  is  pressed 
up  around  the  outside  of  the  guides,  as  shown  in  Fig,  184,  This 
simple  re[mir  was  very  cfl'ecti\'e,  and  the  leather  washers  lasted  an 


GASOLINE  AUTOMOBILES 


wearing  surface.  This  len^  and  the  need  for  accuracy  through- 
out makes  the  valve-guide  bole  an  awkward  surface  to  repair. 
When  worn  beyond  any  hope  of  simple  repair,  it  ia  best  to  ream  it  out 
and  press  in  a  bronze  bushing  so  that  the  valves  can  still  be  used. 
An  excellent  tool  for  this  purpose,  developed  for  Dodge  motors  but 
which  is  usable  for  almost  any  motor,  is  shown  in  Fig.  186.  This  con- 
sists of  a  high  threaded  bushing  which  is  clamped  to  two  diagonal 
cylinder  studs.  The  thread  inside  the  bushing  is  very  fine.  A  long 
tube,  with  the  lower  end  bored  out  to  take  a  standard  reamer,  is 
screwed  into  it.  The  top  is  squared  and  a  handle  is  made  to  fit  it. 
When  the  handle  is  turned,  the 
tube  is  gradually  screwed  down 
into  the  cylinder,  carrying  the 
reamer  slowly  but  truly  down 
through  the  valve  guide.  This 
rigging  is  simple,  easily  made,  and 
gives  accurate  results.  When 
the  valve-guide  hole  is  reamed, 
the  bushing  can  be  turned  up 
and  pressed  in  with  any  form  of 
shop  press. 

Valve  Caps.  The  plug  which 
fits  into  the  top  opening  in  the 
c>'liiider  through  which  the  valve 

L  is  put  in  place  and  removed  is 

'    called  the  valve  cap.    Sometimes 

I    it  has  external  hexagonal  sides 

I    so  it  can  be  easily  removed,  but 

.  more  often  it  has  an  internal  hexagOn,  or  internal  ribs.  The 
latter  form  can  be  removed  most  easily  by  constructing  a  special 
tool,  consisting  of  a  cylindrical  member,  with  a  bottom  diameter 
slightly  larger  than  the  opening  in  the  valve  cap,  with  four  (or 
more)  teeth,  or  projections,  set  into  the  bottom  of  this  to  match  the 
ribs  inside  the  cap.  A  central  hole  is  drilled  for  a  bolt  with  spark- 
plug threads  at  the  bottom.  To  use  the  member,  remove  the  spark 
plug,  set  the  device  in  place,  slip  the  central  bolt  in  and  screw  it  down 
into  the  plug  to  hold  the  whole  thing  in  place,  then  apply  a 
wrench  to  its  upper  square  surface  and  remove  the  valve,  cap  sni^  t^. 


_       .IT  Reunina  Out  Vahrv 
^Ira  Guide  Hola 
run 'tf  Motor  IKorU" 


270 


GASOLINE  AUTOMOBILES 


It  can  be  laid  aside  just  as  removed,  and  when  the  work  is  concluded, 
the  whole  thing  can  be  screwed  back  in,  the  central  screw  loosened, 
and  the  rig  removed  from  the  cap. 
Sometimes  the  threads  in  tb* 
cylinder  into  which  the  valve  cap 
screws  become   dirt\,   slightij'   cul 
up,  or  marred  so  that  the  cap  docs 
not  screw  in  or  out  readily.     Bv 
taking  an  old  valve  cap  of  the  same 
motor  and  same  threads  and  fluting 
these  in  a  milling  machine,  as  indi- 
cated in  Fig.   187,  a  neat  tap  can 
be  made  which  will  clean  out  the 
Thrtrirfm.f  \iiK<Tup  threads  in  a  Hffv.     It  is  simple,  effcc- 

tive,  and  cheap. 
Cleaning  Camshaft  Gears.  On  tlie  majority  of  engines,  the  cam- 
siiaft  and  other  gears  or  the  silent  chain  which  replaces  them,  are  lubri- 
cated automatically  by  the  running  of  the  engine  as  they  are  by-passed 
in  on  the  engine  lubricatinp;  system.  This  is  an  exc'cllent  feature. but 
it  leads  to  ncplcct.     These  gears  or  sprockets  are  sure  to  wear,  and 


GASOUNE  AUTOMOBILES 


271 


Twisted  Camshafts.  With  the  present  form  of  camshaft  having 
the  cams  forged  integral,  troubles  and  irregularities  between  one 
cylinder  and  another,  which  the  repair  man  finds  difficult  to  trace  or 
run  down,  sometimes  develop  in  the  running  of  the  engine.  A  fairly 
light  camshaft  will  sometimes  become  twisted,  usually  right 
at  a  cam  where  the  stress  is.  When  trouble  of  this  kind  is  indi- 
cated, the  camshaft  should 
be  removed  and  tested.  A 
good  way  to  do  this  is  to 
place  the  shaft  in  the  milling 
machine  with  the  index  head 
set  so  that  one  revolution  of 
the  shaft  can  be  divided 
into  four  equal  parts.  Place 
a  thin  disc  in  the  arbor, 
then  mount  the  shaft  and 
bring  it  up  to  the  disc. 
Choose  one  of  the  cams  and 
set  the  disc  to  the  exact 
center  of  the  j)oint  of  it. 
Then,  by  turning  the  shaft  a 
quarter-turn  each  time,  the 
other  cams  can  be  tested  with 
their  relation  to  this  one. 
Sometimes  a  difference  of  J 
inch  will  be  found  in  this 
way.  "Hie  lay-out  for  this  is 
seen  m  Fig.  188. 

DETAILS  OF  SLIDINQ-SLEEVE  VALVES 

A  method  of  avoiding  cams,  and  with  them  all  cam  troubles,  is 
the  use  of  a  sliding  sleeve  in  place  of  a  valve,  slots  in  the  sleeve  cor- 
responding to  the  usual  valve  openings,  both  as  to  area  and  timing. 
The  sleeves  may  be  operated  by  means  of  eccentrics  by  various  lever 
motions,  or  by  a  direct  drive  by  means  of  agear  mounted  on  a  separ- 
ate shaft. 

Qear  ControL  An  example  of  the  application  of  a  worm  and 
gear  for  this  purpose  to  a  French  two-cycle  engine  is  dwwnv  Sa, 


372  GASOLINE  AUTOMOBILES 

Fig.  189,  althougli  there  is  nothing  in  its  construction  which  would 
prevent  its. use  on  the  more  usual  four-cycle  engine. 

In  this  figure,  P  is  the  usual  crankshaft,  Q  the  large  end  of  the 
connecting  rod  A',  while  A  is  the  piston  and  R  the  crankcase,  no 
one  of  these  differing  from  those  in  other  engines.  On  the  tTankshaft 
there  is  a  large  gear  F,  which  drives  a  smaller  gear  E,  located  on  a 
longitudinal  shaft  above  and  outside  of  the  crankcase.  On  this  shaft 
is  located  a  worm  gear  D,  which  meshes  with  a  worm  C  formed  inte- 
gral with  the  sleeve  surrounding  the  piston  B.  Aside  from  this  worm 
gear,  the  sleeve  is  perfectly  cylindrical,  being  open  at  both  ends.  It  is 
placed  outside  of  the  piston,  between  that  and  the  cylinder  walls. 
At  its  upper  end,  it  has  a  number  of  ports,  or  slots,  cut  through  it, 
which  are  correctl\'  located  vertically  to  register,  or  coincide,  with  the 
port  openings  in  the  cylinder  wall  when  the  sleeve  is  rotated.  One 
of  these  is  seen  at  //;  the  exhaust,  while  90  degrees  around  from  it, 
and  hence  invisible  in  this  figure,  is  a  similar  port  for  the  inlet.  As 
the  crankshaft  rotates,  the  side  shaft  carrj-ing  the  worm  is  con- 
strained to  turn  also.  This  turns  the  worm  which  rotates  the  worm 
wheel  on  the  sleeve.  In  this  way,  the  openings  in  the  sleeve  are 
brought  around  tn  the  proper  openings  in  the  cyHnder,  and  the  com- 


GASOLINE  AUTOMOBILES 


273 


actuated  from  a  regular  camshaft — nmning  at  half  the  crankshaft 
speed  and  driven  by  a  silent  chain— by  means  of  a  series  of  eccentrics 
and  connecting  rods.  In  the  figure,  A  is  the  inner  and  longer  sleeve 
and  carries  the  groove  or  projection  C  at  its  lower  end.  The  collar 
actuating  the  sleeve  is  fixed  around  and  into  it.    This  collar  is 


fit.  19a     WiOya-Koiaht  Engii 


Cuds  utA  Vilva 


Sliding  aiccvOB  Replun 


■ttacbed  to  the  eccentric  rod  E,  which  is  driven  by  the  eccentric  shaft 
shown.  TTie  collar  D  performs  a  similar  function  for  the  outer 
sleeve  5. 

At  tlie  upper  ends  of  both  sleeves,  slots  G  are  cut  through. 
These  stots  ate  so  sized  and  located  as  to  be  brought  into  cottwA. 


GASOLINE  AUTOMOBILES 


TABLE  III 
Royal  Automobile  Club's  Committee  Report  on  Knight  Engini 


. .  124  by  130 
.60.8 

..1200r.p.m. 
,  .3805  lb. 
.  .4085  lb. 
..134  hours  IS  n 

!!  Five— 116  min, 

..igmin. 

..54.3 

.  .5  hours  15  tnin 


Molor  horsppower — R.  A.C.  ,  . . 

Bore  and  stroke , 

Minimum  horsepmver  allowed  . 

Speed  on  bench  test 

Car  weight  on  track , 

Car  weight  on  road 

Duration  of  bench  teat 

Penalized  bIodh 

Non-penulizcd  stops 

Light  load  periods , 

Avfirage  horsepower 

Final  bench  teat 

Ponalized  stops 

Light  load  periods 

Average  liorsppower 

Mileage  on  track 

Mileage  on  road. 

Total  lime  on  track 

Average  tratk  speed 

Fuel  per  brake  horsepower  per  hour 


Car  miles  per  gallon ton  Irack.  .  . , 

lOn  road. . . . . 

Ton  miles  per  gallon |On  track  ,  ,. 

\On  rood.  .  .  .. 


22  85 

Sflby  130 

35.3 

1400  r.p.m. 

3332.5  lb. 

3612.51b. 

132  hours  58  a 

Two— ir  min. 
41  min. 
38,83 


45  hours  32  n 
42.4  m.  p.  h. 
First  bench 


.079  pt.  .739  pt. 

.613  lb.  .6681b. 

.599  pi.  .749  pt. 

.541  lb.  -6771b. 

20  67  22,44 

19.48  19.48 

34.94  33-37 

35.97  31.19 


GASOLINE  AUTOMOBILES 


275 


e  surfaces  of  the  valves  are  grooved  at  <7  to  produce  proper  distribu- 
D  of  oil. 

The  Knight  type  of  motor  has  been  adopted  by  a  number  of 
U-known  firms  in  America,  such  as  the  Steams,  Willys,  P.  R.  P., 
jwster,  and  Moline  Companies.  These  engines  are  noted  for 
lir  silent  running  and  for  their  efficiency.  The  Moline-Knight 
■tor  was  subjected  to  a  severe  continuous-run  test  of  337  hours, 
der  the  auspices  of  the  A.  C.  A.  authorities,  in  January,  I9I4. 
iring  this  time  the  motor  developed  an  average  of  38.3  brake  horse- 


Slwves  Which  Replaced  Valve* 


137-Hoiir  Bench  Teet 


.      I  Knuht  E  _   _, 
d  220O  MUa  on  the  Road 

ffer.  During  the  337th  hour  the  throttle  was  opened,  the  motor 
j^eloped  a  higher  speed  and  a  brake  horsepower  of  53.  After  the 
t,  the  motor  parts  showed  no  particular  evidence  of  wear.  The  test 
es  abundant  evidence  of  the  endurance  and  reliability  of  the  sleeve 
ve  tj-pe  of  motor  and  of  the  sterling  qualities  of  the  product  of 
'  American  automobile  manufacturers. 

In  addition  to  the  four-cylinder  forms  just  mentioned,  the 
ight  type-  of  motor  is  also  made  as  a  six,  and,  more  recently,  as 
'-type  eight.  In  these  forms,  the  basic  principle  of  sliding  sleeves 
1  their  method  of  operation  and  timing  is  not  changed. 


276 


GASOLINE  AUTOMOBILES 


Originally',  the  Knight  motor  was  installed  only  in  the  highest- 
class  cars.  The  firms  in  Europe  which  took  it  up  ranked  among 
the  very  first — notably  the  Daimler,  Panhard,  Minerva,  etc. — but 
in  this  country  it  has  made  little  progress  among  the  better  care. 
It  is  now  assuming  the  rank  of  a  low-  and  medium-priced  motor,  being 
available  for  about  $U)(H),  and  as  an  eight,  for  approximately  $2000. 
Timing  the  Knight  Motor.  While  the  connection  between  the 
Knight  motor  sleeves  and  eccentric  rods,  and  between  the  rods  and 
the  eccentric  shaft,  is  more  or  less  permanent,  there  is  the  possibility 
of  the  shaft  being  bent  or  twisted  during  running  or  dismounting. 
The  repair  man  should  know  how  the  motor  is  timed,  in  order  to  cor- 
rect any  faults.  As  will  be  noted 
in  the  timing  diagram  shown  in 
Fig.  192,  this  is  not  radically 
different  from  the  poppet-i-alve 
tj'pe.  The  Inlet  opens  at  6\ 
degrees  past  the  upper  center  and 
closes  45  degrees  past  the  lower 
center,  a  total  opening  of  2t8i 
agrees.    The   exhaust  opens  40 


GASOUNE  AUTOMOBILES 


Inlet  ^ena  Intel  Open  Intel  Cloaea     CompreaaionSlreke, 

Posttignl  Posiliene  F0silian3  Position^ 


Rt- 163.    Varioua  8U(«  in  Cycle  of  Knisht  BUdios-SlMve  Motor 


278  GASOLINE  AUTOMOBILES 

is  beginning  to  open,  the  inner  sleeve  has  reached  the  top  of  its  move- 
ment and  starte<l  down,  while  the  outer  ia  almost  at  the  top.  At  6 
the  exhaust  port  is  fully  ojien,  tlie  slots  register  exactly  with  each 
other  and  with  the  cyHnder  outlet,  both  sleeves  are  traveling  down, 
the  outer  having  reached  and  passed  its  highest  point.  At  7  the 
exhaust  has  just  closed,  the  inner  sleeve  has  reached  its  bottom 
position  and  is  about  to  start  up,  while  the  outer  sleeve  is  close  to  the 
bottom.  The  cycle  of  inlet,  compression,  explosion,  and  exhaust 
has  now  been  completed  and  is  about  to  start  over.  Note  that 
position  7  is  almost  exactly  like  position  /,  but  a  slight  additional 
movement  of  the  sleeves  is  needed  to  produce  the  latter. 

The  eccentric  rods  are  very  similar  to  connecting  rods,  as  will  be 
noted  by  referring  back  to  Fig.  19!.  Here  E  is  the  eccentric  rod 
operating  the  inner  sleeve  C,  while  D  is  the  eccentric  rod  which  oper- 
ates the  outer  sleeve  B.  As  will  be  seen,  these  have  an  upper  end 
exactly  like  a  piston,  or  wtIsI  pin,  except  that  no  bushing  is  provided. 
At  the  lower  end,  it  will  be  noted  that  the  fastening  and  arrangement 
is  just  like  the  big  end  of  a  connecting  rod.  It  should  be  cared  for, 
adjusted,  anti  tiglitcned  in  just  the  same  way  to  get  the  best  results. 


DETAILS  OF  ROTATING  VALVES 


GASOLINE  AUTOMOBILES 


Roberta  Rotary  Valve,    A  motor — a  two-cycle  motor,  by  the 
way — which  has  been  very  successful  in  motor-boat  and  aeroplane 


Fic.  194,     Ri 


work,  although  not  much  used  for  motor  cars,  is  the  Roberts,  shown 
in  Fig.  194,  with  the  valve  in  Fig,  195.  This  valve  is  for  the  inlet 
ports  only  and  is  located  inside  the  crankcase,  while  the  cylinders 


a 


exhaust  freely  into  the  open  air,  the  exhaust  issuing  directly  from 
the  cylinders. 

EXHAUST  SYSTEM 
Inqmrtance  of  Handling  Exhaust  Oases  Properly.  In  all  that 
has  been  said  previously  on  the  subject  of  valves  no  mention  has  been 
made  of  a  specific  form  of  valve,  everything  applying  equally  to  the 
inlet  or  the  exhaust  type.  Under  the  subject  of  carburetors,  the  inlet 
manifold  has  been  considered  in  detail.  So  far,  nothing  has  been  said 
of  the  exhaust  gases  and  the  method  of  handling  them.  Generally 
speaking,  the  matter  of  handling  exhaust  gases  in  the  past  has  been 
done  with  the  smallest  possible  amount  of  time,  trouble,  and  thoii^ht. 
They  had  to  be  gotten  rid  of,  so  it  was  done  as  easily  and  ^vucVi:]  «% 


GASOLINE   AUTOMOBILES 


ls  engines  got  larger  and  larger,  and  as  speeds  increased, 
there  was  more  and  more  gas  to  handle.  The  growing  cTy  for  a  quiet 
or  a  noiseless  car  necessitated  giving  the  problem  more  thought,  for 
the  simple  appHcatioii  of  a  muffler  did  not  entirely  eliminate  the  noise. 
As  fuels  grew  heavier,  heat  was  required  to  assist  in  tlie  process  of 
vaporising.  In  order  to  apply  heat,  many  designers  began  to  see 
possible  uses  for  some  of  the  gas  pouring  out  at  the  rear  end  of  the  car. 
Todaj',  the  handling  of  tlie  exhaust  gases  is  probably  being  given  as 
much  thought  as  any  part  or  unit  on  the  entire  car. 

Forms  of  Exhaust   Manifolds.    Ordinarily  the  exhaust  gases 
emerge  from  tlie  cylinders  into  the  exhaust  manifold.    This  is  gen- 


GASOLINE  AUTOMOBILES  281 

has  the  outude  valves,  so  the  exhaust  manifold  is  located  there.  It  is 
a  typical  cast-iron  manifold,  differing  from  the  ordinary  manifold 
only  in  having  the  outlet  at  the  center  instead  of  the  rear  end.  Six 
bolts  hold  it  in  place;  four  on  the  upper  edge,  and  two  on  the  lower. 
Its  interior  structure  is  evidently  the  same  throughout,  and  no  special 


provision  has  been  made  for  reducing  gas  friction.    It  has  no  attach- 
ments of  any  kind. 

Many  exhaust  manifolds  have  been  cast  integral  with  the  cylin- 
der block;  this  method  is  quite  popular  among  small  car  makers,  as  it 
is  used  as  mudi  to  save  the  expense  of  machining  and  fittmf^  uv&  \iq 


282 


GASOLINE  AUTOMOBILES 


reduce  the  weight  and  number  of  parts  as  for  any  other  reasons. 
In  the  larger  sizes  it  probably  never  will  become  popular,  because  of 
the  difficult  core  work  in  the  foundry  which  makes  cylinder-casting 
cost  prohibitive,  and  thus  more  than  offsets  any  other  saving. 

A  number  of  manifolds  have  been  cast  with  cooling  fins,  or  flanges, 
on  the  outside,  the  effect  being  to  reduce  the  exhaust  heat  immediately 
by  dissipatiun ;  a  secondary  idea  is  that  of  making  the  casting  stilfer 
and  stronger  and  less  liable  to  loss  by  breakage.     A  flanged  manifold 


GASOLINE  AUTOMOBILES 


284  GASOLINE  AUTOMOBILES  " 

of  gas  to  be  handled,  the  speed  at  which  it  had  to  be  handled,  and  the 
necessity  for  silence  called  for  a  separate  exhausting  system  for  each 
group  of  cylinders.  These  were  problema,  aside  from  the  fact  that  it 
was  more  simple  structurally  to  handle  the  exhaust  in  two  manifolds. 
A  double-manifold  construction  is  shown  in  the  Cadillac,  Fig,  198, 
which  is  a  view  of  the  rear  end  of  the  engine.  The  two  manifolds 
for  the  two  sides  can  be  seen  readily;  also  the  two  separate  exhaust 
pipes,  wrapped  with  asbestos  where  they  pass  the  dash  and  other 
wooden  parts.  A  further  view  of  this  car  is  shown  in  Fig,  199,  the 
chassis  from  above,  in  which  the  two  separate  systems  can  be  fol- 
lowed back  to  the  mufflers  Just  forward  of  the  rear  axle  on  either  aide. 
Muffler.  The  purpose  of  the  muffler  is  to  reduce  the  pressure  of 
the  ftascs  by  expansion  to  a  point  where  they  will  emerge  into  the 
atmosphere  witiiout  noise.  This  is  generally  done  by  providing  a 
numlxT  of  concentric  chambers;  the  gas  is  allowed  to  expand  from  the 
first  pjiKSJijre  into  tlie  much  larger  second  one,  then  into  the  still  lai^r 
third  one,  and  so  on,  to  the  final  and  largest  passage,  which  is  con- 
nected to  the  pijje  leading  out  into  the  atmosphere.  This  is  not  as 
simple  as  it  sounds,  for,  if  it  is  not  well  and  wisely  done,  there  will  be 
back  pressure  which  will  reduce  the  power  and  speed  of  the  engine, 


GASOLINE  AUTOMOBILES 


rj(. 


. ' 


— ) 


t         *         i 


28S  GASOLINE  AUTOMOBILES    . 

t.vpe.  Cone-iihaped  baffles  whicli  force  the  gases  to  expand  and  then 
pass  through  ven'  small  apertures  and  expand  again  form  the  ba^  of 
E.  This  is  the  si>-t-alled  ejector  t  j-pe,  the  passage  of  the  gases  from  the 
large  to  the  small  end  of  the  various  cones  being  supposed  to  create 
a  suction  behind  it  which  draws  the  gas  out  from  the  exhaust  pipe 
continuously. 

Muffler  Troubles.  When  the  engine  mjsteriously  loses  power, 
it  is  well  to  lo<jk  at  the  muffler.  A  dirty  muffler  fiUed  up  with  oU  and 
carbon,  which  results  from  the  use  of  too  much  oil  in  the  motor,  will 
choke  up  the  passages  so  that  considerable  back  pressure  is  created. 
When  this  is  suspetteil,  tap  the  muffler  aU  over  hghtly  with  a  wooden 
mallet,  and  the  exliaust  gases  1^ill  blow  the  sooty  accumulations  out. 

Cut-Outs.  Formerly,  the  majority  of  cars  were  equipped  with 
muffler  cut-outs,  liy  pressing  the  foot  on  the  button  operating  the 
cut-out,  the  engine  was  allowed  to  exhaust  directly  into  the  atmos- 
phere, cutting  out  the  muffler.  It  sensed  as  a  warning  signal ;  it  gave 
a  good  means  of  checking  up  the  firing  of  the  various  cylinders;  and 
several  years  ago,  it  nas  supposed  to  give  greater  power.  Since  its 
use  was  overdone,  many  cilies  and  state;*  prohibited  such  an  arrange- 


GASOLINE  AUTOMOBILES 


287 


Water-Jacketing.  The  first  essential  in  water-cooling  a  motor 
is  to  provide  the  cylinders  with  water  jackets,  through  which  the 
cooling  water  is  circulated  in  contact  with  the  outside  of  the  walls 
within  which  the  heat  is  liberated. 

Water  jackets  are  of  two  tj^pes,  integral  and  built-up.  The  latter 
3\"5tem  of  construction,  though  adding  to  complication  and  conducive 
to  leakage,  permits  of  lighter  construction,  besides  diminishing  the 
likelihood  of  hidden  flaws  in  the  cylinder  castings,  which,  with  cored 
jackets,  are  not  likely  to  reveal  themselves  until  they  cause  a  break- 
down, perhaps  after  the  engine  has  been  long  in  use. 

Integral  Jackets.  With  integral  jackets,  the  usual  system  is  to 
form  the  jackets  by  cores,  in  the  founding,  so  that  there  are  no  open- 


Els.201.     Detailed  View  of  Csdillu  CrUnder  Chwii 

ings  in  the  jackets  except  those  for  removing  the  core  sand  and  wires 
and  for  connecting  the  pipes  of  tlie  circulating  system.  In  many  of 
the  best  examples  of  motor  design,  howe\er,  the  core  openings  are 
left  very  large  but  with  plane  faces,  and  are  closed  by  screwcd-on  or 
clamped-on  plates,  thus  making  tlie  construction  practically  a 
compromise  between  the  completely  integral  and  the  completely 
built-on  jackets. 

For  example,  in  such  modem  construction  as  that  shown  in 
Fig.  2,  a  large  plate  will  be  noted  on  the  ends  of  the  cylinders.  This 
covers  a  tremendous  core  hole,  by  the  use  of  which  the  internal 
construction  of  the  water  jackets  is  made  practically  perfect  in  the 
foundry.  This  also  allows  easy  inspection  and  cleaning,  the  removal 
of  the  two  end  plates  enabling  a  person  to  see  right  through  tbe  ^».\JW 


288  GASOLINE  AUTOMOBILES 

jacket  from  end  to  end.  This  latter-day  construction  overcomes  all 
objections  previously  raised  against  troubles  with  complicated  water- 
jacket  cores.  A  detail  of  this  cylinder  block,  showing  clearly  the 
arrangement  of  the  cikI  plates,  the  water  passages  around  the  cjlin- 
der  bores,  and  other  points,  is  presented  in  Fig.  201.  The  designers 
of  large  block  castings  for  cylinders  were  forced  to  provide  for  easy 
inspection  of  this  kind  for  self-protection,  although  in  this  connection, 
it  is  no  more  than  fair  to  state  that  foundry  men  have  made  just  as 
rapid  advances  in  the  art  of  casting  automobile-engine  cylinders  and 
other  complicated  parts  as  the  designers  of  machines  have  made  in 
every  other  wa,\\ 

Hmlt-On  Jackets.  There  are  a  number  of  forms  of  built-on 
water  jackets,  but  few  of  these  are  in  use  at  present.  The  best  of 
these  was  the  old  Cadillac  jacket,  a  cyhndrical  one-piece  member  with 
a  junk  ring,  top  and  bottom,  to  hold  tightly  against  water  leakage. 
The  form  mure  often  used  is  the  applied  plate,  or  sheet,  which  must  be 
held  b\-  s<Te\vs,  llanges.  or  clamps.  As  these  are  not  really  success- 
ful in  holding  the  water  contuiuously,  particularly  against  the  com- 
bination of  hot  water,  internal  pressure,  twisting,  and  nicking  action 
which  ojnios  from  tra\eling  over  bad  roads  at  high  speeds,  they  are 


GASOUNE  AUTOMOBILES  289 

obtain  sudi  a  combination  at  a  reasonable  cost.  So  far,  however, 
it  has  been  restricted  to  racing  cars,  in  which  the  lightest  possible 
weight  is  obtained  regardless  of  cost.  In  a  car  to  sell  at  an  ordinary 
price,  the  cost  might  be  prohibitive. 

Radiators  and  Piping.  It  has  often  l>een  pointed  out  that  all 
cooling  of  automobile  engines  is,  in  realit;-,  air  cooling;  the  water- 
cooled  motor  is  simply  one  in  which  the  heat  units  to  be  disposed 


Studeluker  Cut 


of  are  coifveyed  from  the  cylinders  to  the  radiator  by  the  circulating 
water,  to  be  dissipated  in  the  air  that  passes  through  it,  instead  of 
directly  lost  in  air  passing  over  thin  flanges  cast  on  the  cylinders. 
A  water-cooling  system  therefore  constitutes  a  sort  of  indirect-air 
cooling.  This  being  the  case,  the  chief  justification  for  water  cooling 
consists  in  the  margin  it  allows  for  much  greater  cooling  areas  in 
contact  with  air  than  it  is  possible  to  provide  by  mere  extensions  of 
the  cylinder  surfaces  themselves. 


290 


GASOLINE  AUTOMOBILES 


A  tj'pical  pleaRureH?ar  radiator  of  the  tubular  type  is  shown  m 
Fig.  202.  As  will  he  nnted,  the  flanges  have  a  continuous  horizontal 
appearance,  but  the  vertical  tubes  which  carry  the  water  can  be  seen 
in  the  background.  These  actually  carry  the  water;  the  horizontal 
flanges  simply  serve  as  a  heat-radiating  surface.  This  type  is  rapidly 
increasing  in  popularity  for  pleasure  cars  of  medium  and  low  price, 
at  the  expense  of  all  others. 

The  total  cooling  area  of  the  radiators  employed  io  automobiles 
will  range  all  tlie  way  from  ten  to  ninety  square  feet;  the  latter 


Secliai  of  Filler 


GASOUNE  AUTOMOBILES  291 

a  motor  that  may  have  run  for  months  without  any  cooling  trouble 
whatever  in  level  eountry  will  often  hoil  all  the  water  out  of  the 
cooling  system  within  a  few  minutes. 

Tppei  of  Cell*.  In  the  cellular,  or  honeycomb,  radiator,  there  are 
three  forms  of  tubing  in  general  use.  These  forms  are:  the  square, 
with  its  flat  sides  set  horizontally  and  vertically;  the  round,  with  the 
tubes  staggered  so  as  to  make  the  number  as  large  as  possible;  and 
the  hexagon,  which  is  also  set  staggered  so  as  to  use  the  maximum 
number.    The  square  and  hexagon  are  more  used  on  pleasure  cars. 


Fig.  204.    Beoault  Foi 


while  the  round  form  has  been  used  on  higher-priced  motor  trucks. 
A  modification  of  the  round-tube  form  is  found  in  the  radiator  which 
utilizes  the  plain  cx)pi>er  tubes,  bunched  and  fitted  into  a  header,  or 
water  tank,  at  the  end,  but  which  are  not  formed  into  a  composite 
unit.    This  is  used  on  both  pleasure  cars  and  trucks. 

Types  of  Tubes.  In  the  tubular  form,  there  are  two  well-known 
types:  the  round  vertical  tube  with  spiral  fin,  or  flange,  welded  or 
sweated  on;  and  the  so-called  tube-and-plate  construction,  shown  in 
Fig.  202,  in  which  a  set  of  horizontal  plates  is  pierced  with  a.  nucoAtet 


im 


GASOLINE  AUTOMOBILES 


of  holes,  tubes  set  into  these,  and  the  whole  dip-soldered  into  a  unit. 
The  former  t.Npe  is  gaining  rapidly  for  truek  use  on  account  of  its 
freedom  from  leakage  under  the  severe  racking  conditions  of  truck 
use.  An  example  of  this  t>pe  is  to  be  found  in  Fig.  203,  which  shows 
a.  welded  tubular  radiator.  It  is  of  interest  to  note  that  the  welded 
tjpe  replacetl  a  soldered  honeycomb  unit  of  the  highest  quality  which 
could  not  be  kept  water  tight  in  war  service. 

Modifications  of  Cellular  and  Tubular  Fonns.    In  addition  to  tlie 
types  shown  in  Figs.  202  and  203,  there  are  a  mmiber  of  forms  which 


GASOLINE  AtlTOMOBILES  293 

Another  modification  abng  somewhat  simUar  linra,  whidi  isused 
For  a  truck,  is  that  shown  in  Fig.  205.  This  fonn  consists  of  an  upper 
tank,  a  small  lower  tank  with  the  outlet,  and  a  connecting  group  of 
xpper  tubes.  It  is  made  in  the  form  of  a  circle  of  the  largest  possible 
diameter  the  tube  structure  will  allow  and  of  a  width  equal  to  the 
depth  of  the  bank  of  tubes.  The  fan  is  placed  in  its  immediate 
:;ent«r.  By  placing  the  radiator  at  the  rear  end  of  the  engine,  the 
fan  can  be  driven  directly  from  the  crankshaft  or  the  flywheel,  which 
^ves  the  fan  a  higher  speed.  The  unusual  size  and  high  speed  of  the 
-'an  circulates  an  unusual  amount  of  air  around  the  bare  copper  tubes. 
I^opper  is  the  best  radiator  of  heat  known  except  silver.  On  a  truck, 
'.he  position  of  the  radiator  at  the  back  of  the  engine  is  held  to  be 
I  big  advantage,  because  the 
;ntire  cooling  system  is  protected 
rora  the  frequent  and  unavoid- 
ible  collisions  of  truck  service. 

The  piping  of  automobile 
»oling  systems  in  a  great  many 
ars  is  made  too  small  to  afford 
-'ree  circulation,  and  this  mistake 
D  design,  common  in  the  earlier 
lays  of  automobile  engineering, 
3  one  that  cannot  be  too  carefully 

tvoided.  n*.  20e,     Oev  Type  of  WMw  Pump  ol 

,  .  ^  Very  Simple  Coxutruetioo 

In  the  expenence   of  most 
lutomobile  designers,  the  most  satisfactory  method  of  connecting 
ip  the  piping  of  a  circulating  system  is  found  in  the  use  of  ordinary 
steam  hose,  clamped  around  the  ends  of  the  pipe  by  small  metal 
(traps. 

The  use  of  steam  hose  for  practically  the  entire  piping  system 
s  considered  an  improvement  over  the  short  hose  connection  by  a 
few  designers.  It  does  away  with  metal  piping  altogether  except  as 
it  extends  from  the  radiator  and  water  jackets  for  the  attachment  of 
the  hose. 

Circulation.  An  unobstructed  and  vigorous  circulation  of  the 
rater  in  a  cooling  system  is  a  great  factor  in  reducing  the  size  of 
radiator  required  and  in  preventing  overheating  and  boiling  away 
)f  the  water. 


294  GASOLINE  AUTOMOBILES 

Pumps.  The  usual  method  of  circulating  the  cooling  water  !s 
to  use  one  type  or  another  of  small  pumps,  driven  by  suitable  gearing 
from  the  engine  itself. 

Gear  pumpsare  often  used  for  thiapurpose  because  of  their  extreme 
simplicity,  but  it  is  difficult  to  make  them  large  enough  to  handh. 
as  great  volumes  of  water  as  most  designers  now  regard  desirabW 

A  good  example  of  the  gear  form  of  watur  pump  is  shown  'm 
Fig.  206.  This  is  simply  a.  pair  of  gears  which  mesh  rather  closely^ 
the  movement  of  the  flat  side  of  the  teeth  carries  or  forces  the  watet 


GASt^UNE  AUTOMOBILES 


295 


simple  multi-bladed  "impellers"  revolvioj^  with  close  clearances  in  a 
housing. 

One  advantage  of  the  centrifugal  pump  is  that  if  any  small 
object,  such  as  a  stick  or  pebhie,  should  by  any  chance  get  into  the 
circulating  system — though  strainers  always  should  be  provided  to 
prevent  this  contingency — no  serious  harm  is  likely  to  result,  whereas 
with  a  gear  pump  breakage  is  almost  certain  to  ensue. 

The  construction  of  the  centrifugal  form  can  be  seen  in  Fig.  207. 
This  is  not  as  clear  as  it  might  be  because  the  impeller  is  sectioned  at 


Coolini  u  Used  an  Overlnod  Can 


the  point  where  the  water  chamber  is  largest;  in  short,  at  the  water- 
outlet  space.  The  impeller  fits  the  casing  very  closely  except  at 
the  water  outlet  where  the  water  is  thrown  off  by  the  centrifugal 
force  generated  in  rotation.  The  centrifugal  form  of  pump  is  also 
fairly  well  illustrated  in  Fig.  210,  where  it  will  be  noted  that  two  of 
them  are  used  on  the  two  ends  of  the  upper  shaft. 

Chiefly  in  motor-boat  motors  of  the  two-cycle  types,  recipro- 
cating plunger  pumps  are  used  to  circulate  the  cooling  water.  The 
volimie  of  water  handled  by  pumps  of  this  type,  of  dimensions  that 
can  be  conveniently  employed,  is  not  very  large,  however,  and  it  is 


296 


GASOLINE  AUTOMOBILES 


only  the  fact  that  the  water  is  not  Fe-used  and  is,  therefore,  cooler 
and  of  a  consequently  greater  effectiveness  that  makes  possible  the 
use  of  plunger  pumps  in  motor  boats. 

Thermosipkon.  Circulation  of  the  cooling  water  by  the  thermo- 
siphon  action,  owing  to  the  heated  water  in  the  jackets  rising  and  the 
cooled  water  in  the  radiator  descending,  is  the  practice  of  an  increas- 
ing number  of  designers,  and  has  been  demonstrated  to  be  very 
effective  with  liberal  jacket  spaces  and  large-diameter  piping. 

The  pioneer,  and  still  the  most  prominent  exponent,  of  thermo- 
siphon  cooling  is  the  Ilenault  Company,  of  France.  A  t^Tiical 
Renault  nmtor-inid- radiator  combination  with  thermosiphon  cir- 
culation is  illustrated  in 
Fig.  204. 

A  better  example  of 
the  thermosiphon  sys- 
tem, that  is,  a  drawing 
which  shows  it  much 
better  is  Fig.  208.  In 
this  the  large  open  pipes 
with    few    bends,*  and 


GASOUNE  AUTOMOBILES 


297 


certain  figure  at  which  the  thermostat  is  set,  it  comes  into  action  and 
cuts  off  the  flow  of  water  from  the  radiator  to  the  pump.  The  result 
is  that  the  pump  can  circulate  only  that  part  which  comes  through 
the  very  small  pipe  to  the  inlet  manifold  and  carburetor  and  from 
there  back  to  the  pimip.  This  continues  until  the  water  becomes 
heated;  the  raising  of  the  temperature  oj^rat-"  the  thermostat  whicli 
opens  the  valve,  and  the  s>steni  n  agum  (.■()m[ilete.    In  the  upper 


right-hand  part  of  this  figure,  the  circulating  system  of  one  block  of 
cylinders  is  shown  in  outline. 

The  method  of  controlling  the  temperature  of  the  engine  with 
an  automatic  check  valve  is  receiving  much  attention;  there  is  even 
talk  of  extending  the  same  system  of  control  to  the  exhaust  gases  and 
all  sources  of  heat,  interconnecting  them  with  the  fuel  vaporizer  so 
as  to  vaporize  the  maximum  amount  of  fuel  in  the  minimum  time  with 
the  least  heat  loss.  The  tl\ermostat  and  pump  combination  used  on 
the  Packard  twelve-cylinder  motor  is  shown  in  Fig.  210,  in  which  it 
will  be  seen  that  two  pumps  are  placed  on  the  pump  shaft,  one  at 


3I» 


GASOLINE  AUTOMOBILES 


each  end  so  that  the  thrust  of  each  one  balances  the  other.  In  the 
Cadillac,  the  two  cyhnder  groups  are  separate,  each  having  all  the 
units  shown  in  Fig.  209  except  t^e  radiator.  Id  both  the  Cadillac 
and  Packard  systems,  the  thermostat  is  placed  at  the  bottom  of  the 
system.  It  has  been  advocated  by  engineers  for  other  companies 
that  this  would  do  the  most  good  if  placed  at  the  top  of  the  system. 

The  value  of  a  thermostat  may  be  gained  from  these  figures. 
One  particular  make  of  thermostat,  as  used  on  a  popular  make  of  car, 
was  tested  out  with  the  following  results:  Without  it,  the  car  did 
14)  milt»  on  a  gaUon  of  fuel  at  15  nLpJi.  and  13}  miles  at  30  m.pJi. 
At  the  same  speeds  and  with  the  thomostat  set  at  160  degrees, 
the  same  car  under  the  same  circumstances  did  16}  miles  at 
almost  15  m.p.h.  With  everything  the  same  but  with  the  device  set 
to  work  at  180  degrees,  the  car  did  19}  and  16}  miles,  rapectivdy. 
The  gain  at  the  lowest  speed  of  15  miles  an  hour  from  14}  to  16}  and 
then  to  19}  miles  per  gallon  represents  gains  of  almost  14  and  3ft 
per  cent  in  economy. 

Fans.  In  the  earlier  days  of  autconobile  deigning  it  waa 
deemed  sufhcient  to  secure  drculation  of  air  through  the  radiaton 
by  the  movement  of  the  car  alone.    This  was  soon  found  inadequate 


GASOLINE  AUTOMOBILES  299 

must  pass  through  the  center  where  the  fan  is  located.  This  is  but 
another  way  of  saying  that  all  air  must  pass  through  at  a  high 
velocity,  which  insures  eflSciency.  This  plan  fulfills  one  requirement 
of  air  cooling,  that  is,  the  large  quantity  of  air  which  must  be  used. 

Where  this  system  is  used  now,  the  entire  engine  in  front  of  the 
fan  is  made  air  tight.  The  hood,  which  has  no  openings  anywhere,  is 
set  into  .carefully  fitted  rubber  strips  to  cut  off  any  possible  leakage. 
The  same  precautions  of  drawing  all  the  air  through  the  radiator, 
and  through  that  alone,  are  observed  elsewhere.  While  this  method  is 
eflFective,  it  is  a  disadvantage  in  another  way,  for  some  direct  cooling 
is  effected  through  the  cylinder  walls,  exhaust  pipes,  etc.,  in  the 
ordinary  system  by  the  cold  air  passing  over  the  radiator,  particularly 
the  air  which  comes  in  from  around  the  hood  top  and  sides. 

Anti-Freezing  Solutions.  In  using  automobiles  in  very  cold 
climates  during  the  winter  months,  there  is  great  danger  of  the  water 
in  the  cooling  system  freezing  when  the  car  is  standing  still,  or  even 
with  the  motor  running  slowly  if  the  temperature  is  very  low.  The 
result  of  such  freezing  is  almost  certain  injury  to  the  cylinders, 
through  cracking  of  the  water  jackets,  as  well  as  the  probability  of 
bursting  out  radiator  seams,  with  consequent  leakage. 

To  avoid  these  difficulties  it  is  not  uncommon  to  use,  instead 
of  piu^  water,  one  kind  or  another  of  anti-freezing  solution,  usually 
compounded  by  the  mixture  of  some  chemical  with  water  to  lower 
its  freezing  point.  Thus,  glycerine  or  alcohol  mixed  with  water  will 
keep  it  from  freezing  at  all  ordinary  winter  temperatures.  Glycer- 
ine is  somewhat  objected  to  because  of  its  sticky,  gummy  nature,  and' 
also  because  of  its  deleterious  effects  upon  the  rubber  hose  of  the 
piping  system.  Alcohol,  if  not  replenished  from  time  to  time,  will 
evaporate  out  of  the  water  and  thus  permit  it  to  freeze,  or,  if  mixed  in 
too  great  a  quantity,  it  may  introduce  a  fire  risk  otherwise  avoidable. 

A  much  favored  anti-freezing  solution  consists  of  calcium 
diloride  dissolved  in  water,  in  a  quantity  proportioned  to  the  tem- 
peratures that  it  is  desired  to  guard  against. 

All  anti-freezing  solutions  are  more  or  less  objectionable  in  that 
they  are  more  likely  than  pure  water  to  corrode  and  clog  up  the  cir- 
culating system,  and  there  is  no  doubt  that  the  elimination  of  the 
necessity  for  them  by  the  substitution  of  air  cooling  for  water 
cooling  will  mark  a  great  advance  in  automobile  development. 


300 


GASOLINE  AUTOMOBILES 


AIR  COOLINO 

Though  successfully'  employed  in  on6  or  two  automobiles  and 
remarkably  tle\'eloped  in  some  of  its  applications  to  aviation  motors, 
air  cooling  is  not  considered  by  most  engineers  to  be  successfully 
a|>pIicabIo  to  the  average  automobile.  That  it  will  become  more 
practical  in  the  future,  however,  is  the  opinion  of  many. 

I'nfortunatcly,  this  is  an  instance  where  the  better  and. simpler 
method  does  not  meet  with  popular  approval,  that  is,  the  cooling 


GASOLINE  AUTOMOBILES  301 

Air  Jackets.  Several  of  the  most  practical  examples  of  air- 
cooled  motors  in  aviation  construction  are  those  which  have,  in 
addition  to  the  flanges,  or  fins,  on  the  cylinders,  air  jackets  to  concen- 
trate the  drafts  of  air  that  effect  the  cooling. 

Blowers  and  Fans.  The  most  successful  air  cooling  has  been 
accomplished  by  types  of  blowers  capable  of  inducing  much  more 
vigorous  air  currents  than  are  drawn  through  the  radiators  of  water- 
cooled  automobiles  by  the  types  of  fans  commonly  used  in  power 
plants  of  that  character. 

In  the  Franklin,  the  most  successful  air-cooled  automobile 
motor,  a  side  view  of  which  can  be  seen  in  Fig.  211,  the  cooling  is  a 
sort  of  combination  of  the  flange  and  the  blower  method.  The  fins 
are  vertical  and  radial,  with  a  close-fitting  hood  connected  to  an  air- 
tight pan.  At  the  only  opening  in  this  hood,  which  is  at  the  rear  end, 
is  placed  the  fan  (on  the  fl^nvheel).  This  draws  the  air  past  the 
cylinder  walls,  where  it  is  needed. 

Infernal  Cooling  and  Scavenging.  Perhaps  more  promising  as 
a  road  to  final  and  universal  use  of  air  cooling  are  the  systems  of 
pumping  air  through  the  interiors,  instead  of  blowing  it  over  the 
exteriors,  of  the  cylinders.  Such  internal  cooling,  in  addition  to 
directing  the  maximum  cooling  effect  where  it  is  most  needed  oh 
the  oil-coated  surfaces  that  are  exposed  to  the  heat  of  combustion, 
has  the  further  advantage  that  it  may  be  made  to  scavenge  out  all 
residual  exhaust  gases,  which,  besides  helping  to  accumulate  heat, 
also  act  so  detrimentally  upon  the  functioning  of  ordinary  motors. 
This  is  a  direct  result  of  the  admixture  of  retained  exhaust  gases 
with  incoming  fresh  charges. 

Methods  of  internal  cooling  and  scavenging  that  appear  of 
.  definite  promise  are  those  proposed  in  various  recent  schemes  for 
pumping  air  first  into  the  crankcase — either  by  using  the  under  side 
of  the  piston  as  a  pump,  as  in  common  two-cycle  constructions,  or 
by  applying  special  pumps  to  the  crankcase  for  this  particular  pur- 
pose— then  into  the  cylinders  by  means  of  by-passes,  with  the  result 
that  it  exerts  a  positive  cooling  effect  inside  the  cylinder. 

In  England,  some  interesting  experiments  have  been  made  on  a 
theory  of  internal  cooling  in  which  water  is  introduced  into  the 
cylinders  in  the  form  of  a  spray,  at  certain  points  in  the  cycle.  This 
is  said  to  add  power  in  addition  to  helping  the  cooling. 


302  GASOLINE  AUTOMOBILES 

COOLINQ  TROUBLES  AND  ADJUSTMENTS 
Cleaning.  It  ia  highly  important  that  the  cooling  sj'atem  be 
entirely  cleaned  out  at  least  once,  and  preferably  twice,  a  year.  What 
this  is  done,  the  water  jackets  and  radiator  should  be  flushed  out  witi 
a  strong  current  of  water,  preferably  a  hot  soda  solution.  Tliia  should 
be  forced  through  in  a  direction  opposite  to  the  usual  course  of  thft 
water.  Thus,  a  hose  can  be  put  in  the  radiator  filler  cap  and  city 
pressure  applied  to  force  the  water  through ;  in  this  radiator,  it  will  be 
made  to  go  from  bottom  to  fop  instead  of  the  usual  top  to  bottom. 
If  this  method,  which  is  the  usual  and  easy  one,  does  not  remove  aDi 
dirt,  sediment,  and  foreign  matter,  the  radiator  can  be  removed  and 
boiled,  or  at  least  submerged,  in  a  strong  soda  solution  which  wiH, 
clean  it  out  thoroughly.  The  radiator  is  the  most  important  member 
of  the  system. 

Replacements.  When  thia  is  done,  it  is  advisable  also  to  look 
over  all  hose  and  hose  connections.  Many  times  the  liose  will  have 
become  worn  or  frayed  through  and  cut  or  otherwise  damaged  fron 
the  outside,  or  the  water  may  have  attacked  it  from  the  ttiside,  par-- 
ticularly  if  it  has  been  through  a  winter  when  an  anti-freezing 
solution  was  used.     It  is  well,  when  cleaning  the  system,  to  replace  aU 


GASOUNE  AUTOMOBILES  303 

others  need  the  application  of  a  pointed  tool  and  hammer  to  tmn 
it.  In  the  latter  case,  do  this  very  carefuity  so  as  not  to  chip  off 
any  metal.  OccasionaUy,  the  fan  bearings  need  adjustment  or  lubri- 
cation. When  they  are  of  the  plain  type,  a  grease  cup  is  generally 
provided,  and  after  the  engine  is  stopped,  a  couple  of  turns  of  thia 
will  be  sufficient.  If  of  the  ball  or  roller  type,  they  will  be  packed  in 
grease,  and  if  they  show  signs  of  running  dry,  the  fan  should  be  taken 
apart  and  the  grease  renewed.  Use  a  good  grade  of  cup  grease  for 
this  purpose,  not  a  hard  grease. 

Adjusting  Puiiq)5.    Generally,  the  pump  is  made  so  as  to  need  no 
adjustment.    However,  a  leak  may  occur  at  one  of  the  packing  nuts. 


To  remedy  it,  tighten  the  nut  as  far  as  possible,  but  if  this  does  no 
good,  remove  the  nut  and  add  packing  under  it.  Special  packing  is 
provided  for  this  purpose,  but  if  no  other  is  available,  a  thick  heavy 
piece  of  string  can  be  well  coated  with  graphite  or  a  graphite  grease 
and  wound  on  as  packing.  In  putting  on  packing  of  this  kind,  it 
should  be  wound  on  right_handed,  or  in  the  same  direction  as  the  pack- 
ing nut  turns  to  tighten.  Otherwise,  tightening  the  nut  will  loosen 
the  packing. 


304  Gasoline  automobiles 

The  Ford  motor  circulation  is  of  the  tliermosiphon  order,  but 
often,  for  one  reason  or  another,  it  does  not  do  well,  so  the  motor  con- 
tinues to  heat,  although  everj'thing  appears  in  good  condition,  fan 
belt  tight,  etc.  For  snch  cases,  an  additional  means  of  circulating 
the  water  is  needed.  There  are  several  devices  on  the  market,  one 
consisting  of  a  form  of  screw  set  into  the  water  pipe  with  the  idea  of 
stabilizing  the  flow  of  water.  Another,  Pig.  212,  uses  the  force  of  the 
exhaust  gas  by-j^asaed  through  a  small  special  pipe  into  a  nozzle 
of  the  ejector  type  placed  in  the  water  inlet  to  cylinders  to  make 
the  water  flow  more  rapidly  and  evenly.  It  is  said  that  this  uses  but 
3  per  cent  of  the  exhaust  gas  and  that  it  is  designed  to  keep  the 
water  sj'stem  working  at  195  degrees,  which  is  a  very  efficient  point, 
more  power  being  developed  at  temperatures  approaching  the  boiling 
point  than  at  low  temperature.  In  addition  to  improving  the  water- 
circulating  system,  this  device  is  said  to  eliminate  carbon  formation 
and  save  20  per  cent  of  the  fuel  and  oil. 

In  general,  the  cooling  system  is  an  easy  one  to  take  care  of  and 
repair  because  such  a  large  part  of  its  units  and  components  are  fool- 
proof. Moreover,  it  is  a  system  which  gives  visual  and  other  evi- 
dences of  derangement. 


GASOLINE  AUTOMOBILES  305 

up,  which  can  be  checked  by  disconnecting,  or  else  the  circulating 
pump  is  not  working  properly.  All  modern  engines  are  so  propor- 
tioned that,  in  this  event,  the  water  continues  to  circulate  by  thermo- 
siphon  action.    Taking  off  the  pump  will  verify  this. 

LUBRICATION  SYSTEM 

MOTOR  LUBRICATION 

When  the  lubrication  system  is  referred  to,  that  of  the  motor  is 
generally  meant.  Motor  lubrication  is  of  the  highest  importance; 
for  the  motor  must  have  efficient  and  continuous  lubrication  to  run 
properly.  Taken  in  its  broadest  sense,  however,  the  title  should  refer 
to  the  entire  lubricating  means  of  the  car;  that  is  the  way  it  will  be 
handled  here.  The  other  units  and  parts  of  the  car  may  not  need  as 
efficient  or  as  continuous  means  of  lubrication  as  the  engine,  and  the 
presence  or  lack  of  lubricant  is  not  so  tremendously  important;  but  all 
of  it  is  of  value  and  influence  in  the  operation  of  the  car,  and  should 
be  well  known. 

Interior  and  Exterior  Demands.  The  engine  of  a  motor  car 
requires  two  distinct  kinds  of  lubrication.  The  interior  parts,  which 
are  subjected  to  the  greatest  heat,  rotate  or  slide  at  the  highest 
rate  of  speed,  and  generally  do  the  greatest  amount  of  work,  must 
have  what  amounts  to  a  continuous  stream  of  good  lubricant.  With 
the  exterior  parts,  which  do  not  rotate  so  fast,  do  less  work,  are  not 
subjected  to  much  heating,  and  will  be  kept  cool  by  the  atmosphere, 
there  is  no  need  for  this  continuous  stream,  nor  for  such  a  quantity 
or  high  quality  of  lubricant. 

The  exterior  and  interior  systems  must  be  considered  sepa- 
rately. With  reference  to  the  internal  oiling,  there  are  two  general 
systems  in  use :  the  pressure  form,  and  the  splash  type.  A  third,  which 
is  now  coming  rapidly  into  use,  is  a  combination  of  the  two,  called  the 
splash-pressure  system.  For  1917,  the  relative  popularity  of  these 
three  is  as  follows:  pressure,  on  30  per  cent;  splash,  on  35;  splash- 
pressure,  on  35. 

In  the  pressure  form  (or  its  modification,  the  splash-pressure), 
the  pressure  may  be  produced  in  a  number  of  ways:  by  a  single  large 
pump;  by  a  series  of  small  pumps,  one  for  each  bearing  lead;  or  by  a 
reservoiTi  or  tank^  kept  filled  by  a  separate  pump  (gravity  ptessvise^ . 


GASOLINE  AUTOMOBILES 


Splash-Pressure  Feeding.  One  of  the  best  and  most  successful 
tj-pes  of  liil>ri(.'ittion  systems  is  that  in  which  the  oil  is  fed  under 
pressure  to  tlic  (Ufforcnt  bearings. 

In  tile  s|)lasli-pressurc  system,  the  oil  to  all  the  crankshaft  and 
coiinectiiig-roil  bcariiifis,  to  the  timing  gears,  and  to  the  upper  portion 
of  tlie  cylinder  walls  is  supplletl  through  the  medium  of  a  gear-oil 
piniip  driven  usually  by  worm  gearing  from  the  camshaft.  The  other 
bearings  within  tlii'  engine  are  lubricate*!  by  oil  spray  tlirown  from 
the  crankshaft.     Sut-li  a  system  is  shown  in  Fig.  213. 

Orerhinil.  Tlio  same  units  .are  necessary  in  all  splasli-pressure 
svstenis,  Init  they  can  he  and  arc  used  in  widely  different  ways.     It 


GASOLINE  AUTOMOBILES  307 

From  here  it  passes  back  through  the  pipe  D  to  the  inner  distributing 
pipe  E;  Has  serves  to  keep  the  troughs  FF,  filled.  At  the  middle  part 
of  the  downward  stroke,  the  scoop  on  the  bottom  of  each  connecting 
rod  dips  into  its  own  oil  reservoir  and  splashes  up  a  fine  spray  of  oil. 
At  high -speeds,  the  four  rods  fill  the  whole  interior  of  the  crankcase 
and  the  lower  parts  of  the  four  cylinders  with  a  mist  of  oil.  This  is  . 
sufficient  to  lubricate  everything  thoroughly.    In  a  system  of  this 


.  kind,  the  strainer  is  of  great  importance  and  must  be  kept  clean. 
Sinailarly,  the  oil  sump  should  be  drained  very  frequently,  at  least 
every  1  OCX)  miles. 

Studebaker.  The  Studebaker  system  is  very  similar,  except  that 
the  oil  pump  is  outside  of  the  crankcase  and  set  higher  up.  It  is  of 
the  simple  gear  t^pe  and  is  not  liable  to  derangement.  The  system 
is  equipped  with  an  oil-level  indicator  on  the  side  of  the  case,  which 
shows  the  quaotity  within  the  case. 


308 


GASOLINE  AUTOMOBUGS 


Single-Pump  Pressure  Feeding.  The  drilled  crankshaft,  as 
shown  in  Fig.  21.'5,  is  a  necessity  in  all  pressure  systems,  as  it  also  n 
in  all  combination  splaah-pressiire  systems.  This  can  be  seen,  and 
perhaps  the  whole  system  explained  more  clearly,  bj'  referring  to 
Fig.  215,  In  this  the  single  pump  working  direct  is  used,  tlius  differ 
ing  from  the  reservoir  s\'stem  explained  above.  This  diagram  shows 
also  how  the  oil  is  forced  to  flow  through  the  three  bearing  leads  to 


GASOLINE  AUTOMOBILES  309 

Generally,  pockets  are  provided  inside  the  motor  to  catch  the 
mist  and  force  it  to  flow  to  the  camshaft  and  other  bearings  besides 
the  crankshaft,  but  in  this  case  it  will  be  noted  that  the  camshaft 
bearings  have  individual  supplies  through  the  medium  of  a  camshaft 
oiling  pipe. 


An  objection  to  lubricating  systems  of  this  type  is  that  in  case 
there  are  several  leads  to  different  bearings  one  of  them  may  become 
obstructed  without  anything  to  indicate  this  condition  or  to  over- 
come it  until  the  bearing  involved  becomes  overheated  and  ruined. 
If  one  lead  becomes  obstructed,  the  oU  can  still  continue  to  feed-Odt 


810  GASOLINE  ACTOIIOBILEB 

through  the  others,  thus  relimng  die  piuaauit  m  i 
Donnsl  maoDer  and  failing  to  levol  a  anious  d 

Sieanu.  The  Steams-Kni^it  tyttem  is  ahown  in  fff.  218. 
The  oil  19  circulated  by  s  pump  (not  visible  in  this  iketcli)  at  the 
^nt  end  of  the  eccentric  shaft  2).  After  paamig  thrau^  a  suua 
and  the  pump,  it  is  forced  tbnx^  a  etrainer  A  in  the  filter  E,  thenee 
through  pipes  to  the  pump-ehaft  bearing  eccentric-Aaft  chains 
and  main  crankshaft  bearings.  It  readies  the  csankshaft  bearings 
throu^  the  oil  inlet  F,  the  drilled  boles  in  the  oankdiaft  bong  indi- 
cated at  G.  From  these  holes,  it  icadus  the  bidloir  cater  ol  die 
connecting  rods  K,  andthustothefMstonpinsandp 
At  the  bottom  of  each  connecting  rod,  there  are  time  mat 
holes  through  which  sufficient  oil  escapes  to  lubricale  the  i: 
outer  sleeveswhich  take  the  place  of  the  valves.  A  gage  ou  tbc  da^ 
board,  or  cowlboard.  indJcatca  the  oil  pressure  and  should  read  t. 
1  to  5  pounds  with  the  throttle  closed  and  the  motor  idling, 
from  40  to  60. pounds  when  the  throttle  is  wide  open  and  the  t 
running  normally  or  at  high  speed. 

Regulator  Connectwl  to  Throttle.    Tlie  variation  on  this  pre 
sure  is  controlled  entirely  by  the  liy-pass  in  the  main  oil  lead,  which 


GASOLINE  AUTOMOBILES 


311 


On  high-speed  ami  multi-cylinder  motors  (which  are  almost 
invariably  high-speed  forms),  the  lulirication  assumes  an  importaace 
not  hitherto  attatrhed  to  it.     This  is  ros[M)ii:jibIc  for  the  pressures  used 


ami  for  the  wide  spread  use  of  mecliaiiically  driven  jiositive  pumps. 
Formerly,  pressures  of  from  a  few  ounces  to  4  or  5  pounds  were  con- 
sidered sufficient.  Now,  pressures  as  higli  as  00  and  70  pounds  are 
not  unusual.     These  trcnien<lous  pressures,  hi>wever,  have  necessi- 


312  GASOLINE  AUTOMOBILES 

tated  a  sj'stem  much  more  carefully  constructed,  assembled,  and  used 
than  was  the  case  previously. 

Mannon.  The  Marmon  system  is  not  radically  different  from 
that  just  described,  but  there  are  a  nimiber  of  small  Individual  points 
worthy  of  mention.  The  filling  is  not  through  the  usual  crankcase 
breather  pipe,  but  through  an  opening  in  the  top  of  the  cylinder  head 
t,  Fig.  217.  From  this  opening  the  oil  flows  around  the  valve  push 
rods  (the  motor  had  overhead  valves  as  will  be  noted)  down  into  tbe 
bottom  of  the  oil  pan  2.  After 
screening  at  3,  it  passes 
through  the  throttle-controlled 
regulator  to  the  oil  pump  4  on 
the  rear  end  of  the  camshaft. 
The  main  feed  pipe  is  marked 
5,  the  pressure  gage  6.  lead  to 
crankshaft  bearings  7,  hollow 
in  crankshaft  S,  connecting-rod 
bearing  9,  cylinder  waits  10. 
ball  check  valve  /  /  to  govern 
pressure    in    main    feed    pipe 


GASOLINE  AUTOMOBILES 


313 


wTvpeoIC 

Simplicii 


a  cam,  and  in  a  few  cases  the  vane  pump.  While  essentially  the  same 
as  the  forms  used  for  pumping  water  described  previously,  they  are 
smaller  in  actual  size  and  have  some  few  different  details.  In  the  gear 
form,  which  is  shown  in 
Fig.  219,  one  gear  b  driven 
directly  from  the  engine  and, 
in  turn,  drives  the  other, 
their  rotation  foreing  the  oil 
along  in  the  direction  of 
rotation.  Usually  a  by-pass 
with  a  check  valve  is  pro- 
vided, and  when  the  pipe 
is  obstructed  or  the  pres- 
sure rises  for  any  other  rea- 
son, this  opens  and  the  oil  passes  around  the  pump  at  low  pressure, 
equalizing  the  system. 

The  cam-operated  plunger  form  is  shown  in  Fig.  220.  This  is 
the  method  of  drive  adopted  for  mechanical  lubricators,  but  few 
engines  have  an  individually  con- 
structed pump  of  this  type.  It  is 
simple,  easy  to  regulate,  seldom  gets 
out  of  order  and  can  be  arranged  to 
give  a  different  supply  at  each  plunger 
should  the  system  warrant  or  necessi- 
tate this.  A  good  example  of  the 
plunger  form  is  the  oil  pump  on  the 
Reo  engine,  shown  in  Fig.  221.  This 
works  as  follows:  When  the  pump 
plunger  A  is  moved  upward  by  the 
curved  eccentric  B,  it  draws  oil  through  the  ports  C  and  the  screen 
D,  as  the  entire  lower  part  is  submerged  in  the  oil.  When  the  max- 
imum amount  of  oil  is  drawn  into  the  pump  chamber  in  this  way,  the 
plunger  descends,  the  ball  E  rises,  and  the  oil  flows  up  inside  the 
hollow  plunger  to  the  top  ports  F,  through  these  to  the  surrounding 
chamber  O,  and  thence  to  the  outlet  H  and  into  the  oil  pipes.  This 
fonn  is  very  accurate  and  reliable. 

Meihoda  qf  Driving  Pumps.    Another  point  of  considerable 
imptvtaace  to  the  repair  man  is  the  method  of  driving  the  pump, 


d  Pluncer 


314 


GASOLINE  ACT0M0BILE8 


Oh 


since  this  influences  its  location  and  its  accessibility.  There  are  but 
two  general  methods  of  driving.  One  is  by  means  of  a  special  oil-pump 
shaft,  in  Ti'hich  the  pump  will 
quite  K<'nerally  be  found  in  the 
bottom  of  the  oil  sump  or  very 
close  to  it;  the  other  is  from 
some  part  of  a  shaft  used  for 
other  purposes,  in  which  case 
tile  position  may  vary  widely. 
Examples  of  thefirst.orspccinl- 
shaft  method,  will  be  seen  in 
Overland,  Fig.  214,  and  Cad- 
illac, Fig.  215.  Examples  of 
the  second  method  are  seen  in 
Stearns,  Fig.  216,  and  Mamion, 
Fig.  217,  in  both  of  which  the 
camshaft  is  used. 

In  Fig.  222,agear  b  placed 
directly  upon  the  rear  end  of 
the   camshaft   meshing,    with 


GASOLINE  AUTOMOBILES 


GASOUNE  AUTOMOBILES 


GASOLINE  AXJTOMOBILES 


31? 


on  the  camshaft.  It  projects  out  at  right  angles  on  the  side  between 
cylinders  2  and  3.  It  is  possible  to  arrange  a  system  of  this  kind  so 
that  an  extra  cam  is  not  needed,  one  of  the  regular  valve  cams  doing 
the  work  of  pmnping  the  oil.  This  makes  s  simple  and  inexpensive 
arrangement.  The  oil  suction  pipe  is  marked  B  and  the  pipe  carry- 
ing the  supply  to  the  bearings  is  marked  C.  Attention  is  called  to  the 
connecting-rod  oil  scoops  D,  the  feed  adjustment  E,  the  pressure- 
relief  valve  F,  and  to  the  main  oil  lead  G. 

Individual  Pump  Pressure  Feeding.  The  expedient  of  feeding 
the  oil  by  individual  pumps,  independently  driven  and  capable  of 
individual  adjustment  which  enables  them  to  feed  any  desired  amount 
of  oil  to  any  par- 
ticular bearing  re- 
gardless of  the 
amount  that  may 
be  fed  to  any  other 
bearing,  has  been 
widely  applied.  In 
such  a  system,  if  j 
obstruction  of  any  | 
one  of  the  leads  1 
should  occur,  it  is 
almost  certain  to  be 
forced  out  by  the 
action  of  the  pump, 
which,  in  all  lubri- 
cating systems  of  established  tj^ie,  is  made  capable  of  working  against 
enormous  pressure. 

One  of  these  lubricators,  made  for  eight  feeds,  is  shown  in  Fig. 
224.  By  extending  the  casing  and  the  longitudinal  shaft  inside  and 
adding  more  pumps,  thb  tv-pe  is  capable  of  extension  to  any  desired 
number.  The  eight-feed  form  shown  allows  of  one  lead  to  each  of  the 
three  main  bearings  of  a  four-cjlinder  engine,  one  each  to  the  four 
cylinder  walls,  with  a  lead  remaining  for  the  gear  case  at  the  front 
of  the  motor. 

Gravity  Feeding.  Feeding  of  oil  by  gravity  to  one  or  more  bear- 
ings 13  a  method  that  has  been  employed  with  some  auCcess,  but  it  is 
now  encountered  only  in  rare  instances  in  autMnobile  power  ^lantft. 


318 


GASOUNE  AUTOMOBILES 


^lash  Lubrication.  The  feeding  of  oil  to  bearing  surfaces  by 
the  simple  expedient  of  enclosing  a  quantity  of  it  in  a  resen-oir  in 
■  which  the  working  parts  are  also  contained  is  a  successful  and  widely 
used  scheme  in  automobile  motor  construction. 

In  the  splash  lubrication  system,  as  will  be  shown  in  detail  later, 
the  lower  ends  of  the  connecting  rods  "splash"  up  the  oil  which  is  in 
the  bottom  of  the  crankcase  in  the  form  of  a  huge  puddle.  Since  thb 
method,  formerly'  almost  universal,  has  been  criticised  as  wasteful  <rf 
oi!  as  well  as  i)ru<luctive  of  much  needless  smoke,  it  has  been  modified 


.  Ili;it  tilt-  scix.p 
iirroiv  trouylis  \i 
sti-m  is  tliJit  at 


FiK.  22.V    Ty,«.-.,]  S. 
Typr  (irraw  f.ip  *i 


by  the  majority  of  tnakci 

ncctinf;  rods  dip  into  snui 

Another  objt't-tion  to  thi: 

is  thrown  iirouuil  tlie  interior  of  tlii 

the  initini  rotation  of  the  r(«ls  has 

supply  into  a  mist,  whih'  at  low  s|H' 

for  the  work  the  engine  is  doing. 

The  latter  olijVction  has  tiei-u  o\ 
mnkiiig  tlie  trouglis  into  wliieli  the 
able  and  attin-hed  to  the  throttle  le 
o|x-ned  wide  to  develo])  niii\ininm  jxi 
higher,  allowing  tlie  .-icooiis  to  dip  d 
greater  amount  of  hibrieaiit. 

External  Lubrication.     In  the  hibrieatioii  of  the  external  parts 
of  the  motor,  such  as  the  pump  shaft,  magneto  shaft,  oiler  shaft,  faa 


in  the  ends  of  the  cor- 
1  for  this  purpose. 
It  at  high  .speecls  t«)o  little  oil    \ 
■yliiiders  and  crankcase,  since    I 
■hnnied  or  Iwaten  the  entire    \ 
s  too  much  is  thrown  arountl 

come  in  the  newer  engines  b^' 
niie(tiiig-ro<l  scoops  dip mov-' 
T.  s(.  that  when  the  latter  i=* 
!T,  tlie  tnmglis  are  brought  ufF 
rn  dtt'iKT  and  thus  supply  a 


GASOLINE  AUTOMOBILES  319 

shaft,  generator  shaft,  air  pump  shaft,  etc.,  an  entirely  different 
method  of  lubrication  is  necessary — one  that  is  more  simple  in  every 
respect,  allows  the  use  of  more  simple  lubricating  devices,  and  does 
not  require  anything  like  the  care  and  adjustment  previously  pointed 
out  for  the  internal  parts. 

Oil  and  Grease  Cups.  Chief  among  the  devices  used  for  lubricat- 
ing these  outside  parts  are  oil  and  grease  cups,  the  oil  cups  being  used 
in  decreasing  quantities  and  the  grease  cups  in  increasing  quantities. 
Formerly,  oil  cups  were  much  used,  but  they  gave  poor  satisfaction, 
collected  dirt,  and  were  unsatisfactory  generally.  In  the  use  of 
grease  cups,  there  are  but  three  things  to  observe:  They  should  be 
large  enough,  accessible,  and  easy  to  fill. 

For  application  to  spring  eye-bolts  there  is  a  particular  type 
of  grease  cup.  This  grease  cup  is  of  the  type  that  feeds  by  being 
occasionally  screwed  up  a  small  distance  as  the  bearing  uses  up  the 
lubricant,  and  its  positive  action  is  rendered  more  certain  by  the  use 
of  a  detent  (not  illustrated)  that  holds  the  cover  in  any  position  in 
which  it  may  be  left.  The  grease  is  contained  in  the  entire  cap  which, 
when  imscrewed  from  the  lower  portion,  is  readily  and  conveniently 
filled  by  scooping  up  the  grease. 

A  form  quite  generally  used  is  the  simple  cup  shown  in  Fig.  225. 
This  is  a  screw-compression  cup  from  which  the  lubricant  is  forced  out 
by  screwing  down  on  the  reservoir.  This  form  is  prevented  from  com- 
ing loose  by  the  compression  spring,  here  shown  very  much  compressed 
below  the  ratchet,  which  governs  the  screwing  down  of  the  reservoir. 
To  fill  the  reservoir,  the  ratchet  portion  is  held  down  and  the  top 
screwed  off,  turning  in  the  reverse  of  the  usual  direction.  Although 
the  top  is  fitted  with  a  wing  handle,  it  can  hardly  be  considered  easy 
to  refill. 

Another  widely  used  form  is  seen  in  section  in  Fig.  226.  This  has 
a  larger  handle  and,  in  this  respect,  may  be  considered  easier  to  fill. 
A  t>T)e  which  is  rapidly  coming  into  use  and  has  all  the  advantages  of 
the  other  two,  and  more,  is  shown  in  Fig.  227.  This  is  a  plain 
screw  type  with  a  large  handle,  but  the  cap  is  of  sheet  brass  and 
is  spnmg  into  place.  As  this  is  sprung  off  by  the  plunger  inside 
when  screwed  away  out,  filling  is  reduced  to  a  matter  of  sec- 
onds. The  plunger  screws  all  the  way  in  and  affords  pressure  all 
the  way. 


318 


GASOLINE  AUTOMOBlLEa 


Splash  Lubrtcalion.  The  feedinK  of  oil  to  iH^aruif;  surfares  hj- 
the  simpip  expedit-nt  of  enclosing  a  quantity  of  it  in  a  reservoir  in 
■  which  the  workitiR  parts  are  also  contained  is  a  successful  and  widely 
used  scheme  in  automobile  motor  construction. 

In  the  splash  lubrication  s>-stem,  as  will  be  shown  in  detail  later, 
the  lower  ends  of  the  connecting  rods  "splash"  up  the  oil  which  is  in 
the  bottom  of  the  crankcase  in  the  form  of  a  huge  puddle.  Since  this 
method,  formerly  almost  universal,  has  been  criticised  as  wasteful  of 
oil  as  well  as  productive  of  much  needless  smoke,  it  has  been  modified 


GASOLINE  AUTOMOBILES  319 

shaft,  generator  shaft,  air  pump  shaft,  etc.,  an  entirely  different 
method  of  lubrication  is  necessary — one  that  is  more  simple  in  every 
respect,  allows  the  use  of  more  simple  lubricating  devices,  and  does 
not  require  anything  like  the  care  and  adjustment  previously  pointed 
out  for  the  internal  parts. 

Oil  and  Grease  Cups.  Chief  among  the  devices  used  for  lubricat- 
ing these  outside  parts  are  oil  and  grease  cups,  the  oil  cups  being  used 
in  decreasing  quantities  and  the  grease  cups  in  increasing  quantities. 
Formerly,  oil  cups  were  much  used,  but  they  gave  poor  satisfaction, 
collected  dirt,  and  were  unsatisfactory  generally.  In  the  use  of 
grease  cups,  there  are  but  three  things  to  observe:  They  should  be 
large  enough,  accessible,  and  easy  to  fill. 

For  application  to  spring  eye-bolts  there  is  a  particular  type 
of  grease  cup.  This  grease  cup  is  of  the  type  that  feeds  by  being 
occasionally  screwed  up  a  small  distance  as  the  bearing  uses  up  the 
lubricant,  and  its  positive  action  is  rendered  more  certain  by  the  use 
of  a  detent  (not  illustrated)  that  holds  the  cover  in  any  position  in 
which  it  may  be  left.  The  grease  is  contained  in  the  entire  cap  which, 
when  imscrewed  from  the  lower  portion,  is  readily  and  conveniently 
filled  by  scooping  up  the  grease. 

A  form  quite  generally  used  is  the  simple  cup  shown  in  Fig.  225. 
This  is  a  screw-compression  cup  from  which  the  lubricant  is  forced  out 
by  screwing  down  on  the  reservoir.  This  form  is  prevented  from  com- 
ing loose  by  the  compression  spring,  here  shown  very  much  compressed 
below  the  ratchet,  which  governs  the  screwing  down  of  the  reservoir. 
To  fill  the  reservoir,  the  ratchet  portion  is  held  down  and  the  top 
screwed  off,  turning  in  the  reverse  of  the  usual  direction.  Although 
the  top  is  fitted  with  a  wing  handle,  it  can  hardly  be  considered  easy 
to  refill. 

Another  widely  used  form  is  seen  in  section  in  Fig.  226.  This  has 
a  larger  handle  and,  in  this  respect,  may  be  considered  easier  to  fill. 
A  type  which  is  rapidly  coming  into  use  and  has  all  the  advantages  of 
the  other  two,  and  more,  is  shown  in  Fig.  227.  This  is  a  plain 
screw  type  with  a  large  handle,  but  the  cap  is  of  sheet  brass  and 
is  sprimg  into  place.  As  this  is  sprung  off  by  the  plunger  inside 
when  screwed  away  out,  filling  is  reduced  to  a  matter  of  sec- 
onds. The  plunger  screws  all  the  way  in  and  affords  pressure  all 
the  way. 


322  GAli^OLINE  AUTOMOBILES 

Oils  and  Qreases 

Characteristics  of  Good  Oils.  The  variety  of  oila  aod  greases 
recuniineiitled  for  automobile  use  is  so  extensive,  and  there  are  sii 
many  cheap  and  worthless  lubricating  compounds  on  the  market, 
that  it  is  almost  impossible  for  the  purchaser  without  technical  knowl- 
edge to  discriminate  between  them.  The  various  tests  from  time  to 
lime  recommended,  whereby  the  user  may  ascertain  for  himself  the 
quality  of  the  lubricant  he  is  using,  are  rarely  of  positive  value,  sine* 
the  compounders  of  the  shoddy  oils  and  greases  are  usually  sufficiently 
expert  chemists  to  concoct  admixtures  that  will  successfully  pass 
such  simple  tests  as  are  a^'ailable  to  the  average  layman,  and  will  fail 
only  under  the  more  critical  analysis  of  a  competent  chemist,  or  under 
the  se\ere  and  more  risky  practical  demonstration  that  results  from 
long  use,  in  the  course  of  which  the  worthtessness  of  the  lubricant  is 
likely  tii  be  found  out  only  at  the  cost  of  serious  injury  to  the 
mechanism.  The  consequence  is  that  the  only  really  safe  policy  to 
fiilluw  is  the  |)urchase  of  the  highest  grades  of  oila  and  greases, 
marketed  by  concerns  of  established  reputation. 

Tiic  oils  generally  found  best  for  gasoline-engine  cylinder  lubri- 
cation aic  tlic  mineral  oils  derived  from  ]>etroleuni.  though  castor 


GASOLINE  AUTOMOBILES  323 

admixed  in  very  small  percentages  with  cylinder  oib,  gearbox  greases, 
etc.,  there  is  no  question  but  what  it  greatly  conduces  to  smooth 
running  and  to  long  life  of  bearings.  Its  resistance  to  the  very 
highest  temperatures  makes  it  constitute  a  considerable  safeguard 
against  immediate  injury  in  case  of  neglect  to  replenish  the  lubri- 
cants as  often  as  is  properly  required. 

Testing  Oils  for  Acid,  Etc.  Oils  must  be  purchased  with  much 
care.  Once  an  oil  is  found  which  does  the  work  satisfactorily,  it 
should  be  adhered  to  consistently.  No  two  oils  are  exactly  alike,  and 
for  that  reason,  no  two  will  do  the  same  work  under  the  same  condi- 
tions in  the  same  way.  So,  it  is  advisable  to  experiment  only  until 
an  oil  is  found  which  will  do  the  work.  Thereafter,  stick  to  that 
brand.  As  an  instance  of  the  impurities  which  may  be  found  in  oils, 
acids  may  be  mentioned.  These  are  fatal  to  delicate  and  closely 
machined  parts,  such  as  ball  bearings,  cylinder  walls,  pistons,  etc.,  and 
consequently  they  should  be  watched  for. 

Pure  mineral  oils  contain  little  acid,  and  what  they  do  contain 
is  readily  determined.  Vegetable  and  animal  oils,  on  the  other  hand, 
all  have  acid  content  and  under  the  action  of  heat  this  mav  be  lib- 
erated.  A  simple  home  test  may  be  practiced  as  follows :  Secure  from 
a  druggist  a  solution  of  sodium  carbonate  in  an  equal  weight  of  water. 
Place  this  in  a  small  glass  bottle  or  vial.  To  test  an  oil,  take  a  small 
quantity  of  the  lubricant  and  an  equal  amount  of  the  sodium  solu- 
tion. Put  both  in  another  bottle,  agitate  thoroughly,  and  then  allow 
it  to  stand.  If  any  acid  is  present,  a  precipitate  will  settle  to  the 
bottom,  the  amount  of  the  precipitation  being  a  measure  of  the 
amount  of  acid  present. 

Another  method  is  to  allow  the  acid,  if  there  is  any,  to  attack 
some  metal.  To  do  this  proceed  as  follows:  Soak  a  piece  of  cloth  or, 
preferably,  wicking  in  the  oil  suspected  of  containing  acid.  Select  a 
piece  of  steel  at  random  and  polish  it  to  a  bright  surface.  Wrap  the 
steel  in  the  soaked  rag  or  wicking,  and  place  in  the  sunlight  but 
protect  it  from  wind  or  weather.  Allow  it  to  stand  several  days,  and  if 
there  is  no  sign  of  etching  of  the  surface,  repeat  with  a  freshly  soaked 
rag,  being  careful  to  use  the  same  oil  as  before.  After  two  trials, 
if  no  sign  of  the  etching  appears,  you  may  consider  it  free  from  acid. 

Principles  of  Effective  Lubrication.  To  render  lubrication 
positive  and  effective  there  are  certain  conditions  regardviv^  \k^ 


324  GASOLINE  AUTOMOBILES 

design  of  bearings  anH  the  fee'Iing  of  lubrimtits  that  must  be  scru- 
pulously observed. 

The  proper  applieiitiim  of  a  lubrieant  to  a  revolving  sli.ift 
passing  through  a  bearing  requires  that  definite  space  be  provided 
between  shaft  and  bearing  for  the  lubricating  material.  The  amount 
of  this  space  varies  with  the  size  of  the  shaft,  the  speed  of  rotation, 
and  other  conditions,  but  in  a  general  way  it  can  be  specified  that 
tlie  space  must  be  greater  as  the  shaft  diameter  incTcases,  and  greater 
for  Iieavy  oils  and  low  speeds  than  for  light  oils  and  high  speeds. 
For  the  crankshafts  of  automobile  engines,  to  take  a  specific  example, 
it  is  rarely  desirable  to  have  the  bearing  smaller  than  from  .0(10.5 
to  .0015  inch  larger  than  the  shaft.  The  annular  space  thus  pro- 
vided, as  suggested  at  A  m  the  end  and  sectional  views  in  Fig.  229,  is 
occupied  by  tlie  lubricant,  which,  coutrarj'  to  another  general  impres- 
sion, will  not  be  squeezed  out  unless  the  shaft  is  loaded  above  its 


GASOLINE  AUTOMOBILES 


times  erroneously  supposed,  but  to  provide  an  oit  film  of  the  necessary 
uniform,  instead  of  an  irregular,  thickness. 

LUBRICATION  TROUBLES  AND  REMEDIES 
Care  of  Lubricant  in  Cold  Weather.  Nearly  everyone  realizes 
the  amount  of- care  necessary  with  cooling  water  in  freezing  weather, 
but  few  realize  that  extreme  cold  has  practically  the  same  effect  upon 
lubricants.  In  the  coldest  weather,  a  lighter  grade  of  oil  specially 
made  to  withstand  low  tempera- 
tures should  be  used.  If  a 
special  oil  cannot  be  obtained, 
the  lighter  thinner  quality  will 
suffice,  as  even  when  thickened 
up  by  the  low  temperatures  this 
oil  will  flow  more  readily  than 
the  thick  oils.  Sometimes  the 
slow  circulation  of  the  oil  in  cold 
weather  allows  the  motor  bear- 
ings to  run  dry  and  heat.  This 
trouble  can  be  remedied  by 
changing  to  a  lighter  oil.  The 
same  is  true  of  the  clutch  oil 
which  is  in  the  multiple  disc  n 
running  in  oil.  Thick  oil  in  this 
in  cttld  weather  will  often  thicken 

up   and   stick  so  the  clutch   will      Flg-WO.     Munnmth  Gnur  Cud  ror  Cunce  Vh 
,  ,,  CoartavB/  ■Molar  JTbtU" 

not  work  well. 

Mammoth  Qrease  Qun.  For  the  average  shop  which  handles  a 
good  many  cars  a  day,  too  much  time  is  wasted  in  using  an  ordinary 
method  of  filling  a  transmission,  rear  axle,  or  other  lai^  part,  with 
grease.  A  mammoth  grease  gun  can  be  constructed  to  do  this  same 
work  in  a  few  seconds.  A  form  operated  by  compressed  air  is  shown 
in  Fig.  230.  It  consists  of  a  steel  cylinder  about  8  inches  in  diameter 
and  perhaps  7  feet  long  mounted  vertically  on  a  platform  which  is  set 
on  castors  so  that  it  can  be  wheeled  around  the  shop  as  needed.  A  free 
piston  is  placed  in  the  cjlindcr,  abo^e  the  grease,  and  air  admitted 
through  the  central  opening  in  the  screw  top  by  screwing  on  a  com- 
pressed air  hose.     The  outlet  hose  at  the  bottom  is  made  lou% 


CASOLINE  AUTOMOBILES 


enough  to  rearh  any  ordinarj'  point  on  the  average  car.  When  a 
transmission  is  to  be  filled,  the  platform  is  wheeled  up  to  the  car, 
the  bottom  hose  put  in  tlie  transmission,  and  the  cock  opened.  Then 
the  air  hose  is  coniiectt.'d  and  the  pressure  turned  on;  the  grease  will  be 
forced  out  in  a  hurry,  filling  the  case  in  a  few  minutes  regardless  of 
the  quantity  nee<U'd.  A  somewhat  similar  device  can  he  made  in  a 
smaller  size.  This  de\icc  is  almost  an  exact  copy  of  the  ordinary  hand 
j^rease  gun,  but  it  has  a  rod,  threaded 
through  the  cap,  which  operates  the 
plunger.  Oneman  can  hold  the  gun  while 
another  turns  the  handle,  which  forces 
out  a  tremendous  quantitj'  of  grease  in  a 
short  time. 

Oil  Tank  and  Outfit  for  Testii^ 
Bearings.  A  tank  for  testing  the  leakage 
of  bearings,  particularly  engine  b 
that  are  loose,  may  be  constructed  by 
fixing  in  the  top  of  a  small  tank  a  gage 
which  will  read  up  as  high  as  20  pounds, 
an    inner-tube    valve    stem    for    sup- 


AruuiT  Oi^ 


GASOLINE  AUTOMOBILES 


327 


grouped  ova  a  small  pan  which  catches  the  drip.  Filling  these 
barrels  is  easier  than  it  seems.  Simply  coimect  a  pipe  from  the 
barrel  of  new  oil  to  the 
overhead  barrel  to  be 
filled,  apply  the  air  pres- 
sure carefully  at  the 
bung,  and  the  oil  will 
be  forced  up. 

A  more  simple 
method  of  covering  and 
protecting  the  barrels  is 
to  have  a  box,  or  stand, 
large  enough  for  three  or 
more  barrels,  made  from 
light  lumber.  Then  bore 
a  small  hole,  at  the  place 
where  each  barrel  will  n,.  232.  Method  of  ei. 
stand,  for  the  faucet,  as  couhov  «/ ■  M,aor  woru- 

Fig.  233  shows.  Generally,  three  barrels  will  be  sufficient,  as  one 
for  heavy  oU,  one  for  light  oil,  and  one  for  kerosene  will  cover  all 
ordinary  work.  The  shelf 
which  holds  the  various 
measures  should  be  at- 
tached to  the  frame. 

A  convenient  oil- 
drain  rack  in  the  form  of 
a  small  square  box,  say 
6  to  8  inches  deep,  can  be 
made  with  tin.  Punch  a 
series  of  small  and  me- 
dium size  holes  in  the  top 
of  the  box.  When  the 
funnel  has  been  used  for 
filling  an  oil  tank  or  meas- 
ure, it  can  be  placed  in  the 
rack  and  allowed  to  drain.  In  this  way,  oil  waste  is  minimized  and 
the  place  is  kept  free  from  oil  drippings,  which  soon  gather  dust  and 
then  are  tracked  into  office  and  customers'  cars. 


Fi(.  233.     Eamly  Coutnictcd  Bo: _. 

Protdctinc  Oil  BattbU 
Cinritti  Bf  "  Moler  Wvid" 


GASOLINE  AUTOMOBILES 


Oil  Settling  Tanks, 

as  imtli  mauufiictuRTs  ii 


If  lubricating  sj-stems  are  drained  as  often 
Till  oil  people  recommend,  there  is  a  good  deal 
of  oil  around,  which  is  heavy  and  of  a  doubt- 
fnl  quality.     But  if  this  oil  can  be  allowed 
to  stand,  op  can  be  filtered,  a  large  quantity 
of  it  can  be  used  for  other  purposes.     If  a 
tank  of  fairly  large  size  is  made  with  a  series 
of  faucets  or  cocks  at  different  levels,  some- 
what like  that  shown  in  Fig.  234,  enough  of 
the  oil  can  be  saved  to  resell  at  a  good  profit, 
or,  if  there  is  no  idea  of  selling  it,  it  can  be 
used  for  other  machinery'  or  for  other  pur- 
poses, where  the  need  for  high-quality  oil  is 
not  so  great.     The  oil  drawn  off  the  crank- 
case  is  poured  in  at  the  top  and  gradually 
*''*cS»Brv'ii'rio''u-.'L."v(i"''"     settles,  the  heavier  sediment  going  to  the 
bottom,  the  thickest  oils  next,  and  so  on, 
until  the  top  will  sliow  a  fair  quality  of  light  oil,  and  the  layer  next 
to  it  a  fair  quality  of  medium  oil,  and  so  on  down  to  the  bottom. 
Oil    Filtering    Outfit. 


GASOLINE  AUTOMOBILES 


329 


two  or  three  bunches  of  waste  will  lose  practically  all  its  impurities, 
coming  out  perfectly  clear.  After  each  use,  the  waste  is  removed 
and  burned,  and  new  waste  put  in  its  place. 

Oil  measures,  funnels,  and  other  containers  should  always  be  kept 
clean.  The  oil  left  on  them  soon  collects  dust  and  dirt,  and  the  next 
time  some  of  this  old  oil  will  be  poured  into  the  engine  with  the  fresh 
oil.  Ail  oils  do  not  mix,  and  chemical  action  may  be  set  up 
between  old  oil  of  one  quaUty  on  the  can  and  new  oil  of  another 
quality  in  the  can.  Kerosene  or  a  little  gasoline  should  be  poured 
in  the  containers  or  funnels  to  clean  them  off.  This  liquid 
should  be  rinsed  out  of  the  cans  and  put  into  a  settling  or  filtering 
tank  and  practically  all  of 
it  recovered.  ['\  ji^jub. 

Bending  Oil  Pipes. 
Frequentjy  an  oil  pipe 
which  has  a  curve  or  spiral 
in  it,  or  even  a  series  of 
coils  has  to  be  replaced. 
If  bent  by  hand,  a  kink 
may  be  made  in  the  pipe 
which  will  lead  to  a  future 
break.  A  simple  fitting 
for  bending  these  pipes  can  be  made  in  a  few  minutes.  Take  a  piece 
of  hard  wood  about  .3  inches  square  and  9  inches  long  and  turn  it 
up  round  in  the  lathe,  then  down  one  end,  as  shown  in  Fig.  236,  and 
cut  the  spiral  grooves  or  threads  in  it.  These  shouki  be  about  ^ 
inch  in  width  and  cut  with  a  round-nosed  tool  so  as  to  get  a  smooth 
bottom  to  the  grooves.  When  a  pipe  is  to  be  bent,  fill  it  with  resin, 
a  fine  lead  rod,  or  anything  flexible.  The  wood  can  be  held  in  the  side 
of  the  vise  and  the  tubing  wound  onto  the  threaded  end.  If  the 
pipe  is  of  a  heavy  gage,  anneal  it  by  heating  and  plunge  it  into  cold 
water  before  starting  to  bend  it. 

Summary  of  Troubles  with  Lubrication  Systems 

Crankcase  Oil.  This  should  be  changed  about  every  500  miles  as, 
by  this  time,  the  lubricating  qualities  of  the  oil  are  nearly  exhausted. 
After  draining  the  oil,  wash  out  the  crankcase  with  kerosene  and 
see  that  the  kerosene  is  removed  before  putting  in  fresh  oil. 


Fw    230.     Hud  Wood  Fiiture  fat  Bendinc  Oil  Pipe 


330 


(  ;AS(  tLINE   AUTl )M( JBILKt^ 


Grease  Cups.  These  are  usually  Incateti  on  the  rear  axle,  steer- 
ing knuckles,  stt'erinfr-tiilumn  base,  and  many  other  parts.  They 
should  be  kept  foiistantly  filled  with  cnp  grease.  These  grease  cups 
should  not  be  confused  with  small  oil  holes  having  caps  which  can  be 
raised  but  not  unscrewed.  Grease  cups  should  be  screwed  down 
occasionally  in  order  to  force  the  grease  down  to  the  bearing  surface. 

Neglect  of  Lubricalion.  Neglect  of  lubrication  is  responsible 
for  many  troubles.  An\'  automobile  requires  careful  attention  to  its 
lubricating  system.  The  owner  will  find  it  to  his  advantage  financially 
to  see  that  all  necessary  parts  are  properly  lubricated. 

Steering  Gear.  The  steering-gear  parts  require  occasional  lubri- 
cation. TJiese  parts  include  steering  rod;  worm,  or  sector,  and  gear; 
steering  link  at  both  ends;  foot-pedal  pivot  or  bearing;  and  all  joints. 

Too  Much  Oil  in  Crankcase.  Usually  drain  cocks  are  provided 
in  the  crankcase  and  are  so  located  that  when  they  are  opened 
they  will  drain  off  only  the  surplus  oil. 

Troubles  with  Mechanical  Lubricator.  If  one  of  the  sight  feeds 
fills  with  oil,  it  indicates  too  rapid  feeding  of  oil.  Shut  ofT  the  valve 
on  the  tup  of  the  lubricator  till  the  glass  is  clear.  !f  it  does  not 
clear  up  shortly,  the  probability  is  that  it  is  nece.ssary  to  clean  the 


GASOLINE  AUTOMOBILES  331 

ball  bearings.  The  other  shafts,  as  pump,  oiler,  magneto,  air-pump, 
generator,  etc.,  are  generally  of  the  plain,  solid,  round  t^^je. 

Engine  bearings,  however,  are  generally  of  the  split,  or  halved, 
type,  the  upper  and  lower  halves  being  practically  duplicates.  A 
reason  for  this  construction  appears  as  soon  as  one  considers  the 
application  of  the  bearings  to  the  shaft.  It  is  granted  that  a  crank- 
shaft must  be  as  firm  and  solid  as  possible,  and  hence  it  must  be  made 
in  one  piece.  As  ball  bearings  also  are  made  in  one  piece,  there  arises 
at  once  the  difficulty  of  getting  the  bearings  into  place  on  the  one- 
piece  shaft.  This  difficulty  has  necessitated  cutting  the  shaft  or  else 
making  it  especially  large  and  heavy  in  those  cases  where  balls  are 
used.  With  the  split  type  of  bearing  there  are  no  troubles  of  this  kind 
and  the  bearings  are  adjustable  for  the  inevitable  wear. 

Plain  Bearings.  The  conditions  that  determine  the  proper 
proportioning  and  fitting  of  plain  bearings  have  already  been  referred 
to  in  a  preceding  paragraph. 

The  materials  of  plain  bearings  are  commonly  varied  to  meet 
different  conditions.  With  liberal  bearing  areas,  in  situations  where 
it  is  desired  to  bring  about  a  perfect  fit  with  the  minimum  amount 
of  labor,  and  to  protect  the  shaft  from  wear  in  case  there  is  failure  of 
the  lubrication,  the  various  types  of  babbitt  metal — which  usually 
are  alloys  of  tin  and  lead,  with  sometimes  some  admixture  of  antimony 
and  other  alloys — are  widely  regarded  as  the  most  serviceable.  Prob- 
ably the  greatest  advantage  of  a  babbitted  bearing  is  that,  if  the 
lubrication  should  fail,  the  low  melting  point  and  the  soft  material  of 
the  bearing  will  insure  its  fusing  out  without  injury  to  the  more 
expensive  and  valuable  shaft. 

Brass  and  bronze  bearings,  particularly  the  phosphor  bronzes 
and  the  bronzes  in  which  the  proportion  of  tin  is  high  and  that  of 
copper  low,  with  sometimes  the  admixture  of  a  proportion  of  zinc 
or  nickel,  will  allow  the  use  of  materially  higher  pressures  per  square 
inch  than  can  be  safely  permitted  on  babbitted  bearings. 

Steel  shafts 'in  cast-iron  bushings,  and  even  in  hardened-steel 
bushings,  make  much  better  bearings  than  one  might  think,  and 
though  immediate  trouble  is  to  be  anticipated  with  such  a  bearing 
should  its  lubrication  fail,  even  momentarily,  this  trouble  is  more  or 
less  true  of  any  bearing  that  can  be  devised.  Since  steel-to-steel  and 
steel-to-cast-iron  permit  much  the  highest  loadings  per  unit  of  are;i 


332  GASOLINE  AUTOMOBlLEy 

that  are  permisaible  with  any  type  of  metal-tometal  bearing,  the 
merits  of  tliese  materials  are  perhaps  less  appreciated  than  might  be  i 
desirable.     Steel  pins  through  ateel  bushings,  however,  we  noc  an 
uncommon  construction  for  the  piston-pin  bearings  in  hi^i-gnuk 
engines. 

One  noticeable  feature  of  plain  brouEe  or  other  plain  \ 
for  automobile  use  is  that  they  are  always  grooved  for  oil  c 
This  is  done  by  easing  off  the  edges,  then  cutting  a  spiral  gioowtgr 
hand  diagonally  across  to  the  other  edge  or  to  the  center  point  iriMnS 
similar  groove  from  the  other  side  is  met.  In  a  solid  bearing,  ijbs 
groove  is  generally  cut  both  ways  horn  a  centrally  drilled  (ul  hafi, 
while  in  split  bearings  the  grooves  in  each  half  usually  form  a  modilad 
letter  j-  when  viewed  in  plan,  that  is,  two  grooves  start  spirally  inward 
from  each  edge  near  the  ends,  and  all  four  meet  in'tfae  center.  "Daa 
central  point  may  be  the  spot  where  the  oil  enters  or  where  it  leaves; 
These  grooves  are  seldom  of  very  great  depth,  periiaps  .OOS  to  .010 
(eight  to  ten  thousandths). 

\ew  OUkss  Bearings.    A  form  of  bearing  that  is  new  to  the 
uutumubilc  but  old  in  years  is  now  coming  into  use.    This  is  made  of 


GASOLINE  AUTOMOBILES 


und  accurately  to  size.    This  type  of  roller  tain  be  depended 
■  work  without  breakage  or  injury  even  though  there  be  con- 


c  deflection  or  iiuiccuracy  in  the  alignment  of  shaft  or  casings, 
ibility  of  tlie  individual  rollers  taking  care  of  such  small  errors. 


vill  be  noted  in  Tig.  2:i!S  that  tlicrc  is  a  solid  .steel  shell  to  go  on 
t  and  fit  it  tightly,  aixl  an<)th('r  to  (it  into  the  case  or  support, 
jr  it  may  be,  perha|>s  attachwl  there  iiernianeiitly.     Between 


,334  GASOLINE   AUTOMOBILES 

tbi'5e  two  comes  the  cage  cairrjing  the  flexible  rollers.  Any  load 
imposed  upon  the  shaft  is  transmittet!  to  the  inner  sleeve  and  bv 
it  to  the  flexible  rollers ;  these  rollers  absorb  the  load  so  that  none  of  it 
reaches  the  outer  case.  Furthermore,  shocks  coming  to  the  case 
from  without  are  absorbed  by  the  flexibilitj'  of  the  rollers  and,  riw 
tersa,  shocks  to  the  shaft  do  not  reach  the  case. 

Ball  Bearings.  Probably  the  best  of  all  bearings,  except  for 
c-ertain  special  applications  in  which  it  is  difficult  to  utilize  them  in 
sufficiently  large  sizes  to  assure  durability,  are  the  annular  ball 
bearings  of  the  freneral  type  illustrated  in  Figs,  239  to  243,  inclusive. 
The  basir  fciiliirf  nf  the  most  successful  of  modem  annular  ball 
bearings  is  their  non-adjustability,  the 
balls  being  ground  very  accurately  to 
size  and  closely  fitted  between  the 
inner  and  outer  races  so  as  to  allow 
practically  no  play. 

The  reason  that  the  best  ball  bear- 
ings are  not  made  adjustable  is  that  in 
any  conceivable  Xy^  of  ball  bearing 
one  or  the  other  of  the  races  rotates 
.nd  the  other  remains  in  a  fixed 


GASOLINE  AUTOMOBILES 


335 


The  carrying  capacities  of  ball  bearings,  as  compared  with  those 
of  roller  bearings,  are  much  greater  than  a  casual  consideration  might 
lead  one  to  suppose.  Theoretically,  the  contact  of  a  roller  bearing — 
between  a  roller  and  one  of  the  races — is  a  line  contact,  while  that 
between  a  ball  and  a  ball  race  is  a  point.  But,  practically,  since  some 
deformation  occurs  in  even  the  hardest  materials  under  sufficient 
load,  the  line  contact  in  the  roller  bearing  becomes  a  rectangle  and  the 
point  contact  in  the  ball  bearing  becomes  a  circle.  Now  the  vital 
fact  is  that  the  area  of  the  rectangle  in  the  one  case  is  substantially 
equal  to  that  of  the  circle  in  the  other — ^with  given  quality  of  materials 
and  a  given  loading.  So  a  ball  bearing  is  fully  as  capable  of  carrying 
high  loads  as  a  roller  bearing;  besides,  it  avoids  the  risk  of  breakage 


JI 


Fig.  241.     Ball  Cage  of  Annular  Ball  Bearing 


that  usually  exists  with  rollers  because  of  the  impossibility  of  making 
them  perfectly  true  and  cylindrical. 

To  assemble  ball  bearings  of  the  type  illustrated  in  Fig.  240,  either 
of  two  expedients  may  be  adopted.  One  is  to  notch  one  or  both  of 
the  ball  races,  so  that  by  slightly  springing  them  a  full  circle  of  balls 
can  be  introduced  through  the  notch.  The  other  scheme  is  to  employ 
only  enough  balls  to  fill  half  of  the  space  between  the  races,  which 
permits  them  to  be  introduced  without  any  forcing,  after  which  they 
are  simply  spaced  out  at  equal  intervals  and  thus  held  by  some  sort 
of  cage,  or  retainer, -such  as  is  illustrated  in  Fig.  241. 

Ball  bearings  of  the  common  annular  type  are  quite  serviceable 
to  sustain  end  thrust  as  well  as  radial  loads.  For  the  best  results 
under  such  loads,  however,  it  is  essential  that  the  load  be  distributed 
equally  around  the  entire  circle  of  balls,  for  which  reason  the  system 


GASOLINE  AUTOMOBILES 


illustrated  in  Fig.  242  is  a  means  of  avoiding  the  unequal  distribution 
of  pressure  likelj'  to  result  from  the  slightest  inaccuracy  of  fitting.     In 


O' 


Tliruat  Loula 

this  construction  the  outer  ball  race,  shown  at  A,  is  provided  with 
a  spherical  outer  surface,  permitting  it  to  rock  slightly  in  the  mount- 
ing r,  into  the  position  shown  in  an  exaggerated  degree  at  B.  It 
thus  floats  automaticiilly  to  a  position  at  exact  right  angles  to  the 
ihaft  upon  which  it  is  mouiitedt 
and  so  insures  even  loading  of 


GASOLINE  AUTOMOBILES  337 

Combined  Radial  and  Ttirust  Bearing.  The  need  for  a  bearing 
which  would  take  ordinary  radial  loa<^s  well  and  also  sustain  thrust 
has  led  to  the  development  of  combined  radial  and  thrust  bearings, 
one  being  illustrated  in  Fig.  244.  This  is  constructed  to  take  either 
form  of  load  equally  well,  and  for  this  reason  has  displaced  a  pair  of 
ball  bearings  in  many  circumstances  where  formerly  it  was  thought 
necessary  to  use  a  radial  ball  bearing  to  sustain  the  load  and  a  thrust 
ball  bearing  to  absorb  the  end  thrust.  In  this  way  it  represents  an 
important  economy.  Furthermore,  it  is  economical  of  space,  as  it 
takes  less  room  than  the  former  pair  of  bearings  used  for  the  same 
two  purposes. 

FLYWHEEL  SUB-GROUP 

Importance  of  Flywheel.  With  the  growing  tendency  toward 
smoother  and  more  even  running  and  the  demand  for  lower  low 
speeds  and  higher  high  speeds,  the  flywheel,  which  was  looked  upon 
as  a  necessary  evil  for  many  years,  is  now  receiving  more  attention. 
The  designers  realize  that  the  flywheel  plays  an  important  part  in 
balancing — that  if  it  is  too  heavy  the  engine  will  be  slow  to  pick  up 
speed  and  will  not  run  very  fast,  and  that  if  it  is  too  light,  the  engine 
will  be  very  "touchy"  and  will  not  withstand  quick  variations  from 
high  to  low  or  low  to  high  speed,  nor  will  it  throttle  down  very  slowly. 

Flywheel  Characteristics.  WeigJits,  With  weights  being  reduced 
to  the  limit  in  order  to  get  higher  engine  speeds,  the  flywheel  has 
received  some  paring  down.  Formerly,  designers  erred  if  at  all 
on  the  heavy  side  with  flywheels,  but  when  they  began  changing  the 
entire  design  of  the  engine  to  save  a  few  pounds,  they  did  not  overlook 
the  flywheel.  In  the  flywheel,  too,  the  growing  use  of  counterweights 
has  had  an  influence.  / 

Sizes.  Designers  realize,  now  that  the  hampering  sub-frames  are 
out  of  the  way,  that  the  larger  the  diameter  the  better  the  flywheel 
effect  for  equal  or  less  weight.  As  a  result,  many  flywheels  have  been 
increased  in  diameter  as  they  have  been  reduced  in  weight. 

Shapes.  Flywheel  shapes,  that  is,  sections,  used  to  be  rec- 
tangular or  almost  square,  with  a  solid  web  or  spokes  practically  in 
the  center.  Clutches,  starter-ring  gears  on  the  outer  surface,  and 
other  contributing  causes  have  changed  the  character  of  flywheels 
so  that  few  have  the  rectangular  shape  or  character  now.  The  method 


338 


GASOLINE  AUTOMOBILES 


i)f  using  fan  blades  as  flj-wheel  spokes  has  also  fallen  into  disuse; 
although  at  one  time  it  was  widely  tried  and  appeared  to  be  a  means 
of  eliminating  the  fan  entirely. 

Something  of  the  present  shape  of  fij'wheels  can  be  seen  by  refer- 
ring back  to  Figs.  217,  222,  and  22.S.  In  the  first  figure,  the  flj-wheel 
has  a  triangular  section  with  a  solid  web  set  at  an  angle  so  as  to  bring 
the  flywheel  nearer  the  engine;  the  inner  surface  is  tajXTed  to  suit 
the  clutch ,  In  Fig.  222,  the  shape  is  entirely  different  and  apparently 
much  lighter.     Tlii.s  is  an  eight-cylinder  engine.     Here  the  flywheel 


GASOLINE  AUTOMOBILES  339 

Methods  of  Fastening  Flywheels.  That  part  of  the  fl>^heel 
which  is  most  interesting  to  the  repair  man  is  the  method  of  fastening, 
or  rather  the  inverse  of  this,  the  method  of  removal.  There  are  three 
general  methods  of  fastening  flywheels  to  crankshafts,  and  these  are 
shown  in  Fig.  245.  They  are  the  plain  round  end  with  a  key,  as 
shown  at  A;  the  tapered  end  with  key,  nut,  and  lock  nut,  as  shown  at 
B;  and  the  method  of  bolting  to  a  circular  flange  integral  with  the 
crankshaft,  as  indicated  at  C.  The  first  is  widely  used  for  stationary 
gas  and  marine  engines  of  very  low  price,  but  very  little,  if  at  all,  on 
automobile  engines.  The  second  has  been  used,  but  is  rapidly  going 
out,  as  it  is,  like  the  first,  a  low-priced  method  which  did  not  prove 
satisfactory.    The  third  method  is  rapidly  becoming  universal. 

In  use,  the  flywheel  flange  on  the  crankshaft  is  generally  five 
•  or  six  inches  or  a  figure  between  these,  in  diameter,  with  six  to  ten 
bolts.  In  the  form  shown  at  C,  Fig.  245,  the  flange  is  exterior  to  the 
fly-wheel,  but  in  Figs.  217  and  223,  the  more  general  method  of  grooving 
the  fl^-wheel  hub  to  receive  the  flange  will  be  noted.  In  Fig.  245, 
the  bolt  shown  has  a  countersunk  head  let  into  the  flywheel  surface; 
in  general,  the  bolt  head  is  either  standard  or  else  round  and  set  into  ar 
countersink.  In  this  case,  it  is  slotted  for  a  screwdriver.  Also  a 
single  nut  is  shown,  whereas  a  nut  and  lock  nut,  or,  at  least,  nut  and 
lock  washer,  are  always  used. 

Flywheel  Markings.  As  has  been  noted  previously  under 
Valves  and  Valve  Timing,  the  surface  or  rim  of  the  flywheel  generally 
carries  upon  it  marks  to  indicate  to  the  repair  man  the  timing  of  the 
motor.  Some  makers  give  only  one  or  two  marks  for  a  single  cylinder, 
reasoning,  with  some  degree  of  correctness,  that  if  the  first  cylinder 
is  set  right,  the  others  must  be  pretty  nearly  so,  and  that  more  marks 
would  only  confuse.  Others  put  on  their  flywheel  all  the  marks  for 
all  the  cylinders. 

Summary  of  Engine-Qroup  Treatment.  In  Parts  I,  II,  and  III, 
the  entire  engine  group  has  been  discussed  in  detail.  The  different 
sections  have  been  handled  according  to  present  practice  and  methods 
of  operation.  It  is  easily  possible  that  the  near  future  may  bring 
about  the  elimination  of  one  or  more  of  these  groups  or  its  combina- 
tion with  some  other. 

The  engine,  too,  has  been  discussed  in  its  present  form  only, 
although  some  attempts  have  been  made  here  and  there  to  rndxeaXi^ 


340  GASOLINE   AUTOMOBILES 

the  trend  of  developments.  He  would  be  a  very  foolish  man  who, 
knowing  the  past  history  of  the  automobile  engine,  would  say  that  it 
has  now  reached  perfection  and  will  alwaj'3  have  its  present  form. 
On  the  contrary,  there  seems  every  reason  to  believe  that  hardly  a 
single  feature  of  our  present-day  engine,  at  least  in  its  present  form, 
will  be  found  in  the  up-to-date  engine  of  ten  or  twenty  years  from 
now.  This  constant  change  renders  a  work  of  this  kind  aItno?t 
impossil)!^  of  absolute  up-to-dateness,  for  changes  are  actually  made 
and  put  into  use  while  the  book  is  being  printed.  As  far  as  possible, 
however,  the  work  aims  to  discuss  the  modern  developments  and  yet 
to  give  the  repair  man,  in  particular,  the  information  he  needs  as  he 
conies  in  contact  with  cars  of  all  classes,  ages,  and  conditions. 

SUMMARY   OF   INSTRUCTIONS 
VALVE  SUB-GROUP 
Valves 
Q.     For  what  purposes  are  valves  used? 

A.  \'aivfs  art'  used  (1)  to  admit  the  niLvtiu*  created  in  the 
{■arbnretiir  into  the  cylinders  at  the  proper  time  in  the  stroke  and  in 
till'  j>rn|>frqii!iiitity  (called  admission  or  iidet  valves);  and  (2)  to  allovr 


GASOLINE  AUTOMOBILES  341 

A.  Because  the  operation  of  opening  and  closing  the  valvea 
comes  on  every  other  stroke- only,  and  the  camshaft  really  works 
twice  as  slowly  as  the  crankshaft. 

Q.    What  is  the  general  form  of  a  valve? 

A.  The  usual  form  is  called  a  poppet  valve,  and  its  section  is 
that  of  a  letter  T,  having  a  long  slender  stem  at  the  top  of  which  is  a 
large  flat  head.  The  lower  surface  of  this  head  is  machined  off  to 
fit  the  seat  in  the  cylinder,  while  the  upper  surface  is  rounded  up  to 
the  center,  where  a  slot  for  a  screwdriver  is  provided. 

Q.    Are  there  other  forms  of  valves? 

A.  The  piston  form  of  valve  is  little  used,  but  the  sliding-sleeve 
valve  is  used  on  all  Knight  t^pe  of  engines  and  some  others.  In  addi- 
tion, a  few  motors  have  been  built  with  rotating-disc  valves.  The 
piston  valve  is  similar  to  the  usual  piston,  having  a  reciprocating 
motion  in  a  special  round-valve  chamber  made  for  this  purpose.  In  its 
movements  up  and  down,  it  uncovers  ports  in  the  walls,  thus  giving 
the  equivalent  of  the  poppet-valve  opening.  The  sliding  sleeve  is  a 
hollow  cylindrical  member  entirely  surrounding  the  piston  and  recip- 
rocating in  the  same  manner.  In  its  up-and-down  motions,  ports  in  it 
register  with  ports  in  the  cylinder  walls  at  the  proper  points  in  the 
cycle,  thus  corresponding  to  the  opening  of  the  poppet  valve.  The 
rotating-disc  valve  acts  on  the  same  plan  but  consists  of  a  flat  or 
a  conical  disc  which  is  gear-driven  from  the  crankshaft.  It  has  a  hole, 
or  port,  in  it  which  registers  with  other  ports  in  the  cylinder  at  the 
correct  time  in  the  cycle.  There  are  other  forms  of  valve  but  none 
in  wide  use. 

Q.    What  are  the  advantages  of  the  poppet  valve? 

A.  Its  simplicity  is  its  greatest  asset.  The  poppet  valve  is 
the  simplest  and  most  easily  understood  form  of  all.  In  addition,  it 
will  withstand  continuous  operation  at  the  highest  temperatures. 

Q.    What  are  its  disadvantages? 

A,  It  affords  a  comparatively  small  opening,  smallest  at  the 
beginning  and  ending  of  the  suction  stroke,  where  it  should  be  largest; 
it  has  a  noisy  hammering  action  which  makes  for  rapid  wear,  constant 
adjustment,  and  frequent  renewal;  the  actual  seat  is  so  small  and  is 
exposed  to  such  variations  of  temperature  and  other  severe  conditions 
that  it  tends  to  wear  out  and  leak  very  rapidly,  thus  reducing  the 
power  and  speed,  rendering  action  uncertain  and  calling  for  fret^uent 


342  GASOLINE  AUTOMOBILES 

regrinding;  finally,  the  necessity  for  ready  accessibility  for  adjusbaent 
allows  the  driver,  or  operator,  to  alter  the  action  with  8  consequ^it 
influence  upon  the  output. 

Q.    Can  any  of  the  disadvantaKes  be  overcome? 

A.  The  opening  cannot  be  changed,  but  the  noise  can  be  teduced 
by  enclosing  the  whole  valve  action  in  removable  covers.  The  influ- 
ence of  hammering  in  the  way  of  wear,  need  for  adjustment,  renewal, 
leakage,  etc.,  can  be  minimized  by  the  use  of  tungsten  ateel,  which  is 
harder  and  wears  much  more  slowly.  The  use  of  this  material  also 
lessens  power  and  speed  losses,  uncertain  actiqn,  and  frequen<y  of 
regrinding. 

Q.    Is  there  any  way  in  which  the  design  can  hifluence  these? 

A.  Itecent  tendencies  and  experiments  have  shown  that  with  an 
arrangement  for  positive,  or  mechanical,  closing  of  the  valve,  springs 
can  be  made  very  small  and  weak,  thus  eliminating  the  cutting 
action  of  the  usual  stiff  spring  on  the  cams  and  reducing  the  ham- 
mering action  and  the  noise. 

Q.    Have  sleeve  valves  any  springs? 

A.  No.  They  are  operated  by  eccentrics  from  the  eccentrie 
shaft,  which  corresponds  to  the  camshaft  in  a  poppet-valve  syston. 


GASOLINE  AUTOMOBILES  343 

ien  as  long  as  possible,  this  sometimes  overlapping  the  inlet  opening 
id  always  passing  the  upper  dead  center. 

Q.    What  is  the  average  valve  timing? 

A.  The  timing  of  fifty-six  American  motors,  including  perhaps 
le  hundred  different  models,  averaged  as  follows:  inlet  opened  from 
>per  dead  center  to  21®  beyond — average  10®  48';  inlet  closed  from 
®  to  46®  22'  beyond  lower  dead  center — average  35®  7';  exhaust 
»ened  from  31®  to  57®  30'  ahead  of  lower  dead  center — average  50®  10'; 
haust  closed  from  upper  dead  center  to  21®  beyond — average  9®  20'. 

Q.    How  does  the  repair  man  know  what  the  correct  timing  is? 

A.  Practically  all  makers  give  it  in  their  instruction  books  and 
her  literature  as  well  as  marking  it  upon  the  fl^^'heel  surface. 

Cams 

% 

Q.    How  are  the  cams  usually  made? 

A.  On  all  the  better  motors,  the  cams  are  formed  integral  with 
e  camshaft,  which  is  machined,  hardened,  and  ground  as  a  unit, 
li^  keeps  the  timing  always  the  same,  which  is  sometimes  not  the 
se  when  cams  are  made  separate  and  keyed  and  pinned  in  place, 
oreover,  the  integral  cams  are  more  accurate,  because  the  machines 
lich  have  been  developed  for  this  purpose  insure  absolute  accuracy. 

Valve  Guides 

Q.    What  is  the  valve  guide? 

A.  That  member  which  forms  the  bearing  as  well  as  the  support 
r  the  valve  stem.  Its  importance  can  be  judged  from  the  fact  that 
e  guide  holds  the  valve  in  line  with  its  seat  so  that  it  seats  itself 
curately. 

Q.    How  are  valve  guides  usually  made? 

A.  Generally,  they  are  of  cast  iron  and  removable,  being 
rewed  into  the  cylinder  from  below.  The  diameter  is  made  as  small 
possible  and  still  give  sufficient  stiffness  and  strength;  the  length  is 
ide  as  great  as  possible,  for  the  entire  length  of  the  valve  guide 
bearing  surface  for  the  valve  stem. 

Exhaust  Manifold 

Q.    What  is  the  influence  of  the  exhaust  manifold? 

A.  To  remove  the  exhaust  gases  from  all  cylinders  as  quickly 
d  as  thoroughly  as  possible.    If  this  is  not  done,  the  burned  gases 


344  GASOLINE  AUTOMOBILES 

will  retard  the  next  outflow  of  gas,  until  finally  the  engine  may  be 
stopped  because  it  is  not  receiving  rich  enough  fuel.  The  best  fonn 
of  exhaust  manifold  is  the  one  which  does  this  work  most  quickly  and 
most  thoroughly. 

Q.     What  is  its  genera)  form? 

A.  \  long  cHst-iron  member  of  round  or  rectangular  section, 
slightly  hirger  at  iIk'  millet  end,  and  bolted  to  the  cylinder  casting. 

Q.     How  can  this  be  improved? 

A.  Recent  experiments  have  shown  that  an  arrangement  of 
shape  and  size  can  be  effected  which  will  bring  about  an  ejector  effect 
immediately  back  of  each  exhaust  orifice.  This  will  produce  a 
slight  su<'tion  upon  each  succeeding  \olume  of  burned  gas,  which  will 
increase  the  efficiency'  of  the  exhaust  and  thereby  improve  the  power 
of  its  motor. 


Q.  '  What  is  the  purpose  of  the  muffler? 

A.  Til  rfdiK'c  the  pressure  of  the  exhaust  gases  so  that  when 
enLtTf;iiig  into  the  .Ltiiiusjihcre  they  will  do  this  without  noise.  As 
tlicy  eiruTp'  fnniL  the  cylinders,  the  pressure  is  fairly  high,  and  if  they 


GASOLINE  AUTOMOBILES  345 

Q.    What  Is  the  general  cooling  method? 

A.  There  are  two  methods  in  general  use,  called  the  natural, 
or  thermosiphon,  and  the  pump  systems.  The  former  is  so-called 
because^the  natm^l  increase  in  temperature  of  the  water  is  used  to 
circulate  it  to  the  radiator  and  back.  The  latter  is  called  a  pump 
system,  because  a  pump  is  used  to  force  the  water  around. 

Q.    Are  there  other  differences  between  the  two? 

A.  In  the  thermosiphon  system,  the  difference  in  pressure  oea- 
ted  by  the  increasing  temperature  is  so  slight  that  all  bends  must 
be  made  very  easy  and  all  pipes  made  very  large,  so  the  water  will 
pass  easily.  Also  the  system  as  a  whole  must  be  short  and  compact 
with  radiator  close  to  motor,  and  with  little  difference  in  level  between 
the  highest  and  lowest  points.  The  added  weight  of  larger  pipes  and 
their  appearance  just  about  balance  the  simplicity  and  smaller  number 
of  parts. 

Q.    What  general  types  of  radiators  are  in  use? 

A,  The  cellular  (which  may  have  square,  round,  or  hexagonal 
cells)  and  the  tubular  form  with  horizontal  fins  sweated  on  are  the 
two  forms  generally  used. 

Q.    How  does  the  water  circulate  in  these  two  forms? 

A.  In  the  cellular  form  the  water  is  in  very  thin  sheets  between 
the  cells,  with  a  consequently  high  ratio  of  air  space  to  water  space. 
The  water  is  forced  to  follow  a  zigzag  path  to  add  to  the  cooling  effect. 
In  the  tubular  form,  the  water  flows  from  an  upper  to  a  lower  tank ' 
through  the  vertical  tubes,  which  are  of  relatively  larger  diameter  as 
compared  with  the  water  space  in  the  cellular  form — |  against  ^. 

Q.    What  is  the  usual  form  of  pump? 

A.  Four  forms  of  pumps  are  used  for  water  circulation:  the 
centrifugal,  the  gear,  the  plunger,  and  the  vane.  The  first  two  are 
used  about  equally  on  the  majority  of  American  pleasure  cars,  the 
last  two  having  but  a  few  adherents. 

Q.    What  is  the  latest  move  to  improve  water  circulation? 

A,  The  use  of  a  thermostat  to  control  the  flow  of  the  water 
according  to  its  temperature.  This  device  holds  the  water  in  the 
c^'linders  until  a  certain  predetermined  temperature  is  reached,  when 
it  opens  and  allows  the  water  to  flow  through  the  radiator  and  be 
cooled.  By  setting  this  so  that  this  predetermined  temperature  is 
fai^,  but  not  so  high  as  to  be  dangerously  close  to  the  boiling  point. 


346  GASOLINE  AUTOMOBILES 

the  efficiency  of  the  engine  is  increased,  for  a  hot  engine  works  better 
than  a  cold  one  and  gives  more  power. 

Q.    What  is  the  purpose  of  the  fan? 

A.  To  increase  the  efficiency  of  the  radiator  by  drawing  more 
air  through  it  and  thus  cooling  the  water  more. 

Q.    How  is  the  fan  generally  driven? 

A.  The  belt  drive,  using  a  flat  or  V-type  belt  is  general  because 
of  its  simplicity,  but  a  few  better  cars  have  gear  or  chain  drive; 
the  latter  method  has  increased  in  recent  years  particularly  with  the 
V-type  motors,  for  in  those  it  has  been  found  easy  to  drive  the  fan  from 
a  shaft  in  the  immediate  vicinity. 
Questions  for  Home  Study 

1 .  Describe  in  detail  the  timing  of  the  Knight  motor. 

2.  Tell  how  to  regulate  and  check  up  the  valve  action  from  the 
flywheel  marking. 

3.  How  are  silent-chain  camshaft  drives  adjusted?  How  are 
gears? 

4.  How  is  the  valve-stem  clearance  adjusted? 

LUBRICATION  SYSTEMS 

Q.    What  is  meant  when  lubrication  is  referred  to? 

A.  In  general,  the  lubrication  of  the  engine,  because  that  is  so 
much  more  important  than  the  lubrication  of  any  other  part  or  group 
of  parts.  If  the  engine  is  run  without  lubricant,  even  for  a  very  short 
time,  it  is  ruined.  On  the  other  hand,  many  of  the  car  parts  can  be 
run  without  lubricant  for  days  and  days,  yet  no  damage  will  result. 

Q.  What  are  the  most  used  systems  for  the  internal  oiling  of 
the  engine? 

A.  The  most  used  systems  are,:  the  splash,  the  pressure,  and  a 
combination  of  the  two,  known  as  the  splash-pressure,  or  constant- 
level,  system.  The  first  is  simple,  oil  being  provided  in  troughs  into 
which  the  connecting  rods  dip,  thus  spreading  the  oil  all  over  the 
interior  of  the  motor  and  lubricating  ever\i:hing.  The  pressure  sys- 
tem forces  oil  under  pressure  to  all  the  important  bearings  and  surfaces 
by  means  of  interior-drilled  oil  leads  or  special  pipes.  It  requires  a 
pump,  driven  from  some  engine  shaft,  one  or  more  strainers  (for  the 
oil  is  used  over  and  over),  the  special  drilling  or  piping,  a  gage  on  the 
dasb  to  tell  the  driver  how  the  system  v&  "v? oxVk^^^  «xA  \si  ^«gbm6  oBses 


GASOLINE  AUTOMOBILES  347 

an  adjustable  pressure  valve.  The  splash-pressure  form  has  the  oil 
leads  to  the  important  points  only.  Then  the  excess  runs  down  into 
the  crankcase  and  fills  troughs  into  which  the  connecting  rods  dip.  ' 
In  some  cases,  these  troughs  are  filled  by  direct  individual  leads  off 
of  the  main  oil  pipe.  Then  when  the  rods  dip  into  the  oil,  all  benefits 
of  the  splash  system  are  obtained.  The  fact  that  the  pump  main- 
tains a  constant  level  of  oil  in  the  troughs  has  led  to  calling  this  the 
constant-level  system. 

Q.    What  pressure  is  used  in  the  pressure  system? 

A.  Prior  to  the  introduction  of  V-t^T^e  and  high-speed  motors, 
a  few  pounds  less  than  5  was  considered  sufficient.  Now,  many 
motors  have  a  system  which  works  under  40,  50,  60,  and  even  70 
pounds  pressure.  The  oil  leads  are  smaller,  but  the  amount  of  lubri- 
cant which  the  bearing  receives  is  much  greater  than  previously. 

Q.    What  is  the  external  lubrication  of  the  motor? 

A.  The  lubrication  of  the  accessories,  such  as  magneto,  water 
pump,  starting  motor,  generator,  air  pump,  fan,  etc.  Practically 
all  these  have  oil  holes,  oil  cups,  or  grease  cups.  The  last  named  must 
have  a  special  heavy  grease  or  pure  mutton  or  beef  tallow,  as  a  thick 
lubricant  is  needed  to  resist  the  passage  of  the  water  and  not  wash 
away.  Otherwise  the  external  lubrication  is  fairly  simple  and  requires 
little  attention. 

Q.    What  are  the  most  used  types  of  oil  pumps? 

A.  Like  the  water  pump,  all  forms  are  used  but  the  most  popu- 
lar are  the  cam-operated  plimger,  the  gear,  and  the  plunger. 

Q.    How  are  these  driven? 

A.  By  gear  from  any  convenient  shaft,  as  camshaft,  crankshaft, 
water-pump  shaft,  magneto  shaft,  etc.  When  the  pump  is  enclosed 
in  the  crankcase,  it  is  almost  invariably  driven  from  one  of  the 

camshafts. 

Q.    How  are  other  parts  of  the  car  lubricated? 

A.     Aside  from  clutch,  transmission,  rear  axle,  and  wheels,  prac- 

tically  all  parts  are  lubricated  by  means  of  grease  or  oil  cups  or  ^oil 

holes*     The  latter  are  rapidly  being  eliminated  for  the  sake  of  clean- 

UnesS' 

Q^     What  are  possible  future  developments  in  oiling? 

A       At  present,  there  are  two  tendencies  noticeable,  one  being 

jct/^nslon  of  fprced  lubrication  to  many  parts  outside  the  engine. 


348  GASOLINE    AUTOMOBILES 

In  the  case  of  the  Fergus  car,  tlie  springs  are  enclosed  in  leather  ImxiIs 
and  lubricant  supplied  from  the  engine  oil  purnp.  Siinilariy,  clutch 
and  transmission  are  oiled  from  the  engine  pressure  system.  The 
I9I7  Marmon  car  is  claimed  to  have  but  four  or  five  lubricant  points 
outside  of  the  engine  system.  Another  maker  has  adopted  the 
leather-enclosed  and  lubricated  springs.  All  these  signs  point  toward 
less  lubrication  for  the  dri\'er  and  owner  to  do,  more  points  being 
included  in  the  engine  system.  The  other  noticeable  point  mentioned 
has  been  partially  covered;  it  is  the  reduction  in  number  of  points 
requiring  individnal  attention,  by  other  means  than  extending  the 
engine  pressure  syiiteni  to  them. 

Q.     How  should  graphite  be  used? 

A.  Graphite  shuuld  be  used  very  sparingly,  for  a  little  of  it  goes 
a  long  way.  It  is  not  like  grease  which  is  used  up  very  quickly,  but 
ia  more  or  less  indestructible.  'When  a  combination  of  graphite  and 
grease  is  use«l,  it  will  lie  found  to  last  twice  as  long  at  any  given  point 
as  the  same  quality  of  grease  alone.  Graphite  in  its  very  finest  form, 
when  introduced  into  the  engine  system,  is  beneficial  as  it  seems  to 
put  a  kind  of  polish,  or  surface  finish,  on  the  cylinders,  which  resists 
wear.     After  tliis  liiis  been  put  on,  less  lubricant,  by  at  least  20  per 


GASOLINE   AUTOMOBILES  349 

2.  How  is  the  Cadillac  eight  motor  oiled?    Give  details. 

3.  What  is  the  usual  method  of  changing  the  amount  of  oil 
pumf>edy  in  a  pressure  system? 

4.  Select  some  method  of  driving  the  oil  pump,  which  seems 
simple  to  you,  and  describe  it,  telling  why  you  selected  it. 

5.  How  would  you  lubricate  spring  leaves,  with  what  and  how 
often?  fan  bearings?  front  wheel  bearings?  magneto  shaft? 
differential? 

6.  How  do  you  select  a  good  engine  oil? 

FLYWHEEL  QROUP 

Q.    How  does  a  light  flywheel  affect  an  engine? 

A.  The  engine  will  be  easy  enough  to  start  and  stop,  but  very 
touchy  on  changing  speeds — too  quick  a  change  will  kill  it.  More- 
over, it  will  not  run  very  slowly. 

Q.  How  do  present  flywheel  sizes  compare  with  those  of  former 
years? 

A.  Present  fl^'wheels  are  larger  in  diameter  but  narrower  and 
lighter  in  weight.  The  increase  of  diameter  made  by  the  elimination 
of  subframes  allowed  cutting  down  the  width  and  weight  because  the 
flj'wKeel  effect  is  equal  to  its  mass  times  its  radius,  so  that  by  increas- 
ing the  radius  the  mass  can  Ik»  reduced. 

Q.    What  are  the  usual  methods  of  flywheel  fastening? 

A.  The  flange  forged  on  the  crankshaft  and  through  bolts  is 
almost  universal.  A  few  niotors  are  still  made  with  a  round  crank- 
shaft end  and  a  large  key;  or  with  a  tapered  shaft  end,  and  a  key,  a 
nut,  and  a  lock  nut.  The  latter  form  is  used  when  the  crankcase  is  of 
the  barrel  type  with  removable  end  plates  and  is  so  made  as  to  allow 
removal  of  the  crankcase  end  plate  at  the  rear.  In  some  few  cases 
the  flv^wheel  is  made  this  way  so  as  to  allow  putting  on  or  taking  off 
a  ball  bearing  at  the  rear  end  of  the  crankshaft. 

Q.    What  are  the  mitrkings  on  the  flywheel  rim? 

A.  The  timing  is  now  generally  marked  on  the  surface  of  the 
flwheel  to  guide  the  owner  or  repair  man  in  making  adjustments  or 
in  assembling  the  engine  correctly.  The  adjustments  vary;  some 
makers  give  the  complete  timing  for  a  singk*  cylinder,  others  give  a 
few  points  for  all,  and  still  others  give  all  the  points  for  all  the  cylin- 
ders.   The  latter  is  the  l)est  way. 


GASOLINE  AUTOMOBILES 


PART  IV 


CLUTCH  GROUP 

TYPES  OF  CLUTCHES 

Classification.  Principal' among  the  indispensable  parts  inter- 
filing betweerTengine  and  road  wheels,  and  one  which  may  be  a 
urce  of  great  joy  or  correspondingly  great  wrath,  according  to 
bether  it  be  well  or  poorly  designed  and  fitted,  is  the  clutch.  There 
e  six  forms  into  which  clutches  may  be  divided,  although  not  all 
them  are  in  general  use  in  the  automobile.  Only  the  first  four  are 
idely  used  on  automobiles.    These  different  forms  are: 

(1)  Cone  clutches 

(2)  Contracting-band,  or  drum,  clutches 

(3)  Expanding-band,  ring,  clutches 

(4)  Disc  and  friction  clutches 

(5)  Hydraulic,  or  fluid,  clutches 

(6)  Magnetic,  or  electric,  clutches 

The  necessity  for  a  clutch  lies  in  the  fact  that  the  best  results 
•e  obtained  in  an  automobile  engine  when  run  at  constant  speed. 

1  as  much  as  the  speed  of  the  oar  cannot,  from  the  nature  of  its  use, 

2  constant,  it  requires  some  form  of  speed  variator.  This  is  the 
3ual  gear  box,  or  transmission,  but?  in  addition,  there  is  the  necessity 
f  disconnecting  it  from  the  motor  upon .  starting,  since  the  engine 
mnot  start  under  a  load.  There  is  also  the  necessity  for  disconnect- 
ig  the  two  when  it  is  desired  to  change  from  one  speed  to  another 
ther  by  way  of  an  increase  or  a  decrease.  So,  also,  when  one  wishes 
>  stop  the  car,  there  must  be  some  form  of  disconnection.  There 
re,  then,  three  real  and  weighty  reasons  for  having  a  clutch. 

Requirements  Applying  to  All  Clutches.  In  a  serviceable  clutch 
lere  are  two  general  requirements  which  are  applicable  to  all  forms, 
hese  are  gradual  engagement  and  large  contact  surfaces,  although 
le  latter  requirement  may  be  made  to  lose  much  of  its  force  by 


GASOLINE  AUTOMOBILES 


making  the  surfaces  very  efficient.  In  the  cone  dutch,  gradual 
engaging  qualities  are  secured  by  placing  a  series  of  flat  springs  under 
the  leather  or  clutch  lining.  By  means  of  these  springs,  acting  against 
the  main  clutch  spring,  the  clutch  does  not  grab,  since  the  large 
spring  must  have  time  in  which  to  overcome  the  numerous  small 
springs.  In  this  way,  the  engagement  is  gradual  and  the  progress  of 
the  car  is  easy  as  well  as 
continuous.  I 

The  specific  neces- 
sity in  a  cone  olutdl, 
whether  it  be  direct  or 
inverted,  is  atwofoldo 
— sufficient  friction  sur- 
face and  proper  angu- 
larity. The  latter,  in  a 
waj",  affects  the  former, 
as  will  be  discussed  more 
in  detail  later.  The  an- 
gularity varies  in  practice 
from  S  to  18  degrees. 


GASOUNE  AUTOMOBILES 


353 


end  to  engage  it.    This  is  called  the  inverted,  or  sometimes  the 
reversed,  cone  clutch. 

A  great  disadvantage  of  the  inverted  form  is  that  the  spring  must 
be  carried  between  the  two  cones,  which  means  that  it  is  inside  where 
it  cannot  be  reached  for  adjustment.  This  form  causes  trouble  in 
assembling  because  the  male  cone  must  be  put  in  place  with  the 
spring  between  it  and  the  fl;T\'heel  before  the  female  can  be  set  into 
its  place  and  bolted  up.  These  two  big  sources  of  trouble  have  caused- 
designers  to  turn  to  the  direct  tjpe  more  freely,  as  it  lends  itself 
readily  to  an  external 
adjustment.  If  the  spring 
is  outside,  it  is  easily  put 
into  place  and  as  easily 
taken  out. 

An  e-xcellent  exam- 
ple of  the  direct  cone 
clutch  is  seen  in  Fig.  240, 
which  shows  the  Stude- 
baker  clutch  in  section. 
The  noticeable  point 
about  this  clutch  is  its 
simplicity.  It,  will  be 
noted  that  the  spring  is 
entirely  enclosed,  so  that 
when  it  needs  adjusting 
the  repair  man  must 
open  the  universal  jomt 
and  operate  the  bolt  A  which  regulates  tlie  tension  of  the  spring. 

Another  good  example  of  the  simplicity  of  the  cone  clutch  is  seen 
in  Fig.  247,  which  is  an  aluminum  member  with  bosses  cast  for  cork 
inserts.  Between  the  inserts  may  be  seen  the  fiat  heads  of  the  copper 
rivets  which  hold  the  clutch  facing  in  place.  Obviously,  this  has  the 
same  disadvantage  of  internal,  and  thus  inaccessible,  spring. 

In  the  cone  type  of  clutch,  shown  in  Fig.  248,  the  inaccessible 
spring  is  avoided.  In  addition,  a  number  of  small  springs  are  used  in 
place  of  one  very  large  and  very  stiff  one.  The  ease  of  adjustment 
and  the  greater  ease  in  handling  the  springs  make  this  clutch  a  much 
better  design  for  average  use  from  the  repair  man's  point  of  view. 


354 


GASOLINE  AUTOMOBILES 


An  example  of  the  inverted-cone  type  is  shown  in  Fig.  249,  whidi 
shows  the  clutch  on  the  four-cylinder  Steams- Knight,  This  tj-pe  hu 
an  o<id  number  of  small  springs  equalI^''  spaced  around  the  clutbh, 
but  these  cannot  be  adjusted  from  the  outside. 

Contracling-Band  Clutch.  A  short  consideration  of  the  band 
at>  le  (if  clutch  shows  that  this  does  not  differ  radically  from  the  an& 
nat>~  band  brake,  either  in  construction,  application,  or  actual  work' 
_^     I  ing.    The  difference  in  the 

*'-jMa)  two  lies  in  the  fact  that  the 

'^■,      i^3l/  band,  as  a   clutch,   b  dfr 

.  -y. — P^s  signed   to   transmit    pi>wer 

y>^    — '■'I  .fc;^^yy^  with  as  little  loss  as  possi- 

ble, while  the  band  as  ft 
brake  is  designed  to  absorb 
the  forward  energy  of  ft! 
raovTng  vehicle  In  the  short- 


GASOLINE  AUTOMOBILES 


of  the  clutching  lever,  while  the  other  end  of  the  band  is  fastened  to 
the  middle  of  this  lever.  The  clutching  pull  comes  upon  the  upper 
extremity  of  the  lever.  Then  the  band  acts  to  aid  in  clutching  itself, 
i.e.,  a  scissors  action  is  obtained,  and  the  required  pull  is  lessened. 

This  construction  can  be  seen  quite  plainly  in  Fig.  287,  which 
shows  the  planetary  transmission  anti  bands  used  nn  Ford  cars.  In 
this,  the  low-  and  reverse-speed 
bands  are  shown  in  full.  This 
is  of  particular  interest  as  Mr. 
Ford  is  now  the  only  American 
maker  using  the  planetary  form 
of  transmission,  all  other  makers, 
even  of  very  low-priced  machines 
— some  below  the  Ford  price — 
having  gone  to .  the  selective 
sliding-^ar  form. 

Expandtng-Band,  or  Ring, 
Clutch.  The  expand  ing-band 
clutch  finds  favor  among  few. 
Like  the  contracting  band,  which 
is  very  similar  to  the  band  form 
of  brake,  the  expanding  band  is 
much  like  the  expanding  tj-pe  of 
brake,  except  that  the  clutch  is 
used  to  form  the  connection  be- 
tween two  rotating  parts.  Viewed 
from  the  standpoint  of  pure 
engineering,  the  expanding  band 
is  little  different  from  the  cone 
type  of  clutch,  granting  that  the 
angularity  of  the  operating  cam 
is  the  same  as  that  of  the  cone. 

Much  depends  upon  how  the  band  is  expanded.  This  expansion 
is  usually  accomplished  by  means  of  screws,  which  may  be  either 
right-handed  or  left-handed  or  both. 

Another  form  is  expanded  by  a  double-threaded  screw  operated 
by  a  lever.  The  lever,  in  turn,  is  moved  by  a  pair  of  sliding  collars  on 
the  miun-clutch  shaft,  the  clutch  foot  pedal  moving  theae  fow«.T4. 


FiC     249      lDv<rt«d    Cone   Ctutob    Uied    an 

SteHriW'KiUBht  Four-Cylinder  Can 

CmrUtii  of  F.  B.  Sttarnt  Company, 

CttrOand,  Okio 


356  GASOLINE  AUTOMOniLKS 

Disc  Clutch.  With  its  iidvent  in  1904,  the  muItiple-diRC  dutch 
has  steadily  grown  in  popularity,  until  t^xla.v  it  is  looked  upon  us  the 
most  satisfactory-  solution  of  the  diffirult  clutch  problem.  Designers 
who  have  once  adopted  it,  seldom,  if  ever,  go  l)at'k  to  aiiotlier  form, 
while  of  the  new  cars  coming  out  from  time  to  time  nearly  three- 
fourths  are  equipped  with  some  form  of  disc  clutch. 

Popularity  Compared  with  Other  Fonm.  Statistics  for  I9K 
showed  that  the  disc  form  of  clutch  was  easily  the  most  ixipular  type. 
Of  2.10  different  chassis  for  1914,  I19wereequipped  with  disc  clutches, 
97  with  the  cone,  9  with  a  contracting-hand  tj-pc,  and  but  5  witli  an 
expand ing-band  f()mi.     The  relative  figures  for  \9H>  were  about  94 


GASOLINE  AUTOMOBILES 


357 


as  can  the  outside  spring  of  the  disc.  An  interesting  point  in  this 
connection  is  that  the  transmissions  also  are  interchangeable,  although 
the  type,  Fig.  252,  with  roller  bearings  is  intended  for  a  moderately 
heavy  passenger  car,  while  that  in  Fig.  251  is  foj  lighter  work. 

Simple  Types.  The  simple  tj-pes  differ  in  number  and  shape  of 
discs,  method  of  clutching,  material,  and  lubrication;  but  in  principle 
all  are  alike.  This  clutch  is  one  in  which  the  flat  surfaces  properly 
pressed  together  will  transmit  more  power  with  less  trouble  than  any 


other  form.  By  multiplying  the  number  of  surfaces  and  making 
them  infinitely  thin,  the  power  transmitted  may  be  increased  indefi- 
nitely. That  this  is  not  idle  fancy  is  shown  by  a  number  of  very 
successful  installations  of  1000  horsepower  and  over  in  marine  service. 
The  minimum  number  of  plates  in  use  is  said  to  be  three,  but 
very  often  the  construction  of  a  three-plate  clutch  is  such  that  one  or 
two  surfaces  of  other  parts  are  utilized,  making  it  a  two-  or  even  one- 
plate  clutch  in  reality.  In  the  Warner  clutch,  shown  in  Fig.  252, 
there  are  really  but  two  clutching  surfaces,  the  face  of  the  inner  plate 


GASOUNE  AUTOMOBILES 

against  the  flyn'heel  and  the  outer  face  agunst  the  engapng  dbc. 
Both  plates  are  faced  with  suitable  friction  surface  but  it  really  is  a 
one-disc  clutch. 

Multiple-Disc  Clutches.  Tie  modem  tendency  in  disc  clutches, 
however,  is  away  from  those  of  few  plates  requiring  a  very  hi^ 
spring  pressure — since  the -friction  area  is  ,  necessarily  limited— 
toward  the  multiple-disc  variety,  in  which  a  very  large  area  b 
obtained.    The  large  area  needs  a  very  light  spring  pressure,  and 


GASOLINE  AUTOMOBILES  359 

In  the  true  multiple-plate  clutch,  there  are  three  general  varieties 
met  with  in  practice:  the  metal-to-metal  with  straight  faces;  the 
metal-to-metal  with  angular  or  other  shaped  faces  designed  to 
increase  the  holding  power;  and  the  straight-face  kind  in  which  metal 
does  not  contact  with  metal,  one  member  either  being  lined  with  a 
removable  lining  or  fitted  with  cork  inserts. 

Melal-to-Metal  Dry-Disc  Type.  The  metal-to-metal  method  has 
the  additional  advantage  of  having  the  central  part  within  which  the 
clutch  is  housed  very  small  in  diameter,  so  that  the  portion  of  the  fly- 
wheel between  the  rim  and  the  clutch  housing  may  be  made  in  the 


form  of  fan  spokes  that  convert  it  into  a  fan  which  serves  to  cool  the 
motor  better. 

As  the  various  examples  of  disc  clutch  shown  would  indicate, 
the  designer  has  had  his  choice  between  a  few  large  discs  and  a  lai^ 
number  of  small  ones.  If  he  chose  the  former,  the  clutch  could  be 
housed  within  the  flj-wheel,  but  that  would  make  it  inaccessible.  If  he 
chose  the  latter,  the  clutch  could  not  be  kept  within  the  flywheel 
length.  A  separate  clutch  housing  would  be  a  necessity,  but  the 
clutch  could  be  made  accessible  and  flywheel  fan  blades  could  be  used. 

Another  example  of  the  plain  metal-to-metal  disc  clutch  is  shown 
in  Fig.  253.    In  this  case  also  the  clutch  is  not  housed  in  the  flywheel, 


360  GASOLINE  AUTOMOBILES 

as  in  most  of  the  preceding  examples  of  this  fonn  of  chitch,  but  in  the 
forward  end  of  the  tninsiiiission  case,  that  is,  instead  of  motor  and 
clutch  forming  a  unit,  the  clutch  is  a  unit  with  the  transmission.  I(  t» 
claimed  that  this  position  makes  it  more  accessible,  since  it  brings  tbs 
clutch  directly  under  the  floor  boards  of  the  <!river's  compartment 
where  it  can  be  lubricated  iietter.  The  lubrication  is  etfected  tlirougb 
communication  with  the  gear  part  of  the  case,  which  is  always  filled 
with  lubricant. 

In  the  figure  it  will  be  noted  that  there  are  13  driven  discs,  with 
keyways,  which  hold  them  to  the  driven  drum.  Note  that  the  dnim 
is  held  to  its  shaft  by  means  of  a  pair  of  large  set  screws.  The  clutch- 
ing springs  are  of  small  diameter  and  size,  space*!  etpially  around  the 
periphery  of  tlie  discs ;  each  disc  is  enclosed  in  a  small  and  thin  met*! 
casing.  Attention  is  called  also  to  the  universal  joint  shown.  This 
joint  forms  the  rear  end  of  the  driving  connection  with  th«  flywhed, 
which  will  be  refcrrefl  to  later.  These  discs  are  flat-stamped  out  of 
sheet  steel  with  tlie  proper  ke>-wa,va  for  internal  or  external  holdings. 

Use  uf  Faringn.  The  more  modem  di.-M"  clutch  has  two  sets 
of  sheet  metal  discs,  one  of  which  is  faced  on  one  or  both  sides  wiUi 
a  special  material.  Without  a  single  exception,  all  the  diac  ctutcbn 
ahnun  hnvP  hu-l  nlnir.  cli«^  n™in=t  r.!«in  /li«/-i      ThU  mnW™  »  ^imijt. 


GASOLINE  AUTOMOBILES 


361 


To  present  an  example  of  the  faced  t^-pe,  Fig.  254  shoe's  the 
multiple-disc  clutch  of  the  eight-cylinder  V-tjT*  Cadillac.  In  this 
illustration  the  eight  driving  discs  can  be  seen  with  the  facing  on 
each  side  of  each  one.  This  facing  is  of  wire-mesh  asbestos,  anrl 
between  each  pair  of  discs  comes  a  plain  driven  disc,  so  that  it  has  a 
facing  of  the  asbestos  against  each  side  of  the  metal  which  it  grips. 
The  keys  which  hold  and  drive  the  Inner  discs  can  be  seen  on  the 


end  of  the  housing,  while  the  slots  into  which  the  keys  project  can 
be  seen  on  the  discs.  By  examining  the  group  closely,  the  driven 
plain  discs  can  be  seen  between  each  pair  of  the  drivers.  The 
method  of  driving  these  discs  through  a  multiplicity  of  keys  and 
grooves  is  unusual,  but  it  is  a  good  example  of  Cadillac  thoroughness. 
Fig.  2.S4  also  shows  the  pedals  and  the  exterior  of  the  clutch  case 
where  it  bolts  up  to  the  engine.  This  indicates  how  a  unit  power 
plant  simplifies  the  control  group  and  eliminates  parts.       ' 


863 


CASOLINE  AUTOMOBILES 


Floaiing  Discs  a  Novelty.  The  cIutcK  on  Locomobile  ears, 
shown  in  section  in  Fig.  255,  is  very  much  like  the  Cadillac  just 
shown,  except  for  the  novel  featm-e  that  the  fabric  facings  are  not 
attached  either  to  the  driving  or  to  the  driven  discs  but  float  between 
them.  This  fabric,  u.-iually  a  woven  asbestos  material  with  a  central 
core  of  interwoven  metal  wires,  instead  of  being  attached  to  both 
sides  of  every  other  disc  or  to  one  side  of  every  disc,  is  not  attache! 
at  all.  The  rings  for  the  fabric  discs  are  made  up  in  the  form  of 
annular  rinfirs.    They  have  the  same  inner  diameter  as  the  inside  of  the 


GASOUNE  AUTOMOBILES  363 

The  discs  of  this  unusual  clutch  had  a  perfectly  flat  outer  portion 
and  B  conical  inner  portion,  only  the  latter  taking  part  in  the  trans- 
mission of  power.  In  this  disc  form,  then,  we  have'  the  advantage 
of  the  disc  economy  of  space,  together  with  the  advantages  of  the 
cone  clutch  and  the  additive  gain  of  running  in  a  bath  of  oil. 

Another  form  utilizing  this  principle,  and  one  that  is  more  widely 
used,  is  that  known  as  the  "Hele-Shaw"  so  named  from  its  inventor, 
the  famous  English  scientist,  Dr.  H.  S.  Hele-Shaw.  This  ia  essen- 
tially a  flat  disc,  as  shown  at  A,  Fig.  256,  with  a  ridge  B  at  about 
the  middle  of  the  friction  surface;  this  ridge  consists  of  a  portion 


Hele-Shaw  Diec  Clutch.  Showing  Cone  Surlu 


of  the  surface,  which  has  been  obtruded  during  the  stamping  process 
in  such  a  way  as  to  leave  the  surface  of  the  ridge  in  the  form  of  an 
angle  of  small  height.  The  angle  used  Is  35  degrees,  and  this  value  has 
been  determined  upon  experimentally  as  the  best.  Fig.  256  shows  a 
cross-section  through  au  assembled  clutch,  which  reveals  the  clutch 
angle  very  plainly.  In  use,  the  ridges  nest  one  on  top  of  the  other; 
and  in  the  extreme  act  of  clutching,  not  only  the  flat  surfaces  but 
both  sides  of  the  ridge  are  in  contact  with  the  next  plate.  Thus,  not 
only  is  the  surface  for  a  given  diameter  increased,  but  the  w^'^ 
shape  is  also  taken  advantage  of. 


364  GASOUNE  AUTOMOBILES 

UijdmnUc  Clutchen.  All  the  methoiia  of  engaging  an<i  dis- 
engaging the  engine  at  will,  aa  discussed  before,  have  been  of  » 
mechanical  nature.  The  hydraulic  clutch,  on  the  otlier  hand,  par- 
tjikes  more  of  the  fluid  nature,  although  it  is  operatwl  by  mechanical 
means.  Ordinarily,  it  is  in  the  nature  of  a  pump  with  a  by-pass, 
the  pump  working  at  ordinary  speeds  to  force  the  heavy  liquid, 
usually  glycerine,  through  the  hy-pas-i.  To  clutch  up  tightl>',  how- 
ever, the  by-pass  is  closed  and.  the  liquid  being  unable  to  circulate 
while  the  pump  continues  to  operate,  the  whole  device  is  rotated  as 
a  unit.  In  this  case  it  operates  just  as  tiny  other  clutch,  but,  due  to 
the  sluggish  action  of  the  fluid,  it  is  slower  to  respond.  Then,  t<». 
the  grave  question  of  leakage  is  always  present,  and  the  smallest  Imk 
puts  the  clutch  entirely  out  of  use.  These  disadvantages,  together 
with  the  necessary  complications,  have  retarded  the  development  (tf 
the  hydraulic  form  so  that  there  are  few  of  that  type  in  use  t<xiay. 

Magnetic  Clutch.  .-MI  the  foregoing  clutches  pn^sont  in  one 
form  ()r  another  \er\'  complicated  devices  for  freeing  the  transmission 
shaft  from  the  engiiie  shaft,  but  the  magnetic  clutch  is  a  device*  which 
has  simplicity  for  its    foremost  argument.     The    magnetic  clutch 


GASOLINE  AUTOMOBILES  365 

Accumulator  Company,  Chicago,  a  centrifugal  electric-generating 
clutch.  This  name  gives  a  little  clue  to  its  action,  which  is  that  of  a 
combination  of  the  usual  friction  clutch  and-  that  of  the  electric- 
magnetic  drag  between  armature  and  fields  of  any  electric  machine. 
In  addition  to  its  clutching  feature,  its  ability  to  drive  when 
partially  clutched  makes  it,  in  effect,  a  transmission,  so  that  it  is 
designed  to  replace  the  usual  clutch,  gearset,  flywheel,  electric  gen- 
erator, and  starting  motor,  it  is  composed  of  two  parts:  an  arma- 
ture, which  becomes  the  fiv-wheel;  and  a  field  mounted  on  the  pro- 
peller shaft.    The  former  carries  an  internal  commutator,  and  the 


lattercarriesbrushholderswhichholdbrushesagainst  the  commutator. 
These  brushes  are  mounted  so  that  the  centrifugal  force  of  rotation 
increases  the  force  with  which  they  press  against'the  commutator. 
Thus  there  is  a  variation  from  practically  no  contact  up  to  the  maxi- 
mum, at  which  point  the  centrifugal  force  is  so  great  that  field  and 
armature  revolve  as  a  solid  unit. 

This  construction  is  well  indicated  in  the  two  illustrations  of  this 
device,  Figs.  257  and  258.  Fig,  257  shows  the  field  unit  mounted  on 
the  propeller  shaft  in  which  F  is  one  of  six  field  poles,  B  ?.  bTMsiv,%.Tv^ 
C  one  of  the  collector  rings.    Fig.  258  is  an  external  v\e«  -^iVwii  ■^ty«* 


366  GASOLINE  AUTOMOBILES 

the  clutch  assembled.     In  this  illustration  the  brushes  B  are  shown 
pressed  out  against  the  commutator  by  the  centrifugal  force. 

An  automobile  built  in  France — the  Ampere — uses  the  electric- 
generating  clutch  construction  excluaivelj',  the  master  clutch  being 
dispensed  with  in  favor  of  an  individual-clutch  transmission.  The 
differential  is  dispensed  with,  and  in  its  place  a  pair  of  magnetic 
clutches — une  fur  each  wheel — are  used.    The  difl'erential  action  is 


GASOLINE  AUTOMOBILES 


367 


yhich  compresses  the  clutch  spring  or  springs  and  allows  the  clutch 
nembers  to  separate.  This  throws  the  clutch  out.  To  throw  it 
>ack  in,  remove  the  foot  pressure  from  the  pedal,  and  the  springs 
igain  exert  pressure  and  force  the  parts  together.  This  action 
»uses  them  to  take  hold.  Tliere  was  a  time  when  a  considerable 
lumber  of  cars  had  the  clutch  so  constructed  that  the  pedal  held  it 
n  and  the  springs  threw  it  out,  just  the  reverse  of  the  present  plan, 
rhis  method  is  no  longer  used,  as  it  necessitated  a  constant  pressure 
)n  the  pedal  while  driving — a  very  fatiguing  process. 

Gradual  Clutch  Release.  The  Dorris  clutch,  made  by  the  Dorris 
Motor  Car  Company,  St.  Louis,  Missouri,  Fig.  259,  is  a  new  arrange- 
ment of  the  clutch  pedal, 
and  its  operation  is  such 
that  the  clutch  is -released 
or  thrown  out  with  very 
light  pressure  on  the 
pedal.  Pressure  on  the 
petlal  A  is  transmitted 
by  the  shorter  lever  arm 
B,  thus  greatly  increas- 
ing the   leverage.     This 

pressure  is  transmitted  to 

lever  C  and  through  it  to 

lever  D,  these  two  being 

hung  on  the  frame  cross 

member  £.  As  C  is  much 

longer  than  D,  there  is 

another  multiplying  ac- 
I  tioQ  here.  This  does  not 
!  net  directly  upon  the 
:    clutch  but  upon  the  upper 

end  of  the  clutch  shifter 

'',  which  is  attached  to  the  clutch  at  G  and  pivoted  at  its  lower 

end  // — here  again  in  a  multiplying  action.     The  net  result  of  these 

three  multiplications  is  a  combination  which  will  release  the  -strongest 

and  stiffest  clutch  with  a  very  alight  pressure  of  the  foot. 

Clutch  Pedals.     It  has  been  the  general  practice  in  the  past  t^a 

have  the  clutch  pedals  separate  and  distinct,  wVtK  t.\ve  aeT\\!ce-\««Js.^ 


Fi(.  2W,     MulCiplyins  l^vpr  oF  Dorria  Clutcl 
Make  PhUI  Preraure  Light 
Canrlnu  «/  Dorrit  Motor  Car  Cimpanv,  SI. 


GASOLINE  AUTOMOBILES 


pedal  on  a  concentric  shaft  occasiouaJIy.  Now,  h<iwever,  tiw  rapidly 
growing  practice  of  stmpliiioatioit  and  elimination,  combined  with  the 
wide  use  of  the  unit  imwer  plant,  is  eliminating  the  so-called  c\utth 
shaft  with  its  hearings  and  fastenings  to  the  frame,  to  the  clutch 
operating  yoke,  and  to  many  other  parts.  A«  the  Cadillac  illiistm- 
tion,  Fig.  254,  shows  and  aa  the  Buick  drawing.  Fig.  2fiO,  shows  even 
better,  all  these  shafts,  rods,  and  fastenings  can  be  eliminated  and  the 
pedals  and  levers  mounted  directly  on  or  in  the  power  unit.  In  the 
Buick  illustration,  the  foot  brake  has  a  simple  rod  connection  from 
the  ear  -1  on  the  |)edal  to  the  brake-operating  system,   while  the 


GASOLINE  AUTOMOBILES  369 

springs  must  he  cared  for.  Generally,  these  two  cases  are  cared  for 
by  a  pair  of  grease  cups,  which  are  visible  in  Figs.  247  and  249. 
The  operating  rods  are  lubricated  usually  by  means  of  small  oil  holes, 
either  drilled  directly  into  the  part  or  covered  with  a  small  oil  cup. 
In  those  cases  in  which  the  clutch  runs  in  oil,  it  will  be  noted  that  a 
filling  plug  is  provided,  by  means  of  which  additional  lubricant  can 
be  poured  into  the  casing,  Fig.  256. 

Clutch-bearing  lubrication  is  highly  important,  particularly  with 
clutches  like  the  cone  which  must  be  kept  free  from  lubricant  and  the 
drv  disc  in  which  lubricant  is  not  used.  Where  the  clutch  itself 
runs  in  oil,  it  is  a  simple  matter  to  lubricate  the  bearings,  but  in 
the  other  cases,  oil  or  grease  must  be  provided  from  one  of  three 
places:  from  a  prolongation  of  the  engine  oiling  system,  as  shown  in 
Figs.  246  and  251;  from  the  outside — generally  by  means  of  grease 
cups — as  just  discussed;  or  from  the  transmission  end.  The  last 
form  is  used  only  in  unit  power  plants;  combinations  of  clutch  and 
transmission,  as  shown  in  Fig.  253;  and  in  cases.  Fig.  256,  where 
the  construction  allows  a  grease  or  an  oil  cup  attachment  at  the 
transmission  end,  the  transmission  itself  being  some  distance  away. 

Clutch  Bearings.  The  need  for  bearings  in  a  clutch  depends 
somewhat  upon  its  nature  and  location,  but  regardless  of  these  a 
thrust  bearing  is  needed  for  the  clutch  spring.  To  explain  this 
briefly,  it  is  known  that  action  and  reaction  are  equal,  and  opposite 
in  direction.  For  this  reason,  when  a  clutch  spring  presses  the  discs 
or  parts  together  with  a  force  of,  say,  100  pounds,  there  is  exerted 
in  the  opposite  direction  this  same  force  of  100  pounds.  In  order  to 
have  something  for  this  to  work  against,  a  bearing  is  used,  and  since 
it  takes  up  this  spring  thrust,  it  is  called  a  thrust  bearing.  Not  all 
bearings  are  fitted  to  take  thrust,  as  the  majority  are  designed  for 
radial  loads  only.    For  this  reason  a  special  design  is  needed. 

When  the  clutch  is  incorporated  in  the  fl^^heel,  two  additional 
bearings  —  one  for  the  end  of  the  crankshaft  and  another  for  the 
transmission  or  driven  shaft — are  generally  needed.  The  bearings 
will  be  noted  in  Figs.  246,  248,  and  249,  although  the  transmission- 
shaft  bearing  does  not  have  the  clutch  combined  with  the  engine  but 
rather  with  the  transmission.  In  the  majority  of  cases,  it  will  be 
found  that  a  means  of  fastening  the  end  of  one  shaft  has  been  worked 
out  so  as  to  eliminate  one  bearing.    This  accounts  for  the  lat^ 


370  GASOLINE  AITIOMOBILES 

number  which  show  but  two — tlie  thrust  and  one  other.  In  looking 
back  over  the  clutches,  it  will  be  noticed  also  that  nesriy  all  the  bear- 
ings are  of  the  plain  ball  fonn.  Tlis  is  due  in  large  part  to  the  bet 
that  the  plain  ball  bearings  take  tqi  the  least  room  for  the  toad  carried, 
both  in  diameter  and  width — a  coattibuting  reason  being  the  fact 
that  in  many  cases  one  of  the  shafts  at  parts  can  be  formed  to  take 
the  place  of  either  the  inner  or  outer  ball  race. 

dutch  Adjustment.  Adjusting  a  clutdi,  as  a  rule,  is  not  a 
difficult  task  as  there  are  but  two  possible  sources  of  adjustment — the 
throw  or  movement  of  the  operating  pedal  or  lever  and  the  tmsion 
of  the  spring.  ■  An  adjustment  is  generally  provided  for  each.  When 
the  fullest  possible  throw  of  the  pedal  does  not  disengage  the  dutch, 
an  adjustment  is  required  to  give  a  greater  throw.  If  the  throw  b 
correct,  but  the  clutch  takes  hold  too  quickly  and  vig(»oualy,  the 
spring  pressure  can  be  lessened  somewhat  to  soften  down  this  actlCH). 
On  the  other  hand,  when  dropped  in  quickly,  if  it  takes  hcdd  sk>iriy, 
more  spring  i)ressure  is  needed,  and  it  should  be  ti^tened. 

Clutch  Accessibility.  Clutches  are  made  accesuble  in  two  ways: 
by  their  location  on  the  car  and  by  the  relative  ease  with  whidi  they 
can  be  renio\e<l.    Accessibility  as  to  location  is  less  in  the  various 


GASOLINE  AUTOMOBILES 


371 


oil  or  grease  on  it.  In  that  case  it  is  desirable  to  roughen  the  surface. 
This  may  be  done  by  taking  the  clutch  out,  cleaning  the  surface  with 
kerosene  and  gasoline,  and  then  roughing-up  the  surface  with  a  file 
or  other  similar  tool. 

In  case  it  is  not  desired  to  take  the  clutch  out,  or  when  it  is  very 
inaccessible,  the  clutch  surface  may  be  roughened  bv  fastening  the 
clutch  pedal  in  its  extreme  out  position  nith  some  kmd  of  a  stick 
cord,  or  wire,  and  then  roughing  the  surface  as  far  in  as  it  can  be 
reached,  with  the  end  of  a  small  saw,  preferably  of  the  ke\  hole  t\  pe 
as  shown  in  Fig.  261.  Before  starting  this  repair  it  is  nell  to  soak 
the  leather  with  neat's-foot  oil.     This  softens  tlie  leather  and  makes 


SAW 


FLYWHECL 


the  roughening  task  lighter. 

Many  drivers  make  the  mis- 
take of  driving  with  the  foot 
constantly  on  the  clutch  pedal. 
This  wears  the  leather  surface 
and  helps  it  to  glaze  quickly. 
The  constant  rubbing  from  fre- 
quent slipping  makes  the  leather 
hard  and  dr>'. 

When  a  metal-to-metal  oiled 
clutch  slips,  the  trouble  usually  is 
[n  the  clutch  spring,  which  is  too 
weak  to  hold  the  plates  together.    To  remedv  shpping  with  this 
type,  it  is  necessary  to  tighten  up  the  clutch  spnng  adjustment 

Clutch  troubles  are  not  always  so  obvious  In  one  instance 
the  clutch  slipped  on  a  new  car.  In  the  shop  the  clutch  spider 
seemed  perfect  and  properly  adjusted,  also  the  spring  but  to  make 
sure,  a  new  clutch  was  put  in.  Still  the  clutch  slipped  To  test  it 
out  still  farther,  the  linkage  was  disconnected  right  at  the  clutch 
and  then  it  held  perfectly,  showing  that  the  trouble  was  m  the  link- 
age. On  examination  one  bushing  was  found  to  be  such  a  tight  fit 
that  it  would  not  allow  the  pedal  to  move  freely  enough  to  release  the 
clutch  fully.  When  this  was  relieved  a  little,  the  clutch  acted  all  right. 

R^lacing  Clutch  Leathers.  Clutches  offer  many  chances  for 
trouble.  The  most  frequent  causes  are  the  wear  of  leather  facings 
with  the  attendant  loss  of  power,  and  weak  springs.  Weak  springs 
may  be  cured  by  screwing  up  on  the  adjusting  nut  or  bolt  pTo^vi>e\. 


m 


GASOLINE  AUTOMOBILES 


Slippery  leather  may  also  be  corrt'ctccl  by  washing;  first  with  goM- 
line  ami  then  with  wuter,  finally  rou^huig  the  surface  with  a  aiarse 
r»3p  and  replacing  only  after  tlie  leatlier  is  thorouglily  eleaa.  Dry 
leather  is  fixed  by  soaking  in  water  or  neatVfoot  oil.  !t  should  he 
replace<l  while  still  moist,  aad  copious  lubrication  will  keep  it  soft. 
The  greatest  problem  in  replacing  a  worn,  charred,  or  otherwise 
defective  leather  lies  in  getting  the  right  layout  for  the  form  of  the 
new  leather  the  first  time.     It  must  be  remembered  that  the  surface 


is  a  portion  of  ti 


and,  therefore,  its  development  is  not  eas>'. 
It  is  attacked  iu  this  man- 
ner:   Prepare   the  cone  by 
removing    the   old   leather 
\  and  all  rivets,  cleaning  out 

\  the  rivet  holes,  and  pmvid- 

\  ing  new  rivets.  Measure  the 

•  rone,  taking  the  diameters 

',  at  both  the  large  and  small 

t  ends  and   also    Uie  width. 

■  '--._/■ Take  a  large  sliect  of  papei 

.*'  .'  and  lay  otT  upon  it  a  figure 


GASOLINE  AUTOMOBILES 


373 


IIIBCKJDAH  may  then  be  cut  out  and  used  as  a  pattern  from 
which  to  cut  out  clutch  leathers.  If  the  distances  AH  and  DJ  be 
made  approximately  equal  to  or  slightly  more  than  ^Z>,  the  pattern 
will  a  little  more  than  encircle  the  cone  clutch. . 

After  the  leather  has  been  cut  out,  it  should  be  prepared  by 
soaking  in  water  or  oil,  according  as  its  surface  is  fairly  soft  or  rather 
harsh.  In  either  case,  it  must  be  well  soaked,  so  as  to  stretch  easily. 
In  putting  it  on  the  cone,  one  end  is  cut  to  a  diagonal,  laid  down  on 
the  cone,  and  riveted  in  place.  Next,  the  leather  is  drawn  down 
tightly  past  the  next  pair  of  rivet  holes,  which  are  then  driven  into 
place.  This  is  continued  until  the  strip  is  secured.  The  leather  is 
now  wetted  again,  for,  if  allowed  to  dry  off  immediately,  the  shrinking 
action  will  break  it  out  at  most  of  the  rivet  holes  and  render  it  use- 
less. By  drying  it  out  gradually,  a  taut  condi- 
tion may  be  arrived  at  without  this  danger. 

Handling  Clutch  Springs.   Clutch  springs, 
like  the  valve  springs  mentioned  previously, 
are  mean  to  handle  and  compress.    The  best 
way  is  to  compress  and  hold  them  compressed    ^^  -,  ^   j 
until  needed.    For  this  purpose,  a  rig  similar    ^     -■*  ' 
to  that  described  for  valve  springs  should  be 
made  but  of  stiffer  stronger  stock.     A  very 
good  one  can  be  made  from  two  round  plates, 
one  small,  and  the  other  of  larger  diameter  with 
a  pair  of  L-shaped  bolts  through   it.     The 
spring  is  placed  between  the  two,  with   the 
ends  of  the  L's  looped  over  the  smaller  plate,  and  then,  by  tight- 
ening the  nuts  on  the  bolts,  the  spring   is   gradually  compressed. 

An  excellent  device  for  holding  clutch  springs  consists  of  a 
simple  pair  of  metal  clamps  which  are  juinefl  together  by  three  or 
more  short  metal  bars,  as  Fig.  263  shows.  If  one  particular  clutch 
spring  is  handled  continuously,  the  length  can  be  made  to  fit  this 
best,  otherwise  it  will  have  to  be  made  of  any  convenient  length. 
The  inside  diameter  of  the  clamps  when  fully  open  is  greater  than 
the  outside  diameter  of  the  spring.  The  clamp  is  set  in  a  vise  or  on 
a  drill  press  and  the  spring  set  inside  of  it.  Then  the  spring  is  com- 
pressed by  working  the  vise  handle  or  by  lowering  the  drill-press 
spUtdie.     When  compressed  down  to  the  length  used  in  the  car,  the 


374 


GASOLINE  AUTOMOBILES 


ends  of  the  clamp  are  tightened  and  the  spring  is  lield  by  fricticm. 

Then  tlie  spring  can  be  Imndled  readily,  using  one  of  the  metal  bars 

es  a  handle.    It  is  put  into  place,  and  then  the  retaining  screws  cbo 

be  loosened  and  the  clamp  removed. 

Fierce  Clutch.    A  fierce  clutch  is  one   that   does    not    takv 

hold  gradually  but  grabs  the  moment  the  clutcli  pedal  is  released. 

In  a  metal-disc  clutch,  tliis  is  caused  by  mughenwl  plate  stirTaccH 

and  insufficient  lubricant,  so  that,  instead  of  the  plates  twisdnf; 

gradually  across  each  other  as  llie  lubricant  is  sqiieexed  nut  from 

between  them,  they  catch  at  once  and  tlie  car  atarta  with  it  jerk. 

On  a  cone  clutch,  this  fierceness  is  produced  by  too  stronK  n  spring, 
too  large  a  clutching  sur- 
face in  combination  mitb  a 
very  strong  spring,  or  a  liaitl 
or  [)urned  clutch  surface  or 
botb. 

Ford  Clutch  Troubles. 
There  are  now  so  many 
Fortis  in  use  that  the  avcr^ 


GASOUXE  An»MOBILES 


cmter  bolt,  vfaich  b  ^ii^tly  pvinnd  and  ptHrnbty  hudeDed  <,« 
the  end,  is  screwed  down  io  »5  to  o^me  into  ixxitwrt  with  the  end 
of  the  dutch  shaft.  After  ti^tenin^  tbe  center  hoh.  the  T-hnMl 
bolts  are  righteoed  until  they  pull  tbe  dnun  off  the  shaft. 

Chitch  Spimiag.  A  miuble  which  i$  both<n^iine  but  Dot 
dangerous  is  dutch  spinning.  This  is  the  name  applied  to  the 
action  of  the  male  dutch  member  when  it  c\>ntinue$  to  nutate,  or 
spin,  after  the  dutcb  5|»in$  pre:5i>ure  has  been  teleased.  With  tbe 
male  member  connected  up  to  the  principal  transmission  shaft  ami 
gear,  as  is  often  the  case,  these  members  continue  to  rvute  with  it. 
This  gives  trouble  mainly  in  gear  shifting,  for  the  member  which  b 
out  of  engagement  is  considereil  to  be  at  rest  or  rapidly  appitvkching 
that  condition.  VNTien  at  rest,  it  is  an  easy  matter  to  mesh  anothn* 
gear  nith  this  one:  but  when  this  one  is  rotating  or  spinning,  it  is 
not  so  easy,  particularly  for  the  novice. 


■ifm 


:^i 


fif.  m.     Simplr  Devin  lor  toHrtintt  Corki  ia  ClutrbM 

Clutch  spinning  may  l>e  caused  {U  by  a  defect  in  the  design. 
in  which  case  little  can  be  done  with  it;  (2)  by  a  defect  in  construi'- 
tion,  as  in  balancing,  for  instance,  which  can  l>e  <i)n^H'ted;  t)r  (li) 
it  may  be  due  to  external  causes,  as,  for  instance,  in  a  bearing  which 
has  seized,  owing  to  a  lack  of  lubricant,  etc. 

In  an}'  case,  the  best  and  quickest  remedy  is  a  form  of  clutch 
spinning  brake.  This  may  consist  simply  of  a  ftmall  pait  of  leHtlier 
or  of  metal  covered  with  leather  so  located  on  the  frame  members 
that  the  male  drum  touches  against  it  when  fully  released.  Or  it 
may  be  something  more  elaborate  as  to  size  or  construction  or  both. 
On  many  modern  cars,  in  fact  on  practically  all  good  car.-!,  .some  fonu 
of  clutch  spinning  brake  is  fitted.  Thus,  in  the  llelt^Shaw  design. 
Fig.  256,  metal  cones  of  small  diameter  are  provided,  while  Fig.  JiVi 
shows  flat  concentric  discs  of  its  Locomobile  clutch. 

Cork  Inserts.  When  cork  inserts  are  used  in  a  clutch,  the 
insertion  of  new  corks  is  not  an  easy  job.  A  cork  is  a  difficult.  asA 
unhandy  thiiyr  to  work  with,  and  above  all  to  ho\d  stm^jA  *^'^  ^^^^ 


GASOLINE  AUTOMOBILES 

while  apphing  longitiKlmal  force  to  it.  By  making  up  a  special 
tool  with  a  tubular  nicuiber  having  an  innej  taper,  into  which  the 
corks  are  forced  by  means  of  a  special  plunger  which  forms  the  other 
part  of  the  too!,  this  is  simplified  considerably.  Tliis  tool  is  shown 
in  Fig.  2(i5,  with  suoh  dimensions  as  would  lie  needed  for  a  J-inch 
cork.  It  is  advisable  to  make  the  small  end  of  the  tube  {  inch  smaller 
than  the  cork,  as  this  amount  provides  the  proper  compression, 
After  being  soaked  in  water  for  10  or  15  minutes,  the  cork  is  dropped 
into  the  large  end  of  the  tube,  and,  with  the  small  end  in  place 
against  the  cork  opening  in  the 
clutch,  a  single  stroke  of  the  plunger 
will  force  the  cork  through  the  tm»l. 
incidentally  compressing  it  into  the 
hole  in  the  ciutoh.  With  a  few 
handlings  any  clever  mechanic  can 
soon  become  expert  in  the  use  of 
this  tool, 

A  more  elaborate  device,  but 
one  which  works  more  quickly  where 
there  iM  a  great  deal  of  this  work,  is* 


GASOLINE  AUTOMOBILES 


377 


In  Fig.  267,  several  other  common  clutch  troubles  and  their 
remedies  are  suggested ;  the  parts  shown  in  the  illustration,  however, 
are  in  excellent  condition,  in  fact,  new. 

When  the  right  kind  of  clutch  discs  for  a  multiple^isc  form  are 
not  on  hand,  new  discs  can  be  cut  from  leather  to  answer  the  purpose 
by  means  of  the  gasket  cutter,  shown  in  Fig.  268.  This  cutter  con- 
sists of  a  pair  of  steel  L-shaped  arms,  preferably  forged,  with  points 
sharpened  enough  to  cut  the  leather  of  the  gasket  material.  The 
clamp  has  a  point  for  the  center  of  the  circle  on  its  under  side,  while 


"Rjtonnewlim-n^ 


tor  -••J^ar  m 


uiBversol 


joint  hoshir^ 
\feilaoe  all  Trussing 


,51tKi>31  W  sHp  joint 


Surfaced  @'  well  oiled. 
Fig.  367.  Clutch  l^ouUes  lUuMntrd 
the  actual  clamping  is  done  by  the  bolt  .or  screw  with  wing  head. 
To  use  for  clutch  discs,  set  the  inner,  or  shorter,  member  to  the  radius 
of  the  inside  of  the  outer  discs  and  the  outer,  or  longer,  arm  to  the 
radius  of  the  outside  of  the  inner  discs.  By  pressing  down  hard  on 
the  arms  and  rotating  them  at  the  same  time,  an  annular  ring  will 
be  cut  out  which  will  fit  exactly.  One  hand  should  be  held  on  or 
near  the  center,  while  the  other  hand  supplies  the  pressure  and 
rotating  motion  on  the  cutting  ends.  It  should  not  be  expected  that 
the  points  will  cut  through  in  one  revolution;  on  the  conltM'y  A'wfc 
first  tirae  around  will  just  marJc  out  the  section  and  \t.  ViW  weeA  Ixcta. 


378  GASOLINE  AUTOMOBILES 

(i  to  10  revolutions,  with  heavy  pressure,  to  cut  a  leather  disc.    In 
time,  the  workman  will  be(.*ome  sicillecl  in  the  use  of  this  cutter  and 


Pig.  2118.    Mplhod  of  Cullinii  Fuing  for  DiiF  CIuii-Iih  it  an  Eii.crgvnrr 

have  a  knowledge  of  its  hmtts,  as  well  as  of  tlie  method  of  keeping  it 
in  good  cutting  order. 

Adjusting  Clutch  Pedals.  Some  cars  are  mode  with  adjustable 
clutch  pedals  so  the  long-  or  short-legged  driver  can  set  the  length  of 
these  to  suit,  but  when  no  adjustment  is  provided  and  it  is  desired 
to  change  the  length,  some  figuring  must  be  done.  To  shorten  a 
non-ad j nestable  pedal,  the  beat  way  ts  to  take  it  out  of  the  car  and 


GASOLINE  AUTOMOBILES  379 

to^'ether  at  the  other  end.     Thest*  are  bolteil  in  at  J,  where  the  pad 
V    was  formerly,  and  the  pad  moved  out  to  the  new  end  at  B.     In  some 
such  cases,  where  the  sides  of  the  pedal  shank  offer  no  groove  to  help 
hold  the  steel  strips,  it  is  necessary  to  put  another  bolt  through  them, 
as  at  C,  to  prevent  the  whole  addition  swinging  about  ^  as  a  cente^. 
Qutch  Troubles  Outside  of  Clutch.    Frequently,  there  is  trouble 
in  the  clutch  when  the  basic  reason  for  it  is  outside  of  the  clutch 
entirely.    Thus,  failure  of  a  clutch  to  engage  or  disengage  properly 
is  often  the  fault  of  ^e  connecting  rods  and  levers;  wear  in  the  clutch 
collar  or  in  other  parts;  or  the  emergency-brake  interlock  may  have 
been  fitted  so  close  that  as  soon  as  the  rods  are  shortened  once  or 
twice  to  compensate  for  wear,  it  stands  in  such  a  position  as  to  throw 
the  clutch  out  slightly  although  the  latter  appears  to  be  fully  engaged. 
Another  clutch  trouble  outside  of  the  clutch  is  apparent  slipping 
at  comers,  especially  at  turns  on  grades.    On  a  turn — the  road  being 
cambered — the  frame  is  distorted,  especially  with  the  combination  of 
curve  and  grade.    This  may  be  sufficient  to  throw  the  clutch  and 
driving  shaft  out  of  alignment  just  enough  so  the  clutch  face  will  not 
make  full  contact.    This  is  most  noticeable  on  cars  with  a  single 
universal  joint,  in  which  case  the  distortion  of  the  frame  has  more 
effect  on  the  driving  shaft.    Similarly,  a  car  with  an  unusually  light 
or  flexible  frame  will  show  this  trouble  very  often,  as  the  combination 
of  curve  and  grade  is  too  much  for  the  light  frame. 

Summary  of  Clutch  Troubles 

Throwing  in  Clutch.  Do  not  throw  clutch  in  suddenly  and  cause 
rear  wheels  to  spin.  Such  action  is  destructive  to  tires  and  throws 
great  stress  on  the  entire  mechanism  of  the  car. 

Lubricating  Multiple-Disc  Clutches.  These  are  best  lubricated 
by  injecting  oil  into  the  opening  for  that  purpose  by  means  of  an  oil 
gun.    A  very  light  lubricating  oil  should  be  used. 

Multiple-Disc  Qutches  Failing  to  Hold.  Inject  three  or  four 
gunfuls  of  kerosene  into  the  clutch  housing  and  run  the  engine  a 
little,  thereby  washing  out  the  plates  of  the  clutch.  This  will  cut 
the  giun  caused  by  the  oil.  If,  after  this  treatment,  the  clutch 
squeaks  or  takes  hold  too  suddenly,  lubricating  oil  may  be  added. 

Loss  of  Power.  This  is  noticeable  in  changing  from  intermediate 
to  high  gear,  in  dimhmg  bills,  or  in  running  througVi  mwdA^  ox  ^^^sA^ 


3S0  GASOLINE  AUTOMOBILES 

roads.  The  trouble  is  often  the  result  of  the  clutcli  slipping.  The 
remedy  is  to  clean  the  clutch  with  gatioHiic  and,  if  the  clutch  is  leather- 
faced,  to  apply  castor  oil  after  cleaning.  Castor  oil  should  never  be 
used  on  the  multiple-disc  clutch- 
Failure  of  Clutch  to  Take  Hold.  This  may  be  owing  to  a  broken 
or  weakened  clutch  spring,  the  dutch  leather  may  be  dama^'ni. 
clutch  shaft  may  be  out  of  hne  or  bent,  leather  may  be  gummed, 
or  bearing  may  be  seizing. 

TRANSMISSION  GROUP 

Primarily,  the  clutch  is  used  to  allow  the  use  of  change-speed 
gearing;  or,  stated  in  the  reverse  way,  the  form  of  the  transmission 
determines  whether  a  clutch  must  be  UHcd  or  not,  there  being  cases  in 
which  it  is  not  userl.  Thus,  where  the  frictional  form  of  transmission 
is  used,  no  clutch  is  necessary;  the  frictional  discs  act  as  a  clutch 
and  render  another  one  superfluous.  So,  too.  with  the  form  of  tra»3> 
mission  known  as  the  iitanetari/  gear,  no  master  clutch  is  needed. 

On  the  other  hand,  the  reverse  of  this  docs  not  always  hold.  Anjt  I 
form  of  clutch  maj-  be  used  witli  the  various  other  forms  of  tranamif- J 
sion,  as  the  sliding  gear;  in  fact,  in  actual  practice  every  known  kiotl  1 
of  a  clutch  will  be  found  coupled  with  the  sHdinE-gear  transmissioB.  I 


I 


GASOLINE  AUTOMOBILES  381 

ness  has  brought  with  it  a  stiffness  which  has  rendered  less  repairs 
and  adjustments  necessary,  despite  lighter  weight.  The  smaller  sizes 
have  brought  about  the  simplification  and  lighter  weight,  and  in 
turn  have  been  produced  in  answer  to  the  popular  demand  for  lighter 
weight  cars.  In  part,  simplification  has  been-  produced  by  unit 
power  plants,  now  so  popular. 

SLIDING  GEARS 

General  Method  of  Operation.  Of  the  different  types  of  sliding 
gears,  the  first  two  subdivisions  are  not  very  closely  marked,  but 
blend  somewhat  into  one  another.  The  only  real  difference  between 
them  is  the  method  of  operation,  the  names  serving  to  indicate  the 
distinctive  characteristics.  Thus,  in  a  selective  gearset,  it  is  possible 
to  "select**  any  one  speed  and  change  directly  into  it  without  going 
through  any  other.  So,  too,  in  the  progressive  form  of  transmission, 
the  act  of  changing  gears  is  a  "progressive'*  one,  from  the  lowest  up 
to  the  highest,  and  vice  versa. 

Selective  Type.  With  the  selective  method  of  changing  gears, 
it  is  possible  to  make  the  change  at  once  from  any  particular  gear 
to  the  desired  gear  without  passing  through  any  other.  Of  course, 
the  car  will  not  start  on  the  high  gear  any  more  than  in  the  other 
case,  but  shifting  into  low  for  starting  purposes  is  but  a  single  action, 
accomplished  quicker  than  it  can  be  told.  So,  too,  when  the  car  has 
been  started,  it  can  be  allowed  to  attain  quite  a  fair  speed  and  the 
change  to  high  made  at  once  without  going  through  the  intermediate 
gears. 

Progressive  Type.  Progressive  gears,  which  are  now  little  used, 
op)erate  progressively:  from  first,  or  low,  to  second  and  from  second 
to  third,  or  high;  in  slowing  down,  from  third  to  second  to  first 
and  in  this  way  only.  This  leads  to  a  number  of  troublesome 
occurrences;  thus,  in  stopping,  it  is  necessary  to  gear  down  through 
all  the  higher  speeds  into  low.  If  this  is  not  done,  when  it  is  next 
desired  to  start  the  car,  it  will  be  necessary  to  start  the  engine,  throw 
in  the  clutch,  drop  from  the  gear  in  mesh  to  the  next  lower,  from  that 
to  the  next,  and  so  on  down  to  low,  throwing  the  clutch  out  and  in 
for  each  change  of  speed.  When  first  is  reached,  the  car  may  be 
started.  After  starting,  it  is  then  necessary,  in  order  to  obtain  any 
measurable  speed  with  the  car,  to  change  back  up  the  Ust,  from  low 


382  GASOLINE  AUTOMOBILES 

to  second,  from  second  to  third,  and  bo  forth.  In  this  way  the  pixv- 
gressive  gear  is  di^dvantAfceous,  sinre  its  use  means  much  gear 
shifting;  but,  on  the  other  hand,  the  shifting  is  very  easy  for  the 
novice  to  learn,  as  it  is  a  continuous  process,  all  in  one  diretrtioii. 
Modern  Selective  Types.  To  present  some  modern  selective 
types  of  gear  boxes  ami  point  out  their  various  differences.  u<Ivan* 
tagcs,  and  ilisad vantages,  refer  to  Vig.  270.  This  tjpe  shows  the 
three-speed  selective  gear  used  on  llie  Cadillac  cars,  which  is  but 
slightly  modified  from  the  t>-pe  which  has  been  used  by  this  concern 
(or  three  years.    This  change  should  be  noted,  howe\'ct:  the  lay- 


GASOLINE  AUTOMOBILES  383 

and  with  another  on  the  third  shaft  for  reverse.  The  reverse  gear 
is  at  all  times  in  mesh  with  the  fourth  layshaft  gear,  so  that  on 
reverse  the  drive  is  through  five  gears  instead  of  four.  On  high  gear 
the  drive  is  through  the  dogs,  the  layshaft  being  driven,  of  course, 
but  silently,  as  it  transmits  no  power. 

Four-Speed  Type  wUk  Direct  Drive  on  High.  One  of  the  tend- 
encies of  recent  years  has  been  the  gradual  change  toward  more 
speeds,  as  shown  by  the  increasing  use  of  four-speed  gear  boxes. 


Other  indications  of  this  change  have  been  the  two-speed  axle,  which 
gftve  double  the  number  of  gear-box  speeds,  with  the  ordinary  three- 
speed  and  reverse  transmission;  and  the  electric  transmission,  which 
affords  seven  forward  and  two  reverse  speeds. 

Following  this  increase  of  speeds,  the  multi-cylinder  motors  and 
downward  price  revisions  of  the  early  part  of  1916  brought  about  a 
ocHnbination  which  almost  eliminated  the  four-speed  gear  box  or  at 
least  removed  it  from  all  but  the  most  expensive  ol  c&x%  uA  Vtcjov 


■iM 


GASOLINE  AUTOMOBILES 


many  of  those.  It  13  claimed  that  the  eight-  aiu]  twelve-cylinder 
motors  have  so  nuich  power  and  flexibility  that  a  fourth  speed  is 
rendered  un^eces5a^^■.  The  four-speed  gear  box  is  more  expensive 
than  the  tliree-speed  box.  and  the  lowered  prices  of  cars  have  been 
instrumental  in  preventing  \U  continued  use.  At  the  same  time, 
there  was  considerable  lightening  of  weight  all  over  the  chassis,  and 
the  four-speed  gear  box  had  to  go  out  of  all  but  the  biggest  cars  on 
account  of  its  greater  weight. 

Fig.  271  is  a  sectional  plan  of  one  of  the  few  four-s|>ei*d  geur 
boxes  left.  In  this  drawing  it  will  be  noted  that  the  two-gear  shafts, 
as  well  as  the  operating  shafts,  lie  in  the  same  horizontal  plane.  Tlie 
halftone  rcprtKluction  of  the  photograph  of  this  drawing.  Fig.  272, 


GASOLINE  AUTOMOBILES  385 

Four^Speed  Type  with  Direct  Drive  on  Third.  In  all  the  trans- 
missions shown  and  described  thus  far,  the  direct  drive  has  been 
the  highest  speed.  By  referring  back  to  Fig.  253,  which  show  the 
Winton  four-speed  gear  box,  as  well  as  the  clutch,  a  point  of  difference 
will  be  seen.  This  has  the  direct  drive  on  third  speed,  fourth  being  a 
geared-up  speed  for  use  only  in  emergencies,  when  the  very  highest 
rate  of  travel  is  required,  and  when  a  little  noise  more  or  less  would 
make  no  difference.  This  arrangement  of  the  direct  drive  and  silent 
speed  has  long  been  a  debated  point,  some  designers  favoring  the 
direct-drive  type  with  an  over-geared  speed  for  occasional  use,  while 
the  opponents  of  this  method  say  that  this  construction  practically 
reduces  the  transmission  to  a  three-speed  basis,  the  fourth  being  so 
seldom  used  that  it  is  practically  negligible.  They  say,  also,  that  the 
modern  motor  can  attain  a  high  enough  speed,  on  the  one  hand,  and  is 
flexible  enough,  on  the  other,  to  permit  its  being  used  with  the  high- 
gear  direct  drive  upon  almost  all  occasions. 

Transmission  Location.  There  are  but  four  recognized  positions 
for  the  transmission  in  the  modern  car.  These  are:  (1)  unit  with  the 
engine  (unit  power  plant),  (2)  amidships  in  unit  with  clutch  or  alone 
in  a  forward  position,  (3)  amidships  in  unit  with  forward  end  driving 
shaft  or  in  a  rear  position,  and  (4)  at  the  rear  in  unit  with  rear  axle. 
Unit  vnth  Engine,  The  unit  with  the  engine  type  is  illustrated  in 
an  excellent  manner  in  Fig.  273,  which  shows  the  eight-cylinder 
Northway  motor,  cone  clutch,  and  three-speed  transmission.  Some 
idea  of  the  compactness  of  this  outfit,  which  is  shown  exactly  as  used  on 
the  Oakland  car,  can  be  gained  from  comparison  with  cylinder  bore 
and  crankshaft  size,  the  motor  being  3i  by  4^  inches.  The  notice- 
able features  of  the  transmission,  aside  from  its  compactness,  are  the 
use  of  double  row  ball  bearings  on  the  splined  main  shaft,  with  a 
Hyatt  roller  form  for  the  spigot  bearing  (free  end  of  main  shaft)  and 
very  long  plain  bronze  bushing  for  the  countershaft  unit,  the  latter 
being  made  as  a  single  piece  rotating  on  a  single  bearing  around  a 
straight  fixed  shaft.  The  countershaft,  or  layshaft,  as  it  is  some- 
times called,  is  placed  below  the  main  shaft. 

Another  example  of  the  unit  with  engine  type  is  seen  in  the 
Grant-Lee  three-speed  gear  box.  Fig.  274,  as  utilized  in  the  Hackett 
car.  This  is  unusually  small  and  compact,  as  will  be  noted  by  cttvsk- 
paring  the  size  of  the  unit  with  the  operating  levers  and  peA«\.   \s\v!^fc 


OASOLINE  AUTOMOBILES 


If 


GASOLINE  AUTOMOBILES 


387 


the  clutch  is  not  shown,  its  housing  is,  also  the  flange  which  attaches 
it  to  the  flywheel  housing  to  complete  the  power  unit.  A  third 
example  of  the  engine-unit  power  group  is  shown  in  Fig.  275,  which 
shows  the  flywheel,  clutch,  and  transinission  of  the  Peerless  eight. 
This  unit  transmits  many  times  the  power  of  the  Hackett  unit  and 
is  therefore  much  iaiger.  In  this  unit  the  bearing  arrangement  is 
rather  unusual,  as  roller 
bearings  of  the  taper  form 
are  used  on  the  main  shaft, 
a  straight  roller  for  the 
spigot  bearing,  and  plain 
ball  bearings  for  the  lay- 
shaft.  The  shortness  and 
large  diameter  of  the 
shafts  should  be  noted. 

Additional  transmis- 
sions in  a  unit  with  clutch 
and  motor  will  be  seen 
under  Clutches,  in  Figs. 
251 ,  252,  and  254. 

Amidships  AUme  or 
irilh  Clvtck.  The  amid- 
ships unit  joined  with  the 
clutch,  shown  in  Fig.  253, 
represents  the  Winton 
transmission  and  clutch. 
This  is  not  a  common  con- 
struction on  pleasure  cars, 
although  it  is  used  on 
quite  a  number  of  trucks. 
On  the  amidships-clutch 

unit   type,   however,  the  _^ 

combinationisnotquiteso  J"*™.  Mtr^iiGn 

intimate  as  the  one  in  which  the  two  units  are  enclosed  ina  common  case. 

Amidships  Joined  with  Driving  Shaft.  The  amidships  unit 
joined  with  the  forward  end  of  the  driving  shaft  is  well  shown  by  the 
Locomobile,  Figa.  271  and  272.  The  universal  joint  *\lh.  tiic  Arwavfe- 
shaft  pivots  is  seen  Bt  the  left  side  of  both  theae  v\ewa,    \n.  '^^ 


388  GASOLINE  AUTOMOBILES 

construction,  wliicli  is  more'  widely  used  ihaii  the  other  omidship:^ 
arrangement,  tiiere  is  usually  a  frame  crus*-member  at  the  point  on 
which  the  rear  end  of  the  transmission  is  supported.  This  same 
arrangement  is  used  on  the  Steams-Knight  four-cjlinrler  chassis,  the 
transmission  of  which  is  shown  in  Fig.  276.  In  this  transmission 
the  stiffness  of  tlie  eniss-member  at  the  rear  end  of  tJie  transmission 
is  also  utilized  to  support  the  hrake  ciriim  of  the  frK)t-l)rake  system. 


GASOLINE  AUTOMOBILES  389 

Rear  Unit  with  Rear  Axle.  The  position  at  the  rear  axle  is 
not  as  widely  used  as  a  couple  of  years  ago,  hut  those  manufacturers 
using  it  have  large  outputs,  so  that  a  considerable  number  of  these 
fiars  are  in  use  and  considerably  more  are  being  added  each  year. 
One  of  these,  the  Studebaker,  is  shown  in  Fig.  277.  This  is  a  shadow 
<Irawing  of  the  rear  axle  and  transmission,  showing  the  upper,  or 
main,  shaft  of  the  transmission  in  full  and  the  layshaft  which  is  below 


it,  partially.  As  will  be  noted,  this  position  of  the  transmission 
calls  for  two  operating  rods,  each  the  full  length  from  the  operating 
levers  to  the  rear  axle.  The  rod  on  the  left  operates  the  reverse 
and  first  speeds  and  that  on  the  right  second  and  third,  or  high,  speeds. 
To  make  this  shifting  of  gears  and  connection  of  levers  with 
the  actual  position  of  the  gears  plain,  Fig.  278  is  also  shown.  In 
this  figure  the  gear-shifting  lever  is  placed  in.the  center  and  is  shown 
solid  in  the  neutral  position  and  lighter  in  the  other  four  '^osASon?.. 


GASOLINE  AUTOMOBILES 


Just  below  it,  the  traiismisHion  is  shown  with  the  position  of  the 
gears  for  neutral,  whilt?  in  the  four  corners,  forrespomling  to  Uie  four 
positions  of  the  lever,  tlic  [wsitions  trf  the  gears  when  the  lcv» 
is  in  each  one  of  the  positions  are  shown.  These  positions  indicutf 
that  there  is  a  driving  gear  and  two  sliding 
nieinl>er3  on  the  main  shaft  and  four  gears 
on  the  layahaft.  At  the  left  in  the  picture, 
the  gear  toward  the  rear  is  for  reverse  and 
another  gear  (not  shown)  is  needed  to  com- 
plete the  re\'ersal  of  motion.  When  the 
lever  is  swung  to  tlie  left  and  forward,  this 
group  is  completed  and  reverse  s|)eed 
results. 

When  the  lever  is  swung  to  the  left 
and   pullfd   backwards,  the  rtJir  sliding 


GASOLINE  AUTOMOBILES 


391 


nd  over  to  the  right^a  furtlier  movement  to  tlie  front  picks  up  the 
iruanl  slidinfr  gear  and  moves  it  back  into  mesh  with  the  third  gear 
n  the  la.\'shaft;  tliis  combination,  as  shown  in  the  upper  right-lmnd 
omer,  gives  second  speed.     When  the  lever  is  moved  back,  it  moves 


THIRD  SPEED 


Fi|,  ZTS.     Diagnnu  Showing  Working  uf  Sludebakcr  Tni 


he  gear  forward,  giving  high  speed  and  direct  drive,  as  shounfi  at  tlie 
>wer  right-hand  comer. 

Interlocking  Devices.  Nearly  all  transmissions  have  a  form  of 
top  lock  on  the  shifting  rods  in  tlie  transmission,  wliich  holds  the 
■ears  in  mesh  as  soon  as  they  have  been  moved  by  the  operator 
inti!  he  moves  them  again.  In  reality  this  arrangement  simply 
irevents  the  gears  from  jumping  out  of  mesh.  Generally,  the  most 
imple  arrangement  which  will  hold  the  gears  is  used.    In  tlie  ordinary 


392  GASOLINE  AUTOMOBILES 

form  this  arrangement  consists  of  hardened  steel  wedges  with  liglii 
springs  hack  of  tliem  and  deeji  grooves  in  the  shifting  rods  into  which 
these  wedges  fit. 

In  Figs.  271  and  272,  the  notches  in  the  shiftjiig  rods  (sn  he 
seen  plainly.  In  Fig.  275,  the  bolt  hewl  A  indicates  the  jocatinn 
of  one  of  the  shifting  locks.     In  Fig.  277,  .!  shows  the  notches  in 


(rim 


iJmn imil 


GASOLINE  AUTOMOBILES 


393 


)iiipany,  the  grooves  in  the  rods  being  deep  enough  to  accommodate 
is  form  in  a.neutral  position  so  that  the  rod  can  be  started.  But  the 
ide  hole  in  'the  central  housing  in  which  the  pin  is  moved  across  by 
e  motion  of  one  rod,  owing  to  the  shape  of  the  bottom  of  the  groove, 
events  the  other  rod  from  moving. 

Electrically  Operated  Qears.  In  substance,  the  electrically 
erated  transmission  has  all  the  hand  levers,  rods,  and  other  levers 
placed  by  a  series  of  push  buttons.  When  it  is  desired  to  change 
eeds,  even  before  the  actual  change  is  necessary,  the  driver  presses 
B  button  marked  for  the  speed  he  thinks  he  will  require.  Then, 
len  the  actual  need  becomes  apparent,  he  throws  out  the  clutch 
d  immediately  drops  it  back  again,  all  this  forming  but  a  single 
•ward  and  back  movement  of  the 
>t.  During  the  slight  interval  while 
e  clutch  is  out,  the  electrical  connec- 
>ns  shift  the  gears  automatically,  so 
at  when  the  clutch  is  let  back,  the 
ars  are  meshed  ready  to  drive. 

Principle  of  Action.  To  explain 
Is  action  briefly,  the  gears  are  moved 
means  of  solenoid  magnets,  which 
3  nothing  more  than  coils  of  wire, 
rough  which  an  electric  cifrrent  from 
onvenient  battery  is  allowed  to  pass, 
irough  the  center  of  each  one  of  these 
lis  passes  an  iron  bar.  When  a  cur- 
it  passes  through  the  coil,  it  is  cou- 
rted into  an  electromagnet  and  draws  the  iron  bar  inward.  As  the 
her  end  of  the  bar  is  connected  to  the  gear  to  be  shifted,  this  move- 
jnt  of  the  bar  shifts  the  gear.  Consequently,  when  the  button  is 
essed  so  that  current  flows  through  one  of  the  coils,  that  action 
ifts  the  gear  for  which  the  button  is  marked. 

By  referring  to  Fig.  280,  this  action  will  be  made  more  clear. 
16  diagram  shows  but  one  pair  of  gears  to  be  meshed,  and  the 
ttery,  push  button  S,  coil  D,  iron  bar  P,  and  clutch  connection 
are  all  shown  as  simply  as  possible.  When  button  S  is  pressed, 
rrent  through  the  coil  D  will  draw  the  bar  P  and  mesh  the 
ars  as  soon  as  the  clutch  has  been  thrown  out,  thereby  closing 


Fig.  280.     Sketch  Showing  How  a 

Solenoid  Moves  a  Gear  When 

Current  Flows 


GASOLINE  AUTOMOBILES 


the  circuit  nt  M.    Tlie  application  of  this  to  an  actual  transmission 
is  shown  nmro  in  iletail  in  Fig.  281,  which  shows  the  dutch  pedal 


C-H  Electric  Geu  Shift 

and  its  cDrnifction  to  the  six  solenoids  necessary  to  produce  four 
ffirwani  s|)cm!s,  imc  rcvirst' speed,  and  a  neutral  point. 

On  the  Mtcerinj;  wlieel,  Fig.  282,  the  control  group  of  six  buttons 
will  he  imtcd  on  the  sniiill  round  plate  at  the  center,  with  the  addition 
of  tlic  hnrri  liuttiin  in  the  center.  In  Fig.  283  is  another  arrangement. 
IIS  iii  electric-control  systems,  the  buttons  are 


GASOLINE  AUTOMOBILES  395 

Pneumatic  Shifting  System.  The  pneumatic  system  of  gear 
shifting  is  along  lines  somewhat  similar  to  the  electric  system,  air 
under  pressure  being  used  to  move  the  gears  instead  of 'a  hand  lever 
and  rod  combination.  For  this  purpose  it  is  necessary  to  add  an 
air  compressor,  a  tank  to  carry  the  compressed  air,  and  what  is 
called  the  "shift" — really  a  complicated  valve  and  a  series  of  plungers 
. — to  the  car.  The  valve  and  plungers  respond  to  a  finger  lever  on  the 
steering  wheel,  the  same  as  the  electric  system  responds  to  the  but- 
tons. Air  is  admitted  behind  the  plungers,  which  moves  the  gears 
as  soon  as  the  clutch  is  depressed.  It  is  seen,  therefore,  that  this 
system,  like  the  electric  shifter,  permits  the  anticipation  of  the 
needs  of  the  car. 

Railway  Car  Needs.  All  transmissions  previously  presented 
have  had  but  one  reverse.  For  gasoline  railway  cars,  the  inability 
to  turn  the  car  requires  as  many  reverse  speeds  as  forward,  which 
means  special  gearing.  Usually,  this  gearing  is  accomplished  by 
means  of  a  pair  of  bevels,  each  with  a  clutch,  meshing  with  a  single 
driving  bevel.  Obviously  the  two  driven  bevels  will  turn  in  different 
directions,  and  each  will  drive  when  its  clutch  is  engaged.  By 
shifting  the  clutch  to  the  one  which  gives  a  for^-ard  speed,  all  the 
speeds  of  the  gear  box  become  forward  speeds;  by  shifting  to  the  one 
which  gives  reverse,  all  the  speeds  become  reverse  speeds. 

INDIVIDUAL  CLUTCH 

Qeneral  Types  Used.  While  the  number  of  adherents  to  the 
individual-clutch  type  of  transmission  is  not  as  great  as  that  of  either 
the  progressive  or  selective  types  of  sliding  gear,  it  holds  its  own; 
and,  as  time  passes,  it  gains  adherents.  In  this  form,  all  the  gears 
are  in  mesh  at  all  times,  and  what  has  been  called  "the  barbarous 
and  unmechanical"  method  of  clashing  gears  is  entirely  done  away 
with.  The  individual-clutch  type  is  operated  on  the  selective  plan 
but  otherwise  has  nothing  in  common  with  the  latter. 

The  forms  of  clutches  used  vary  greatly,  as  might  be  expected. 
The  following  are  in  use  today:  jaw  clutches  (both  two-  and 
multiple-jaw);  internal-external  gears,  multiple  disc,  cone,  and 
friction  clutches  other  than  the. multiple-disc  form. 

a 

Using  Internal  Dogs.  One  type  in  which  the  gears  are  engaged 
by  internal  dogs — ^the  gears  being  in  mesh  at  all  times — ^has  four  sets 


396 


GASOLINE  AUTOMOBILES 


of  gears,  those  on  the  main  shaft  being  keyed  or  otherwise  fixed  to  I 
the  shaft,  while  the  gears  on  the  jackshaft  nm  idle  except  when  tfao  I 
gear-shifting  lever  is  moved  forward  to  an  engaging  pontion,  wbiA 
throws  an  internal  dog  up  into  a  slot  inside  the  gear.  T\ua  positioD  | 
makes  the  gear  one  with  the  ^laft,  and  the  power  is  transmitted  I 
directly.  The  dogs  in  the  latest  form  of  this  traasmissioa  take  the  | 
form  of  hardened  and  ground  steel  balls.  • 

Disc  Type.    Many  of  the  eariy  individual  clutdi  types  of  trans-    I 
missions  used  discs,  each  gear  having  its  own  set  and  each  set  having 
sufficient  surface  to  carry  the  whole  power  of  the  motor.     While 
bulky,  this  had  undeniable  advantages,  for  it  aUowed  starting  on    < 
any  gear. 

Contrncting-Band  Type.    While  advocates  of  discs  are  numerous, 
other  devices  do  not  lack  friends.    Hg.  284  shows  a  form  on  the 
Haynf5-Appcr:'nn| 


GASOLINE  AUTOMOBILES  397 

.gainst  the  gear  by  means  of  numerous  fingers,  Fig.  285.  A  conical 
tiding  piece  G  or  J  expanded  the  fingers  pivoted  on  M  and  H  so  that 
hey  pressed  against  the 
Use  within  tiie  gears  D, 
K,  or  N. 

Internal' External  Gear 
Type.  Many  of  the  gears 
.Iready  given  date  back 
everal  years,  but  the 
;ear  illustrated  in  Fig. 
186  is  more  modem, 
.nd  is  being  used  today 
I  y  the  International 
dotor  Company  of  New  York  City  and  of  AUentown,  Pennsylvania. 
-The  principle  upon  which  this  gear  works,  as  shown  by  Fig.  286, 
3  that  of  the  internal-external  gear.  The  gears  which  transmit  the 
tower  are  always  in  mesh.  Each  one  of  these  is  bushed  and  runs  idly 
ipon  the  main  shaft.  Contained  within  each  gear  and  an  integral 
«art  of  it  is  an  internal  gear  of  twenty-four  teeth.     Sliding  on  the 


quared  shaft  are  four  24-tooth  gears;  these  are  specially  built  for  easy 
ngaging  with  the  internally  cut  gears. 

To  follow  the  letters  placed  on  the  parts  of  th\s  %eaiT,V\^  «^^ 


3d8  GASOLINE  AUTOMOBILES 

is  obtained  b\-  sliding  the  piece  £-C~31  forward  into  gear  3-C-3i; 
this  action  swings  the  piece,  shown  dotted  beneath,  so  as  to  throw 
out  the  clutch  on  the  {ay  shaft  2-C~52.  On  high  speed,  the  two  gears 
locked  together  arc  the  only  ones  to  turn,  all  others  being  idle.  The 
same  piece  3-('~31,  when  slid  to  the  right,  meshes  with  the  internal 
gear  of  the  ■ictf>nd -speed  pinion  2-C-160.  This  shding  member  sltdts 
upon  H  squared  shaft,  so  the  drive  is  poMtive,  The  action  of  the  first, 
or  slow  s[)ccd.  and  reverse  are  the  same  as  those  just  described,  beinj! 
profiuced  by  the  shifting  of  the  clutch  member  2-C-66.  Attention  is 
called  tn  tiie  ball  bearings  used  on  this  transmission,  which  are 
reniarkubleonly  when  it  is  remembered  that  this  is  a  commercial  truck 
transmission,  Students  of  automobile  construction  will  find  many 
intcrc'stiiig  constructional  details  in  this  illustration,  which  is  a  repro- 
duction of  the  manufacturer's  working  drawing. 

Still  iiniitlitT  sLiniliir  form  uses  three  cone  clutches  in  the  tfans- 
mission,  that  for  the  iiinh  speed  being  augmented  by  a  set  of  pins, 
or  (logs,  which,  as  the  i-lutch  gradually  takes  hold,  slip  into  an  equal 
number  of  holes  in  the  ilriven  gear.  In  this  way,  tlie  two  are  made 
as  oi)e,  whifli  makes  slipping  impossible— a  very  important  feature. 

Transmission  Operation.  As  has  been  pointed  out  previously, 
|)raiti<;illy  all  transmissions  operate  all  gears  by  means  of  a  long  hand 


GASOLINE  AUTOMOBILES  399 

which  loss  of  power  shoilld  be  avoided.  Gear-box  lubricant  generally 
is  introduced  in  bulk  by  the  removal  of  the  cover,  usually  of  a  large  size 
to  allow  of  this.    The  outside  parts  carry  their  own  grease  and  on  cups. 

Transmissioii  Bearings.  By  looking  back  at  the  various  trans- 
missions shown,  it  will  be  noted  that  ball  bearings  are  used  most 
freely.  Roller  bearings  in  various  forms  are  coming  into  use,  as  the 
shorter  series  produced  in  the  last  couple  of  years  has  shown 
designers  that  thist  ype  would  produce  a  compact  gear  box,  their  size 
having  previously  limited  their  use.  Plain  bearings  are  not  used  at 
all  on  good  cars. 

Transmission  Adjustments.  Few  adjustments  are  needed  in 
the  modem  gear  box.  However,  provision  for  wear  is  made  in  the 
operating  rods  and  levers,  both  within  the  case  and  without.  In 
some  cases  the  shafts  may  be  slightly  shifted  endwise  to  secure 
better  meshing  of  the  gears  after  wear.  Bearings,  too,  are  arranged 
to  shift  slightly  in  an  endwise  direction  to  take  care  of  wear  in  other 
parts  and  not  so  much  in  the  bearings  themselves. 

PLANETARY  GEARS 

Method  of  Action.  The  planetary,  or  epicyclic,  form  of  gear- 
ing offers  many  advantages,  but,  strange  to  say,  the  American 
people,  although  inclined  toward  simplicity  and  cheapness  in  com- 
bination, will  not  have  it  in  this  form,  and,  as  a  consequence,  this 
excellent  gear-reducing  means  is  fast  losing  favor.  The  principle 
upon  which  all  planetaries  work  is  as  follows:  Connected  to  the 
engine  is  the  first  gear  of  the  train.  The  second  is  one  of  a  series  of 
several  gears;  these  are  pivoted  in  a  drum,  which  may  be  held  station- 
ary by  a  brake  band.  The  middle,  or  third,  gear  in  the  train,  as  well 
as  the  last,  or  fourth,  is  connected  to  another  gear,  a  driven  gear,  not  a 
driver.  Considering  but  a  single  rotating  train — there  usually  are 
three  or  more — the  last-named  gears  form  the  fifth  and  sixth  in  the 
whole  train.  Gears  two,  three,  and  four  have  different  numbers  of 
teeth,  as  well  as  gears  one,  five,  and  six.  Holding  the  band  which 
holds  the  drum  to  which  the  gears  are  pivoted,  allows  each  of  them 
to  rotate  around  its  own  axis,  but  not  around  the  main  shaft.  This 
form  of  rotation  gives  one  gear  reduction. 

Another  band  holds  another  gear  stationary  and  allows  the 
three-gear  unit  to  rotate  around  the  main  shaft  as  an  axis;  at  the 


400 


(JAriOUNE  AVTUMOBILKS 


sani«  titDP  it  liraves  tbL-m  frcv  to  nlso  nitattr  HrrHnxl  llictr  own  iixrv 
This  prodiioei  another  fiear  mluction.  ^Vnuttur  form  which  is 
popular  in  so  far  as  plaiu-tar>'  g«ftr»  tirr  [wpulnr  k>  tlut  in  v\\]A 
tntenial  gf-ars  are  ^ubstitutM  tor  noe  9ct  of  the  jdaiiKU,  from  wbiiii 
Uie  device  ubtainetl  its  name.  This  <liws  itoi  roniplicnte  ihr  fk^icc 
any;  in  fact,  ttu-  only  way  in  which  it  makes  any  change  ia  in  thr 


GASOLINE  AUTOMOBILES 


401 


FRICTION  DISC 

ubtedly,  when  simplicity  ia  sought  regardless  of  cost,  the 
ive  is  the  drive  used.     The  cost  with  this  form  is  not  one 

but  rather  of  other  things  which  must  be  sacrificed  if 
ive  is  used. 

Type.  In  the  interest  of  simplicity,  it  may  be  said  that 
n  form  of  drive  dispenses  with  the  clutch,  being  of  itself 
h  and  change-speed  gear.  The  usual  form  which  this  takes 
g!e  spur  wheel  contacting  with  another  flat-face  wheel, 
e  must  be  i»t  right  angles,  the  car  is  nearly  always  chain 
!  driving  wheel 
be  rear  end  of 
ihaft,  and  the 
tft  across  the 

the  car.      To 

more  certain 
at  the  same 
in  the  differ- 
on,  the  cross-, 
nted  upon  two 
nt  shafts,  is 
d  with  a  pair 
3,  contacting 
}site  sides  of 
;r.  As  this 
luses  the  two 
ifts  to  turn  in 

lirections,  a  gear  is  necessary-  at  the  end  of  one  of  them, 
p^atest  feature  of  the  friction  drive  is  the  multiplicity  of 
tainable,  these  being  Infinite  in  number,  since  every  dif- 
ition  of  the  driven  wheel  on  the  dri\cr  rcsult-s  in  a  different 

consequently,  a  different  speed.  To  obtain  these  various 
he  wheel  which  meets  the  other  edge-on  is  usually  arranged 
meed  up  to  and  withdrawn  fn>m  the  wheel  presenting  the 
e.  In  action,  a  motion  of  translation  is  given  tu  the  wheel 
le  time  as  the  motion  up  to  or  away  from  the  surface.  This 
'  translation  changes  its  position  and  cooscqueotly  its 


H 


402  GASOLINE  AUTOMOBILES 

Over  the  threowheel  arrangement,  the  use  of  the  four-wheei 
arrangement  possesses  some  undeniable  advantages,  particulari,;-  if 
the  two  parallel  driving  wlieels  are  arranged  to  (i^i^■e  the  others  in 
pairs.  This  arrangement  makes  tlie  (Hrectinii  of  rotation  of  the 
wheels  alike,  and  no  intermediate  gear  to  change  the  direction  of  one 
shaft  is  needed.  A  siaiplificatiou  of  this  form  utilizes  the  flywheel  of 
the  engine  as  the  forward  driving  disc. 

Bevel  Type.  Bevels  have  many  advantages  over  spur  friction 
wheels.  They  are  found  in  combinations,  such  as  a  single  pair  of 
bevels  or  three  bevels,  and  in  multiple  combinations,  without  limit  to 
the  number  of  bevels.  Fig,  288  shows  the  use  of  a  single  pair,  hut 
in  combination  with  a  flat  face  on  one  and  a  spur  attached  to  the 
other;  this  makes  the  whole  consist  of  four  wheels  in  reality. 

Another  combination  sometimes  used  is  that  of  three  bevels. 
One  of  the  bevels  has  a  flat  face  and  a  spur,  making  really  five  wheels. 
The  spur  wheel  in  e\'ery  case  takes  the  final  drive,  A  direct  drive 
on  the  high  gear  is  obtained  by  the  use  of  a  cone  clutch  on  this  spur 
and  another  clutch  with  which  it  engages  on  the  driving  wheel.  One 
bevel  gives  forward  speeds,  and  through  the  other  the  various  reverses 
are  gained.     The  frirti<jn  drive,  although  theoretically  the  simplest 


GASOLINE  AUTOMOBILES  403 

buggy  field,  the  rope  drive,  the  flat  belt,  the  V-belt,  the  cloth-covered 
chain,  and  many  others.  With  the  collapse  of  the  cycle-car  boom, 
these  went  out  of  use. 

Hydraulic  Qear.  Janney-Williams,  The  hydraulic  transmis- 
sion has  been  advanced  as  a  cure  for  all  automobile  troubles,  rep- 
resenting as  it  does  the  elimination  of  clutch,  differential,  and  the 
driving  mechanism.  It  consists  of  a  pump  to  circulate  the  fluid,  and 
one  or  two  motors,  usually  attached  to  the  rear  wheels  and  propelled 
by  the  fluid.  In  the  Janney-Williams  hydraulic  gear,  which  has 
been  successfully  used  for  some  time  in  other  fields,  but  has  just 
recently  been  tried  for  automobiles  in  England,  there  are  three 
similar  pumps,  one  being  used  as  a  pump  and  the  other  two  as  motors. 
By  rotating  the  driving  ring  so  that  it  assumes  different  angular 
positions,  the  throw  of  the  small  pistons,  of  which  there  are  nine  in 
all,  is  varied  from  zero  up  to  a  maximum.  Since  the  action  of  the 
fluid  in  the  motors  connected  to  the  wheels  is  opposite  to  this,  it 
amounts  to  varying  the  speed,  the  number  of  changes  being  infinite, 
as  in  friction  gearing. 

Manly,  Another  hydraulic  drive,  of  equal  merit  and  of  Ameri- 
can manufacture,  is  the  Manly.  This  differs  from  the  Janney- 
Williams  only  in  the  form  of  the  motors;  the  fluid  and  its  use  are  the 
same  in  both  cases.  This  drive  has  for  its  object  the  securing  of  any 
desired  speed  of  the  driven  shaft,  either  forward  or  backward,  with- 
out changing  the  speed  or  direction  of  motion  of  the  driving  shaft 
and  of  transmitting  the  power  to  a  shaft,  which  is  either  in  line  with 
the  driving  shaft  or  which  lies  at  any  angle  to  the  driving  shaft  and 
is  separated  from  it.  It  consists  of  a  multi-cylinder  pump  having  a 
variable  stroke,  which  is  attached  to  the  driving  shaft,  and  of  one  or 
more  multi-cylinder  motors  having  a  fixed  stroke,  which  are  attached 
to  the  driven  shaft,  together  with  pipe  connections,  or  passages, 
between  them  for  transmitting  the  working  iield.  The  various 
cylinders,  both  of  the  pump  and  motors,  radiate  equidistantly  from 
a  central  crank  chamber,  and  the  pistons  or  plungers  are  connected 
to  a  single  crankpin  which  is  common  to  all.  The  fluid  used  is 
ordinary  machine  oil,  its  lubricating  qualities  and  freedom  from  the 
danger  of  freezing  admirably  fitting  it  for  such  a  purpose.  When  the 
system  is  once  filled,  the  oil  is  used  over  and  over  agaiu,  bra^^Vsvesstv- 
tinuous  circulation  from  pump  to  motor  througVi  one  set  ol  ^^^^^^  «^ 


404  GASOLINE  AUTOMOBILES 

passages,  and  hack  again  from  motor  to  pump  through  aiuitluT  srt. 
The  stroke  of  the  puiuii  rnn.v  W  varied  Ht  will,  hiil  timt  of  tlic  motor 
is  fixed.  The  variation  of  the  pump  stroke  iH  ac-i'onipli.thetl  liy  a 
crank,  on  which  an  eect^ntrie  bushing  is  mountw!,  By  revolving  the 
bushing  with  reference  to  the  crank,  ita  center  line  is  hrought  into 
alignment  with  the  center  of  the  shaft,  and  when  this  position  is 
reached,  no  reciprocating  motion  is  communicated  to  the  pump 
plungers.  The  Manly  is  constructed  iimler  license  by  the  American- 
La  France  Fire  P'ngiiie  Company,  Rlmira,  New  York,  and  has  proved 
its  worth  on  \ery  large  trucks  and  on  some  of  (heir  fire  apparatus. 

In  recent  jears  a  number  of  hydraulic  transmis.<)ions  have  been 
brought  out.  but  all  these  fact^  the  fundanientul  rfifBcuIty  that  when 
the  pump  chamber  is  liquid  tight  the  friction  is  excessive. 

Pneumatic  Drive.  There  bus  been  some  talk  of  a  pneumatic 
drive  also,  this  idea  not  differing  greatly  from  the  previous  one  of 
using  liquids.  In  this  scheme  H  large  tjink  of  compresMxl  air  is 
pnwidcd  for  the  purjjose  of  starting  the  engine,  helping  to  get  up 
spi'cd  quickly,  and  for  use  on  hills  when  excess  power  is  needful 
or  at  least  helpful.  If  used  as  planned,  it  would  allow  of  the  elim- ' 
ination  tif  the  reverse  and  would  be  utilized  for  braking  aa  weU, 


GASOLINE  AUTOMOBILES 


405 


In  fact,  it  might  be  said  that  the  electric  drive  possesses  so  many 
advantages  which  are  worth  liaviiig,  even  at  a  sacrifice,  and  so  few 
disadvantages  that  one  is  safe  in  figuring  that  a  few  more  years 
will  see  the  number  of  these  drives  double^  and  possibly  trebled. 

Electric  Transmissions.  While  the  drives  just  discussed  might 
be  called  electric  dri^■e8  and  still  be  precise,  the  Owen  magnetic  car, 
which  is  constructed  by  the  Baker,  Ranch  and  Lang  Company, 
makes  use  of  an  actual  electric  transmission,  the  Entz,  at  one  time 
used  in  a  Columbia  chassis.  This  is  so  arranged  that  all  speed 
changing  is  done  by  a  small  finger  lever  on  the  steering  wheel,  similar 
to  the  ordinary  spark  and  throttle  levers.     The  wiring  formerly  gave 


<tea- 


Fic  18B.     Drawiu  Shoinng  SectioD  through  Oweo  Mi 


seven  speeds  forward  and  two  reverse,  but  a  later  construction  will 
probably  give  about  twice  this  number. 

As  is  shown  in  Fig.  289,  this  consists  of  an  electric  generator,  the 
field  magnet  of  which  is  connected  to  the  engine  crankshaft  and  takes 
the  place  of  the  flj-wheel,  the  armature  being  connected  with  the 
driving  shaft.  This  transmits  the  turning  effort  of  the  engine  by 
means  of  the  current  established  in  its  circuit,  due  to  the  speed 
difference  of  its  members  on  what  constitutes  the  high  speed.  Any 
effort  exerted  by  the  engine  on  one  member  is  transmitted,  prac- 
tically without  loss,  to  the  other  member,  or  armature.  The  clutch- 
generator  member  makes  a  very  elastic  clutching  and  tc&n^^'Uxnf, 
means,  but  caonot  traasmit  more  than  the  fuU  torque  ol  x!t\%  «t\^vi.%- 


406  GASOLINE  AUTOMOBILES 

Fur  higher  torque,  use  is  made  of  an  electric  motor,  whose 
armature  is  mounted  on  the  driving  shaft  and  receives  current  from 
the  first,  or  clutch,  generator. 

In  the  figure,  tlic  clutch  generator  is  shown  at  the  left,  its  field 
part  marked  FR,  the  field  winding  FW,  and  the  pole  pieces  PP. 
This  portion  rotates  whenever  the  crankshaft  revolves.  Within  it  is 
the  armature  .1  secured  to  the  continuous  shaft  S,  which  is  con- 
nected througli  the  joint  A'  with  the  driving  shaft  to  the  rear  axle. 

Tlic  second  part  of  the  complete  sj-stem  is  shown  at  the  right 
ani]  is  practically  a  duplicate  of  the  clutch  generator.  Its  armature 
,'li  is  carried  on  the  same  shaft  S  as  armature  A.  Outside  this  is 
the  usual  field  part  with  rings  FR,  windings  FW,  pole  pieces,  and 
brushes  B. 

Field  FR  can  revolve  without  any  motion  of  A ;  in  fact,  it  is  by 
varying  the  relative  speed  of  FR  and  ,1  that  the  different  speeds  are 


GASOLINE  AUTOMOBILES 


407 


parable  to  the  piece  of  steel  f ',  which  is  free  to  rotate  and  which  will 
do  so  when  the  field  rotates  and  attracts  it.  If  this  were  connected 
directly  to  the  driving  shaft,  as  Fig.  290  shows   the  combination 


Fl|.  201.     SbooimI  Step 


would  become  a  simple  electromagnetic  clutch  and  the  car  would  have 
but  one  speed.  On  the  level,  one  speed  would  be  satisfactory,  but 
in  deep  sand,  on  a  heavy  grade,  or  for  any  other  severe  pull,  the  air 
space  between  the  rotating  field  and  the  armature  would  bring  about 
the  stalling  of  the  engine. 


If  we  add  a  ccnventional 
electric  motor  just  back  of 
C,  with  its  field  fixed,  or 
stationary,  as  at  D.  and  its 
armature  free  to  rotate  with 
the  armature  shaft  to  which 
it  b  attached,  about  as  shown 
in  Fig.  291,  C  will  not  rotate 
as  fast  as  B  when  meeting  a 
stiff  pull,  although  it  will  try 
to  do  so.  A  wire  connects 
the  commutator  of  C  with 
the  field  coils  D,  and  the 
electricity  generated  by  the 
rotation  of  B  relative  to  C,  that 
air  gap,  is  led  through  this  wire  to  D  where  It  acta  aa  power,  rotating, 
E  faster  and  thus  acting  as  a  booster  on  the  propeWec  ^VitAl. 


,  the  amount  of  slippage  due  to  the 


GASOLINE  AUTOMOBILES 


GASOLINE  AUTOMOBILES  409 

By  introducing  variable  resistaiic-e  in  the  connecting  wire,  or 
ther  series  of  wires,  the  speed  may  be  varied  from  zero  to  the 
Aximmn,  which,  as  it  happens  through  this  booster  action,  is 
nsiderably  in  excess  of  what  it  would  be  if  the  motor  were  dri\'ing 
rectly  through  on  high  speed  without  any  electrical  or  mechanical 
^paratus.  The  variety  of  speeds  can  be  an\-thing  desired,  and  this 
rms  the  basis  for  naming  it  **The  car  of  a  thousand  speeds".  As 
matter  of  fact  only  seven  speeds  are  provided  for  on  the  steering 
leel,  which  is  shown  in  Fig.  292,  but  it  is  perfectly  feasible  to 
re  up  the  car  and  arrange  the  quadrant  to  have  twice  this  number 

any  other  number,  as  required.  On  the  steering  post  quadrant, 
e  additional  positions  of  charging,  starting,  and  neutral  are  to 

noted.  The  neutral  position  is  that  in  which  the  engine  is  idling 
id  the  car  standing  still;  or  when  the  car  is  coming  down  a  grade, 
e  wheels  are  driving  the  motor  which  generates  current  in  the  reverse 
rection,  so  that  the  device  becomes  an  electric  brake,  slowly  but 
rely  reducing  the  speed  of  the  can  The  starting  position  connects 
e  storage  battery  to  the  generator  armature  in  order  to  revolve 
e  engine  shaft  and  thus  start  it.  The  charging  position  can  be 
ed  at  any  time  to  generate  electricity  for  the  storage  battery. 
WTiile  this  description  sounds  verj'  different,  the  chassis  is  not 
ilike  the  avera^  gasoline  chassis  with  a  mechanical  gear  shift. 

Fig.  293,  showing  a  view  of  it  from  above,  brings  out.  The  small 
lit  just  back  of  the  motor  is  a  mechanical  reverse  gear  which  it 
.s  been  found  advisable  to  use  for  one  reason,  because  it  gives 
I  the  quadrant  speeds  on  the  reverse,  instead  of  the  usual  one. 
y'  this  arrangement  the  car  has  seven  fixed  speeds  forward  and 
ven  speeds  reverse,  together  with  the  possible  variations  of  both, 
lich  can  be  produced  by  the  use  of  spark  throttle  and  accelerator. 

TRANSMISSION  TROUBLES  AND   REPAIRS 

Noise  in  Qear  Operation.  One  of  the  most  common  of  trans- 
ission  troubles  is  a  grinding  noise  in  the  operation  of  the  gekrs. 
lis  is  heard  more  in  bevels  than  in  spurs,  but  in  old  transmissions 
id  on  the  lower  speeds  it  is  heard  frequently.  A  good  way  to 
liet  old  gears,  after  making  sure  that  they  are  adjusted  rightly 
d  meshing  correctly,  is  to  use  a  thicker  lubricant.  If  thick  oil 
being  used,  change  to  haJf-oiJ  and  half-grease  or  pTii\eT«Jc\x  ^  ^^^^$fc. 


410  GASOLINE  AUTOMOBILES 

III  this  rcspcft  tlie  repair  man  or  amateur  worker  may  take  a    ; 
Ifjif  «iiit  (if  tlie  l«Hik  of  second-hand  car  men,  who  are  said  to  "load"    i 
an  old  and  very  noisy  transmission  gear  with  a  very  thick  almost    , 
hard  grease  in  which  is  mixed  some  shavings,  sawdust,  cork,  or   , 
similar  lieadening;  material.     When  this  is  done,  a  graphite  grease  is    ■ 
;;enerully  used,  so  that  the  shavings,  cork,  etc.,  would  not  show  in 
case  it  was  necessary  tii  take  off  the  gear-fwx  cover.     This  material 
Mill  fill  nj)  all  the  inequalities  of  the  gears  and  shafts  so  that  tem- 
Iirirarily  evcrvthing  fits  more  tightly,  and  all   the  sounding  board, 
or  echo,  cfTcct  i--  t.ikm  out  of  the  transmission  case,     This  sounding- 
hoard  clfcit  is  fnlh   as  important  as  the  grinding  noise,  for  many 
rc;dly  iiisignihc  ml  noisi-,  are  magnifietl  by  poorly  shaped  gear  eases 


GASOLINE  AUTOMOBILES 


411 


Gear  PuUra^.  One  of  the  principal  necessities  for  transmission 
}rk  is  8  form  of  gear  puller.  These  are  like  wheel  pullers,  except 
at  they  are  smaller  and  more  compact.  In  Fig.  294,  a  pair  of 
ar  pullers  are  shown.  The  one  at  the  left  is  very  simple,  consisting 
a  heavy  square  bar  of  iron  which  has  been  bent  to  form  a  modified 

Then,  a  heavy  bolt  is  threaded  into  the  back  of  this  or  bottom  of 
e  U.  This  will  be  useful  only  on  gears  which  are  small  enough  to 
'  in  between  the  two  sides  of  the  puller,  that  is,  between  the  sides 
the  U,  which  when  in  uae  is  slipped  over  the  gear,  the  screw  turned 
itil  it  touches  some- 
ing  solid,  as  the  end  of 
e  gear  shaft,  and  then 
e  turning  continued 
ntil  the  gear  is 
reed  off. 

While  not  as  simple 
this,  the  form  shown 

the  right  has  the 
Ivantagcs  of  handling 
uch  larger  gears,  and 
so  of  being  adjustable. 
3  the  sketch  shows,  this 
insists  of  a  central 
ember  having  slotted 
ids  in  which  a  pair  of 
.shaped  ends,  or  hooks, 
e  held  by  a  pair  of 
rough  bolts.  Then 
ere  is  a  central  work- 
g  screw.  To  use,  the  hooks  are  set  far  enough  apart  to  go  over  the 
«r,  then  slipped  around  it  and  hooked  on  the  back.  The  central 
rew  is  turned  up  to  the  end  of  the  shaft,  and  then  the  turning 
tntinued  until  the  gear  comes  off.  There  are  many  modifications 
'  these  two;  in  fact,  practically  every  repair  shop  in  the  land  has 
i  own  way  of  making  gear  or  wheel  pullers.  At  any  rate,  everj' 
lop  should  have  one. 

Pressing  Qears  on  Shafts.  The  opposite  of  pulling  off  gears 
putting  them  on;  very  often  they  are  designed  to  \ie  a.  ■^tcss.  ^^-x 


Fie.  29G.     Mctbod  o[  Ptaung  Tmumiuion  Gttt 


OAtfOLINE  AUTOMOBILES 

whicli  means  exerting  tremendous  pressure.  Every  repair  shop 
shouiii  have  some  form  of  press  for  this  and  similar  work,  something 
similar  to  the  form  shown  in  Fig.  295.  In  this  figure,  the  man  is  just 
begiiming  to  apply  pressure  to  the  shaft  to  force  it  into  the  lower 
j;ear.  The  table  must  be  arranged  for  work  of  this  kind  with  a  solid 
spot  when  the  shaft  does  not  come  through,  and  with  a  hole  when  it 
does.  The  work  of  pressing  is  usually  done  in  a  few  seconds,  while  the* 
preparHtion,  atigninent,  and  starting  of  the  work  takes  perhaps  half 
nil  hour  or  more.  It  is  work  which  should  be  done  very  carefully. 
One  way  in  which  arrangement  can  be  made  for  pressing  a 
shaft  a  coiisidcTiiliic  dislaiice  into  a  gear  and,  conversely,  for  pressing 
the  shaft  out  of  the  gear  is  that 
shown  in  Fig.  296.  This  figure 
has  the  additional  advantages  of 
being  simple,  easily  constructed, 
and  cheap.  A  solid  base  is 
constructed  with  a  pair  of 
hinged  uprights.  These  can  be 
dropp)ed  together  with  the  work 
them,  forming  a  mod- 
ed     triiingle,     the     strongest 


GASOUNE  AUTOMOBILES 


413 


For  one  thing,  the  edges  of  the  gears  may  be  burred  so  that  the  edges 
prevent  easy  meshing.  When  this  is  the  case,  any  attempt  to  force 
the  gears  into  mesh  only  burrs  up  more  metal  and  makes  the  situa- 
tion worse.  Whether  this  is  the  trouble  or  not  can  be  determined 
very  quickly  and  easily  by  removing  the  transmission  cover  and 
feehng  of  the  gears  with  the  bare  hand;  the  burred  edges  can  readily 
be  distinguished.  If  this  is  the  only  fault,  the  transmission  should 
be  taken  down,  the  gears  taken  out  and  placed  in  a  vise,  and  the 
burrs  removed  with  a  cold 
chisel  and  file. 

Poor  or  worn  bear- 
ings or  a  bent  shaft  or  one 
not  accurately  machined 
may  cause  difficult  shift- 
ing. If  the  bearings  are 
worn,  the  difficulty  of 
shifting  nill  be  accom 
panied  b\  much  noise 
both  in  shifting  and  after 
The  bent  shaft  is  more 
difficult  to  find  and  equall> 
difficult  to  fix  A  new  ^ 
shaft  IS  usualh  the  quick 
est  and  easiest  way  to 
remedy  the  trouble 

Sometimes  the  con 
trol  rods  or  levers  bind  or 
stick  so  that  the  shifting 
is  very  difficult.  In  case 
the  gears  are  difficult  to 
"find"  or  will  not  stay  in  mesh,  the  fault  may  be  in  the  shifter  nxl.in 
the  transmission  case.  This  usually  has  notches  to  correspond  to  the 
various  gear  positions,  with  a  steel  wedge  held  down  into  these  notches 
by  means  of  a  spri&g.  The  spring  may  have  weakened,  may  have  lost 
its  temper,  may  have  broken,  or  for  some  other  reason  failed  to  work. 
Or  with  the  spring  in  good  working  condition,  the  edges  of  the 
grooves  or  notches  may  have  worn  to  such  an  extent  as  to  let  the 
wedge  slip  out  of,  or  over,'  them  readily. 


4U 


GASOLINE  AUTOMOBILES 


Cleaning  Transmission  Gears.  When  tliu  transmission  is  taken 
out  of  tiie  case  uml  has  to  be  taken  apart,  ami  particularly  if  it  lias 
not  been  cleaned  fnr  a  long  time  previously,  it  is  advisable  to  clean 
all  the  parts  thoroughly  before  attempting  to  work  with  them. 
The  best  way  to  clean  the  parts  is  to  have  a  special  cleaning  tank. 
In  Fig.  297  one  of  these  is  shown,  which  is  not  unlike  the  baskets 
used  in  some  hardening  processes.  It  consists  of  a  deep  metal  or 
metal-lined  tank  and  a  basket  or  tray,  which  is  an  easy  fit  in  it, 
sus(>endeiJ   from   abo\'e   by   wire  cables.     The  cables  arc   brought 


GASOUNE  AUTOMOBILES  415 

drain,  all  trace  of  kerosene  will  disappear,  while  the  gears,  shafts, 
and  other  part^  will  be  like  new. 

Lifting  Out  Transmissions.  When  the  trouble  has  been  found 
to  be  in  the  transmission  case  or  in  some  part  that  necessitates  com- 
plete removal,  it  is  often  a  tremendous  job  to  get  the  unit  out.  Some 
units  are  attached  from  below  and  are  not  so  difficult  to  detach. 
TTiey  are  lowered  by  means  of  a  platform  of  boards  set  on  two  or 
more  jacks;  But  when'  it  must  be  removed  from  above  and  uo 
overhead  beam  is  available,  the  hoist  shown  in  Fig.  298  will  be  found 
very  handy.  As  will  be  seen  from  the  sketch,  this  hoist  is  simply  a 
triangular  framework  constructed  from  angle  iron  to  have  the 
minimum  height  which  will  allow  removal  of  the  unit.    The  chain 


Tit-  200.     Ti 


fall  is  attached  to  a  hook  in  the  center,  and  the  chains  put  around 
the  case.  When  lifted  up  close  into  the  V  of  the  framework,  the 
whole  transmission  can  be'put  onto  horses  and  moved  along  the 
chassis,  or  boards  can  be  put  under  it  and  over  the  chassis  frame  to 
allow  it  to  be  worked  there.  Or,  if  desired,  it  can  be  lowered  onto  a 
creeper  or  other  low  platform  with  wheels  and  moved  out  of  the  way. 
This  rising  can  be  used  for  many  other  similar  purposes,  although  it 
is  not  suitable  for  the  removal  of  an  engine,  radiator,  or  other  part 
or  unit  which  extends  far  above  the  chassis  frame. 

Transmission  Stands.  When  the  transmission  has  been 
removed,  if  the  work  to  be  done  upon  it  is  all  extended,  a  stand  to 
support  it  is  desirable;  in  fact,  a  necessity,  if  the  work  is  to  be  done, 
right.    A  pair  of  stands  are  shown  in  Fig.  299,  l\ie  otve  aX  \li\«\^X 


41ft 


GASOLINE  AUTOMOBILES 


is  made  from  pipe  fittings  and  angle  irons  in  such  a  way  that  the 
width  between  the  rails  can  be  varied  to  suit  the  transmission  or 
engine.  The  stand  at  the  right  is  more  of  a  specialized  type.  It  is 
constructed  for  a  certain  transmission  and  has  clips  to  support  it 
in  the  same  way  that  it  is  held  in  the  chassis.  The  latter  frame  may  be 
smaller  and  more  compact  than  the  former,  but  the  wide  range  of 
uses  to  which  the  former  can  be  put  make  it  more  desirable  in  the 
average  shop. 

Working  in  Bearings.  When  a  great  many  bearings  of  an\' 
one  transmission  are  fitted,  it  is  well  to  make  a  jig  for  working  in 
the  cases  to  an  exact  size  for  the  bearings,  whether  these  be  over- 


^m»^ 


Fie.  300.     Method  ol  flttiua  Tmumi 


.^  A 


sizes  or  not.  Such  an  outfit.  Fig.  30(),  ^hows  an  aluminum  trans- 
mission case  with  a  pair  of  jigs  for  scraping  its  bearings  into  the  case. 
These  jigs  are  made  of  steel  and  are  constructed  to  a  very  accurate 
size,  the  surfaces  being  hardened  so  tliey  will  show  no  wear.  The 
jigs  are  painted  with  Prussian  blue,  put  in  place  and  turned,  the 
markings  scraped  by  hand,  the  jigs  again  put  in  place  and  turned, 
and  this  process  repeated  until  a  perfect  bearing  surface  is  obtained. 
Starting  with  an  imknnwn  size  on  tlic  case  and  a  known  size  of  bearing 
which  must  go  in  it,  a  few  of  these  jigs  will  soon  save  their  cost  in 
labor  and  time,  by  quickly  \>rod\iciiig  the  necessary  size  of  case  to 
take  the  bearings. 


GASOLINE  AUTOMOBILES 


417 


>  Saving  the  Balls.  If  a  great  many  ball  bearings,  particularly 
from  transmissions,  are  used,  and  many  bearings  scrapped,  it  is 
advisable  to  save  the  balls.  These  balls  will  come  in  handy  later  for 
replacement  or  other  uses. 
Moreover,  balls  are  expen- 
sive, and  good  ones  are  hard 
to  obtain.  A  handy  way  to 
take  care  of  balls,  without 
much  work  beyond  cleaning 
thoroughly  in  the  kerosene 
tank,  is  to  construct  a  cab- 
inet like  that  seen  in  Fig.  301 . 
There  are  four  drawers — or 
more  if  desired.  The  bottom 
of  each  drawer  isa  steel  plate 
drilled  as  full  of  holes  as  pos- 
sible of  the  next  smaller  size, 
that  is,  a  clearance  size  for 
the  next  round  figure  size. 
Then  the  cabinet  does  the  sorting,  all  balls  being  put  into  the  top 
drawer.  The  next  smaller  size  is  retained  in  the  second  drawer,  the 
third  size  in  the  next,  and  so  on.  When  using  balls  out  of  these 
drawers,  the  micrometer  should  be  used  to  determine  their  exact  size. 
Handy  Spring  Tool.  In  the  Ford  transmission-band  assembly 
there  are  three  springs  which  it  is  difficult  to  assemble  because  of 
the  trouble  in  holding  so  many  things  at  once.  To  eliminate  this 
trouble,  the  tool,  shown 
in  Fig.  302,  made  from 
flat  bar  stock,  can  be 
constructed.  The  han- 
dles, if  they  could  be 
called  that,  are  pivoted 
together  and  carry  a  kind 
of  fiat  jaw  with    three 

,  ,  Fig.  303.     Huidy  Sprinc  Too]  lor  Ford  Anembly 

notches  at    one  end. 

When  the  two  of  these  are  squeezed  tt^ther  by  means  of  the  screw 
and  handle  at  the  other  end,  the  flat  plates  will  hold  the  three  spring 
tightly  enough  so  that  all  can  be  inserted  in  tWit  ^^^^1  ^msv'wsKi 


GASOLINE  AUTOMOBILES 

at  oiu-e  by  iisiiit;  txit  one  hand.  Tools  of  this  kind,  which  save 
a  jjreat  lieal  of  tlie  workman's  time  and  thus  save  both  time  and 
money  for  the  owner  <•(  the  car,  should,  and  in  fact  do,  distinguish 
the  well-c<|iiii>ptit  rejiair  shop  and  garage  from  the  old-fashioned 
kind  which  is  iti  tlic  Imsiness  only  for  the  money  and  not  too  par- 
ticuliir  how  it  is  Kotten. 

In  transmissions  of  tl;e  planetary  tj^pe,  there  is  little  or  no 
trouble  except  witli  the  bands.  If  these  are  loose,  the  gears  will 
not  enfiiific  ami  the  desired  speed  will  not  result.  If  they  become 
soaked  with  {;re;i-,r,  oil,  or  water,  they  will  not  work  as  well  as  if  kept 
■  of  exressivc  grease,  will  slip  continually.  If 
IK'S  worn,  it  should  be  treated  just  as  a  brake 
ccteii  for  wear  and  found  not  badly  worn  but 
leaned  in  gasoline  and  then  in  kerosene,  after 
w,  or  coarse  file  may  be  used  to  roughen  it. 
mis  can  be  fixed  temporarily — sa\',  enough  to 
where  tools,  materials,  and  facilities  for  doing 
('  by  sprinkling  them  with  powdered  rosin  or 
inner  should  be  used  sparingly  because  it  will 
■  I  )(■  fjruh  hold  when  forcibly  applied,  and  at  timeii 


clean  t 
the  ba 

D'l 

i.l 

in  t 
iiiiut; 

1>c<'ort 

iiniiij; 

-. 

Whe 

1  insp 

slipper\, 

t  ma. 

he  c 

which 

1 

aw,  1 

acksax 

Son  let 

m 

-  «ri'i 

s\-  hii! 

^et  till 

r  to  i 

„l„..o 

the  w, 

rk 

ire  a 

ailal.l 

riiilcrV 

r: 

■til. 

I'll,-  t. 

GASOLINE  AUTOMOBILES 


419 


off  nicely  and  are  well  hardened  at  these  points — a  cutting  action 
which  gradually  wears  u  high  hurr  in  one  or  both  gears  is  liable  to 
be  set  up.  When  the  two  are  in  mesh,  the  burrs  are  on  opposite 
sides  and  contact  with  the  meshing  gear.  This  contact  will  make 
a  continuous  noise.  Its  remedy  is  the  removal  of  the  gear,  the 
filing  off  of  all  raised  portions,  the  filing  or  grinding  out  of  all  low 
spots  cut  into  the  teeth,  and  subsequent  hardening  to  make  repetition 
impossible. 

If  the  gears  have  worn  at  the  center  hole  where  they  slide  on 
the  shaft,  either  in  the  round  hole  or  at  the  kej'way,  this  must  be 
fixed  at  once.     In  the  former  instance,  the  gear  can  be  bushed,  and 


I^g.  303.    TmumiHion  Traubin  Illiulnled 

the  bushing  bored  out  to  fit  the  shaft,  while  in  the  latter,  a  slightly 
larger  key  may  be  fitted  into  the  shaft  and  the  ke\'way  may  be  recut 
to  accommodate  it.  Where  the  keys  liave  been  let  into  the  shaft, 
they  may  become  worn  in  one  spot  or  at  the  ends.  If  the  wear  is  all  in 
the  key,  it  can  be  replaced  with  another  of  the  same  size  made  slightly 
harder  in  the  process. 

If  the  main  bearings  are  of  the  roller  type,  the  wear  may  be 
taken  up  by  readjusting  the  position  of  the  roller  on  the  cone,  but 
if  they  are  of  ball  or  plain  bushing  form,  replacement  is  almost 
the  only  remedy,  unless  it  happens  that  in  the  case  of  a  plain  bush  the 
bush  is  split,  so  that  something  may  be  filed  off  of  the  t«o  cntiXja.'iCwv.^ 
sides,  and  the  holes  trued  out  to  this  new  size.    \u  V\\a.\,  iia.'sft,  ^I^^' 


430  GAf^OLINE  AUTOMOBILES 

advice  previously  given  under  the  subject  of  Plain  Engine  Bearings 
will  be  applicable. 

Play  in  the  shifting  rods  may  be  traced  to  one  of  two  things: 
looseness  at  the  connection  of  two  rods  or  of  a  rod  and  a  lever;  or 
looseness  in  the  bearings.  The  former  inevitably  requires  a  new  and 
slightly  larger  pin  driven  into  the  place  occupied  by  the  previous 
member.  Loose  bushings  will  mean  new  ones  if  the  trouble  is  serious, 
for  this  form  is  almost  always  of  the  solid  and  non-adjustable  ty[>p. 
In  many  cases  where  wear  occurs  on  a  solid  plain  hearing  Used  un 
the  end  of  a  plain  round  shaft,  if  peening  cannot  be  resorted  to. 
the  shaft  may  be  turned  down  a  very  little  bit,  say  ^  inch,  tlie  bushing 
turned  out  an  equal  amount,  and  a  thin  sleeve  bushing  made  of  this 
thickness  all  around  and  forced  into  the  pre\noas  member.  This 
saves  reboring  the  case,  which  is  an  expensive  and  difiicult  job, 
while  both  the  shaft  and  bushing  jobs  are  simple  ones. 

If  a  serious  defect  develops  in  the  case,  it  may  be  deanod  out 
and  welded.  This  is  not  a  job  for  the  amateur,  but  the  closing  of  a 
simple  crack,  no  matter  how  long,  would  be  an  easy  proposition  for 
the  owner  of  a  welding  outfit;  moreover,  it  would  be  a  very  short 
quick  job.  Autogenous  welding  should  always  be  resorted  tu  as  soon 
as  a  crack  tir  break  is  detected,  for  this  mav  save  the  exDen.te  and 


GASOLINE  AUTOMOBILES  421 

Adjusting  Annular  Bearings.  Makers  recommend  that  the 
irnier  race  be  pinched  so  tight  that  movement  is  impossible;  the 
outer  race  is  sometimes  allowed  a  little  freedom — .002  to  .003  inch. 

GEARS 

Since  the  whole  subject  of  transmission  concerns  itself  witH 
gears,  it  will  not  be  out  of  place  to  discuss  the  gears  themselves 
and  describe  the  many  different  kinds  in  use.  Speaking  broadly, 
the  gears  used  may  be  classified  according  to  the  position  of  their 
axes,  relative  to  one  another.  Thus  we  have  axes  parallel  and  in  the 
same  plane;  parallel  but  not  in  the  same  plane;  at  right  angles  and  in 
the  same  plane;  at  right  angles  and  not  in  the  same  plane;  at  some 
other  angle  than  a  straight  or  a  right  angle  and  in  the  same  plane; 
and  the  same,  but  not  in  one  plane.  These  classes  give  us  the  forms 
of  gear  in  common  use,  viz,  spur  gears,  bevel  gears,  helical  gears, 
herringbone  gears,  spiral  gears,  and  worm  gears. 

TYPES  OF  QEAR-CUTTINQ  MACHINES 

Before  discussing  these  various  kinds  of  gears,  it  may  be  wise  to 
familiarize  the  reader  with  the  special  features  of  different  types  of 
gear-cutting  machines.  Formerly,  the  teeth  were  cut,  one  gear  at 
a  time,  in  the  milling  machine,  this  being  practically  a  hand  opera- 
tion, since  all  movements  of  the  gear  or  cutter  had  to  be  made  by 
hand.  Later,  improvements  made  it  possible  to  cut  more  than  one 
gear  at  a  time,  which  resulted  in  lowering  the  cost,  but  did  not 
eliminate  the  hand  work. 

Step  by  step  special  machinery  was  developed  for  this  work, 
until  finally  a  perfected  machine  was  brought  out  which  did  all  the 
work.  With  this  machine,  the  workman  placed  the  cutter  on 
the  machine  spindle,  set  the  gear  blanks  into  position,  and  started  the 
machine,  after  which  it  went  on  automatically,  cutting  tooth  after 
tooth  to  a  correct  shape,  until  the  gear  was  finished,  when  it  was 
again  necessary  for  the  workman  to  shut  it  off  and,  after  taking  out 
the  finished  gears,  put  in  a  fresh  supply  of  gear  blanks. 

Many  machines  have  been  devised  and  perfected  in  recent  years 
owing  to  the  demands  of  the  automobile  manufacturers.  By  having 
a  battery  of  gear-cutting  machines  handled  by  a  single  man,  the 
cost  of  gear  cutting  has  been  brought  down  to  the  absolute  limit 
in  addition  to  a  decided  gain  in  gear  accuracy. 


GASOLINE  ArTOilOBILKS 


Whiton  Qear-Cutting  Machine.  The  Whiton  automatic  geaN 
cutting  machine  is  shown  in  Fig.  3(M,  The  cutttT  is  carried  by 
the  spindle  A,  which  is  juurnaled  in  a  saddle  B  sliding  upon  the 
swinging  carriage  C,  and  is  cupablc  of  adjustment  at  any  angle  neces- 
sary to  cut  bevel  gears.  The  machine,  as  shown,  is  arranged  for 
cutting  spur  gears.     The  cutter  ardor  .1  is  driven  by  the  pulley  }l  ill 


GASOLINE  AUTOMOBILES 


423 


Brown  and  Sharpe  Qear-Cutting  Machine.  Fig.  305  repre- 
sents a  Brown  and  Sharpe  gear-cutting  machine.  The  gear  blaiik  is 
carried  on  an  arbor  fitted  to  the  horizontal  spindle  A  and  supporte<l 
by  the  outer  supporting  bracket  B.  The  indexing  mechanism  is  in 
tlie  rear  of  the  indexing  wheel  C.  The  cutter  is  carried  by  the  cutter 
s|>in<lle  D  mounted  in  the  traveling  carriage  E.  In  smaller  machines 
the  base  upon  which  this  carriage  slides  is  pivoted  so  as  to  be 


set  at  any  required  angle  for  cutting  bevel  gears.  The  machine  is 
entirely  automatic  in  its  action.  It  has  an  attachment  for  cutting 
internal  gears. 

Automatic  Qear-Cutting  Machine.  The  automatic  gear-cutting 
machine  built  by  Gould  and  Eberhardt  is  shown  in  Fig.  306.  It  is 
of  the  same  type  as  that  built  by  Brown  and  Sharpe  and  possesses 
acme  excellent  features.    The  gear  blank  and  cutter  are  mounted  in 


42%  GASOLINE  AUTOMOBILES 

a  similar  mannrr.  and  the  adjustments  are  made  at  much  the  same 
points.  It  is  furnished  with  attachments  for  hobbing  worm  gears 
and  for  cutting  racks  and  internal  gears.  The  one  shown  13  not 
adapted  for  cnttiiig  bevel  gears. 

Becker  Gear-Cutting  Machine.  The  Becker  Milling  Machine 
Company  gear-cutting  machine,  Fig,  307,  is  of  the  milling-machine 
type,  It  WHS  designed  by  Amos  H.  Brainard,  a  builder  of  milling 
machines.    The  gear  blank  is  mounted  upon  an  arbor  fitting  a  taper 


GASOLINE  AUTOMOBILES  425 

the  change  gears  at  C.  These  are  driven  from  the  cone  pulley  D  by 
means  of  the  vertical  shaft  E  with  a  very  gradual  but  continuous 
motion  as  the  vertically  reciprocating  cutter  F  forms  the  teeth  on 
the  blank,  gradually  rotating  in  unison  with  the  rotation  of  the  blank. 
The  Teciprocating  movement  of  the  ram  carrying  the  cutter  is  pro- 
duced by  suitable  mechanism  within  the  casing  H  operated  by  the 
shaft  G.    The  machine  is  automatic  in  its  action  and  cuts  spur  gears 


Cairtttg  bI  Btcker  Milling  Uaehnu  Company.  Hydi  Parle,  AfoiHckiucUi 


and  internal  gears.     A  modified  form  of  machine  is  adapted  to  cutting 
the  teeth  of  racks.    The  cutting  action  is  that  of  planing. 

Qleason  Gear  Planer.  The  Gleason  gear  planer  is  shown  in 
Fig.  309.  It  is  an  excellently  designed  machine  with  a  single  tool 
having  a  narrow  rounded  cutting  point  for  planing  gear  teeth.  The 
gear  blank  A  is  mounted  on  a  horizontal  spindle  having  at  its  rear 
end  a  suitable  automatic  indexing  mechanism  B.  The  tool  C  is 
carried  in  a  redprocating  too!  block  D  which  traveb  upon  a  swing- 


GASOLINE  AUTOMOBILES 


ing  carriage  pivoted  at  E  directly  under  the  apex  of  the  base  cone  of 
the  gear  blank.  Tlie  exact  curve  and  direction  of  its  feed  are  con- 
trolled by  one  of  the  formers,  mounted  upon  tlie  triangular  former 
carrier,  which  may  be  rotated  so  as  tu  bring  either  former  tip  to  its 
operative  position,  making  a  rest  and  guide  on  the  outer  end  of  the 
swinging  carriage  for  the  friction  roller  K.    Of  the  three  former*,  nw 


GASOLINE  AUTOMOBILES  427 

Bllgram    Qear-Planing    Machine.    The   Bilgram   gear-planiag 
machine,  shown  in  Fig.  310,  operates  upon  a  principle  similar  to  that 


ESr-PUiniac  Michioe 


of  the  rnechine  just  described,  but  with  this  important  difference. 
In  the  Gleason  matihine,  the  tool  moves  so  as  to  trace  the  exact 
contour  of  the  side  of  the  gear  tooth,  in  addition  to  its  reciprocating 


428  GASOLINE   AUTOMOBlCES 

movement  for  cutting.  In  the  Bilgram  machine,  on  the  other  hand,  , 
the  tool  has  only  a  refijirocating  motion,  while  the  gear  blank  and  ' 
its  siipporticig  median iaiii  are  given  the  roiling  motion  similar  to  that 
imparted  by  one  rotating  gear  to  another,  which  is  that  of  a  rolling 
cone.  To  accomplish  this  motion,  the  axis  must,  in  the  first  place,  be 
moverl  in  the  manner  of  a  conical  pendulum;  therefore,  the  bearing  i 
of  the  arbor  which  carries  the  blank  is  secured  in  an  inclined  position 
between  two  uprights  to  a  semicircular  horizontal  plate,  which  can  be 
nseillated  on  a  vertical  axis  passing  through  the  apex  of  the  base  cone 
of  the  blank.  To  complete  the  rolling  action,  the  arbor  must,  in  the 
second  place,  receive  simultaneously  the  proper  rotation;  this  effect 
is  produced  in  the  machine  by  having  a  portion  of  a  cone  (correspond- 
ing with  the  pitch  cone  of  the  blank),  attached  to  the  arbor  and  held 
by  two  flexible  steel  bands  stretched  in  opposite  directions,  one  end 
being  attached  to  the  cone  and  the  other  to  a  fixal  part  of  the  mech- 
anism, thus  preventing  this  cone  from  making  any  but  a  rolling  motion 
when  tlie  arbor  receives  the  conical  swinging  motion.  In  the  engrav- 
ing, .  I  is  tlie  blank  to  be  cut,  ii  the  ram  carrying  the  cutting  tool,  and 
C  the  indexing  and  rolling  mechanism. 


GAfeOLJNE  AUTOMOBILES  429 

in  Fig,  31 1 .  This  is  the  final  drive  and  reduction  gear  of  the  Autocar 
commercial  cars,  made  by  the  Autocar  Company,  Ardmore,  Penn- 
sylvania. In  this  gear,  it  will  be  noticed  that  the  drive  from  the  engine 
is  through  bevels  to  an  intermediate  shaft  and  that  the  final  drive 
is  by  spur  gears. 

Helical  and  Herringbone  Gears.  In  situations  where  quiet 
running  is  deemed  necessary,  the  use  of  a  helical  gear  frequently  finds 
favor,  since  it  accomplishes  the  desired  result,  although  the  cost  of 


ComUnattoD  ol  Gem  in  the  Autoar  Final  Drira 


cutting  is  high.  Of  late,  these  gears  have  come  into  general  use  for 
camshaft  drives  and  similar  places.  A  pair  of  helical  gears  set  so  that 
the  helices  run  in  opposite  directions  forms  a  herringbone  gear. 
This  is  even  more  quiet  in  its  action  than  the  single  helix  and  pos- 
sesses other  virtues  as  well.  One  well-known  firm  has  adopted  it  for 
camshaft  driving  gears  and  makes  it  as  described  to  save  cutting- 
cost,  as  the  cost  of  cutting  a  true  herringbone  would  be  prohibitive. 
So  a  pair  of  helical  gears  of  opposite  direction  are  set  back  to  back  and 
riveted  or  otherwise  fastened  together,  forming  a  herringbone  gear  at 
a  low  cost.    Both  of  these  may  be  used  when  the  two  ab&fts  &.'e%  ^t- 


4S&-  GASOLINE  AUTOMOBILES 

allel  and  in  the  same  plane,  but  for  all  cases  where  the  shafts  are 
neither  in  the  same  plane  nor  parallel,  some  form  of  spiral  gear  must 
be  niaile  use  tif. 

Spiral  Gears.  Spiral  gears,  as  such,  are  not  generally  under- 
stiiiid,  but  that  variety  of  the  spiral  known  as  the  worm  gear  is 
very  simple  and  easily  understood  and  it  has  attained  much  popu- 
larity within  the  past  few  years.  This  popularity  has  been  due,  in 
part,  to  su[)erior  facilities  for  cutting  correct  worms  and  gears,  but,  in 
the  main,  to  a  superior  knowledge  of  the  principles  upon  which  the 
worm  works  and  uf  the  things  which  spelled  failure  or  success.  Thus, 
one  of  the  earliest  experimenters  in  this  line  laid  down  the  law  that  the 
rubbing  velocity  should  not  exceed  300  feet  per  minute  if  success  was 
desired  or  in  rotary  speed  about  80  to  100  revolutions.  For  auto- 
mobile use,  this  was  out  of  the  question;  but  later  experimenters 
found  that  these  results  only  attached  to  the  forms  of  gear  usetl  by 
the  early  workers  and  did  not  apply  to  a  strictly  modem  gear  laid 
down  on  scientific  principles. 

The  mistake  made  was  in  the  pitch  angle  of  the  worm,  which 
was  fornifrly  made  small,  nothing  over  15  degrees  being  attempted. 
This  wiL.s  tiie  item  tliat  was  at  fault  and  that  caused  this  very  useful 

eHicicnt  nirxlL-  of  ilriving  to  fall  into  disuse.     As  soon  as  this 


GASOLINE  AUTOMOBILES 


431 


Woods  electrics;  Pierce,  Packard,  Riker,  Mack,  Atterbury,  Blair, 
Chase,  Gramm,  G.M.C.,  Hulburt,  Moreland,  Standard,  Sterling,  and 
other  trucks;  Dennis  (English)  busses  and  trucks  and  Greenwood  and 
Batley  (English)  trucks. 


nr  af  Timkra-DttToii  A 


Spiral  Bevels.    The  spiral  bevel  is  a  new  development,  having 
been  brought  out  in  1914  as  a  compromise  between  the  worm  and  the 


straight  bevel.    As  such,  it  is  supposed  to  have  pratticaliy  all  the 
advantages  of  both,  except  that  it  does  not  afford  the  great  speed 


>    I; 


GASOLINE  AUTOMOBILES  433 

where  it  will  be  noted  that  the  worm^ear  housing  in  the  center 
is  actually  higher  than  are  the  brake  drums  at  either  end  of  the  axle. 
This,  too,  despite  the  fact  that  a  truss  rod  passes  beneath  the 
center  of  the  axle.  For  heavy  trucks,  especially,  and  for  electric  pleas- 
ure cars,  the  worm  has  proved  an  ideal  drive.  In  these  situations, 
there  is  the  condition  of  high-engine  or  electric-motor  speed,  coupled 
with  low-vehicle  speed  requirements,  which  necessitate  a  considerable 
reduction.     As  pointed  out,  the  worm  gives  this  in  a  small  space. 

For  1916,  the  very  apparent  tendency  in  final  drives  is  toward 
spiral  bevels  for  pleasure  cars  and  worms  for  electrics  and  trucks. 
The  tendency  toward  spirals  is  very  great,  amounting  practically 
to  a  landslide,  57  per  cent  using  it  against  10  for  1915.  The  devel- 
opment of  special  machinery  for  cutting  these  gears  and  the  under- 
standing of  their  use  has  brought  this  about.  In  the  truck  field 
there  has  been  a  similar  movement  toward  the  worm,  due  to  similar 
causes. 

Gear  Pitch  and  Faces.  The  manufacturers  of  transmissions  and 
of  gears  for  them  do  not  agree  as  to  the  best  gears.  Neither  do  they 
agree  as  to  which  gears  are  most  quiet  or  most  efficient.  In  general, 
coarse-pitch  stub-tooth  gears  are  gaining  faster  than  any  other  form. 
The  6-8  pitch  is  fairly  general  for  gears  of  j-inch  and  J-inch  face, 
and  4-5  pitch  for  wider  gears.  One  manufacturer,  Warner,  con- 
siders the  finer  pitch  gears  and  narrower  faces  as  less  likely  to  make 
noise,  since  they  will  not  distort  as  much  in  hardening  as  wider  gears. 
In  this,  other  manufacturers  agree,  but  there  are  some  who  claim  to 
have  had  both  quiet  and  noisy  operation  with  both  fine  and  coarse 
pitch.  The  tendency  toward  compactness  has  not  increased 
transmission-gear  faces  any  appreciable  amount,  nor  has  the 
increased  use  of  better  steels  and  better  hardening  processes  lessened 
the  size  of  tJie  four  noticeably.     , 

Gear  Troubles.  Most  of  the  common  gear  troubles  have  been 
previously  covered  at  the  end  of  transmissions.  There  is  not  as 
much  trouble  with  gears  today  as  there  was  several  years  ago.  This 
is  due  to  better  design,  better  materials,  better  processes,  and  better 
assembling  on  the  part  of  manufacturers  and  to  more  skill  in  handling, 
caring  for,  and  adjusting  on  the  part  of  owners.  Of  course,  the 
repair  man  still  finds  plenty  to  do,  but  the  percentage  of  gear  repairs 
is  relatively  less  than  ever  before. 


-4j4  GAt^OLINE  AUTOMOBILES 

SUMMARY  OF  INSTRUCTIONS 

CLUTCHES 

Q.     Why  is  a  clutch  needed? 

A.  Tilt'  chilcli  is  needed  to  disconnect  the  rest  of  the  drive 
friiin  the  engLne.  The  jjasoline  engine  cannot  start  under  a  load  but 
must  first  (jet  up  speed.  By  means  of  tlie  clutch,  which  can  be 
thrown  oLit,  the  eTipiiie  is  allowed  to  run  alone  and  get  up  the  nei'es- 
sary  speed,  then  the  \tmi\  or  drive  can  be  thrown  on.  This  is  just  as 
true  of  the  stjitiiULary  gas  engine  as  of  the  automobile,  motor  boat, 
or  aeniplane  power  plant. 

Q.    How  does  the  clutch  act? 

A.  It  is  designed  and  constructed  so  that  the  amount  of  frictinn 
surface,  with  the  spring  pressure  provided,  is  sufficient  to  transmit 
the  whole  power  of  the  engine  (and  slightly  more  as  a  factor  of 
safety)  when  the  clutch  is  in.  In  addition,  it  is  so  designed  and  cfin- 
strueted  that  when  the  clutch  is  out  the  spring  pressure  is  taken  up 
in  such  a  way  us  tn  he  self-contained,  that  is,  its  thrust  is  carried  tu 
a  member  milsiiic  of  the  clutch  itself  which  is  able  to  withstand  this 
thrust.     Ill  this  way.  when  the  clutch  is  out,  the  engine  is  entirely 


GASOLINE  AUTOMOBILES  435 

Q.    What  are  the  two  divisions  of  the  cone  form? 

A.  The  cone  form  is  made  in  two  ways,  the  direct  form  and 
the  indirect  form.  The  direct  form  has  the  cone  introduced  directly 
into  the  flywheel,  which  is  tapered  inwards  for  this  purpose.  This 
makes  it  a  very  simple  device  to  construct,  the  machining  of  the  fly- 
wheel forming  the  female  portion  of  the  clutching  surface.  The  indi- 
rect form,  or  inverted  cone,  differs  in  that  the  female  portion  is  made 
as  a  separate  flange  bolted  to  the  fl>nvheel  and  tapering  outward. 
The  cone  is  placed  inside  of  this,  so  that  it  works  out  against  the 
clutching  surface  instead  of  in  against  this  surface,  as  in  the  direct  type. 

Q.    What  are  the  relative  advantages  of  the  two  forms? 

A.  The  indirect  is  little  used  now,  although  it  was  popular  years 
ago.  The  extra  bolted-on  inverted  cone  adds  to  the  fl>nvheel  weight, 
for  it  is  large  and  heavy  and  gives  considerable  flywheel  effect.  How- 
ever, the  fl^nvheel  is  simplified.  The  spring  is  enclosed  between  the 
fl^'wheel  and  the  cone,  this  being  considered  an  advantage  in  the  early 
days  but  now  considered  a  disadvantage  because  it  is  inaccessible  for 
inspection  or  adjustment.  The  cone  is  pushed  in — away  from  the 
clutching  surface — to  disconnect  it,  while  on  the  more  simple  direct 
t\T>e,  the  cone  is  pushed  out — away  from  the  clutching  surface — to 
disconnect. 

Q«    What  are  the  divisions  of  the  disc  clutch? 

A.  Disc  clutches  are  generally  grouped  according  to  lubrication, 
those  which  run  in  oil  being  called  wet,  and  those  which  run  without 
lubricant  of  any  kind  being  called  dry.  In  addition,  a  distinction  is 
generally  made  between  the  disc  clutch  with  a  very  few  plates  (one, 
two,  or  three),  usually  called  a  plate  clutch,  and  the  form  with  many 
plates  (10  or  more)  which  is  called  a  multiple-disc  clutch.  Either 
plate  or  multiple  form  may  run  wet  or  dry. 

Q«  Explain  the  difference  between  the  wet  and  dry  multiple 
forms. 

A.  In  the  wet  form,  the  plates,  or  discs,  are  plain  steel  and  are 
submerged  in  oil,  the  entire  clutch  housing  being  filled  with  oil.  The 
clutch  discs  work  steel  face  against  steel  face,  the  action  of  the  spring 
when  the  clutch  is  let  in  gradually  squeezing  out  the  oil  from  between 
the  faces.  This  gradual  squeezing  out  of  the  oil  gives  this  form  its 
gradual-application  quality,  for  with  aiix  or  seven  pairs  of  discs  the 
squeezing-out  process  takes  an  appreciable  length  of  time.    Iw.  IVnr 


436  GASOLINE  AUTOMOBILES 

dry  fonii,  the  plates  are  iirdmariiy  faced  with  a  special  clutching 
surface  of  woven  asbestos  fabric  similar  to  brake  lining,  this  being 
placed  upun  every  alternate  disc,  that  is,  the  actual  clutching  surfaces 
consist  of  steel  and  fabric  alternating.  The  general  method  of  con- 
struction is  to  take  one  set,  say  the  inner  discs,  and  face  both  sides  of 
each  one.  Then  none  of  the  outer  discs  are  faced,  so  that  when  the 
clutch  is  assembled  there  is  a  steel  face  against  each  fabric  face.  This 
form  is  run  absolutely  dry;  in  fact,  considerable  pains  is  taken  in 
design  and  assembly  to  keep  out  any  form  of  lubricant. 

Q.  Explain  the  difference  between  the  plate  and  the  multiple- 
disc  forms. 

A.  In  the  niultiple-tlisc  form,  a  considerable  number,  say  II,  13, 
15,  or  some  such  number  of  discs,  is  used;  the  smaller  number,  as  5, 
6,  7,  etc.,  being  the  drivinj!;,  and  the  larger  half,  as  8,  9,  10,  etc.,  being 
the  driven.  In  the  plate  form,  a  very  small  number  of  plates  of  the 
largest  size  which  the  flywheel  will  allow  is  used.  As  a  rule,  the  fly- 
wheel inner  surface  is  machined  out  to  form  one  of  the  surfaces,  the 
engaging  or  disengaging  member  another,  and  a  single  disc  between; 
or,  perhaps,  another  l.ir^e  disc  is  fixed  to  the  flj-wheel  and  two  discs 
used  between  tliis  and  the  other  two  surfaces.     The  plate  form  has  the 


GASOLINE  AUTOMOBILES  437 

ably  called  for  complete  enclosure,  making  adjustments  and  replace- 
ments difficult.  The  smaller  springs  are  usually  placed  outside, 
so  that  they  can  be  adjusted  or  replaced  easily  and  quickly.  It  has 
been  found,  too,  that  by  using  a  large  number,  say  6,  7,  or  more, 
distributed  around  the  clutching  surface,  a  much  lighter  spring  pres- 
sure can  be  used  with  equally  good  effect.  In  fact,  many  modern  cars 
have  so  light  a  clutch  spring  that  it  can  be  disengaged  with  one  finger. 

Q.    How  does  the  contracting-band  clutch  work? 

A.  It  has  two  half-bands  which  the  clutching  mechanism  draws 
tight  against  a  drum.  In  effect,  a  contracting-band  clutch  is  like  a 
band  brake,  except  that  the  braking  band  is  in  two  halves  and  operates 
from  the  center  instead  of  from  the  exterior  surface. 

Q.    Is  this  a  popular  form? 

A.  No.  It  is  rapidly  going  out  of  use;  only  one  or  two  American 
cars,  with  perhaps  the  same  number  in  Europe,  are  now  using  it. 

Q.    How  does  the  expanding-band  clutch  work? 

A.  In  a  somewhat  similar  manner  to  the  expanding,  or  internal, 
brake;  that  is,  it  has  two  segments  of  fairly  stiff  metal  section,  which 
the  movement  of  a  cam,  or  expander,  presses  outward  against  the 
inside  of  the  clutch  drum  (or  inside  face  of  the  flywheel).  This  cam, 
or  expander,  is  worked  by  the  movement  of  the  clutch  pedal,  or  spring 
— outward  so  as  to  expand  the  band  and  take  hold  of  the  drum  for 
engagement;  inward  so  as  to  allow  the  band  to  contract. 

Q.    Is  this  type  gaining  in  popularity? 

A.  No.  On  the  contrary,  it  is  losing  so  rapidly  that  there  are 
practically  no  cars  built  in  this  country  with  it,  although  a  number 
of  old  cars  with  this  form  are  still  running. 

Q.    What  is  the  usual  position  of  the  clutch? 

A.  Within  the  flywheel.  This  saves  a  great  deal  of  space,  a 
number  of  parts,  and  considerable  weight. 

Q.    Why  is  this  position  used  so  freely? 

A.  Partly  because  of  the  savings  just  mentioned,  and  partly 
because  of  the  rapidly  growing  use  of  unit-power  plants  which  forces 
this  location.  With  the  engine  and  transmission  as  a  unit  and  the 
necessity  for  the  clutch  being  between  them,  the  fl>nvheel  interior  is 
about  the  only  place  for  the  clutch. 

Q.  How  can  the  surface,  and  thus  the  transmitting  power,  of 
clutch  discs  be  increased? 


438  GASOLINE  AUTOMOBILES 

A,  By  the  \ise  of  other  than  plane  snrfac'es.  Thus,  in  the  Helc- 
Sliiiw  fnrm  ejuh  disc  is  inatie  with  a  small  cone  projecting  from  il. 
The  outside  of  this  engages  with  the  interior  of  the  cone  on  the  next. 
Other  forms  have  half-cone  or  other  inclined  surfaces  and  half-plane 
surfaces.  As  a  Htraisht  line  is  the  shortest  distance  between  two 
points,  so  a  plane  flat  surface  gives  the  smallest  area  between  any  two 
points  in  parallel  surfaces.  From  this  it  is  apparent  that  any  surface 
not  plane  offers  a  greater  area  than  does  the  plane  one.  However, 
the  plane  surface  is  so  much  easier  and  cheaper  to  make,  use,  replace, 
etc.,  that  it  has  gradually  driven  out  all  these  forma  with  greater  sur- 
face despite  their  advantages  in  the  way  of  transmitting  power. 

Q.    What  causes  a  slipping  cone  clutch? 

A.  A  slipping  cone  clutch  is  generally  caused  by  oil,  grease,  or 
other  lubricant  on  the  clutching  surface  or  by  a  weak  spring. 

Q.    How  can  this  be  remedied? 

A.  The  snrfiue  can  be  cleanetl  with  kerosene,  then  with  gaso- 
line, and  dried.  Or,  if  the  surface  is  glazed,  it  can  be  roughened  by 
using  a  file.  Or,  if  the  slipping  occurs  out  on  the  niad  and  no  tools 
are  available,  any  powder  or  fine  material  which  will  give  roughness 
can  be  used.     It  is  possilile  to  get  home  with  a  slipping  cone  clutch 


GASOUXE  AUTOMOBILES  439 

2.  Tell  how  you  would  adjust  the  Steam^-Kniglit  dutch  sprioj^. 

3.  Give  the  method  of  removing  and  replacing  a  clutch  spring 
in  the  Warner  clutch. 

4.  If  springs  under  the  dutch  facing  of  a  cone  dutch  do  not 
produce  gradual  engagement,  what  is  the  matter,  and  how  would  you 
remedv  it? 

5.  How  does  the  Cadillac  dutch  work? 

6.  How  does  it  differ  from  other  dutches  of  the  same  type? 

7.  How  would  you  lubricate  a  dutch  bearing,  with  what,  awl 
how  often? 

8.  Describe  a  quick.  ea5>'  method  of  replacing  eorib  in  a  dutch. 

9.  How  would  you  ocAstruct  a  dcr\ioe  to  hold  dutdi  springs 
while  replacing  them? 

TttASSmSSiOSS 


Q.    l^lat  is  Ae  pwpofe  of  tlK 

A.  To  aDow  variatJoflDf  in  tLe  sp«iwl  of  the  car  fonraid  twm  tbe 
lowest  to  the  higlaesau  and  for  m'erw*.  without  var>iQg  the  OMAor 
speed  greatly. 

Q.    ^^ 
away  ^ 

A.  Tlie  knnet;!  f^iebd  uwfi  in  car&  ordinajily  would  xrA  be  po6^ 
sible  with  tbe  ppeeieiit  engine,  sinoe  it  «Muld  XKft  be  vaiuounA  down 
slow  cnoo^  AgaixL  if  the  gearing  were  sudi  a^  Vj  give  tbe  psmmA 
lowest  car  sptoeds  with  the  ^sD^cut  low  speed,  tbec  tor  nttrimwn  e^pne 
^leeds  tbe  hi^iiest  potsuhk:  car  Hpeed  would  be  ver^-  k*w.  In  abort. 
gei^ring  is  iieoesB;^^^'  to  give  a  greai^r  vanatioD  tbac  is  possible  with 
the  engiiie  alone.  Further,  reverw  could  not  be  obtained  without 
addjtirinal  gearE>  and  thi£>  would  ueoesaitate  alsc^  a  method  uf  ^uftipg 
the  revtTwt  gear  into,  and  out  of.  itie^.  Tliu:^.  all  Uie  requiftaneut^  of 
the  modern  gear  tranamission  would  be  neoeaaar>'  fur  revove  akioe. 

Q.    Sbam  Inlfer  aar  of  fipma  Ifer  m^uuMSt}  of 


A.  The  dnrumferenee  of  J^i-ioch  wlteels  is  1%.^  incsie&.  or  1 1 .4 
feet.  With  the  engine  geared  direct  u*  the  wboek.  the  speed  of  the 
latter  would  be  directly  proportional  to  tbe  former,  conf&idenng  the 
^ear  reduction.  If  an  average  preMmv-day  gear  reductioD  of  o.8  to  1 
be  cxnaidcnd  act  240  r.pjn..  which  it  ver>  low.  the  car  would  maLe 


■tm  GASOLINE  AUTOMOBILES 

10.3  m.p.h.  as  its  lowest  possible  speed.  And  at  240()  r.p.m, — a  higli 
maximuni  for  an  engine  with  as  low  a  speed  aa  240—the  highest  cur 
speed  would  be  103  m.p.h.  As  the  average  roads  would  not  allow  this 
high  a  speed,  and  as  the  average  car  has  a  low  speed  appro.\ioiatin^ 
3  m.p.h.,  it  is  apparent  that  the  gear  ratio  is  too  high.  By  lowerine 
this  to  12  to  1  at  a  low  speed  of  264  r.p.m.  of  the  engine,  a  low  mr 
speed  of  2.S5  m.p.h.  would  be  obtained.  And  with  2ti40  r.p.m.  as  the 
highest  engine  speed,  the  highest  car  speed  would  be  only  2S.5  m.p-h. 
From  these  two  extremes,  It  is  apparent  that  direct  gearing  without 
a  transmission  is  not  feasible. 

Q.    What  are  the  general  classes  of  transmission  now  in  use? 

A.  There  are  five  general  classes:  sliding  gear,  individual  chitcli. 
planetarj-,  frictimi,  and  miscellaneous  tj-pes.  The  first  named  is  most 
popular  and  con.'ititutes  perhaps  90  or  more  per  cent  of  all  the  cars 
now  built.  The  individual  clutch  is  really  a  modification  of  the  slid- 
ing gear,  but  is  not  .widely  used — not  to  exceed  3  or  4  per  cent.  The 
planetary  is  the  most  simple  form  to  operate  but,  unlike  the  others, 
is  hmited  as  to  the  number  of  possible  speeds.  Practically  the  only 
American  maker  using  this  today  is  Ford.  The  friction  form  was 
intended  to  give  a  maximum  number  of  speeds  with  maximtun  sata- 


GASOLINE  AUTOMOBILES  441 

A.  The  operator  is  at  liberty  to  select  any  gear  he  desires  and 
to  go  directly  to  that  speed  from  the  speed  which  he  is  using.  This 
means  with  common  sense  reservations;  for  instance,  it  would  be 
foolish  to  go  from  high  to  reverse,  although  this  is  possible  in  this 
form. 

Q.    How  is  this  accomplished? 

A.  Within  the  gear  box,  the  gears  are  shifted  by  forms,  and  the 
quadrant  arrangement  is  such  that  the  driver  can  shift  his  lever  so  as 
to  pick  up  the  fork  which  will  give  the  desired  speed.  Usually  there 
are  but  two  shifting  members  (in  the  three-speed  form),  one  giving 
low  speed  and  reverse,  the  other  intermediate  and  high.  Having 
picked  up  the  low  and  reverse  fork,  he  can  shift  his  lever  forward  for 
low  and  backward  for  reverse;  similarly,  with  the  other  fork  for 
second  and  third  speeds. 

Q.    How  does  the  progressive  form  work? 

A.  In  this  t>T>e  of  gear  box,  the  speeds  must  be  used  in  succes- 
sion— first  the  low,  then  second,  then  high,  and  when  slowing  down 
from  high,  to  second,  then  low,  then  reverse.  For  instance,  if  driving 
in  high  and  a  turn  is  passed  in  a  narrow  road,  it  would  be  necessary 
to  shift  down  to  second,  then  to  low,  then  to  reverse.  The  driver 
could  now  back  his  car  past  the  street  into  a  position  which  would 
enable  him  to  make  the  turn.  Then  he  could  speed  up  the  car  again 
by  using  first  low  speed,  then  second,  and  finally  high.  This  maneu- 
ver could  not  be  accomplished  in  any  other  way.  In  the  same  cir- 
cumstances with  a  selective  gear,  the  car  could  be  brought  to  a  dead 
stop  with  the  brakes,  an  immediate  shift  to  reverse  effected,  the  car 
backed  up,  and  the  gears  shifted  to  low  and  then  high  speed  forward, 
thus  doing  the  same  thing  as  before  with  half  as  many  changes. 

Q.    How  is  the  high  speed  generally  effected? 

A.  High  speed  in  all  modem  transmissions  is  a  direct  drive  so 
that  none  of  the  various  gear  reductions  are  in  use.  This  method 
reduces  the  amount  of  noise  by  eliminating  at  once  the  meshing  of 
two  sets  of  gears,  the  average  high-speed  direct  drive  being  effected 
by  clutching  one  gear  up  to  another. 

Q.    Is  this  arraiq;ement  always  used? 

A.  No.  In  some  four-speed  gears  the  highest  speed  is  a  geared- 
up  form,  and  the  direct  drive  is  used  on  third  speed.  This  is  done  with 
the  idea  of  securing  the  silence  of  the  direct  drive  for  all  averafi^ 


4*2'  GASOLINE  AUTOMOBILES 

rapid  driving,  wliile  the  geared-up  form  gWcs  an  extraordinary  spee<i 
for  emergen  cies  where  imise  is  iniinateritii. 

Q.  In  the  electric  gear  shifter,  how  is  the  movement  of  gears 
effected? 

A.  The  shifter  is  ninde  with  a  series  of  electromagnets,  or  sole- 
noids, one  for  each  speed  and  one  for  reverse.  Current  flows  to  these 
when  the  proper  biittun  is  pressed.  It  is  well  known  that  when  an 
electric  current  is  passed  through  an  electromagnet  of  the  solenoid 
type,  the  rod,  or  bar,  inside  of  it  is  drawn  forward.  This  arrangement 
produces  the  speed  corresponding  to  the  button  pressed.  In  actual 
practice,  the  current  docs  not  flow  until  the  clutch  pedal  is  depressed 
after  the  button  iuis  bwn  pressed. 

Q.    Where  is  the  transmission  located? 

A.  Excluding  freak  forms,  there  are  four  general  positions:  in 
unit  with  the  motor;  amidships  in  unit  with  the  clutch;  amidships 
but  separated  from  the  clutch  and  in  unit  with  the  forward  end  of  tlie 
tiriviug  shaft;  ami  in  unit  with  the  rear  axle. 

Q.    Are  these  same  locations  used  on  motor  trucks? 

A.  Yes.  Except  tliat  the  third  class  is  sometimes  modified  with 
chain  i!ri\e.  sn  ihat  the  transmission  is  amidships  but  in  unit  with 


GASOLINE  AUTOMOBILES  443 

a  gear  on  s  shaft  to  which  it  is  keyed,  moves  a  clutch  which  keys  the 
desired  gear  to  the  shaft. 

Q.    What  is  the  advantage  of  this  over  sliding  gears? 

A.  In  the  sliding  gear,  the  moving  members  must  take  the  drive 
and  transmit  the  power  in  addition  to  withstanding  the-shocks  and 
destructive  action  of  shifting  or  meshing.  In  the  individual  clutch 
form,  the  gears  have  only  to  transmit  the  power,  whjle  the  individual 
clutches  have  ojtiy  the  shocks  and  destructive  action  of  shifting. 

Q.    How  are  gears  pressed  onto  their  shafts? 

A.  Usually  by  means  of  a  hydraulic  or  a  power  press — one 
capable  of  exerting  a  pressure  of  many  tons.  Generally,  it  is  easier 
to  lay  the  gear  out  on  the  press  table  and  press  the  shaft  down  into 
it,  than  the  reverse. 

Q.    How  are  pressed-on  gears  removed? 

A.  The  process  of  pressing  on  is  reversed,  and  the  gear  is  sup- 
ported in  such  a  way  that  the  shaft  can  be  pressed,  or  forced,  out  of  it. 

Q.    How  is  the  transmission  removed  from  the  chassis? 

A.  The  usual  method  in  well-equipped  shops  is  to  put  a  rope 
or  chain  sling  or  special  cradle  around  the  transmission,  then  to  lift 
it  vertically  upwards  by  means  of  a  block  and  tackle,  electric  or  pneu- 
matic overhead  hoist,  chain  block  attached  to  overhead  tracks,  or 
portable  crane. 

Q.    How  are  bearings  worked  in? 

A.  After  slow  careful  fitting  by  hand  for  both  diameter  and 
length,  using  a  dummy  shaft  with  dummy  bearings,  the  real  bearings 
should  be  put  in  place  and  run-in  for  several  hours,  using  power  from 
a  line  shaft.  Transmission  bearings  should  be  run-in  the  same  as 
engine  bearings,  set  up  somewhat  tight  and  with  an  excess  of  oil. 
Questions  for  Home  Study 

1.  Describe  the  construction  of  the  Cadillac  and  Winton  trans- 
missions, a  railway  transmission,  the  Mack  truck,  the  Ford  planetary, 
a  friction  form,  and  a  magnetic  type. 

2.  How  would  you  adjust  the  shafts  longitudinally  in  the 
Steams  transmission? 

3.  Tell  how  to  construct  a  stand  for  gear  pressing. 

4.  Give  a  thorough  method  of  cleaning  a  transmission. 

5.  What  are  the  usual  gear  pitches? 

6.  What  is  meant  by  the  pitch  of  a  gear? 


GASOLINE  AUTOMOBILES 

PART  V 


STEERING   GROUP 

The  mechanisms  by  which  steering  is  effected  are  among  the 
most  important  features  of  a  car,  if  not  actually  the  most  important. 
The  truth  of  this  statement  will  be  realized  when  attention  is  called 
to  the  fact  that  safe  steering  is  the  final  requisite  that  has  made  the 
modern  high  speeds  possible,  t6f  without  safe  and  dej)endable  steering 
gears,  no  racing  driver  would  dare  to  run  a  machine  at  a  high  rate  of 
speed,  knowing  that  at  any  minute  the  unsafe  steering  apparatus 
might  shift  the  control,  thus  allowing  the  front  wheels  to  waver  and 
the  car  to  run  into  some  obstruction  by  the  roadside. 

The  same  argument  applies  in  an  even  greater  degree  to  the 
case  of  the  non-professional  driver,  who  wants  to  be  on  the  safe  side 
even  more,  perhaps,  than  do  the  dare-devils  who  drive  racing  cars. 
Neariy  all  of  our  roads  are  curved  and,  to  make  all  of  these  turns 
with  safety,  the  steering  gear  must  be  reliable.  Again,  in  mountain- 
ous country  where  there  may  be  a  sheer  drop  at  the  roadside  of 
hundreds  of  feet,  it  becomes  necessary  that  the  steering  mechanism 
be  very  acciuute  aftd  that  it  obey,  at  once,  the  slightest  move 
on  the  driver's  part.  To  secure  this  accuracy,  there  must  be  no  lost 
motion  or  wear  of  the  interrelated  parts: 

These  things  mean  that  the  whole  steering  mechanism  must  be 
safe  and  reliable;  strong  and  acciurate;  well  made  and  carefully  fitted; 
well  cared  for;  and  finally,  the  design  and  construction  must  be 
based  on  a  theoretically  correct  principle,  for  otherwise  the  mechanical 
refinements  will  have  been  wasted.  Perhaps  it  will  be  more  logical 
to  treat  the  mechanical  requirements  first  by  showing  how  the 
present  tj^  has  been  evolved  from  the  failures  of  earlier  forms. 

STEERING  GEARS 

General  Requirements.  In  turning  a  comer  a  car  follows  a 
curve,  the  outer  wheeb  obviously  following  curves  of  longer  radius 
than  do  the  inner  wheeb  and,  therefore,  traveling  farther.    In 


440  GASOLINE   AUTOMOBILES 

straight-ahead  running,  the  wheels  run  parallel  at  all  times  and 
travel  the  same  distance.  These  two  faets  are  the  basic  ones  which 
make  the  steering  attitm  so  complicated:  First,  that  on  straight- 
ahead  running  the  wheels  must  travel  the  same  distance;  and  second, 
that  on  turninp  curves  the  outer  wheels,  whichever  they  may  be, 
must  travel  a  greater  distance. 

This  double  requirement  leads  to  the  usual  form  of  steering 
arrangement,  called  after  its  inventor,  the  "Ackerman".  It  was 
Ackerman  who  brought  out  the  first  vehicle  in  which  the  front 
wheels  were  mounted  u[xni  pivoted-axle  ends,  these  ends  being  pivoted 
on  tlie  extremities  of  the  central  part  of  a  fixed  axle,  while  the  pivoted 
ends  carried  nnc  lever  each.  These  levers  were  connected  together 
by  means  of  a  cross-rod,  while  at  one  end  another  rod  was  attached, 
which  was  used  to  move  the  wheels.  By  moving  this  latter  rod, 
Inith  wheels  were  compelled  to  turn  about  their  pivot  points,  since 
the  cross-rod  joined  them  together,  and  if  one  moved  the  other  had 
to  move  also.  Tliis  was  Ackerman's  substitute  for  the  fifth  wheel 
which  had  been  used  up  to  that  time  and  is  even  to<lay  on  all  horse- 
plicated 


GASOLINE   AUTOMOBILES 


447 


pivot,  which  is  liable  to  wear,  inaccessible,  it  also  was  ab&ndoDed. 
However,  later  tendencies  point  toward  a  revival  of  this  constnictioii. 
The  result  is  that  today  we  are  using  a  form  which,  though  far 
from  being  ideal,  fulfills  every  practical  requirement.  This  form  is 
usually  constructed  as  in  Fig.  316,  which  shows  a  skeleton  plan  view 
of  an  automobile.  In  this,  the  line  AB  represents  in  length,  posi- 
tion, and  direction,  the  front  axle  of  a  car,  while  ML  represents 
in  a  similar  manner  the  rear  axle.  A  and  B  also  are  the  pivot  points 
for  the  axle-stud  ends  or,  as  they  are  more  commonly  called,  the 


^....^.....^.,. 


Fif.  3ie.     Diacrun  of  Steering 


steering  knuckles  or  steering  pivots,  which  are  represented  by  the 
lines  AB  and  BC. 

The  rear  (or  front,  as  the  case  may  be)  ends  of  the  steering 
knuckles  are  joined  by  the  connecting  rod  DC  The  Ackerman  con- 
struction is  such  that  the  center  lines  of  the  steering  arms,  or  levers, 
AB  and  BC,  prolonged,  must  pass  through  the  center  point  of  the 
rear  axle  at  K;  the  reason  for  this  is  that  the  front  wheels  are  sup- 
posed to  turn  about  the  center  of  the  rear  axle  as  a  center. 

Action  of  Wheels  In  Turning.  If  the  wheels  are  supposed  to 
turn  through  an  angle,  the  action  of  the  above  arrangement  will  be 
seen.  Suppose  the  steering  gear  (not  shown  in  Fig.  316)  is  turned  so 
as  to  move  the  steering  lever  AB  to  the  new  position,  shown  dotted 
at  AI>\.  Thb  movement  will  also  move  the  other  lever  BC  to  a  new 
position,  shown  dotted  at  BC\.  It  will  be  noted  in  this  position  that 
the  angle  through  which  the  right-hand  lever  BQ  has  swung  ia  notAa 


44S  GASOLINE  AUTOiMOBILES 

great  as  that  through  which  the  left-hand  lever  AD  has  moved, 
although  the  twu  levcra  are  attached  together  by  means  of  the  cross- 
connection  DC. 

The  wlieels  arv  mounted  upon  the  extreniities  of  the  steering 
knuckles  at  /'  and  /;  EG  represents  the  left  wheel,  and  HJ  the 
right  wheel.  These  turn  about  the  pivot  points  A  and  B,  with 
the  movement  of  the  steering  knuckles  to  the  new  positions,  shown 
dotted  at  /si/'[G[and  lIiIiJi.  In  this  position,  prolongations 
of  the  lines  through  the  pivot  point  and  the  center  of  the  two 
wheels  will  meet  the  rear-axle  center  line  prolonged  at  separate 
points  as  01',  the  two  lines  converging  slightly.  This  same  con- 
vergence may  be  noted  by  prolonging  the  center  line  of  the  two 
wheels  EiGi  to  Q  and  IltJi  to  R.  This  divergence  means  that 
the  two  wheels  are  turning  on  curves  of  different  radii,  and  since  the 
outer  wheel  11  iJ  \  sliows  a  longer  distance  from  its  center  line  pro- 
longed to  the  rear-ax!e  line  0PM KL  than  does  the  inner  wheel, 
that  is,  has  the  longer  false  radius,  PIi  being  longer  than  Of  i,  it 
follows  that  the  turning  action  will  be  correct. 

This  is  siiniewhiit  complicated  and  rather  hard  to  follow,  but 
the  figure  secmH  simple  and  should  be  examined  closely,  even  draw- 


GASOLINE  AUTOMOBILES 


440 


known  as  the  Davis,  the  steering  levers  are  set  in  front,  but  taper 
inward  instead  of  outward,  so  that  their  center  lines  prolonged 
meet  the  center  line  of  the  car  prolonged  at  a  distance  from  the  front 
axle  equal  to  the  distance  between  the  front  and  rear  axles,  or  equal 
to  the  wheel  base. 

In  addition,  the  connecting  rod  is  carried  in  guides  placed  on 
the  front  of  the  axle,  so  that  its  path  of  travel  is  always  parallel  to 
the  front  axle.  Consequently,  the  levers  must  be  made  slotted  or 
telescopic.    The  result  of  this  combination  of  movements  is  an 


Fie.  317.    Pfttented  Enfjaah  Stoerins  Derke.  SiUd  to  b«  Tht^jnthtmUy  P«rf«fi 

absolutely  correct  angle  to  both  wheels  for  any  angle  ipf  kxdc.    Thin 
can  be  explained  by  a  reference  to  the  diagram* 

In  Fig.  316  the  prolongations  of  the  wheel  center  Vtnen,  r/r  rarli i  rif 
turning,  do  not  strike  the  center  line  of  the  rear  axle — abcmt  whicrh 
they  are  supposed  to  turn — at  a  common  pointy  the  difference  being 
the  amount  they  are  out  of  true,  viz,  the  distance  between  the  priintn 
0  and  P.  If  Fig.  317  be  lettered  to  correspond  with  Fig.  315,  the 
im>longatioDs  of  the  knuckle  center  fines  AP/f  and  IiBF  in 
fig.  316  beoome  the  two  con  verging  fines  AF/J  and  t\BO  UMt^t^^ 


450 


GASOLINE   AUTOMOBILES 


at  the  poiut  0  on  the  center  line  LMO  of  the  rear  axle  prolonged. 
This  is  as  it  should  be  and  shows  the  case  of  correct  steering  and 
turning. 

In  this  case,  all  four  wheels  are  turning  about  the  point  0,  the 
two  rear  wheels  with  the  radii  OM  and  OL,  and  the  two  front  wheels 
with  the  radii  OFi  and  (fl,,  respectively.  This  gives  a  theoretically 
correct  case  in  whiih  all  wheels  will  round  any  curve  as  they  should 
and  not  slip  or  slide  around,  damaging  the  tires  in  the  process.  The 
Davis  ty[>e  of  steering  gear,  it  may  be  remarked,  is  not  in  general 
use,  its  cohstruction  adding  a  number  of  parts  to  the  more  usual  form, 
shown  in  Fig.  31H,  which  gives  close  enough  results  for  average  use. 

Like  the  sliding-gear  transmission,  a  steering  gear  is  a  form  of 
mechanism  which,  although  used  on  nearly  all  automobiles,  is,  from 
a  thettretical  and  mechanical  standpoint,  far  from  what  it  should  be. 

General  Characteristics  of  Steering  Gears.  Standard  Typea. 
The  movement  or  deflection  of  the  front  road  wheels  is  obtained  by 


GASOLINE  AUTOMOBILES 


451 


through  a  fairly  large  arc,  according  to  the  capacity  and  design  of 
the  steering  gear. 

As  the  ball  arm  swings  through  its  arc,  the  drag  link  attached  to 
it  rises  and  falls  slightly,  the  movement  being  indicated  by  the  dotted 
lines  in  Fig.  318.  The  partial  circular  motion  in  a  vertical  plane  ia  ' 
converted  from  the  rotation  of  the  steering  gear  in  a  horizontal  plane 
by  several  methods.  The  gear  shown  in  Fig.  319  is  known  aa  the 
worm  and  sector  type,  which  is  illustrated  in  Fig.  318. 

In  Fig.  319  the  steering  column  or  post  CD  carries  a  worm  F 
which  is  in  mesh  with  the  gear  E. 
Rotating  the  column  CD  in  the 
direction  indicated  by  the  arrows, 
or  counter-clockwise,  will  result 
in  the  worm  turning  in  the  same 
direction.  The  gear  E  will  rotate 
on  its  horizontal  shaft  in  a  down- 
ward movement,  as  shown  by  the 
arrow,  and  as  the  ball  arm,  or 
lever,  is  attached  to  the  shaft,  the 
member  L  will  move  backward, 
or  to  the  left,  as  shown  by  the 
arrow  intersecting  the  ball.  With 
the  worm  type  the  two  gears  are 
usually  in  two  different  planes 
at  right  angles  to  each  other,  one 
vertical  and  the  other  horizontal. 
This  is  an  advantage  in  that  it 
lends  itself  readily  to  the  con- 
stnictioQ  of  a  simple  steering- 
gear  system.  Thus  the  post  ia  in  a  vertical  or  modified  vertical  line, 
as  is  also  tiie  motion  of  the  steering  arm,  and  the  consequent 
movement  of  the  steering  rod  is  more  or  less  confined  to'a  vertical 
plane.  With  the  worm  and  gear  thb  is  obtained  in  a  simple  manner. 
The  gearshaft  is  in  a  horizontal  plane  passing  through  the  center  line 
of  the  worm.  If  the  worm„  rotates  in  a  direction  which  approxi- 
mates a  horizontal  circle  around  a  vertical  axis,  the  worm  gear  will 
turn  in  a  vertical  plane  about  a  horizontal  axis.  A  lever  attached 
to  the  end  (rf  this  shaft  will,  consequently,  move  ia  the  denind. 


4S3 


GASOLINE  AUTOMOBILKS 


plane — the  vertical  one  mentioned  before — and  the  desired  requii*- 
ments  are  met. 

The  conversion  of  rotary  motion  in  a  horizontal  plane  to  partial 
rotation  in  a  vertical  plane  is  shown  in  Fig.  ^20,  the  action  here  being 
slightly  amplified.  The  steering,  or  hand,  wheel  .1  with  spokes  B  is 
turned  to  the  left,  turning  the  steering  coluttin  C  (a  hollow  tul>e)  in 
the  direction  indicated  by  the  small  arrow.  I)  is  the  steering  gear 
with  its  ball  arm  E.  The  turning  of  the  hand  wheel  moves  the 
ball  end  F  and  drag  link  backward.  The  front  end  of  the  drag  link 
is  attached  to  the  steering  knuckle  M  at  //  and  turns  about  the 
center  line  KL  of  the  steering  knuckle  ./,  the  end  turning  through 


n 

M.t  M 


GASOLINE  AUTOMOBILES 


453 


the  road  wheels  any  turning  movement  imparted  by  the  driver 
without  reveraing  or  carrj-tng  back  to  the  operator  the  original  move* 
ment  of  the  road  wheels. 

Many  attempts  have  been  made  to  substitute  another  form  of 
mechanism  for  steering  gears;  this  consists  of  various  rod,  lever, 
chain,  and  spring  combinations.  All  of  these  have  failed,  lioweveTt 
because  they  lacked  the 
fundamental  reauisite  of 
irreversibility. 

Aside  from  the  many 
schemes  mentioned  which 
seek  to  avoid  the  use  of 
the  regular  gear  in  the 
standard  manner,  there 
have  been  a  number  of 
unsuccessful  attempts  to 
avoid  its  use  in  other 
ways.  Fig,  321  shows 
some  of  the  gears  which 
have  been  tried.  At  /  b 
seen  a  device  in  which  the 
rotation  of  a'  Urge  bevel 
gear  turned  a  smaii  bevel 
pinion,  the  rotation  of  the 
latter  ser\'iiig  to  screw  a 
long  straight  lever  with  a 
threaded  inner  end  into  or 
out  of  the  interior  of  the 
threaded  be\-d  jnaion. 

In  the  figure.  .V  is  the 
actuating  bevd  turattl  by 
the  movement  ol  the  opcnfjr'i  iias^t,  while  0  in  it^  xftniUr  Mto* 
ated  be^'d  {ndkiD.  Vi'itbin  tii'a  u  «*ri  ti^.  wim>  rt^\  H  'A  the 
lever  J,  the  ball  at  tke  outer  oA  \^t>^  mta^'^tfh  Ut  'ij^t  'Mtmnn 
knudtle.  Since  tbe  berd  afrwft  ]f/vt  a  3^*a%  d/^al  td  ^/»*t  'tt,  Irft^X; 
while  the  vonn  armtgtwect  aivi  the  ^'wiin^  lu^/t.  '4  ^'t^.  '^rtn  in 
its  bearii^s  did  Ekewue,  tiw  xmaX  tMim.  Ut  torn  t>.ut  nuvtt  nanf.  i>w» 
enomioas.    At  2  b  dwwn  urxiier  fona,  ■m^Jt^  i^  the  ^fJtMtAmnd 


mi  GASOLINE  AUTOMOBILES 

arrangement;  a  small  bevel  N  attached  to  the  steering  post  A'  turns 
the  larger  bevel  0,  which  is  pivoted  at  the  axis  M  about  which  the 
lever  J  attached  to  the  segmental  bevel  0  tiu-ns. 

A  most  peculiar  arrangement  is  shown  at  .?,  this  being  a  com- 
bination of  a  worm  and  nut,  two  levers  and  a  steering  arm,  as  well 
as  a  connecting  link  for  the  two  levers.  Turning  the  hand  wheel 
turns  the  worm,  which  moves  the  nut  up  or  down.  Since  the  nut 
is  connected  by  means  of  the  link  to  the  lever,  the  motion  of  tlie 
nut  up  and  down  is  transmitted  to  the  short  lever;  this,  in  turn, 
moves  the  long-arm,  or  steering,  lever.  In  the  figure,  A' is  the  steering 
post.  A'  the  worm,  0  the  nut,  P  the  connecting  link  pivoted  at  the 
two  ends  T  and  S,  Q  the  short-arm  lever,  and  J  the  steering  lever, 
the  two  latter  being  integral  and  pivoted  at  the  point  R.  At  4 
is  shown  a  combination  of  a  double  internal  wonn  with  a  rack  and 
gear.  In  this,  the  turning  movement  of  the  inner  worm  causes  tiie 
outer  worm  to  travel  up  and  down,  l-'pon  the  exterior  of  this  outer 
worm  is  cut  a  rack  which  is  meshed  with  the  gear,  its  up  and  down 
movements  turning  the  gear  around  and  thus  effecting  the  steering, 
the  steering  lever  being  attached  to  the  gear.  N  is  the  iaterntJ 
worm,  0  the  external  worm  with  the  exterior  rack,  P  the  gear  which'J 


GASOLINE  AUTOMOBILES 


455 


and  parallel  with  the  axis  of  the  shaft  on  which  the  gear  turns.  In 
bevel  gears  the  teeth  taper  toward  a  point  and  are  inclined  to  the 
axis  of  the  shaft.  Another  construction  is  the  spiral  gear.  Both 
types  may  be  made  reversible  and  irreversible  as  desired. 

Womi-Qear  Types.  With  a  very  few  exceptions,  automobile 
engineers  favor  the  worm  tj-pe  of  steering  gear,  and  it  will  be  found 
on  the  highest  priced  cars.  It  has  the  advantage  of  being  irreversible 
and  b  utilized  in  several  forms.  In  the  worm  class  of  gears,  some  tj'pes 
are  closely  related,  while  others  varj-  widely.  For  example,  the  com- 
plete sector  and  gear  tjpe 
differ  only  in  that  the  wheel 
operated  by  the  worm  makes 
a  complete  circle  or  part  of 
a  circle.  The  full  gear  can 
be  turned  through  90  degrees 
and  replaced  on  the  shaft 
without  presenting  a  new 
surface  to  the  worm.  Some 
hold  that  the  worm  must  be 
subject  to  some  wear,  espe- 
cially where  it  b  most  used. 
They  contend  that  turning 
over  the  pinion  brings  new 
teeth  to  engage  with  the 
worm  and  that  these  teeth 
ivill  not  mesh  properly  when 
turned  at  an  angle  of  from 
20  to  ."iO  degrees. 

Worm  and  Pariial  Gear. 
Fig.  322  illustrates  a  gear  of  the  worm  and  partial  gear  type. 
Advantages  claimed  for  the  design  are  durability,  ease  of  action, 
and  adjustability  to  wear.  The  parts  are  accurately  cut  and  hard- 
ened, and  the  worm  is  provided  with  a  ball  thrust  on  either  side. 
With  this  type,  the  teeth,  which  are  in  the  middle  of  the  sector 
and  in  mesh,  perform  the  greatest  work  when  the  car  is  driven  in 
a  straight  line  and  are  most  susceptible  to  wear.  To  compensate 
for  this  wear,  the  center  teeth  are  cut  on  a  slightly  less  pitch  radius 
so  that  lost  motion  may  be  eliminated  without  affecting  the  upper 


fit.  322.     WoTi 


456  GASOLINE  AUTOMOBILES 

and  lower  teeth  of  the  sector  and  to  prevent  binding  when  turoiii^ 
at  right  angles.  In  the  Illustration,  A  is  the  steering  column  to 
which  the  worm  f  is  secured,  D  is  the  sector  in  mesh  «-ith  the 
worm,  E  is  the  ball  arm,  or  lever,  B  the  gear  housing,  F  the  spark 
and  throttle  bevel  gears  and  levers,  and  G  the  lubricant  plug. 

Adjustment.  Two  principal  adjuBtmenta  are  provided.  End 
play  of  the  worm  is  eliminated  by  lw>s(ming  the  jamb  nuts  and  lock 
screws  on  the  column  housing.  Displacing  the  oil  plug  0  will  dis- 
close an  adjusting  collar  which  is  set  with  a  screwdriver.  Adjust 
collar  until  all  play  is  eliminated,  but  the  worm  must  turn  easily. 
The  lock  screws,  above  referred  to.  are  so  located  in  the  gear  hou.«ing 
that  when  one  is  directly  over  a  slot  in  tlie  arljuittiiig  cuilur  the  other 
is  between  two  slots,  fonsequently,  after  adjusting  the  collar  it  is 
essential  that  the  proper  screw  be  selected  for  locking  the  adjustment. 
Both  locking  members  nin.it  he  prevented  from  turning,  by  using  the 
nuts.  Wear  of  the  teeth  of  the  worm  and  sector  may  Ite  eliminated 
by  means  of  an  eceentric  bushing,  which,  when  turned,  moves  tlie 
sector  into  a  closer  relation  with  the  worm.  Tins  is  accomplished  by 
removing  a  locking  screw  at  the  left  of  the  hall  arm.  and  moving 
the  arm,  which  turns  the  eccentric  buiihing.     In  case  of  extreme  wvaTj 

\t  mnv  hp  nPf«=carv  tn  (lionloo*  fhn  lioll  »-m  «n,l  «.>t  .I.b  I™ 


i 


GASOLINE  AUTOMOBILES 


be  attached  to  but  one  of  the  turning  gears,  the  other  gear  with 
its  actuating  worm  13  useless.  The  inventor  doubtless  intended 
the  two  worms  to  oppose  each  other  and  thus  be  self-sustaining  as 
to  thrust,  but  such  would  n^t  he  the  case,  the  actual  thrust  being  in 
opposite  directions  in  the  two  cases  of  the  upper  and  lower  worms, 
the  total  thus  being  double  the  usual  amount. 

Adjustment.  The  part  most  subject  to  wear  is  that  section  of 
the  gear  which  meshes  with  the  worm  when  the  front  wheels  are 
traveling  in  approximately  a  straight  line.  Because  of  this  wear,  the 
teeth  of  the  wheel  are  subject  to  deterioration.     Usually  the  adjust- 


Fia.  323.     Typical  Wotin  tad  Full  Gear  Stntioc  Deviw 


ment  for  the  wear  is  made  by  bringing  the  worm  into  a  closer  relation- 
ship with  the  gear  by  using  the  eccentric  bushings  which  support  the 
worm  shaft.  This  adjustment  b  practical  when  the  lost  motion  is 
due  to  poor  adjustment  rather  than  to  wear  of  the  teeth.  With  the 
majority  of  tj'pes,  it  is  possible  to  displace  the  steering  arms,  move 
the  steering  wheel  about  half  a  turn,  then  replace  the  worm  wheel  so 
that  an  unworn  section  opposite  the  worn  teeth  will  be  brought  into 
engagement  with  a  comparatively  unwom  portion  of  the  worm 
proper.  The  eccentric  busings  in  this  case  can  be  utilized  to  obtain 
a  correct  meshing  of  the  worm  and  gear  teeth.    End  play  of  the  wonn 


4S8^  CASOLINE  AUTOMOBILES 

tan  he  rfmnvt'ii  hy  adjusting  the  ball  thrust  bearings  on  either  side 
of  the  wiirni.  Sninftimes  these  bearings  become  dry,  or  the  lubri- 
cant becomes  gummy,  causing  the  shaft  to  turn  hard.  Wear  of  plain 
bushings  in  the  steering-gear  case  is  responsible  for  lost  motion;  the 
remedy  is  to  replai*  the  bushings  with  new  members. 

Worm  and  Siit.  Next  to  the  worm  and  gear,  either  full  or 
partial,  the  form  of  steering  gear  most  used  is  the  worm  and  nut, 
which  is  made  in  sevenil  different  combinations.  Thus,  the  nut  may 
operate  the  steering  lever  directly  through  the  medium  of  a  secondary 
lever,  or  it  may  actuiite  a  block,  which,  in  turn,  moves  either  the 
lever  direc-t  nr  the  sfnindary  lever.     In  Fig.  325  another  form  of 


GASOLINE  AUTOMOBILES 


Having  the  nut  in  two  widely  separated  parts  reduces  the  wear 
on  each,  since  the  bearing  surface  is  spread  out  more  than  would  be 


Fi|.  3M.    SUntaw  Gtmt  U»Bd  on  H«vy  MiubsCUn  Truclu 

the  case  with  an  uncut  nut.    In  addition,  the  split  nut  allows  the 
changing  of  the  ball-end  lever  at  any  and  all  times. 


GASOLINE  AUTOMOBILES 


In  Fig.  326  is  shown  a  form  ol 
wonn  and  nut  steering  gear  which  is 
used  on  very  heavy  trucks  and  com* 
mcrical  cars.  In  this  gear,  the  double 
worm  is  u-sefl ;  the  inner  worm  cnrries, 
at  its  lower  end,  a  block  which  is  piv- 
oted ill  a  combination  lever  and  shnft. 
to  which  the  steering  arm  is  attached, 
In  the  figure,  A  is  the  hand  wheel 
turning  the  rod  It  within  the  steering- 
post  tube  ('.  This  nxl  is  driven  into 
and  keyed  Ht  its  lower  end  to  a  mem- 
ber D  which  has  internal  worm 
threads.  Another  niemlK-r  E  has  a 
circular  upper  end  on  which  are  worm 
threads,  while  its  lower  end  is  slotted,  ■ 
Tlie  worm  at  the  npper  end  mesbes 
with  the  hiternal  worm  threads  in 
piece  D,  while  the  lower  slotted  end 
carries,  between  the  two  arms  of  the 


GASOLINE  AUTOMOBILES  461 

« 

extension  of  the  shaft,  must  tiun  the  shaft.  To  this  arm  is  attached 
the  steering  lever,  so  the  latter  must  move.  Although  a  rather  com- 
plicated gear  to  explain  and  also  to  make,  this  gear,  when  finished,  is 
an  excellent  one,  and  has  been  used  for  five  or  six  years  on  heavy 
trucks  with  excellent  results. 

The  Winton  steering  gear.  Fig.  327,  is  not  decidedly  different 
from  the  one  just  shown,  as  will  be  noted  by  a  close  inspection  of  the 
parts.  A  is  the  internal  worm,  which  is  turned  by  the  hand  wheel, 
while  engaging  this  worm  are  the  block  B  and  pin  C,  the  block  being 
partly  cut  away  to  show  the  engaging  gear  teeth.  This  block  moves 
the  jaw  arm  of  the  steering  lever  D.  This  jaw  is  not  complete  in 
this  gear,  but  is  cut  away  to  save  weight.  The  jaw  arm,  too,  is  con- 
nected directly  with  the  steering  lever,  the  jaw,  arm,  and  shaft  making 
one  piece.  The  light  work  to  which  this  was  put  made  possible  the 
economy  in  the  number  of  pieces  and  in  the  weight  of  each.  As 
before,  turning  the  hand  wheel  turns  the  worm,  which,  in  turn,  moves 
the  block  and  pin  up  and  down  and  thus  moves  the  jaw  arm,  which 
moves  the  steering  lever. 

Adjustment.  The  adjustment  for  lost  motion  in  the  worm  and 
split-nut  type  of  gear  is  generally  made  by  loosening  a  cap  screw  on 
the  column  and  screwing  down  an  adjusting  nut  which  has  a  right- 
hand  thread.  This  adjusting  nut  acts  directly  on-  the  thrust  bearing, 
forcing  the  screw  and  half  nuts,  which  slide,  against  the  yoke  rollers. 
In  making  the  adjustment  to  a  gear  of  this  type,  it  is  advisable  to 
turn  the  road  wheels  to  the  extreme  angle  position,  because  the  gear 
is  the  least  worn  at  this  point,  and  if  it  is  adjusted  only  enough  to 
take  up  the  play  when  in  this  position,  there  will  be  danger  of  binding. 
Sometimes,  when  the  adjustment  is  made  with  the  road  wheels  straight, 
the  gear  will  bind  at  the  extreme  positions. 

Worm  and  Worm.  In  the  worm  and  worm  form  of  steering  gear 
there  is  ia  worm  within  a  worm,  not  wholly  unlike  the  ones  just 
described.  Fig.  328  shows  an  example  of  this,  which  has  a  worm  C 
attached  to  the  steering  rod  H,  which  is  turned  by  the  steering  wheel 
A.  Within  and  without  this  are  worm  threads,  an  externarworm 
B  meshing  with  the  internal  worm  on  the  inside  of  C,  while  an  internal 
worm  D  meshes  with  the  external  worm  on  C  The  action  of  turn- 
ing the  hand  wheel,  then,  moves  one  of  these  up^axA  «bxA  XJoa  ^"Oc^t 
J ] 


m  GASOLINE  AUTOMOBILES 

The  lower  end  Bi  of  the  inner  worm  member  presses  Hgaimt 
a  hardened  end  of  the  steering-lever  arm  E,  while  the  lower  end  /J. 
of  the  outer  worm  member  presses  against  the  other  hardened  emi 
El  of  the  same  piece.  There  is  no  lost  motion,  or  play,  in  the  gear; 
when  the  hand  wheel  is  turned,  one  worm  rises  and  the  other  falls, 
as  just  described;  the  piece  E  will  let  one  end  rise  and  the  other  fall, 
as  it  is  acted  upon  by  the  lower  extremities  of  tlie  two  moving  worms. 
This  piece  is  pivoted  at  F  and  carries  at  Its  outer  end  the  steeriiiff 
lever  G,  which  thus  moves  in  the  customary  manner.  WitbJn  the 
steering  post  arc  the  spark  and  throttle  tube  and  rod  /  and  J,  which 


GASOLINE  AUTOMOBILES  463 

bevel  pinioD  moves  the  bevel-gear  sector  back  and  forth  as  it  b  turned, 
this  motion  being  transferred  to  the  steering  arm  attached  on  the 
same  shaft  to  which  the  bevel  sector  is  secured.  This  type  of  gear  is 
said  to  be  effective,  but  it  is  not  irreversible,  and  shocks  to  the  road 
wheels  may  be  imparted  to  the  steering  wheel  and  move  it. 


Adjustment.  The  bevel  and  sector  gear  haa  two  adjusbDnats. 
The  pinion  may  be  moved  up  or  down,  as  required,  by  unlocking  the 
clamp  bolts  (one  of  which  is  shown  at  D)  which  pwm\\s\)aft  TawVi^^A 
the  entire  ^te^g  co/«qiq  yp  or  dgira  w  «a  \ft  QV^^aJ©.^  'giw^R^ 


494 


GASOLINE  AUTOMOBILES 


relative  position  to  the  pinion  and  its  sector.  The  position  of  the 
sector  endwise  may  be  adjusted  by  the  block  member  A,  which  bean 
against  a  roller  guide,  forcing  the  sector  into  meah  more  or  less  closely 
with  the  pinion.  The  spring  E  is  provided  to  prevent  rattling,  and 
the  screw  //  is  a  guide  for  the  plunger  and  should  not  be  disturbed 
in  making  the  adjustment. 

Hindley  Worm  Gear.  Tliere  are  a  number  of  things  aWut  the 
Hindley  type  of  worm  which  make  it  an  excellent  one  to  use  for 
steering  gears.  A  realization  of  this  advantage  is  bringing  about  a 
greatly  increased  use  of  this  form;  so  it  will  be  appropriate  and  timely 
to  look  into  it.s  form,  i-oii- 
structioii,  and  advantiigca. 

The  question  of  what 
makes  the  Hindley  different 
from  other  worms  naturally 
arist<6.  The  ordinary  womi 
has  the  same  diameter  from 
one  end  to  the  other,  the 
blank  before  the  cutting  o{ 
the  teeth  resembling  a  se»^ 


rikmi\]-i 


GASOLINE  AUTOMOBILES  465 

This  fonn  of  worm  is  used  for  the  double  reason  of  presenting 
more  wearing  surface — since  it  has  at  least  three  teeth  in  contact 
at  any  one  time,  as  compared  with  one  or  at  most  two  in  the 
ordinary  worm^— and  greater  resistance  to  reversibility.  The  worm 
is  used  for  steering  gears  because  it  is  partly  or  wholly  irreversible, 
its  motion  being  a  sliding  one;  nevertheless,  all  worms  may  be 
so  cut  as  to  be  either  wholly  or  not  at  all  reversible.  The  sliding 
motion  of  the  two  parts  in  contact,  as  opposed  to  the  rolling  motion 
in  the  case  of  other  mechanical  movements  of  a  similar  nature,  is 
greatly  increased  if  there  are  three  teeth  in  contact  instead  of  the 
more  usual  one.  If  the  friction  of  sliding  be  increased,  the  amount 
of  reversibility  will  be  decreased  in  the  same  proportion,  for  the  added 
sliding  friction  will  increase  the  natural  reluctance  of  the  worm  to 
transmit  power  backwards.  So  much  is  this  the  case  that  it  pays 
to  use  the  Hindley  form,  despite  its  greatly  increased  cost  of  cutting. 

Ford  Steering  Gear.  The  steering  mechanism  of  the  Ford  car — 
a  patented  construction — differs  radically  from  the  conventional 
types  in  that  its  hand  wheel  does  not  directly  rotate,  or  turn,  the  steer- 
ing column  or  rod,  but  it  imparts  the  necessary  turning  movement 
through  the  gearing  and  the  use  of  a  small  shaft  to  which  the  hand 
wheel  is  attached.   A  phantom  view  of  the  gearing  is  shown  in  Fig.  331 . 

The  steering  column  with  its  short  shaft  and  drive  pinion  is 
enclosed  in  a  tube  or  housing  which  is  set  at  an  angle  and  bolted  to 
the  dash.  The  housing  does  not  extend  the  entire  length  of  the 
column,  as  the  lower  end  of  it  is  mounted  in  a  bracket  that  is  rigidly 
bolted  to  the  frame.  The  steering-gear  post,  or  column,  has  a  tri- 
angular flange  at  right  angles  to  the  rod,  and  each  point  of  the  flange 
has  an  integral  stub,  or  pin,  carrying  a  small  spur  pinion.  The  center 
of  the  rod  is  drilled  and  bushed  to  take  a  small  shaft  to  which  a  fourth 
pinion,  or  drive  pinion,  is  keyed.  The  upper  part  of  the  housing  is 
shaped  so  as  to  provide  a  gear  case,  and  the  inner  periphery  of  this 
case  is  cut  to  obtain  spur  teeth  or,  in  other  words,  an  internal  ring 
gear.    This  gear  is  stationary. 

The  hand  wheel  is  attached  to  the  short  shaft,  and  its  drive 
pinion  is  held  in  place  by  a  brass  cover  of  the  internal  gear  case.    As 
the  drive  pinion  of  the  shaft  is  in  mesh  with  the  three  pinions  mounted 
on  the  stubs  of  the  steering  column  proper,  and  these  iVvxee  -^VK^s^jka* 
are  in  mesh  with  the  internal  ring  gear,  any  movemexvt  o\  \>aRi  VwA 


4fi6 


GASOLINE  AUTOMOBILES 


wheel  will  rotate  the  drive  pinion  on  its  shaft.  This  movement  will 
cause  the  three  spur  pinions  to  rotate  in  an  opposite  direction  against 
the  internal  gear,  thus  reducing  the  movement  of  the  steering  column 
as  compared  to  that  of  the  hand  wheel.  The  three  spur  pimoiu 
compensate  for  any  pressure  of  the  drag  link  and  the  tie  rod. 

The  operation  of  the  Ford  steering-gear  mechanism  explains  the 
basic  principle  of  the  operation  of  the  hand  wheel;  that  is  why  the 
wheel  is  turned  iii  the  same  direction  that  the  driver  desires  the  car  to 


GASOLINE  AUTOMOBILES 


467 


Tbe  drag  link  of  the  Ford  steering  gear  differs  from  conventional 
designs  in  that  it  is  at  right  angles  to  the  frame  and  is  practically 
two-thitds  the  length  of  the  tie  rod.  The  end  of  the  steering  column 
is  provided  with  an  arm  carrying  a  ball,  and  the  drag  link,  or  steering- 
gear  connecting  rod,  as  it  is  listed  by  Ford,  has  a  ball-socket 
cap  which  fits  over  the  ball  of  the  steering  rod.  Tbe  drag  link  also 
has  a  ball  socket  at  its  other  end,  which  fits  over  a  ball  arm  on  the  tie 
rod.  The  tie  rod,  called  the  spindle  connecting  rod  because  it  con- 
nects the  spindles,  is  provided  with 'yokes  at  either  end,  and  these 
yokes  are  pivotally  connected  to  the  spindles  by  a  bolt  passing 
through  them  and 
through  an  eye  in  the 
spindle.  The  Ford  drag 
link  differs  from  others 
in  usual  practice  in  that 
it  moves  to  the  right  and 
left,  white  those  used  on 
other  cars  move  forward 
and  backward.  No  pro- 
vision is  made  with  tbe 
Ford  drag  link  for  absorb- 
ing shocks  or  for  auto- 
matically compensating 
for  wear  as  usually  is  the 
case  with  the  conven- 
tional type  of  drag  link. 

Semi-Reversible  Qear.  The  steering  gear  used  on  commercial 
cars,  particularly  trucks  ranging  from  3-  to  7-ton  capacity,  must  not 
only  be  capable  of  operation  with  a  minimum  effort,  but  it  must 
absorb  a  great  many  of  the  minor  shocks  and  a  per  cent  of  the  larger 
shocks.  The  semi-irreversible  tj'pe  is  most  favored  because  of  the 
above-named  reasons.  The  design  shown  in  Fig.  382  is  of  the  screw 
and  nut  type.  The  nut  is  a  solid  piece,  completely  enveloping  the 
screw,  and  the  threads  of  the  screw  are  in  constant  and  complete 
engagement  with  the  threads  in  the  nut.  The  screw  lias  a  rotary 
motion  and  the  nut  has  a  longitudinal  motion.  The  means  of  trans- 
mitting this  longitudinal  motion  of  the  nut  to  t\ie  tq\».t5  TonfCxwi.  *A 
the  steen'ng  arm  is  by  circular  discs  at  the  \oweT  eai  cS.  \3Re.  wmX. 


Us.  332.    Screw  u 


I  Nut  Omf  U»d  on  TruHo 


488  GASOLINE  AUTOMOBILES 

These  discs  present  constant  bearing  surfares  to  the  recesses  in  Uw 
nut,  and  are  provided  with  slots  into  which  the  projecting  levers  from 
the  rocker  shaft  fit.  The  screw  pulls  the  nut  up  or  down  in  the 
housing,  and  there  is  nti  tendency  /or  this  nut  to  be  moved  sideways. 


Hdji^ting  tlut  B 


GASOLINE  AUTOMOBILES  469 

in  Fig.  333,  which  is  a  semi-irreversible  wonn  and  gear,  the  removal 
may  be  accomplished  by  displacing  the  control  levers  at  the  top  of 
the  column  and  dropping  the  unit  down  through  the  frame.  The 
adjustment  of  this  type  for  end  play  is  made  by  loosening  the  locking 
nut  A  and  turning  down  the  nut  B  until  the  play  is  eliminated. 

STEERINQ-QEAR  ASSEMBLY  TROUBLES  AND  REPAIRS 

Lost  Motion  and  Backlash.  Lost  motion  of  the  steering  wheel 
does  not  always  indicate  that  the  steering  gear  is  at  fault,  for  wear  in 
the  steering-gear  assembly  usually  takes  place  first  in  the  clevis  pins, 
yokes,  and  connections  of  the  drag  link.  The  spindles,  spindle  bolts, 
and  wheel  bearings  are  factors.  Despite  the  fact  that  the  front  road 
wheels  are  deflected  but  a  few  degrees  the  spindles,  bolts,  or  bushings 
may  be  worn,  as  these  parts  are  subject  to  radial  and  thrust  loads. 
The  spindle  bolt,  which  does  not  move,  tends  to  wear  oval;  adding  to 
this  tendency  the  wear  of  the  spindle  bushings,  one  has  considerable 
lost  motion  to  contend  with.  Wear  of  the  wheel  bearings  contributes 
to  the  apparent  lost  motion  of  the  steering  gear  as  do  the  connections 
of  the  drag  link.  Taking  all  of  these  factors  into  consideration,  and 
allowing  but  a  small  fraction  of  an  inch  for  play  of  each  worn  part, 
the  sum  total  may  result  in  considerable  movement  of  the  hand  wheel 
before  the  road  wheels  are  deflected. 

Lost  Motion  in  WheeL  While  there  should  be  a  certain  amount 
of  movement  to  the  hand  wheel  before  it  actuates  the  road  wheels, 
the  lost  motion,  as  a  rule,  does  not  exceed  J  or  f  inch  when  the  gear 
is  new.  This  amount  is  essential  as  without  some  free  movement  the 
steering  of  the  vehicle  would  be  tiresome.  Wheels  may  be  keyed  or 
pinned  to  the  column.  When  play  exists  as  the  result  of  a  worn  key, 
pin,  or  slots,  the  remedy  is  to  re-cut  the  seats  and  make  and  fit  a  new 
key  or  pin.  With  some  types  of  wheels  the  use  of  a  wheel  puller  will 
be  necessary  to  displace  them.  Another  cause  of  lost  motion,  when 
the  wheel  is  tight  and  linkage  free  from  play,  is  a  loose  key  retaining  the 
worm  or  gears  of  the  steering  gear  proper.  A  simple  test  of  the  hand 
wheel  is  to  hold  the  tube,  or  post,  securely  and  move  the  hand  wheel. 
The  amount  of  play  in  the  drag  link  can  be  ascertained  by  grasping 
it  about  midway  and  trying  to  move  it  backward  or  forward  or  in  the 
normal  direction  of  travel.  Hold  the.  ball  arm  of  the  steering  ^^^ 
when  making  ibis  test. 


470 


GASOUXE  AUTOMOBILES 


The  amount  of  backlash  present  in  the  irreversible  and  semi- 
irreversible  types  of  steering  gears  may  be  determinefl  by  disconnect- 
ing the  drag  link,  grasping  the  ball  arm,  and  moving  it  up  and  down 
and  back  and  forth.  Worn  bushings  in  the  steering-gear  case  are 
frequently  the  cause  of  movement  of  the  column  as  a  whole.  Another 
component  that  should  not  be  overlooked  in  the  search  for  the  cause 
of  lost  motion  is  the  ball  arm.  Movement  of  this  member  on  its 
sliaft  can  usually  Ix'  eliminated  by  tightening  the  nut. 

STEERING  WHEELS 
Different  Forms  of  Hand  Wheels.     IVood  Rim.  'A  variety  of 
material  is  utilized  in  the  construction  of  the  wheel,  which  has  super- 


GASOLINE  AUTOMOBILES  471 

indicates  the  wood  monb^,  B  the  arms>  or  spokes,  which  have  a 
boss  through  which  the  screw  C  passes  into  the  wood.  The  hub  of 
the  spider  D  is  attached  to  the  steering  post  by  two  keys  E, 

Metal  Core  with  Wood  Covering.  When  the  wheel  design  is  made 
up  of  a  metal  core  the  ring  is  cast  on  the  spider  or  integral  with  it. 
Coverings  of  wood  concealing  the  ring  are  useil,  although  with  some 
types,  a  section  of  the  ring  may  be  noted.  This  type  of  wheel  pos- 
sesses great  strength  and  the  wood  veneers  can  be  secured  at  more 
frequent  intervals  than  in  the  design  previously  described. 

Different  Wheels  for  Commercial  Use,  Truck  Types,  For  the 
light  delivery  wagon,  taxicab,  and  similar  cars,  no  difference  in  the 
steering  wheel  is  made,  but  when  it  comes  to  the  heavier  service,  there 
is  a  need  for  a  heavier  wheel.  This  does  not  mean  a  heavier  rim 
only,  but  a  heavier,  more  rugged  gear  all  the  way  through.  The 
weight  on  the  front  wheels  of  a  heavy  truck  is  very  great,  and 
the  tires,  which  are  of  solid  rubber,  may  have  frictional  contact  with 
the  pavement  of  several  inches  in  width.  All  this  combines  to  make 
turning  the  vehicle  from  the  driver's  seat  more  difficult. 

For  this  reason  the  driver  must  have  a  greater  leverage,  wtiich 
means  a  larger  diameter  of  the  wheel.  Then,  too,  the  rim  should  be 
bigger  in  section  in  order  to  withstand  the  harder  use  of  commercial 
service,  and  to  provide  for  the  large  hands  of  the  operators.  Greater 
strain  upon  the  rim  of  the  wheel,  on  attempting  to  turn  heavier 
weights  with  it,  means  that  the  rim  must  be  fastened  to  the  spider  more 
securely.  This  means  more  arms,  the  four  generally  u«e<l  for  pleasure 
cars  being  increased  to  five  for  trucks.  While  this  helps  a  great 
deal,  since  it  provides  five  screws  instead  of  four,  it  is  not  sufficient^ 
and  most  of  the  big  trucks  today  are  equipped  with  steering  wheels 
in  which  the  rim  is  built  over  a  central  metal  rim  of  the  spider.  '^ 

Pleagure^^ar  Types,  Usual  pleasure-<!ar  practice  varies  from 
14-inch  up  to  IG-inch  wheels,  while  commercial  car  sisses  begin  at  16- 
inch  and  run  up  to  18-incfa  miieeb  on  light  trucks,  and  as  iiigb  as  20- 
and  22-incfa  wfaeeb  on  heavy  trucks.  Kim  sizes  vary  considerabl.\',  a 
favorite  for  touring  cars  being  an  ovsl  with  from  |-  to  {-inch  vertical 
height  and  a  length  of  about  1  ^  to  1 A  inches,  l^iese  figures  Imve  no 
connection  with  oommerdal  work*  the  smallest  being  1  inch  and  on 
up  to  li  inches  in  faeigfat,  with  the k^og  diameters  varying  from  1}  up 
to  If  iocfaea.    Far  qieed  work,  racing,  and  the  like,  it  is  usual  practice 


472 


GASOLINE  AUTOMOBILES 


for  tile  operator  to  wind  the  surface  of  the  wheel  with  string,  thl" 
giving  a  rough  surface  upon  which  the  hands  wiU  not  slip.  'Fliis  is 
practiced,  too,  by  many  truck  drivers,  who  claim  that  the  strains  n( 
steering  the  big  vehicle  are  not  felt  as  much  when  the  wheel  is  thus 
wound. 

To  preserve  llic  nice  appearance  of  the  steering  wheel  and  rilill 


GASOLINE  AUTOMOBILES 


473 


sions  and  humps,  between  which  the  fingers  find  a  good  resting  place. 
This  gives  a  good  grip,  as^e  under  side  of  the  wheel  seldom  gets  wet. 
Folding  Steering  Whei(».  Although  tilting  steering  wheels  were 
introduced  several  years  ago,  they  did  not  meet  with  favor  until  the 
Cadillac  adopted  them  as  standard  equipment.  The  wheel,  which  is 
18  inches  in  diameter  and  has  an  aluminum  spider,  is  hinged  to  drop 
downward,  a  design  facilitating  entrance  and  exit  at  either  side  of  the 
car  and  making  it  possible  to  attain  the  driver's  seat  without  squeez- 


ing. The  Cadillac  wheel  is  shown  in  Fig.  330,  while  that  used  on  the 
King  car,  illustrated  in  Fig.  337,  is  of  the  tilting  type.  To  operate 
the  design,  the  wheel  is  turned  until  the  wheel  spider  arm  carrying 
the  release  button  is  convenient  to  the  thumb  of  the  right  hand. 
The  button  is  pushed  to  the  right,  and,  by  using  both  hands,  the 
wheel  is  pushed  forward  and  upward.  The  Herff  type,  shown  in 
Fig.  338,  is  of  the  true  hinged  form ;  the  rim  is  thrown  uv  mvA.  w*.  «A. 
thewa^,  thatis,  tberim  oaly,  as  the  quadrant  ca,tT>•«v^^^3BftS^■^*'^ 


474 


GASOLINE  AUTOMOBILES 


throttle  levers  remains.     There  are  several  other  tj-pes  marketed,  but 
their  working  principles  are  similar. 

Throttle  and  Spark  Levers.    In  the  usual  case,  the  arms  o( 
the     steering     wheel    have    the 
quadrant  fur  tlie  spark  Hn<I  throt- 
tle levers  fastened  to  them.     The 
le\'ers  are   operated    within  the 
space  inside  of  the  rim  of  wooil 
nnd  above  the  spider  of  metal: 
the  latter  is  usually'  at  a  lower 
level  by  several  inches,  as  shown 
in  the  figure.     In  Fig.  334,  how- 
ever, the  quadrant  is  not  carried 
by  the  spider  arms,  but  on  a  sep- 
arate framework  0,  or  spider  of 
its  own.  up  above  the  hub  of  the 
wheel.     Over  this  frame- 
work the  spark  and  throt- 
tle levers  //  and  /  work, 
serrations  of  teeth  in  the 
niiadrant    nrnvRntins 


GAdOUNX  ACTOMOBILES 


tzs- 


jecting  doim  fron  k  C,  wk3t  dr  surtsLt:  rod  v&ack  aMants  tkt 
lower  end  of  dip  ai^  nfc  Ae  Icnr  m  dir  tiBHftL'  k  mmIhI  AR. 
F  is  the  lcnw*L'  pinttd  b  tfe  axle,  -wiath  anits  tkr  tw^wl  Imr 
E,  one  ann  of  vUcfa  ba$  the  gwria^  rod  anadvd  to  h  at  A.  wtfr 
the  otbo'  cairies  thr  msi^aoaatto^  rod  jociiD^  thr  t«\>  kaacUe^ 
together.  Since  tfar  pnxx  point  k  fimL  aur  momtct  n^wml  n^ 
the  knuckle  must  icsoh  in  as  iwinging  aboot  the  psrM  {iwait  and 

j    carrj'iiig  the  vliccls  vitli  it. 

,  This  moi-cment  b  impuied  by  die  ftraiu:  tvd  to  lix  «ai  B 

■•  '  of  the  arm  E.    Tbr  stcrtiiic  rod  itself  ^mplr 

I    <roiuiects  with  the  steoing  fevef  C,  sTinpjij 

<    back  and  forth  in  a  vrrtkal  pUne  with  the 

i    steering  knuckle  F.  ■wioA  sntgs  aroond  sod 

t  hack  in  a  bonxbotal  piaac,  and  imparts  (br 
movement  erf  the  ie\^  to  the  knitckle.  Since 
the  end  of  the  aeeriog  Ic^tr  nse«  and  falb  and 
the  end  of  the  lever  on  the  knuckle  mainiaina 


a  constant  Ie\-el,  altbou^  monng  in  a  cirde,  the  ml  must  haw  a 
universal  joint  at  one  end.  This  b  really  a  necessity  fiwu  tww  p^tints 
of  view:  to  allow  the  rear  end  to  move  up  and  down  verticallj-  whilv 
the  front  end  swings  around  in  a  circle;  and  also  to  allow  the  fn>nt 
end  to  swing  in  a  circle  set  in  one  horizontal  plane,  while  the  rear  «mI 
remains  stationary-  or  practically  so  in  that  plane.  In  short,  tlte  twtt 
ends  move  continuously,  each  in  its  own  plane,  but  the  twtt 
planes  never  coincide — the  one  is  alwaj-s  vertical,  while  the  othor 
always  stays  horizontal.  Thia  necessitates  at  least  one  uniwrmi 
joint.    Many  ipakers  play  oa  the  safe  ^de,  and  loww  thec»&t.cX 


.  a  iiuc  on  tne  outsiae 

itself  is  made  separately  am 
shaft,  or  axis.  After  this  a  s 
holds  the  sleeve  up  tiglit  agaii 
is  to  give  the  spherical  end  t 
dii 


Fif.  340.    ttlntnng  Lover 


thet 
insid 

side  of  it.  These  springs  not  on 
wear  as  well,  the  shoulder  again 
In  this  figure,  J  is  the  lower  end 
end.  This  lever  is  mounted  in  t 
the  steering  rod,  which  is  expan' 
this  being  designated  in  ♦'•"  " 


GASOUNE  AUTOMOBILES 


477 


is  disassembled  and  a  longer  sleeve  inserted  in  place  of  the  one  shown 
at  E.  On  the  other  hand,  ordinary  wear  is  compensated  for  by 
taking  up  on  the  collar  C,  first  loosening  the  lock  screw  V. 

In  Fig.  342,  a  rod  is  shown  assembled  at  the  top  and  disassembled 
into  its  components  at  the  bottom.    The  two  ends  differ,  one  being 


11 

il 

^^i LJ 

Fig.  Ml.     Adjiutabfe  Form  of  BaU-End  Stwring  Rod 

but  a  simple  yoke  with  a  plain  bolt  through  it,  marked  D.  The 
other,  however,  is  a  ball  end  with  an  adjustment  and  with  springs 
to  take  up  shocks. 

All  these  parts  are  marked  in  the  figure  and  may  be  located  by 
letter.  The  body  of  the  rod  is  marked  A,  the  expanded  end  B,  which 
has  a  groove  //  cut  in  it.  Into  the  inner  end  of  this  groove  is  fitted, 
first,  the  spring  F;  second,  the  two  halves  of  the  ball  socket  G;  and 


dilmimraiii 


F«.  343.     Cnw-Conoectioc  Rod  AsKmblcd  siid  In  PvU 

third,  another  spring.  The  sleeve  E  closes  the  outer  end,  and  over 
the  exterior  is  screwed  the  adjusting  nut  C.  The  nut  and  sleeve  are 
held  in  place  by  the  locking  pin  V,  which  passes  through  the 
outer  nut,  the  shell  end  of  the  rod,  and  the  bner  spacing  sleeve,  the 
ends  being  riveted  over  to  bold  it  in  place.    This  form  limits  theadjust- 


the  possibility  of  damage  if  a 
but  in  some  Instances  the  tic 

V 

Fis.  343.    Finuhod  SG.V.  Chrome 


K*.  344.     Ij'ft  Siptfim  Knuckle  a 

The  tip  ~-i  "        ■ 


GASOLINE  AUTOMOBILES  479 

Function  and  Shape  of  Steering  Knucldes.  The  steering  knuckles 
serve  as  a  pivot  for  the  road  wheels,  enabling  them  to  move  in  a  hori- 
zontal plane.  The  design  of  the  knuckle  depends  upon  the  axle,  and 
-the  pair  used  on  a  car  are  different  as  one  has  a  lever  for  carrj'ing  the 
drag  link.  Both  have  integral  spindles  to  which  the  tie  rod  is  attached. 
Figs.  343  and  344  illustrate  the  difference  between  the  knuckles. 


Fi«.  346.    Pulurd  ElHrinc  Geir  Parte 

Fig.  343  shows  a  right  knuckle,  forged  from  a  blank  of  chrome  nickel 
steel,  while  the  one  at  its  side  is  the  finished  part.  A  is  the  place 
for  the  outer  wheel  bearing,  B  the  position  of  the  inner  bearing,  C  the 
hole  for  the  pivot,  or  knuckle,  pin,  D  the  upturned  steering  arm,  and 
E  the  arm  to  which  the  tie  rod  is  attached.  Fig.  344  is  an  example 
of  a  left  steering  knuckle  of  the  same  pair,  both  before  and  o.fte'c 
machining.    The  letters  in  Fig,  343  app\y  to  ttvra  Vaxu^e. 


GASOLINE  AUTOMOBILES 


Lubrication  of  Steering-Qear  Assemblyt  Tlie  proper  lubrication 
of  the  steering-gear  assembly  adds  to  its  life,  but  this  work  is  not,  as 
a  rule,  thorough.  The  steering  gear  proper  should  be  packed  with 
grease,  the  ball  and  socket  joints  of  the  drag  link  and  stcering-«nii 
lever  with  a  light  grease;  the  clevis  pins  also  should  be  lubricated. 
The  steering-knuckle  pins  are  provided  with  either  grease  or  oil  cups. 
A  point  generally  overlooked  in  the  lubrication  of  the  steering 
gear  is  the  steering-post  spark  shaft  and  throttle-sector  anchor  tubi-, 
shown  in  the  illustration  at  Fig.  345,  which  is  of  interest  in  that 
it  illustrates  the  assembly  of  the  Packard  car.  The  post  carries 
the  control-box  unit.  The 
spurk  shaft  and  throttle  tube 
fn-iiuentlj'  lack  lubricant  and 
slinnld  be  cleaned  and  cunUtI 
«itli  a  graphite  grease  before 
rt-pliicing  when  the  gear  is 
I iciii^ reassembled.  The  lowxr 
extremity  of  the  spark  and 
throttle  members  carry  levtrs 
or  small  bevel  sectors  which 
operate  the  linkage  of  the  mm- 


GASOLINE  AUTOMOBILES 


481 


universal  joint  to  tnuismit  uniform  angular  velocity.  Its  design  was 
brought  about  by  the  fact  that  the  rate  of  transmission  of  angular 
velocity  through  a  universal  joint  is  not  even  when  the  shafts  are  at 
an  angle.  This  is  the  fundamental  difficulty  every  designer  of  a  front 
drive  has  to  overcome  or  suffer  the  twisting  of  the  axle. 

The  front  wheels  and  the  flywheel  must  rotate  at  practically  a 
uniform  speed,  at  least  through  each  revolution.  The  irregular  rate 
of  transmission  through  the  universal  joint  must  be  taken  up  aome- 


LaocbUn  Pedkl  MechAnMra 


where.  The  normal  action  of  a  universal  joint  at  certain  angles  is 
to  make  four  jerks  in  a  revolution,  as  it  has  four  fast  points  and  four 
slow  points.  The  Laughlin  joint  gives  uniformity  of  rotation  with 
75  per  cent  on  each  side  of  normal,  the  difference  being  taken  up  by 
the  flexibility  of  the  transmission  parts. 

Frietiort'Digc  Tranamisnon.  The  transmission  is  of  the  friction- 
disc  type,  but  the  disadvantage  of  this  form  of  drive — the  fact  that 
the  control  is  reversed — is  eliminated.  The  usual  clutch  control  is 
provided,  but  the  pressure  is  automatic.  This  pressure  is  obtained 
by  an  eccentric  cminection  by  means  of  which  designers  obtun.  \n«- 


482 


GASOLINE  AUTOMOBILES 


versihle  application  of  spring  pressure.  The  transmiasion  locks  ttt  the 
correct  pressure  tliniugli  the  friction  of  the  eccentric.  The  spring 
controlling  the  friction  for  driving  proviik-s  the  pni[)er  pressure  fur 
running,  but  it  is  not  sufficient  for  starting  or  climbing  long  hills  in 
the  low  gear.  The  pedal  shaft  operates  a  ilog  tluit  presses  down  im 
the  eccentric  sheave  extension.  To  dc-clutch,  the  operator  presses 
the  pedal  down,  releasing  the  clutch.  The  pedal  has  two  points  at 
which  it  latches,  providing  extra  pressure,  and  an  extra  spring  is 
brought  into  ser\'ice  for  the  high  and  low  s(>eed.  This  spring  opt^rates 
through  a  toggle  linkage.  As  the  pedal  rises,  the  applied  power 
increases.  When  the  car  attains  momentum,  the  driver  depresses 
the  peflal  until  it  latches.  The  running  pressure  is  sufficient  to  hold 
the  engine  in  all  gears  except  the  low  and  reverse. 

Control.  Complete  control  is  obtained  through  one  gearshaft, 
the  lever  working  forward  for  progressive,  and  back  for  reverse.  Auto- 
matic latching  is  obtained  in  e\'ery  gear,  the  latch  working  in  sockets 
sunk  in  the  jackshaft.  Chain  drive  is  employed  between  the  trans- 
mission and  front  axle.  The  brakes  are  located  on  the  rear  axle. 
Fig.  .147  shows  the  method  of  obtaining  a  conventional  pcdul  control 
of  the  transmission  through  tlie  )rre\'er3ible  application  of  sprii^ 


GASOLINE  AUTOMOBILES  483 

force  is  applied  to  the  system,  and  no  matter  in  what  portion  the 
wheels  may  be. 

The  advantage  of  the  four-wheel  drive  and  with  it  the  four- 
wheel  steer  and  brake  is  granted  by  eminent  engineers,  as  is  also  its 


Fig.  348.    Kde  View  of  ■  Fout-Whwl  Drivs,  StHr,  and  Brkke  Motor  Truck 

necessity  for  heavy  commercial  trucks,  but  its  use  has  not  been 
extensive  for  the  simple  reason  that  it  is  a  complicated  arrangement 
at  best.  In  many  cases,  the  design  has  been  so  complicated  and 
unmechanical  as  to  cause  failure,  and  the  reports  of  these  troubles  have 
given  the  four-wheel  driving,  steering,  and  braking  device  a  sort  of 
visionary  air,  so  that  any  one  talking  of  it  is  supposed  to  bea  dreamer. 
Such  is  not  necessarily  the  case,  for  many  different  practical  four- 
wheel  combination  driving,  steering,  and  braking  devices  have  been 
brought  out,  built,  tested,  and  proved  efficient. 

A  number  of  four-wheel  designs  for  commercial  cars  are  being 
marketed,  and  have  proved  the  contention  of  their  makers  that  they 
are  economical  in  operation  and  maintenance. 

Four-Wheel  Steering  Arrangement.  With  the  design  shown  at 
Fig.  348,  steering  knuckles  are  eliminated,  the  wheeb  being  con- 


FIc,  346.     DetoilB  of  Aile  of  the  Faui-Wh«l  Drive  Truck  Sbown  in  Fi«.  348. 

nected  to  the  axle  ends  through  the  medium  of  vertical  trunnions. 
These  trunnions  bear  on  the  wheel  ball-bearing  ring,  which  is  ample 
in  diameter  and  turns  freely  because  of  its  size  and  lV\&  Ma&  o\  \i^ 


m 


GASOLINE  AUTOMOBILES 


bearings.  Within  tliis  ring,  the  axle  terminates  in  what  is  practically 
a  universal  joint,  driving  through  to  the  outside  of  the  wheels.  The 
wheels  are  thus  free  to  run  about  a  point  in  the  axle  ends,  at  the  same 
time  taking  their  power  through  the  inside  rotating  shaft.  Fig.  349 
illustrates  one  of  these  axles  with  the  parts  lettered.  Here  7/  is  the 
point  of  attachment  of  the  driving  propeller  shaft,  G  the  cast-steel 
onc'-piete  case,  F  the  diflerential  gear  within  the  large  driven  bevel 
gear  0,  MM  the  vertical  trunnions  upon  which  the  wheels  rotate,  and 
N N  tile  univLTsal  joints  which  drive  the  wheels. 

Hiiw  the  steering  is  obtained  is  shown  in  Fig.  350.  At  the  front 
of  the  chassis  is  the  steering  wheel  P;  turning  it  partially  rotates  the 
longitudinal  shaft  Q,  which  extends  the  length  of  the  chassis.  This 
shaft  carries  Icvpfs  RR   near  its  two  ends,  which  are  connected  to 


'■ ^fcH^—i ^^ 


GASOLINE  AUTOMOBIUa 


distance  or  time  of  the  ordmary 
truck.  Four-wheel  steering  then 
has  the  advantage  over  two- 
wheel,  or  OTdinary,  steering,  of 
requiring  only  one-half  the  space 
and  one-half  the  time  to  accom- 
plish a  given  turn.  The  vehicle 
described  would  turn  completely 
around  in  a  circle  of  40  feet,  the 
outermost  circle  shown  in  Fig. 
350  being  56  feet  in  diameter. 

Chain  Four-Wheel  Drive. 
Fig.  351  clearly  illustrates  a  bot- 
tom view  of  the  Hoadley  four- 
wheel  drive,  four-wheel  steer,  and 
four-wheel  brake  truck.  The  . 
power  of  the  engine  is  trans- 
mitted through  shafts,  gears,  and 
universal  joints  to  the  differen- 
tials; there  is  a  third  differential 
in  the  gear  box  at  the  center  of 
the  frame.  Final  drive  is  by 
chain ;  both  ends  of  the  truck  are 
exactly  alike  in  so  far  as  the  four- 
wheel  drive  is  concerned,  and  the 
fifth  wheels  run  in  ballbearings. 
Steering  is  accomplished  by  means 
of  worm  gearing,  the  shaft  being 
clearly  shown,  and  both  seta  of 
wheels  are  steered  simultaneously. 
Jeffery  Quad.  An  example 
.  of  the  successful  development  of 
the  four-wheel  drive  is  the  Jeffery 
Quad,  Fig.  352,  which  has  given 
an  excellent  account  of  itself  in 
government  work.  In  this  type 
it  will  be  noted  that  the  inclined 
driving  shafts,  shown  in  Fig.  348, 


- 6  suuiis  TO  me  ironc  a 

tion  of  each  other,  are  set  off  to  th 
by  making  the  transmistiion  verj 
as  shown  in  Fig.  353.  Tlie  engim 
are  gears  that  transmit  the  rotatio 
through  the  final  gears  E  and  F,  d 


ports,  B  driving  one  pair  of  wheels, 
that  the  differential  has  been  inc 
so  that  it  is  possible  to  have  a  di 
from  that  for  the  rear  wheels. 
Th«  r«*  "»  -' 


GASOUNE  AUTOMOBILES 


487 


section  is  fixed  a  small  box  which  contains  the  bevel  gears  and  an 
additional  differential  with  suitable  bearings,  the  whole  being 
enclosed.    These  can  be  seen  in  Fig.  352,  that  on  the  rear  axle  being 


Hlulta  tor  Roth  AiIm 


plainly  shown,  while  the  one  in  front  is  part1>'  obscured.  This 
member  is  shown  in  detail  in  Fig.  354,  which  gives  the  longitudinal 
section  along  the  driving  shaft  at  the  left,  in  which  the  axle  //  is 
noted,  the  bevel  gear  /,  and  the  bearings  for  radial  and  thrust  loads 


F^.  354.     Bcdjoi 


Ai]»  OD  Jcflery  Quwl 


at  J  and  A',  respectively.  The  driven  shaft  is  seen  at  L,  with  the 
sleeve  M  around  it,  the  sleeve  being  used  to  drive  to  the  difTercntial 
case,  since  the  larger,  or  driven,  bevel  C  is  not  suSiewnl\^  Wx%«.\n 
bouse  the  differentia}  /*. 


GASOLINE  AUTOMOBILES 


Fig.  355  is  a  fiiaf,'rani  showing  the  details  of  the  axle  end  and 
wlieel  constnictifiii.  In  this,  //  is  the  I-beam  section  of  the  axle  bed 
shoim  in  Fig.  ^52.  ami  X  one  of  the  shafts,  which  carries  at  its 
end  the  universal  joint  Q,  with  the  end  of  the  shaft  extending  beyond 
the  joint  R.    Thp  latter  carries  the  spur  gear  S,  which  mealies  with 


GASOLINE  AUTOMOBILES  489 

turns  the  wheel  is  attached  at  X,  the  pair  (either  both  front  or  both 
rear  wheels)  being  connected  by  means  of  a  cross-rod;  at  one  end  of 
this  rod  there  is  a  connection  to  a  rod  which  runs  the  entire  length 
of  the  chassis.  This  rod  is  operated  by  means  of  the  steering  gear, 
and  imparts  the  same  motion  to  the  front  wheels  as  to  the  rear, 
except  that  the  two  are  in  opposite  directions,  that  is,  front  wheels 
turn  to  the  left  and  rear  wheels  to  the  right,  so  that  they  will  follow 
around  in  a  correct  circle. 

Aihardages  of  Four-Wheel  Drwe.  It  is  claimed  for  the  four-wheel 
drive  that  its  four-wheel  steering  reduces  the  mileage  traveled  to  the 
minimum  in  that  the  car  can  run  closely  to  corners  and  travels  less  in 
crowded  traffic,  in  turning  around,  and  in  approaching  and  leaving 
loading  platforms.  The  push  of  the  rear  wheels  and  pull  of  the  front 
wheels  enables  it  to  surmount  obstacles  instead  of  bumping  over 
them,  and  its  greater  traction  permits  it  to  travel  soft  roads  not 
easily  negotiated  by  the  rear-drive  tjpe  of  trucks  and  cars.  The 
four-wheel  drive  type  will  turn  in  a  48-foot  circle,  and,  with  its  lock- 
ing differential,  obtains  traction  on  slippery  roads. 

Electric  Drive.  When  the  final  drive  is  electric,  or  when  the 
source  of  power  is  an  electric  motor,  the  matter  of  four-wheel  driving 
13  much  simphfied,  the  wheel  carrying  the  electric  motor  attached 
directly  to  it  and  turning  with  it  about  the  knuckle  pin.  Both 
wheel  and  motor  are  turned  by  means  of  a  worm  and  gear  above,  the 
wheel  being  attached  to  the  upper  end  of  the  steering-knuckle  pin 
prolonged.     Turning  thisturns  the  wheel  and  motor. 

This  steering  wheel  is  turned  by  the  worm,  which  is  on  one  end 
of  a  cross-shaft.  This  shaft  is  carried  in  bearings  above  the  stationary 
bed  of  the  axle  and  has  near  the  center  a  bevel  gear  that  meshes 
with  another  bevel,  which  is,  in  turn,  attached  to  the  lower  end  of  the 
steering  post.  Turning  the  steering  wheel  turns  the  post  and  the 
bevel  gear,  which  turns  the  bevel  pinion  and  with  it  the  worm  shaft. 
The  shaft  turns  the  worm  and  the  worm  wheel  which  actuates  the 
road  wheels.  The  driver  thus  has  a  triple  reduction  between  himself 
and  the  wheels,  giving  him  this  much  advantage  in  steering:  there  is 
the  leverage  of  the  wheel  of  large  diameter;  the  ratio  of  the  sizes  of 
the  two  bevels,  and  the  ratio  of  reduction  of  the  worm  gearing,  which, 
in  addition,  is  irreversible.  The  steering  gear  is  thus  eliminated  and 
four  umple  gears  substituted  for  it. 


h: 

m                       GASOLINE  AUTOMOBILES                                | 

Coiiple-fimr    Ti/pr.     In   the   Couple-Gear   wheel,  which   is  an 
American  prufiuct,  tlie  Tiiutor  is  placed  inside  of  the  wheel — a  type 
e.spetiall>'  designed  and   construeted   for  this  purpose.     With   the 
motor  in   this  position,   the  wires  enter  through  the  hollow  hub, 
altering  its  ciinstruction  very  materially.     As  compared  with  the 
electric  motor  on  each  wheel,  previously  described,  this  form  has  the 
idvaiitage  of  greater  simplicity,  fewer  parts,  superior  appearance, 
and  protection  against  the  elements,  while  the  enclosed  position  of  the 
notor,  Axhich  is  the  most  delicate  part  of  the  machine,  protects  it 
against  road   oljstructiima  and  accidents.     This  arrangement  also 
simnlifies     the     stperinif 

i 

f 

hs 

problem,  since  the  car  is 
steered  just  the  same  83 
any  other   truck,   much 
of  the  complication  inci- 
dent to  an  electric  motor 
on  each  wheel  being  elim- 
inated. 

Fig.  356  is  a  view  of 
the  whee]  with  the  tire 

^1 

GASOLINE  AUTOMOBILES 


491 


In  the  second  illustration,  Fig.  357,  an  axle,  either  front  or  rear, 
with  the  wheels  removed,  is  presented.  In  this  cut  the  left  wheel  is 
entirely  removed,  but  the  one  on  the  right  shows  the  axle  spindle  B, 
the  method  of  fixing  it  in  the  axle  support  at  C;  the  armature  housing 
D  is  no^ally  within  the  wheel  arid  not  visible.  One  feature  peculiar 
to  this  arrangement  is  the  steering,  which  is  effected  by  means  of 
a  vertical  post  with  a  small  spur  gear  at  its  lower  end  E.  This 
meshes  with  a  curved  rack  F,  which  is  machined  on  the  outside  of 
a  pivoted  member  G,  fo  which  a  pair  of  arms  are  attached.  One  of 
these  arms  H  has  a  rod  /,  which  runs  to  and  operates  the  right-hand 
spindle  B,  while  the  other  J  has  a  similar  rod  A',  which  operates  the 
left-hand  wheel.  When  all  four  wheels  are  to  be  driven  in  this 
manner,  the  post  is  vertical,  but  the  connection  with  the  rack  F 


becomes  horizontal,  with  a  continuation  to  the  rear  axle  which 
operates  the  various  arms,  levers,  and  rods  there  in  the  same  manner. 
This  particular  system  is  used  for  heavy  commercial  work  only, 
and  in  this  it  has  been  particularly  successful  as  a  tractor,  a  front  axle 
and  a  pair  of  wheels  being  substituted  for  those  of  a  heavy  trucking 
wagon.  Then,  with  a  sling  under  the  body  or  beneath  the  driver's  seat 
for  the  batteries,  and  with  proper  wiring,  control  levers,  and  steering 
wheel,  the  truck  becomes  electrically  driven. 

FRONT  AXLES 
TYPES 
Classification.     Generally  speaking,  front  axles  may  be  divided 
into  about  five  classes:  the  Elliott,  the  so-called  reversed  Elliott,  the 
Lemoine,  the  front-drive  form,  and  the  fifth-wheel  form. 


492  GASOLINE  AUTOMOBILES 

These  tj^pical  forms  of  axles  are  themselves  subject  to  further 
subdivisions.  For  example,  there  are  maay  different  forms  of  Elliott 
axles,  each  manufaeturer  having  what  is  practically  hia  own  form. 
Again,  the  Lemoiiie,  when  used  by  other  firms,  has  been  built  in  a 
practically  new  form,  taking  the  second  maker's  name.  Thus  the 
fomi  of  front  axle  made  by  Lemoine  for  Panhard  is  so  different  as  to 
be  called  the  Panhard,  and  not  the  Lemoine.  The  same  is  true  of 
the  Lisses  axle  made  by  Lemoine.  In  this  country,  it  is  claimed 
that  tlie  axles  made  1),\-  Timken  are  sufficiently  different  from  the 
Elliott  anil  reversed  P^Iliott,  from  which  the  principle  was  taken,  as  to 
deserve  the  name  of  Timken  axles.  It  should  be  borne  in  mind  that 
in  the  following  descri|)tion  of  the  various  axle  types  the  forms  nf 
material,  ami  the  sliape,  sii!e,  and  kinds  of  bearings  used  do  not  alter 


GASOLINE  AUTOMOBILES 


forms  a  straight  vertical  cylindiical  portion  bored  for  the  pivot  pin, 
:  while  the  knuckles  are  so  formed  as  to  have  jaw  ends  which  go  over 
c  the  axle  ends.  The  thrust  comes  at  the  bottom  of  the  knuckle, 
where  the  axle  bed  rests  upon  the  upper  face  of  the  lower  jaw  of  the 
I  knuckle,  the  axle  representing  the  load  and  the  knuckle  the  support, 
:  just  the  reverse  of  the  previous  case. 

T^his  will,  perhaps,  be  made  clearer  by  illustrations.    In  Fig, 

"  358,  as  already  mentioned,  the  axle  has  the  jaw  ends,  and  the  thrust 

comes  at  the  top.     This  is  indicated  in  the  figure  by  the  letter  A, 

which  calls  attention  to  the  thrust  washers  at  the  top.     Fig.  359 

shows  an  axle  of  the  reversed  Elliott  tj-pe,  this  being  the  front  axle 


"^^n 


Fj«.  3S0,     Revenied  Elliot  Type  of  Frool 


Steerinc  Knucklo 


for  a  heavy  truck.  In  this  the  thrust  washers  A  are  at  the  bottom, 
and  are  of  hardened  steel,  ground  top  and  bottom  to  a  true  surface; 
the  upper  surface  is  doweled  to  the  axle,  while  the  lower  is  doweled 
to  the  knuckle.  This  form  has  the  real  advantage  of  concentrating 
all  of  the  difficult  machine  work  and  assembling  it  into  one  piece, 
the  knuckle.  The  Elliott  type,  on  the  contrary,  makes  the  knuckle 
and  axle  difficult  pieces  to  handle  in  the  machine  and  afterward,  this 
being  shown  in  the  cost.  Ease  of  machining  the  bed  of  the  axle 
is  a  great  advantage,  for  the  axle  will  average  about  44  inches  in 
length  for  a  standard  tread  of  66}  inches,  and  longer  for  wider  treads, 
up  to  a  maximum  of  about  4S  inches  for  the  wide-tread  standard  in 
the  South. 


v^  iiuiu  and  machine  these  pt 
than  an  axle  of  cnrrespondin^ 
Lemoine  Type.  The  I>t 
those  described  in  that  the  ax 
of  the  knuckle-pin  part  of  the 
that  is,  an  extension  or  a  jaw  o 


With  this  design,  the  thrust  loud 
upon  the  knuckle,  whicli  also  m 
in  a  sidewise  direction  at  but  one 
side  shocks  are  taken  on  the  en 
end,  whereas  with  the  other  ty( 
two  supports,  or  divided  ivi—"-- 


m   ir     ^^^^^^^^H 


GA80UNE  AUTOMOBILES 


Interted  Lemmne.  A  novel  type  of  axle  has  been  created  in  the 
1916  Overland  car,  Model  75,  called  an  inverted  Lemoine.  In 
this  type,  as  Fig.  360  shows,  the  wheel  spindle,  or  stub  axle,  is  at 
the  top  of  the  steering  knuckle  instead  of  at  the  bottom  as  in  the 
case  of  the  regular  Lemoine  type.  The  knuckle  has  a  single,  fairly 
long  support  in  the  end  of  the  I-beam  front  axle,  the  foiling  being 
much  simpler  on  this  account.  In  fact,  this  makes  the  axle  nearly 
straight,  which  doubtless  accounts  in  large  part  for  this  unusual 
design.  One  real  advantage  of  this  design  is  that  It  allows  the  car 
weight  to  be  low  in  relation  to  wheel  bearings,  thus  assisting  in  steering. 


Marmon  Self-Lubricating  Axle.  The  new  Marmon  front  axle. 
Fig.  361,  is  of  the  inverted  Lemoine  type  similar  to  the  Overland, . 
shown  in  Fig.  360,  but  at  first  glance  it  looks  quite  different.  For 
one  thing,  the  bearing  in  the  axle  end  is  different,  and  in  this 
lies  an  exclusive  and  valuable  feature.  The  stub-axle  pivot  pin, 
made  integral  with  the  stub  axle,  is  placed  in  a  split  bushing,  which 
is  a  tightfit  at  the  bottom — where  the  thrust  collars  are  formed  in  it — 
and  at  the  top,  but  not  in  the  middle.  When  this  bushing  is  in  place, 
the  knuckle  and  bushing  are  forced  into  the  axle  end  from  above, 
and  a  kind  of  hub  cap  screwed  on  at  the  bottom.  This  holds  it 
permanently  in  place. 


n(.  3&Z.    Front  Elevtticn  d  C*t,  B 


Like  the  Ch-erland,  this  arw"- 


GASOLINE  AUTOMOBILES      -  497 

and  most  all  pavements  are  made  with  a  camber.  The  center  of  the 
road  is  made  higher  than  the  sides  so  that  the  road  will  drain.  It 
is  necessary,  in  order  to  have  the  lower  spokes  plumb  or  perpendicular 
to  the  road  surface,  to  throw  the  center  line  of  the  wheel  out  of  the 
vertical  plane  2  or  3  degrees.  This  otTset  is  also  called  camber,  and 
it  complicates  the  construction  of  the  axle  ends  to  such  an  extent 
that  they  must  be  machined  with  this  slight  angle  either  in  the 
knuckle  or  in  the  axle,  or  distributed  over  the  two  places. 

Fig.  362  shows  the  effect  of  this  camber  upon  the  front  appear- 
ance of  the  car,  the  slight  angle  of  the  front  wheels  giving  the  car  a 
bow-legged  appearance. 

Gather  Further  Complicates  Axles.  What  the  carriage  men 
term  "gather"  further  complicates  the  axle  ends.  This  is  the  practice 
of  setting  the  axle  so  that  the  front  wheels  are  closer  together  at 
the  front  than  at  the  rear,  that  is,  they  toe  in.  The  idea  of  tliis  is 
to  make  steering  easier  and,  more  particularly,  to  make  the  car 
self-steering  on  plain,  level,  straight-ahead  roads.  It  is  scarcely 
noticeable  from  in  front,  but  is  from  above.  Although  many  cars 
still  have  it,  it  is  not  used  as  much  now  as  formerly. 

MATERIALS 

The  materials  utilized  for  front  axles  include  castings  of  steel, 
manganese  bronze,  iron,  and  other  metals,  in  the  form  of  forgiiigs, 
drop  forgings,  drawn  or  rolled  shapes,  and  pressed  shapes.  Wood 
has  been  but  little  used  and  only  in  the  past. 

Cast  Axles.  Castings  for  front  axles  have  been  looked  upon 
with  grave  doubt  and  fear  by  designers  and  owners,  because  of 
the  fact  that  road  shocks  are  more  severe  for  front  than  for  rear 
axles,  and  because  of  the  fear  that  a  casting  may  have  a  blowhole 
or  some  other  defect.  In  addition  to  the  natural  distrust  of  castings 
for  this  work,  it  was  feared  that  such  material  would  crj'stallize  more 
quickly  than  would  a  better  and  more  homogeneous  material  like 
steel.  There  is,  of  course,  a  certain  amount  of  crystallization  in  all 
materials,  but  far  less  in  a  close-grained  fine-fibered  structure  like 
forged  or  rolled  steel  than  in  any  form  of  casting.  Aside  from  this, 
castings  present  many  other  advantages  which  are  well  worth  while. 
Thus,  the  spring  pads  may  be  cast  int^ral  with  the  axle  with  prac- 
tically no  extra  charge,  while  the  same  forged  integral  with  a  droy- 


.^.^  i.ao  mxn  ana  IS  aistrus 

it  have  flown  in  the  face  of  po) 
mistrusted  it  even  more  than  the 
ing  has  been  little  use<1,  and  tht 
with  a  cast  axle  now  on  the  mark 
Fitfgings.     Forgings,  as  disti 
much  used  for  good  front  axles,  but 
of  one  excellent  truck  builder,  stri 
world,  who  is  using  a  hand-forgei 
shown  in  Fig.  359.     It  is  forged  d' 
steel  and  the  ends  worked  out  so  a: 
2J-inch  section,  which  later  has  bt 
This  made  a  very  costly  piece  of 
shown  in  actual  work  more  than  mai 
be  found  to  pay  the  price  demanded 
Many  smaller  makers  follow  c 
work  allowing  the  axles  to  be  forgi 
easily,  and  more  cheaply.    The  sn 
be  heated,  the  less  difEcult  will  be 
will  progress  be  made.     The  genci 
however,  is  to  turn  o\'er  the  axle  jo 
of  whom  employ  drop  forgings,  dr 
dron-fn"-""*  — -■- 


GASOLINE  AUTOMOBILES 


the  method  itself  produces  better  quality,  for  any  process  which 
works  steel  or  wrought  iron  over  and  over  again  improves  its  quality, 
provided  the  steel  is  not  burned  in  the  process  of  heating.  Not  only 
are  the  majority  of  axles  made  of  drop  forgings,  but  of  those  not  so 
made  some  part  is  almost  sure  to  be  a  drop  forging,  as,  for  example, 
those  made  of  steel  tubing  which  have  their  ends  or  other  parts 
made  by  the  dropHforging  process.  In  Fig.  363  is  shown  a  drop- 
forged  axle  used  on  a  truck. 

Tubular  Axles.  The  I-beam  section  of  front  axle  is  universally 
used,  and  while  the  tubular  tj-pe  formerly  enjoyed  some  popularity, 
its  use  today  is  confined  to  a  very  few  vehicles.  When  employed, 
its  ends  are  drop  forged  or  drawn,  or  rolled  steel  may  be  used 
with  the  ends  welded  or  otherwise  secured.  The  disadvantage  of 
the  tubular  type  is  the  fastening  of  the  ends  which  is  more  or  less 
offset  by  the  lowered  cost  of  material. 


Kg.  3S3.    TVpiml  Drop-Forged  Aile  U«ed  on  Truck 

Drop-Forged  Ends.  Nearly  ail  the  ends  for  axles  made  in  this 
way  are  drop  forgings,  very  few  castings  being  used,  while  the  spring 
pads,  or  spring  seats,  as  they  are  sometimes  called,  are  split  into 
upper  and  lower  halves  and  bolted  on. 

The  loading  conditions  of  all  front  axles  are  such  that  the  load 
rests  on  the  axle  at  two  points  inside  of  the  supporting  points — 
the  wheels.  Thus,  tlie  continual  tendency  of  the  load  acting  down- 
ward and  of  road  shocks  acting  upward  is  to  bend  the  center  of 
the  axle  still  further  downward.  Since  a  tube  which  has  been  bent 
once  has  been  weakened,  it  follows  that  this  tendency  to  weaken  it 
presents  a  further  source  of  trouble. 

Pressed-Steel  Axles.    The  pressed-steel  type  of  axle,  which 
made  its  initial  appearance  in  1909,  and  is  not  genen^'^  eov^^'o^c^, 
consisted  of  a  pair  of  pressed-steel  channel  duw\iea — o'ca  Nwiv"^ 


soo 


GASOLINE  AUTOMOBILES 


slightly  larger  than  the  other — set  together  with  the  fiaoges 
inward  so  as  to  present  a  box-like  shape.  When  thus  arranged,  the 
two  sections  were  riveted  together  by  a  series  of  rivets  running  ver- 
tically along  the  center  part  of  the  channels.  The  ends  eon-iist  of 
drop  forgings,  machined  to  size  or  Space  between  the  channels  when 
assemhled,  and  then  .set  into  place  lietween  the  ends  and  riveted. 
The  presscd-stcel  construction  obtained  a  secure  attachment  to  the 
JK-d.     This  iixli-  was  of  tiie  Elliott  reversed  type. 

Change  of  Axle  Type  Simplifies.  Often  the  change  from  one 
type  of  a\le  to  rhc  otlier  is  not  made  Iwcause  the  latter  is  better  but 
hecanse  of  some  iiicirlfntal  saving  in  the  manufacture.     Thus,  in 


GASOLINE  AUTOMOBILES 


AXLE  BEARINGS 


Classification.  Thus  far  nothing  specific  has  been  said  about 
axle  bearings.  These  are,  according  to  construction,  of  three  kinds; 
plain,  roller,  and  ball.  From  the  standpoint  of  the  duty  which 
they  are  to  perform,  bearings  may  be  divided  into  radial-toad  and 
thrust  bearings,  all  three  forms  mentioned  above  being  used  for 
both  purposes,  but  arranged  differently  on  account  of  the  difference 
in  the  work.  Each  one  of  the  three  classes  may  be  further  subdivided. 
Thus,  plain  bearings  may  be  of  bearing  metal  or  of  hardened  steel, 
or  they  may  even  be  so  constructed  as  to  be  self-lubricating.  Again, 
plain  bearings  may  mean  no  bearings  at  all  as  in  the  old  carriage 
days  when  the  axle  passed  through  a  hole  in  the  hubs,  and  whatever 
wear  occurred  was  distributed  over  the  inside  of  the  hubs,  resulting 


after  a  time  in  the  necessity  for  either  a  new  set  of  hubs  or  a  new  axle, 
or  for  the  resetting  of  the  axle,  so  that  the  hubs  set  furtlrer  up  on  a 
taper.  Roller  bearings  may  be  of  several  classes,  some  makers  using 
both  straight  and  tapered  rollers.  In  addition  to  these  there  are 
combinations  of  the  straight  and  tapered  types,  and  bearings  with 
two  sets  of  tapered  rollers  acting  back  to  back,  the  action  being  that 
of  straight  rollers,  with  the  end-adjustment  feature  of  the  tapered 
type.  There  are  also  many  types  of  ball  bearings,  as,  for  example, 
plain  ball  bearings — those  working  in  flat  races,  those  working  in 
curved  races,  those  working  in  V-^rooved  races,  and  single  twUa 
working  aiooe.    Here  are  also  combinations  of  ba)\a  m.  ^q>9^«  to«%. 


302  GASOLINE  AUTOMOBILES 

Roller  Bearings.  Fij;.  359  shows  the  use  of  tapered  roller  bear- 
ings for  the  hubs  and  of  hardened-steel  thrust  washers  for  the  thrust 
toad,  the  figure  showing,  in  addition,  a  plain  brass  bushing  in  the 

•  axle  for  the  knuckle  pin  to  turn  in.  In  Fig.  3fi5  is  shown  a  more 
elaborate  use  of  roller  bearings  of  very  excellentdesign.  In  addition 
to  the  axle  bearing,  it  will  be  noted  that  the  top  bearing  of  the  steer- 
ing knuckle  is  of  the  roller  type. 

Bali  Bearings.  Although  there  is  a  growing  tendency  to  utilize  a 
short  adjustable  tjpe  of  roller  bearing,  mani'  designers  favor  the  bull 

-  bearing.  The  two  most  common  forms  are  the  cup  and  cone  type, 
which  cares  for  radial  and  thrust  loads,  and  the  annular  form  which 


GASOUNE  AUTOMOBILES 


503 


radial  loads.  At  the  top  is  tinother  ball  bearing  arranged  for 
thrust;  this  bearing  taking  up  all  thrust  loads  from  the  weight  above 
or  from  road  inequalities.  Fig.  367  illustrates  the  cup  and  cone  type, 
This  design  utilizes  ball  bearings  for  the  hubs  and  plain  steel  thrust 
washers  on  the  knuckle. 

FRONT  AXLE  TROUBLES  AND  REPAIRS 
Alignment  of  Front  Wheels  Troublesome.    The  lack  of  align- 
ment of  front  wheels  gives  as  much  trouble  as  anything  else  in  the 


front  unit.  This  lack  not  only  makes  steering  difficult,  inaccurate 
and  uncertain,  but  it  also  influences  tire  wear  to  a  tremendous  extent. 
As  Fig.  368  indicates,  even  if  the  rear  axle  should  be  true  with  the 
frame,  at  right  angles  to  the  driving  shaft,  and  correctly  placed 
crosswise — correct  in  every  particular  with  the  shafts  both  straight 
so  that  the  wheels  must  run  true — the  fronts  may  be  out  with 
respect  to  the  frame,  out  of  track  with  the  rears,  or  out  with 
respect  to  each  other. 

In  order  to  know  about  the  front  wheels,  they  should  be  mea.%- 
ured;  while  tihis  sounds  simple,  it  is  anything  Wl  tVisA..    \ti.  ^Ifte  ^srS<. 


fi(M 


GASOLINE  AUTOMOBILES 


place  there  is  little  to  Dieasure  from  or  with.  A  good  starting  place 
is  the  tires,  and  a  simple  measuring  instrument  ts  the  one  shovm  in 
Fig.  369.  This  instrument  consists  of  a  rod  ahout  1  inch  in  diameter 
and  about  3  feet  long,  fitted  into  a  piece  of  pipe  about  2  feet  long, 
with  a  square  outer  end  on  each,  and  a  set  screw  to  hold  the  mcAii- 
urements  as  ohtaine<I.  By  placing  this  rod  between  the  oppoate 
sides  of  the  front  tires,  it  can  be  ascertained  whether  these  are  par- 


riK    :UiH.     DinnTun,  ahoinn*  Froni 


GASOLINE  AUTOMOBILES 


505 


with  the  frame  Unes,  and  whether  the  wheels  are  perfectly  parallel. 
Given  the  frame  line,  too,  it  can  be  determined  whether  the  wheels 
track  with  one  another. 

Straii^tening  an  Axle.  When  an  axle  is  bent,  as  in  a  collision, 
a  template  is  useful  in  straightening  it.  This  can  be  cut  from  a 
thin  sheet  of  metal,  light  board,  or  heavy  cardboard.     It  is  an  approx- 


Flf.  370,     AccuTBte 


Better  Dwcn  than 


imation  at  best  and  should  be  used  with  great  care.    Fig.  371  shows 
such  a  template  applied  to  an  axle  which  needs  straightening. 

When  the  axle  is  bent  back  to  its  original  position,  a  pair  of 
straightedges  laid  on  top  of  the  spring  pads  will  be  of  great  assistance 
in  getting  the  springs  parallel,  as  the  worker  can  look  across  the 
straightedges  with  considerable  accuracy.    This  is  indicated  in  the 


Pic.  371.     TemplxU  tot  8lwwin(  i[  Aile  Ii  Bent 

first  part  of  Fig.  372,  which  shows  the  general  scheme.  It  shows  also 
how  the  axle  ends  are  aligned,  using  a  large  square  on  top  of  a 
parallel  bar,  but  of  course  this  cannot  be  done  until  the  last  thing, 
at  least  not  until  the  spring  pads  are  made  parallel. 

Front  axles  of  light  cars  may  be  straightened  without  removal, 
provided  the  bend  ia  not  in  the  nature  of  a  twist  and  not  too  eiunl. 
Take  two  iiardtTOod  p/ants  /feetlong,  1.0  u^cVeawAie.MA'i'vM^Ma 


GASOLINE  AUTOMOBILES 


thick.  Next,  cut  four  ^-im-h  blocks  10  inches  long  and  '.i  inches  wide. 
Lay  the  blocks  flat  between  the  planks,  space  tliem  iilwiit  2  fret  apart, 
and  bolt  the  whole  securely.  This  obtains  a  girder  7  feet  long,  10 
inches  wide,  and  4|  inches  thick.  Next,  take  two  pieces  ()r  4  X  4  limber 
3  feet  long  and  cut  a  tenon  on  one  end  of  each.  Make  three  J-inch 
eye  bolts,  12  inches  long,  with  nuts  and  plate  washers  for  each.  Place 
one  of  the  eye  bolts  between  eadi  pair  of  bl(]cks  and  screw  up  the  nuts 
and  washers  sufficiently  so  as  to  rivet  them.  This  permits  of  moving 
the  eye  bolts  to  any  position  between  the  blocks.  Two  small  steamboat 
ratchets  and  several  short  but  strong  chains  complete  the  equipment. 


GASOLINE  AUTOMOBILES 


507 


For  example,  a  downward  bend  can  be  straightened  by  placing  the  car 
above  the  girder,  connecting  the  axle  to  the  girder,  and  using  a  short 
screw  jack  to  remove  the  bend.  This  device  can  be  used  with  success 
in  shops  dealing  with  light-  or  medium-weight  cars. 

Spindle  Troubles  and  Repairs.  Wear  of  the  spindle,  or  knuckle 
bolt,  and  its  bushings,  as  weUasplay  in  the  steering-gear  linkage,  brings 
about  wobbling  of  the  front  wheels  when  the  car  is  in  motion.  Some 
experienced  persons  mistake  wear  of  the  knuckle  and  the  bushings  for 
play  in  the  wheel  bearings,  and  attempt  to  remedy  the  trouble  by 
adjusting  the  bearings.  It  is  a  simple  matter  to  determine  the  com- 
ponent at  fault.  To  test  for  bearing  play,  drive  a  block  of  wood 
between  the  knuckle  and  the  axle,  then  grasp  the  wheel  at  the  top  and 


Fie.  373.     Use  of  Wedgo  to  Cure  a  Wobbling  Wheel 


bottom,  or  at  points  diametrically  opposite,  and  test  for  looseness. 
If  none  exists,  the  play  is  in  the  knuckle  pin  and  its  bushings.  The 
remedy  is  to  fit  new  bushings  and  new  knuckle  pins. 

Wobbling  Wheels.  Wobbling  of  the  front  road  wheels  is  gener- 
ally due  to  play  in  the  joints  of  the  steering  mechanism,  arid  it  is  not 
only  troublesome,  but  also  sets  up  undesirable  stresses  on  the  steering- 
gear  linkage.  This  flapping  of  the  wheels  may  be  present  with  the 
steering  gear  and  linkage  in  perfect  operating  condition,  and  similarly 
when  the  springs,  hangers,  etc.,  are  in  good  condition  and  the  proper 
toe  in,  or.  gather,  of  the  wheels  exist. 

When  the  wheels  wobble  it  may  be  assumed  that  the  front  s^rvxv^ 
have  so  settled  that  the  steering  pivots  are  not  c\\\\te  Net^XcsWot^  ^X!l\ 


508  GASOLINE  AUTOMOBILES 

aft,  particularly  with  reference  to  that  t^v-pe  of  pivots  which  do  not 
incline  outwards  and  where  the  wheels  are  canted  or  dished  to  briog 
their  points  of  ground  contact  in  line  with  the  pivots.  A  cure  for  this 
trouble  is  to  place  wedges  between  the  front  springs  and  spring  seata 
so  as  to  alter  the  angle  of  the  steering  pivots,  as  shown  in  Fig.  373. 
^letal  wedges  are  used,  about  J  inch  thick  at  the  large  end,  and 
tapered  toaknifc-likcedge.  The  wedge  is  placed  at  the  forward  end  of 
the  axle,  and  a  little  experimentation  will  give  the  results  desired. 
In  wedging,  as  few  wedges  should  be  used  as  is  necessary  to  obtain  the 
desired  result. 

CHASSIS  GROUP 

III  arriLiijjing  -.i  logii'al  presentation  of  the  numerous  components 
of  the  nmtor  vehicle,  the  cha.ssis  is  separated  from  the  body.  It 
includes  the  power  pliiiit  and  mechanism  utilized  in  transmitting  the 
energy  of  the  engine  t<i  the  road  wheels,  also  the  frame  and  suspen- 
sion, the  axles,  ete.  However,  only  frames,  springs,  and  shock 
absorbers  will  be  discussed  in  this  section,  as  the  other  parts  of  the 
chassis  havi-  been  treatetl. 

Characteristics  of  Parts.  Frames.  The  chassis  frame  practi- 
is  till'  fonnilatiiiii  of  a  motor  vehicle,  since  all  of  the  power 


GASOLINE  AUTOMOBILES  509 

Springs.  The  primary  function  of  the  spring  is  to  absorb  the 
•id  shocks  that  would  otherwise  be  communicated  to  the  mechanism 
d  passengers.  Considerable  progress  has  been  made  tn  the  past 
ar  toward  improving  springs,  and  not  only  are  they  better  pro- 
rtioned,  but  improved  material  and  methods  of  mounting  have,  to  a 
2at  extent,  eliminated  breakage.  The  leaf  type,  developed  by  the 
rse-drawn  carriage  industry,  is  the  form  miiversally  employed  on 
>tor  vehicles,  both  pleasure  and  commercial.  { 

A  review  of  the  1916  springs  for  cars  showed  that  the  three- 
.arter  and  seven-eighths  elliptic  spring  was  favored  by  46.5  per  cent 
the  makers,  while  some  form  of  cantilever  spring  was  second  with 
.7  per  cent  for  rear  suspension.  This  year  the  advocates  of  the 
ntilever  have  gained  many  new  recruits.  In  the  matter  of  front 
rings,  the  semi-elliptic  may  be  said  to  practically  monopolize  the 
Id.    The  coil  spring  is  a  thing  of  the  past. 

Shock  Absorbers.  The  fitting  of  shock  absorbers  as  standard 
uipment  is  not  as  noticeable  as  it  was  in  1916  and  the  year  previous. 
le  use  of  high-speed  engines  with  light  reciprocating  parts,  and  the 
iployment  of  high-grade  light  material  in  other  components  of  the 
assis,  together  with  better  springs,  ser\'es  to  absorb  shocks  created 
■  traversing  rough  roads.  A  few  makers  supply  shock  absorbers, 
it,  as  a  rule,  the  car  manufacturer  leaves  the  selection  to  the  pur- 
aser.  Many  different  types  of  shock  absorbers  are  marketed,  and 
e  is  made  of  varying  principles. 

FRAMES 

Qeneral  Characteristics.  When  the  automobile  was  first  intro- 
,ced,  comparatively  little  attention  was  paid  to  the  frame,  as  the 
tier  components  of  the  chassis,  such  as  the  power  plant,  gearset, 
les,  etc.,  were  held  to  be  of  greater  importance,  consequently  the 
ime  did  not  receive  the  consideration  it  should.  After  experiencing 
nsiderable  difficulty,  however,  due  to  accidents  and  other  failures 
lich  were  traced  directly  to  poor  frame  design,  the  automobile 
gineer  found  that  it  was  possible  to  build  a  frame  of  great  strength 
th  less  weight  than  the  troublesome  types.  This  statement  applies 
the  frame  of  the  commercial  car  as  well. 

The  improvement  in  frame  design  is  the  result  of  the  tendency  to 
ovide  perfect  alignment  of  the  powei  plant,  du\^,  wcA  ^ 


510  GASOLINE  AUT0M0BILK8 

making  use  of  what  Is  known  as  the  unit  power  plaiit  on  somi*  nwHlels, 
white  on  others,  particularly  of  the  lieavjep  type,  flexible  mountiDK 
of  the  units  has  been  resorted  to.  The  tendency  is  toward  the  use  of  h 
flexible  mounting  of  all  individual  units,  at  least  to  aome  degree,  in 
order  to  relieve  tliem  of  the  stresses  brought  about  by  frame  weaving 
when  the  road  wheels  mount  an  ol)Stac!€  on  the  road  surface. 

Classes  of  Frames.  The  most  prominent  types  of  frames,  dJvidoi 
according  to  their  use.  are  the  pressed-steel  frame,  the  structural 
frame,  and  the  structural  I-beam  frame;  the  latter  is  coiifiiifd  to  com- 
mercial cars,  '  These  classes  may  be  subdivided  according  to  the 
general  construction  and  material;  &s  well  tii  to  the  distribution  of 
the  chassis  units. 

The  material  employed  is  either  pressed  or  rolled  steel.  The 
wood  frame  or  combinations  of  wood  and  metal  frames  are  practically 
a  thing  of  the  past,  and  a  re  to  be  found,  with  one  or  two  exceptions,  on 
old  cars.  The  steel  frame  may  bt?  constnicteil  in  the  following  shapes: 
channel.  L-beam,  angle,  T,  Z,  tubing,  Hat  plates,  and  combinations 
of  any  two  or  more  of  these.  Other  forms  are  possible.  For  example, 
the  channel  may  be  turned  with  the  open  side  in  or  out,  the  two  coti- 
atructions  being  widely  different;  or  the  angle  may  have  the  comer 


GASOLINE  AUTOMOBILES 


511 


bent  upward  or  downward  at  the  ends  or  in  the  middle  really  differ 
from  those  frames  which  preserve  one  level  from  end  to  end.  The 
practice  of  bending  the  chassis  frame  is  very  prevalent  of  late, 
the  uptm*ning  of  the  ends  bringing  about  a  lower  center  of  gravity, 
making  for  stability  and  ease  of  entrance  and  exit  to  the  body. 

Tendency  in  Design.  There  is  a  marked  tendency  toward  mak- 
ing the  chassis  frame  wider  at  the  rear  and  narrower  at  the  front. 
In  one  or  two  cases  the  designer  appears  to  have  gone  to  the  extreme 
in  this  respect.  The  advantage  of  the  narrow  front  construction  is 
that  it  enables  the  car  to  be  turned  in  a  shorter  radius.  The  use  of  a 
wide  rear  frame  provides  more  space  to  support  a  wider  body.  A 
more  recent  development  is  to  make  the  longitudinal  bars  of  the  frame 
parallel  over  the  front  spring  and  near  the  rear  spring,  and  to  have 
them  tapered  from  behind  the  front  to  the  rear  springs.  A  certain 
amount  of  material  is  said  to  be  gained  by  this  construction,  as  no 
heavy  reinforcement  or  sudden  offset  is  necessary  to  the  frame.    By 


Fi^.  374.     Typical  Automobile  Frame  of  Pressed  Steel 

widening  the  frame  at  the  rear  it  makes  possible  the  placing  of 
the  springs  directly  underneath  the  frame.  Some  car  makers  have  the 
sides  of  the  frame  straight  over  the  entire  length,  but  tapered  from 
the  front  to  the  rear. 

Fig.  374  illustrates  what  is  termed  a  single  drop  or  a  kick-up. 
This  is  a  type  of  pressed-steel  construction,  of  channel  section,  and 
the  deepest  and  strongest  section  is  at  the  center  where  the  greatest 
stresses  occur.  Some  frames  are  built  with  a  double  drop,  having 
a  downward  bend  just  forward  of  the  entrance  to  the  rear  part  of  the 
car  body,  followed  by  an  upward  turn  just  back  of  the  same  entrance. 
The  upward  turn  at  the  back  is  carried  higher  than  the  main  part  of 
the  frame  for  the  purpose  of  obtaining  a  low  center  of  gravity.  Then 
there  is  what  is  termed  the  bottle-neck  construction,  a  bend  inward 
which  resembles  that  in  the  neck  of  a  bottle.  This  obtains  a  short 
turning  radius.  Originally,  frames  were  narrowed  in  front,  the  diStet- 
ence  in  the  width  between  the  front  and  rear  be\xv^  «X  fe:^\.  ^xi\»!^ 


S12 


GASOLINE  AUTOMOBILES 


or  so  on  each  side,  gradually  increasing  iintil  it  btcamc  5  and  6  inches. 
This  type  did  not  prove  efBcient,  and  the  trend  favoretl  the  tajwr 
previously  explained, 

A  not  uncommon  form  of  frame  is  show^l  in  Fig.  375.  which  pom- 
pensates  for  an  abnonnal  rise  of  the  rear  axle  without  the  possibility 
of  its  striking  the  frame.  Some  frames  have  a  bend  at  the  ends  to  take 
the  spring  fastenings. 

Pressed-Steel  Frames.  The  pressed-stecl  type  of  frame  is  verj- 
popular  with  designers  and  is  largely  used  on  commereial  cars  up  to 
and  including  1 -tun  capacity.  This  is  popular  because  it  is  the  lightest 
in  weight  for  equal  strength  of  the  structural  iron  or  niUetl  channel 
and  I-beam  section.     The  cost  of  pressed  steel  is  somewhat  higher. 


GASOLINE  AUTOMOBILES  513 

SubrFrames.  The  modern  tendency  is  lo  eliminate  the  sub- 
frame — a  step  due  to  the  flexible  mounting  of  the  power  plant  and 
unit  construction — because  it  simplifies  the  frame.  It  has  also  been 
made  easier  by  the  tapered  frame,  which  is  narrowest  at  the  front 
where  the  units  are  attached.  The  most  common  method  of  support- 
ing the  engine  is  the  three-point.  Sub-frames  are  used,  however,  as 
they  serve  the  purpose  both  of  supporting  some  unit  and  of  strength- 
ening the  frame.  j 

Sub-frames  may  be  of  two  kinds,  viz,  those  in  which  the  sub- 
frame  is  made  different  for  each  unit  to  be  supported,  and  others 
in  which  one  sub-frame  supports  all  units  regardless  of  size,  shape, 
or  character  of  work.  The  type  of  sub-frame  made  to  support  each 
unit  usually  works  out  to  two  pairs  of  cross-members,  one  for  the  front 
of  the  unit  and  one  for  the  rear;  while  the  type  which  supports  all 
units  regardless  of  size  works  out  to  longitudinal  members,  supported, 
in  turn,  by  two  cross-members,  front  and  rear.  The  added  weight  for 
the  first-mentioned  type  is  less  than  for  the  other,  since  it  comprises 
only  four  cross-members;  while  the  last-named  type  consists  of  two 
cross-members  equal  to  two  of  the  others  and  of  two  very  long  members 
parallel  to  the  main-frame  members,  each  much  longer  and  thus 
much  heavier  than  the  corresponding  cross-members.  In  the  two 
frames  already  shown,  Fig.  374  shows  the  unit  type  of  sub-frame  with 
only  cross-members,  while  Fig.  375  shows  the  more  modern  type  in 
which  the  power  plant  is  of  the  unit  type  and  rests  directly  upon  the 
main  frame,  being  the  three-point  suspension  type  in  which  the 
forward  point  is  on  a  frame  or  special  cross-member,  while  the  rear 
two  points  are  the  crankcase  supporting  arms  resting  directly  on  the 
main  frame. 

Rigid  Frame.  A  pressed-steel  or  rolled-stock  rigid  frame  has  its 
advantages,  particularly  with  reference  to  the  commercial  vehicle. 
It  permits  the  body  to  be  rigidly  secured  to  it,  and  as  it  does  not  give 
with  the  inequalities  of  the  road,  the  body  is  not  racked.  An  advan- 
tage of  the  rolled  stock  is  its  cheapness,  except,  of  course,  for  the 
lighter  models  of  the  assembled  type  for  which  frames  can  be  secured 
at  low  figures.  Another  advantage  of  the  rolled  stock  is  the  ease 
with  which  the  wheel  base  may  be  altered. 

Effect  on  Springs.  The  effect  of  frame  construction  upon  the 
design  and  duty  of  springs  should  be  consideTed.    TVx^  \^'aX.\»^ 


MBL 


GASOLINE  AUTOMOBILES  515 

is  not  generally  understood,  but  it  has  an  important  bearing  upon  the 
life  of  the  car.  A  rigid  frame  relies  upon  the  springs  to  allow  for  all 
axle  displacement.  If  a  front  and  a  rear  wheel  on  opposite  sides  are 
raised  several  inches  at  the  same  time,  the  frame  is  subjected  to  a 
torsional  stress.  If  the  frame  is  rigid,  springs  of  considerable  camber 
must  be  employed  in  order  to  absorb  the  shock  without  being  bent  past 
the  limit  of  safety,  and  they  must  be  suflBciently  flexible  to  absorb  all 
the  shock  without  any  tendency  to  lift  the  other  wheels  from  the 
ground.  To  accomplish  this  shock  absorption,  a  different  type  of 
spring  is  used  on  a  rigid  chassis  from  that  employed  on  a  flexible 
frame.  The  use  of  underslung  spring  suspension  has  come  into  favor 
for  this  reason,  as  it  permits  the  frame  to  be  carried  fairly  low,  without 
sacrificing  spring  camber  or  necessitating  a  dropped  rear  axle. 

The  flexible  frame,  when  diagonally  opposed  wheels  are  raised, 
does  not  impose  all  the  stresses  on  the  springs  but  it  absorbs 
a  part  of  them.  For  this  reason,  springs  on  a  flexible  chassis 
are  flat  or  nearly  so,  with  a  limited  amount  of  play.  Flexible  con- 
struction also  permits  the  frame  to  be  carried  equally  as  low  as  with 
the  imderslung  spring,  and  yet  the  spring  is  perched  above  the  axle, 
where  it  is  more  nearly  in  Une  with  the  center  of  gravity,  thus  reduc- 
ing side  sway. 

TYPES  OF  FRAMES 

Pressed  Steel.  Pressed  steel  is  purchased  in  sheet  form,  cut  to 
the  proper  shape  in  the  flat,  and  then  pressed  into  channel  form  under 
great  pressure.  It  is  made  of  steel  rolled  into  sheets  and  is  somewhat 
closer  grained  than  ordinary  steel.  There  is  no  breaking  of  the  flake 
in  the  rolling  process.  The  pressed-steel  frame,  as  previously  pointed 
out,  permits  of  greater  simplicity  in  assembling,  since  the  parts  can  be 
easily  bolted  or  riveted.  Fig.  376  is  of  the  type  of  pressed-steel  frame 
having  a  tapering  section,  a  kick-up  at  the  rear  end,  five  cross-members 
— one  of  them  a  tube — ^and  is  narrowed  in  at  the  front  to  give  the 
largest  steering  lock.    Otherwise  it  presents  only  standard  practice. 

Wood.    Wood  is  universal  and  easy  to  obtain.    While  no  longer 
classed  as  cheap,  it  is  not  expensive;  moreover,  wood  is  kept  in  stock 
nearly  everywhere.    Users  of  wood  for  side-frame  members  claim 
that  the  wood  frame  is  not  only  lighter  but  stronger.    Iiv  »ddvl\wv^ 
the  .wood  frame  would  undoubtedly  possess  more  xvatvit^  ^V^\sv%  ^"^^ 


SI6 

GASOLINE  AUTOMOBILES 

TABLE  IV 

Comparative  Strength  of  Steel  Channels  and  Laminated  Wood  PraraH 

1 

M.«,i., 

(in.) 

?^™i 

Pressed  Steel 
Ash 

Ax-lixl! 

13x6   . 

.408 
.26G 

114,830 

142,275 

2S0,9o5 

534,  sro 

resiliency,  so  that  if  would  make  a  lighter  and  easier  riding  frame. 

A  section  of  a  wood  frame  is  shown  in  fig.  377. 

This  shows  a  frame  made  of  laminated  wimxI.    There  are  three 

very  thin  sections  of  selected  ash,  marked  /I,  which  Bregluttl  together, 
then  screwed  and  bolted  to  pre- 
\ent  the  glue  from  opening  up. 
To  further  this  purpose,  a  strip  B 
IS  f,istt  nnJ  on  the  top  and  iMtttffD 
in  tht  same  manner.  These  strips 
are  laid  with  the  grain  running 
luinzuntally,  while  the  niatu 
pietes  are  laid  )\'ith  the  grain 
runnmg   vertically.     This    con- 


T^a 


i 


GASOLINE  AUTOMOBILES 


The  Fergus  car  was  developed  as 
a  result  of  fifteen  years'  experience  in 
fine  repair  work,  and  is  an  attempt  to 
eliminate  the  usual  "owner  troubles". 
While  not  intended  as  a  "foolproof" 
car,  the  Fergus  comes  nearer  being  one 
than  any  other  developed  up  to  this 
time.  In  addition  to  actually  "tooU 
proofing"  the  car,  the  aim  of  the 
makers  was  to  eliminate  much  of  the 
work  incident  to  caring  for  the  modem 
car  by  replacing  the  usual  "owner- 
attention"  with  an  automatic  system. 

In  the  frame,  a  combination  of 
steel  girder  and  lattice  work  has  been 
produced  which  has  the  appearance 
of  being  absurdly  light.  However,  as 
the  diagram  of  stresses  in  its  members. 
Fig.  378,  indicates,  everjihing  has  been 
figured  out  with  the  utmost  care,  and 
the  design  has  been  supplemented  by 
unusual  workmanship. 

The  complete  frame.  Figs.  379  and 
380,  shows  that  a  large  part  of  the 
saving  is  produced  by  the  method  of 
suspending  the  units^.  W^  these 
hung  on  the  side  members,  as  in  the  | 
ordinary  case,  the  frame  certainly 
would  not  do,  but  aa  it  is,  they  are 
hung  on  immensely  strong  brackets, 
steadied  by  the  side  members,  but 
rigidly  supported  by  large  tubular 
cross-members.  The  brackets  and 
cross-members  do  the  work  ordinarily 
assigned  to  the  side  members  of  the 
frame,  the  side  members  simply  joining 
and  holding  together  the  various  brack- 
ets and  cross-members. 


GASOLINE  AUTOMOBILES 


520 


GASOLINE  AUTOMOBILES 


varying  from  11^  to  16  inches,  serves  as  the  bottom  flange  of  the 
frame,  anf!  is  therefore  of  Z-section.  The  vertical  section  of  the  frame 
is  10  inches  high,  and  has  height  enough  to  replace  the  running  board 
fenders  wittiout  appearing  narrow.  At  the  front  and  rear  ends  of  tlie 
frame,  the  running  boards  are  curved  upward,  strengthening  the  frame 


as  well  as  suppiirtiiig  the  fenders  into  which  they  merge.  The  frame, 
beyond  these  points,  both  forward  and  rearward,  is  made  of  channel 
section  of  the  con^'cntional  type.  The  rear  of  the  frame  is  45  inches 
wide  and  tiipcri^  to  :iO  inches  at  the  front  spring  hangers.  The  great 
dfpth  of  till-  friinie  section  makes  it  very  stiff,  so  that  the  body  siils 


GASOLINE  AUTOMOBILES 


521 


Steel  Underpans.  The  underpan  has  assumed  a  great  deal  of 
importance  in  the  last  two  years,  for  makers  have  more  and  more 
realized  that  it  is  highly  important  to  protect  many  of  the  parts  from 
road  dirt,  flying  stones,  water,  etc.  '  Designers  have,  therefore,  given 


Fig.  383.     Two-Pieoe  Prewed-Steel  Underpan  Used  on  Winton  Cars 
Courtesy  of  WiiUon  Motor  Car  Company,  Cleteland,  Okie 

m 

considerable  attention  to  its  shape,  size,  and  method  of  attachment. 
In  some  types,  it  apparently  runs  underneath  both  engine  and  trans- 
mission and  is  made  more  or  less  a  part  of  the  main  frame.  There- 
fore, its  quick  removal  on  the  road  would  be  difficult,  if  not  impossible; 
yet  road  accidents  sometimes  make  it  necessary  for  the  driver  to  take 
this  pan  off  to  get  at  the  lower  side  of  engine,  clutch,  or  gear  box. 

For  this  reason,  underpans  generally  resemble  more  closely  that 
shown  in  Fig.  383.  This  is  a  side  view,  showing  the  semicircular 
form  of  the  pans,  as  well  as  the  two-piece  construction.  The  forward 
part  under  the  engine,  which  would  be  taken 
down  fairly  often,  is  held  in  place  by  three 
spring  clips  on  either  side.  Lifting  these 
clips  off  is  only  a  second's  work;  in  addition, 
there  is  a  filler  piece  in  front,  helping  to  make 
the  pan  fairly  air-tight.  The  depth  of  the 
pan  increases  slightly  toward  the  rear,  so  as 
to  form  a  slope  down  which  liquids,  will 
drain;  the  rear  end  is  fitted  with  an  upturned 
elbow,  so  that  it  will  not  drip  until  it  accu- 
mulates a  considerable  quantity  of  liquid. 
Continual  dripping  indicates  a  full  charge, 
and  the  pan  is  drained  by  turning  the  elbow 
over. 

In  Fig.  384,  a  detail  of  the  arrangement  of  the  pan  shown  in 
Fig.  383  is  presented.  This  indicates  both  the  permanent  part  of  the 
underpan,  which  is  attached  to  the  frame,  and  the  removable  part, 
which  is  freed  by  loosening  the  spring  clipa  aYvown. 


Fi«.  384.     Detail  of  Spring 

and  Section  of  Wintou 

Underpan 


GASOLINE  AUTOMOBILES 


523 


Commercial-Vehicle  Construction.  Commercial  work,  being 
rougher,  harder,  and  cheaper  work,  changes  the  frame  construction 
just  as  it  does  everything  else  about  the  car.  In  Fig.  385,  a 
commercial-vehicle  frame  which  brings  out  this  point  is  ^own. 
The  main  sills  are  6-inch  channels,  while  all  of  the  other  members 
are  correspondingly  large  angles  and  channels.  In  one  place  the  section 
consists  of  a  box  shape  made  up  by  bolting  two  large  channels  together, 
with  the  open  sides  in.  The  total  overall  length  is  not  given,  since 
this  differs  according  to  the  variations  in  the  wheel  base;  but,  by  a 
comparison  of  the  figures  given,  it  is  seen  that  the  frame  shown  is  in 


excess  of  210  inches  long  by  about  37  inches  outside  width.  This  is 
about  twice  the  total  length  of  the  average  small  car. 

In  the  bracing  and  arrangement  of  the  different  members,  this 
frame  shows  other  points  of  difference,  the  cross-members,  for 
instance,  being  nine  in  number,  not  including  the  two  diagonal 
cross-members.  The  longitudinal  members,  too,  are  eight  in  number, 
not  counting  the  two  diagonals. 

Rear-Eiid  Changes.  The  locating  of  the  fuel  tank  at  the  rear  of 
the  chassis — a  practice  that  was  brought  into  favor  largely  through 
the  introduction  of  the  vacuum  system  of  fuel  supply — has  resulted 
in  a  number  of  changes  to  the  rear  ends  of  frames.  The  placing  of 
the  fuel  tank  at  the  rear  is  not  new,  and  probaVAy  \\,  'wqkM.  'ct!5\.\v%M«. 


Fie.  387.    Sketch  of  Rm 


esaendal  to  strengthen  the  reai 
carrying  the  spares  inflated  on  ( 
erable  weight  to  the  rear  of  the 


GASOLINE  AUTOMOBILES  525 

extension  for  attaching  the  fuel  tank.  A  cross-member  is  also  utilized ; 
it  serves  as  a  point  of  attachment  for  the  two  rods  supporting  the 
lower  apron  and  for  two  upper  rods  as  well.  This  design  has  merits 
in  that  the  tire  carrier  is  firmly  anchored  and  serves  to  protect  the 
fuel  tank  from  injury  possible  in  operating  in  crowding  tra£5c  where 
rear-end  collisions  are  not  uncommon.  As  may  be  noted,  Fig.  386 
shows  the  method  of  using  an  upper  cross-member  to  prevent  theft 
of  the  tires. 

A  different  type  of  rear  construction  is. shown  in  Fig.  387,  a  Reo. 
Here  the  rear  cross-member  is  gusseted,  and  a  pair  of  substantial  arms 
are  riveted  to  the  cross-member.  These  arms  serve  as  an  anchorage 
for  the  tire  holders  which,  in  turn,  have  a  cross-rod  for  protection. 
Still  another  design  is  shown  in  Fig.  388.  Here  the  side  rail  of  the 
frame  projects  back  of  the  rear  cross-member  of  the  frame  for  a  dis- 
tance of  about  12  inches.  The  fuel  tank  is  suspended  from  these  two 
extended  frame  members  by  means  of  steel  straps  which  pass  around 

the  tank. 

FRAME  TROUBLES  AND  REPAIRS 

The  more  usual  troubles  which  the  repair  man  will  encounter 
are  sagging  in  the  middle;  fracture  in  the  middle  at  some  heavily 
loaded  point  or  at  some  unusually  large  hole  or  series  of  holes; 
twisting  or  other  distortion  due  to  accidents;  bending  or  fracture 
of  a  sub-frame  or  cross-member;  bending  or  fracture  at  a  point 
where  the  frame  is  turned  sharply  inward,  outward,  upward,  or 
downward. 

Sagging.  A  frame  sags  in  the  middle  for  one  of  two  reasons, 
either  the  original  frame  was  not  strong  enough  to  sustain  the  load 
or  the  frame  was  strong  enough  normally,  but  an  abnormal  load  was 
carried,  which  broke  it  down.  Sometimes  a  frame  which  was  large 
enough  originally  and  which  has  not  been  overloaded  will  fail 
through  crystallization  or,  in  more  common  terms,  fatigue  of  the 
steel.  This  occurs  so  seldom,  and  then  only  on  very  old  frames, 
that  it  cannot  be  classed  as  a  "usual"  trouble;  moreover,  it  cannot 
be  fixed. 

When  a  frame  sags  in  the  middle,  the  amount  of  the  sag  deter- 
mines the  method  of  repair.  For  a  moderate  sag,  say  i  to  J  inch, 
a  good  plan  is  to  add  truss  rods,  one  on  either  side.  These  should 
be  stout  bars,  well  anchored  near  the  ends  oi  the  Itama  wA  ^\.^\»Xa» 


526  GASOLINE  AUTOMOBILES 

where  the  frame  has  not  been  weakened  by  excesaive  (irilling.  They 
should  be  given  a  flattene<l  U-shupc,  with  two  (or  more)  uprights 
down  from  the  frame  between  them.  The  material  for  tliem  should 
be  stiff  enough  and  strong  enough  to  withsUind  bending  and  shoulii 
be  finnly  fastened  to  the  under  side  of  tlie  frame.  The  tru^s  rods 
should  be  made  in  two  parts  witli  a  tunibuckli?  to  unite  them,  the 
ends  being  threaiUt!  right  and  left  to  receive  the  tumbuckle. 
Wlien  truss  rtKls  are  put  on  a  saKged  frame,  it  should  Ix;  turned 
over  and  loadetl  on  tlie  under  side;  then  the  tiimbuckles  slioiiUI  be 
pulled  up  so  as  to  force  the  middle  or  sagged  pari  upward  a  fraction 
of  an  int-h,  say  |  to  {  inch,  and  then  the  frame  turned  back,  tlie 
other  parts  added,  and  the  whole  returned  to  use.  A  job  of  this 
kind  which  takes  (jut  the  sag  so  that  it  dfies  not  recur  is  a  job  to  Be 
proud  of. 

Fracture.  Many  frames 
break  because  too  much  metal 
waa  driUed  out  at  one  place. 
Fig.  389  shows  a  case  of  this 
kind.  The  two  holes  were 
drilled,  one  abo%-e  the  other, 


GASOLINE  AUTOMOBILES 


527 


crack,  subsequent  drilling  should  be  at  an  angle,  to  avoid  a  repetition 
of  the  overloading  condition.  In  the  figure,  the  dotted  lines  surest 
the  drilling.  By  staggering  the  holes  in  this  way,  there  is  a  greater 
amount  of  metal  to  resist  breakage  than  would  be  the  case  with  one 
hole  above  the  other — a  method  which  might  preferably  have  been 
used  in  the  first  place. 

So  much  welding  is  done  now,  and  so  many  people  know  of  its 
advantages,  that  every  repair  shop  of  any  size  should  have  a  weld- 
ing outfit.  A  frame  job  is  essentially  an  inside  bencfi  job,  but  a 
large  number  of  cases  of  welding  could  be  done  directly  on  the  car 
outside  the  building,  particularly  in  summer  when  the  outside  air 
and  cooling  breezes  are  desirable.  So,  it  is  well  to  construct  a  small 
truck  on  which  to  keep  the 
oxygen  tank,  acetylene  cylin- 
der, nozzle  for  working,  and  a 
fire  extinguisher.    One  form 

of  a  truck  is  shown   in  Fig.  /i^     'M^  fySENC 

390.  This  truck  is  a  simple 
rectangular  platform  with 
casters,  a  handle,  and  a  rack 
to  hold  the  tanks.  It  saves 
many  steps  and  is  particu- 
larly convenient  in  summer 
months.  This  outfit  is  essen- 
tially a  home-made  affair,  but  , 
the  gas-welding  and  electric- 
welding  manufacturing  companies  have  designed  small  outfits  espe- 
cially for  automobile  repair  work,  which  would  be  preferable  to  the  one 
in  Fig.  390,  especially  where  the  amount  of  repair  work  warrants  a 
reasonable  expenditure  for  a  welding  outfit,  A  description  of  both  gas 
and  electric  outfits  and  instructions  for  their  use  are  given  in  the 
section  on  Welding  for  Automobile  Repair  Work. 

Riveting  Frames.  Tightening  Rivets.  Rivets  securiAg  the  cor- 
ners of  a  frame  or  holding  cross-members,  gussets,  and  plates  often 
work  loose,  particularly  with  the  flexible  type  of  frame  previously 
alluded  to.  The  location  of  the  rivet  and  the  accessibility  of  the  part 
will  determine  how  best  to  proceed  with  the  work.  TV\fe  (ivv^S  X-xwiS^ 
experienced  is  tba  t  of  placing  a  sufficiently  sotid  articXe  a^««\.'CBft'ciN^ 


3iy-Acetyleae  Outfit 


-u«i  lur  cutcing  off  nvets  as  wt 
should  be  of  sufficient  length  1 
When  an  anvil  is  not  avail 
with  success.  Take  a  J-inch  b 
in  the  frame  between  the  rivets 
bolt  with  a  cold  chisel.  Put  on 
and  run  the  nut  down  until  i 
depression  in  the  head  of  the  bol 


Fi|.  391.     Method  oC  Riveting  F 

it,  drill  a  larger  hole  and  use  a  I 
made  of  Norway  iron.  Heat  to  ( 
Riveting  Methods.  There  are 
in  and  the  backing  in.  The  latt 
the  two  plates  to  be  riveted  are  < 
at  A,  with  the  rivets  a  trifle  sni; 
at  B.  With  hot  riveting,  the  hoi 
the  rivet,  but  with  coid  rivets,  1 


GASOLINE  AUTOMOBILES 


529 


by  a  head  formed  at  the  dolly  end  of  the  rivet,  and  additional  blows  of 
the  hammer  tend  to  bring,  the  plates  closer  and  to  hold  them.  The 
backing-in  method  is  practical  in  making  the  various  styles  of  rivet 
heads,  particularly  in  making  the  thin,  almost  flush,  head,  and  an 
advantage  is  that  there 
are  no  reactionary 
stresses  upon  the  thin 
head  as  would  exist  with 
the  driven-in  rivet. 

As  there  is  more 
demanded  of  the  rivet 
replacing  the  old  mem- 
ber, it  is  important  that 
the  work  be  carefully 
performed.  This  applies 
to  the  holes  in  the  plate. 
All  sharp  comers  should 
be  removed,  as  they  af- 
ford an  opportunity  for  the  rivet  to  shear  off  by  external  stress 
or  to  fly  off  under  internal  strain.  A  reamer,  drill,  or  countersink 
can  be  used  in  removing  sharp  corners.  The  face  left  need  not  be 
more  than  A  or  A  inch  wide,  in  order  to  greatly  strengthen  the  rivet 
at  its  weakest  point,  or  where  the  head  joins  the  body.    By  slightly 


Fig.  392.     Adding  a  Tnias  Rod  to  the  Front  of  a  Weak  or 

Damaged  Frame  to  Stren^^then  It  and  Preserve 

the  Radiator 


/y^/Tc/itfe 


^fterT'/in^  JTrofbr" 


X^oop 


3 


top 


Fig.  393.    Bracing  Fractured  Frame  with  Bar  and  Tumbuckle 

chamfering  the  corner  of  the  plate,  the  rivet  is  given  a  corresponding 
fillet,  which  not  only  increases  its  holding  power  but  serves  to  draw 
the  plates  together. 

Frame  Bracing  Methods.    There  are  several  metitioAa  ^>aet^^  ^ 
frame  that  has  been  injured  through  collision  or  Yiaa  ^»^%^  >aeica.>aafc 


530  GASOLINE  AUTOMOBILES 

of  too  light  construction  can  be  repaired.  The  front  of  the  frame  is 
the  chief  ofTender  in  this  respect,  and  many  times  a  leaking  radiator 
is  the  result.  When  repairs  to  the  radiator  fail  to  cure  the  trouble,  it 
may  be  assumed  that  the  frame  is  at  fault.  A  simple  remedy  is 
shown  ill  Fig.  ;i02  nnd  consists  in  bracing  the  frame  by  means  of  a  rod 
iiiid  turribucklc.  The  rod  should  be  about  2  inches  longer  than  the 
wiillli  nf  tlie  frame  and  threaded  for  about  3  inches  on  each  end. 
The  tiiriiliurkle  is  not  essential,  but  it  simplifies  the  work.  In 
itislalhiig  the  brace,  the  inside  nuts  are  screwed  on  first  and  far  enougli 
til  allciw  putting  tlie  rod  in  place.  These  nuts  are  next  screwed  out 
until  they  bear  against  the  frame,  and  the  latter  is  forced  out  until 
any  pressure  that  may  have  existed  on  the  radiator  is  eliminated. 
The  outside  nuts  are  then  screwed  up  snug.  The  advantage  of  the 
turpbuckle  is  that  adjustments  may  be  made  as  required. 

rig.  393  shows  a  method  of  trussing  a  frame  that  was  fractured 
by  the  stresses  of  the  motor  starter.     Even  after  the  fracture  had 
I)een  repaired,  the  driving  gear  of  the  starter  would  not  me.sh  properly    i 
with  the  ring  gear  on  the  flywheel  of  the  engine.     As  the  movement    ' 
was  up  and  down  on  the  frame,  a  truss  was  found  necessary:  while  it 
latter  t CI  attach  one  end  of  the  truss  on  the  left-hand  side 


GASOLINE  AUTOMOBILES 


531 


the  ends.  When  these  are  used,  the  centers  of  the  springs  are  attached 
top  and  bottom,  respectively,  to  the  frame  and  axle.  With  half  of 
the  top  of  the  spring  cut  away,  and  the  cut,  or  thick,  end  attached  to 
the  frame,  this  spring  becomes  a  three-quarter  elliptic.  When  the 
whole  top  of  the  spring  is  cut  away,  so  that  the  spring  is  but  a  series 
of  flat  plates,  bowed  to  a  long  radius,  this  becomes  a  semi-elliptic 
spring.    By  turning  the  semi-elliptic  spring  over,  it  becomes  a  canti- 


Fig.  394.     Typical  Semi-EUiptic  Front  Spring 

lever  when  its  center  and  one  end  are  attached  and  the  load  applied 
to  the  other  end.  The  quarter-elliptic  is  but  a  quarter  of  a  spring, 
while  the  platform  consists  of  three  semi-elliptics — two  as  side  mem- 
bers in  the  regular  position,  while  the  third  is  used  as  a  cross-spring, 
being  inverted  and  attached  at  the  center  to  the  rear  end  of  the  frame 
and  at  its  ends  to  the  side  members.  The  coil  form  requires  no  expla- 
nation and  is  not  now  used  on  cars.  In  addition,  these  forms  are 
modified  by  scroU  ends  and  various  attachments. 


\xr 


Fig.  395.    Typical  Full-Elliptic  Front  or  Rear  Spring 

Semi-Elliptic  Fig.  394  shows  a  front  spring  of  the  semi-elliptic 
type,  the  form  which  is  used  now  for  almost  every  front  spring. 
This  is  a  working  spring  of  the  usual  type,  fixed  at  the  front  end, 
shackled  at  the  rear  end,  attached  to  the  axle  in  two  places,  and  with 
two  rebound  clips  in  addition.  The  latter  are  put  on  the  springs 
to  prevent  them  from  rebounding  too  far,  in  the  case  of  «b  n«^  Ar«^ 
drop*    In  some  cases,  as  high  as  four,  six,  or  eigVvt  ol  \]iies^  ^vv^  ^E&a:^ 


532  GASOLINE  AUTOMOBILES 

be  used.  Many  other  springs  are  made  with  ears,  these  being  clipped 
over  the  next  lower  spring  plate,  the  final  result  being  the  same  as  the 
use  of  many  clips,  but  with  improved  appearance. 

Full-Elliplic.  Full-elliptic  springs  are  the  oldest  form  known- 
Fig.  395  shows  the  construction  of  this  type,  the  upper  and  lower  parts 
being  pivotally  connected  at  tlie  ends.  A  slight  modification  of  this 
form,  known  as  the  scrull-end  full-elliptic  t,\-pe,  is  in  more  extensive 


Fiu    :>'.Hi      Full-Elliplii!  »pting  nith  Scroll  Endu 

use  than  tht?  full-elliptic  plain  tj-pe.  As  Fig.  396  shows,  the  ends  of  the 
upjier  leaves  arc  bent  over.  Euch  carries  an  ej-e,  which  is  connected  to 
the  eye  in  the  end  iif  the  upper  leaves  of  the  lower  half  of  the  spring  by 
means  (if  a  shackle.  This  construction  makes  a  very  soft-riding  spring. 
Three-Quarter  Elliptic.  Very  much  like  Fig.  396  is  the  form 
elliptic  spring,  the  one  having  scroll  ends 


GASOLINE  AUTOMOBILES 


533 


greater  increase.  One  reason  for  this  increase  is  the  great  increase  in 
the  number  of  dropped  frames,  that  is,  frames  unswept  at  the  rear.  To 
this  form  of  frame,  the  three-quarter  elliptic  spring  is  very  well  adapted 
and  makes  a  very  natural, very  good,and  very  easy-riding  combination. 
Platform.  The  platform  type  of  spring  is  used  a  great  deal  on 
large  cars,  as  well  as  on  very  heavy  trucks,  on  account  of  its  ability 
to  carry  heavy  loads  well,  and  also  on  accoimt  of  its  flexibility. 
As  may  be  seen  in  Fig.  398,  it  consists  of  three  semi-elliptic  springs 
shackled  together  at  the  comers.  The  rear  cross-spring  is  usually 
made  shorter  than  the  two  side  springs,  while  the  latter  are  set  off 
center,  making  the  front  of  the  spring,  that  is,  the  part  forward  of 
the  point  of  attachment  to  the  axle  longer  than  the  part  to  the  rear. 
There  are  two  reasons  for  this:  First,  the  front  end  acts  somewhat 
as  a  radius  rod,  the  rear  end  of  the  frame  rising  in  an  arc  of  a  circle 
whose  radius  is  the  front  half  of  the  spring;  second,  this  plan  dis- 


Fig.  398.     Platform  Spring,  Showing  How  Side-  and  Croes-Springs  Are  Shackled  Together 

tributes  the  spring  action  equally  in  front  of  and  back  of  the  axle. 
Since  the  rear  cross-spring  is  fastened  to  the  frame  in  the  center, 
each  half  of  it  is  considered  as  a  part  of  the  side  spring  to  which  it  is 
shackled.  Thus,  the  total. length  of  the  side  spring  in  front  of  the 
axle  is  the  measured  length  of  the  side  spring,  while  the  total  length 
of  the  side  spring  back  of  the  axle  is  considered  as  the  side  length 
plus  half  of  the  cross-spring  length.  The  center  point,  or  point  of 
axle  attachment,  is  not  moved  so  far  forward  as  to  make  these  two 
lengths  equal,  but  in  a  proportion  which  may  be  derived  thus:  Assmne 
a  side  spring  42  inches  long  and  a  cross-spring  35  inches  long;  then  the 
spring  would  be  set  out  of  center  some  4^  inches,  making  the  front 
length  about  25|  inches,  while  the  rear  length  would  be  16|  inches  plus 
half  of  the  .rear  spring,  or  17|  inches,  making  a  total  of  34  inches. 
This  would  give  a  ratio  of  25^  to  34,  or  1  to  1 .333.  If  the  side  mem- 
bers were  50  inches,  the  ratio  would  be  about  1  to  1.25,  and  fot  ^vi^ 
members  shorter  than  42^  the  ratio  would  be  about  \  \jc>  \  Jb. 


534 


GASOLINE  AUTOMOBILES 


Cantilever.  Tlie  cantilever  is,  in  appearance,  a  semi-«Iliptic 
spring  turned  over.  It  gK'ts  its  name,  however,  from  the  method  of 
siis|K'nsi(>n,  ivliicli  is  qnite  different  from  that  of  any  form  of  semi- 
elliptit-  sj>riiij;.     IMort-over.  as  a  part  of  this  suspension,  at  least  one 


end  of  tin-  caiitilivcr  aiifi  sometimes  two  are  finished  up  flat  and 
sqimre  to  sliitc  buck  ami  forth  in  a  groove  provided  for  that  purpose,  a 
bolt  thronjrli  a  «■  ntrai  liole  preventing  the  spring  from  coming  out  of 
its  tjiiLiif.  Oiif  ftiriii,  ^ill<)wn  in  Fig.  399,  has  a  fixed  attachment 
to  tilt'  rear  a\!e.  a  iiivnti-d  attachment  to  the  frame  at  its  center 


GASOLINE  AUTOMOBILES 


535 


the  King,  is  pivotally  mounted  on  the  frame  just  forward  of  its  center. 
Unlike  the  King,  however,  the  forward  end  of  the  spring  has  a  shackle 
which  permits  it  to  swing  when  the  rear  axle  rises  or  falls.  This 
shackle  is  a  very  interesting  feature  of  this  installation,  having  an 
adjustment  which  is  most  unusual  for  a  shackle,  Fig.  401.  Note  how  the 
outsides  of  the  shackle 
have  a  series  of  grooves, 
into  which  the  head  of 
the  shackle  bolt  on  one 
side  and  the  washer  on 
the  other,  fit.  By  setting 
these  in  the  desired 
grooves  and  tightening 
the  nut,  the  position  is 
fixed.  If  this  does  not 
give  the  proper  throw,  it 
is  a  simple  matter  to  re- 
move the  nut  and  make 
a  new  adjustment. 

In  France,  a  form  of  i;«.tu.vet  spnog 

double  cantilever  has  been  tried  out  with  success;  this  form  consists  of 
a  pair  of  cantilevers,  one  above  the  other,  separated  at  the  center  by  a 
•carefully  sized  spacing  block,  which  is  pivotally  attached  to  the  frame. 
The  rear  ends  are  attached  above  and  below  the  axle,  while  the  front 


ends  are  attached  to  two  fixed  points.  Although  the  ends  are  made 
much  thinner  and  more  fiexible  than  those  just  shown,  it  should  be 
noted  that  both  of  them  are  fixed.  The  nse  and  fall  of  the  wheels 
must  be  taken  up  by  the  springs  themselves,  the  pivot  in  the  center 
simply  distributiii^  the  distortion  over  both  the  ItoiA  aD,4TCM.\«SN«». 


rods,  the  main  lead  may  be  : 


Fit.  403.    Uniqua . 

and  the  torque  act  through  tl 
metal  in  the  line  to  the  thrust, 
thethpiixf  o-J  -  ' 


GASOLINE  AUTOMOBILES 


537 


In  the  Hotchkiss  drive,  the  springs  are  rigidly  attached  to  the  rear 
axle,  while  the  front  end  of  the  spring  is  secured  to  the  frame  with  a 
proportionately  large  bolt  through  which  the  drive  is  transmitted. 
Users  of  the  drive  claim  that  it  is  quieter,  that  the  car  holds  the  road 
better,  that  it  is  more  flexible,  and  that  it  avoids  the  road  shocks 
which  are  transmitted  through  stiff  torque  members  from  the  axle 
to  the  frame.  Makers  who  drive  through  the  springs  and  employ 
other  torque  members  claim  that  they  are  not  sacrificing  flexibility  in 
driving  while  eliminating  a  certain  side  sway  and  other  strains  preva- 


Fig.  404.     Combination  Cantilever  and  Semi-ElUptio  Spring  on  Tractor 

lent  when  the  springs  perform  the  functions  of  the  torque.     In  the 
Hotchkiss  drive,  two  universal  joints  in  the  drive  shaft  are  used. 

Unconventional  Types.  Marmon.  A  departure  from  conven- 
tional practice  is  the  spring  used  on  the  Marmon  car  and  shown  in 
Fig.  403.  It  is  a  double-transverse  construction,  consisting  of  semi- 
elliptic  springs  bolted  together  at  the  center,  with  a  curved  block,  or 
hard-maple  cam,  between  them.  This  cam  varies  their  stiffness, 
the  spring  automatically  becoming  stiffer  as  the  load  increases. 
Under  normal  load,  the  stiffness  is  about  170  pounds  per  inch^  but  ^.^^ 
the  springs  are  compressed  the  stiffness  w\l\  reacYv  400  pouxv^^-  'W^^ 


338 


GA^iOLIXE  AUTOMOBILES 


are  shackled  at  one  siile  an<l  fixed  at  the  other,  obtMning  a  perfectly 
parallel  iiiDtinii  to  tile  frame.  There  is  said  to  be  no  roll  as  is  some- 
times fi)iiiiil  with  trjiTi^verse  springs. 

Kiiiij^  Tni'ior.  An  unusual  method  of  suspension  is  that 
employed  on  tlie  Kiuix  tractor,  a  combination  of  a  cantilever  and 
semi-clliptic  spring  at  the  rear  end  of  the  frame.    The  design  shown  in 


Fig.  404  incluiles  lieavy  semi-elliptic  springs,  which  are  attached  to 
the  rear  axle  hy  linif:  clips  and  carry  the  fifth  wheel  of  the  trailer. 
There  is  no  cnnnectinn  lietween  the  springs  and  the  tractor  tiantB,  80 
eight  of  the  trailer  and  load  only.    The  tractor  frame 

g  having  a  pivot  near  its  center  and  a 


GASOLINE  AUTOMOBILES 


539 


Witdon.  Many  makers  use  their  own  special  form  of  springs. 
Fig.  406  shows  the  spring  formerly  used  on  the  Winton  cars,  a  type 
which  might  be  described  as  a  double-purpose  spring.  It  was  made 
in  two  parts,  the  lower  part  consisting  of  a  regular  semi-elliptic  flat 
spring,  while  the  upper  part  was  a  semi-elliptic  fiat  spring  with  scroll 
ends.  The  central  part  of  the  spring  was  treated  as  one,  being 
attached  to  the  axle  in  the  usual  manner;  the  ends,  however,  had  a 
peculiar  appearance,  because  the  upper  and  lower  halves  of  the  spring 
were  of  different  shape.  The  scroll  end  of  the  upper  part  was  sup- 
posed in  itself  to  absorb  many  of  the  small  road  shocks.  The  spring 
was  loosely  attached  to  the  frame  at  each  end  by  means  of  a  double 


Fie.  407.    Thn!e.<]iurt«i  BaoU  Elliptic  Spriuv  on  Winton  Car 


shackle,  made  necessary  by  the  double  action  of  the  spring;  the  tend- 
ency to  flatten  out  increased  its  length,  thus  calling  for  a  forward 
motion  of  the  front  and  a  backward  motion  of  the  rear  ends,  while  the 
different  lengthening  action,  owing  to  the  difference  in  the  lengths  of  ■ 
the  two  parts  of  the  spring  itself,  resulted  in  a  turning  about  a  different 
point. 

For  comparison  with  this  earlier  Winton  spring,  the  latest  form 
is  shown  in  Fig.  407,  It  will  be  seen  that  the  three-quarter  elliptic 
form  has  been  adopted,  with  a  kick-up  at  the  rear  end  of  the  frame. 
If  the  two  tj-pes  are  compared  somewhat  closely,  it  will  be  seen  that 
the  only  change  in  the  frame  part  is  the  kick-up.  The  ue-w  's?.'"^^ 
show  the  scrol]  ends  to  whjcb  Winton  has  al%'ays\>een  v&ttjveX.. 


540 


CASULIXE  AUTOMOBILES 


Ford.  The  form  of  tlie  Ford  spring  has  always  been  distinctly 
liiffert'iit.  Fig.  -lOS  shows  the  front  and  Fig.  409  the  rear  spring  used 
on  FonI  Oiirs,  the  distinction  in  the  front  spring  being  principally 
in  tlie  use  of  a  single  ordinary  inverted  front  spring  set  across  the 
frunie  on  toj)  of  the  nxle,  where  most  makers  use  a  pair  of  side  springs 
set  piirallel  to  tlie  frame.  This  form  is  simple  and  cheap  to  mftke 
iind  assemble,  tlic  tost  of  tlie  spring  itself,  an<l  the  work  of  putting 


it  on  licing  jn>t  ai>ont  half  that  of  the  spring  attachment  of  the 
(iniiaiiry  two-spring  ty|)e.  On  the  otiier  hand,  excellent  riding  quali- 
ties are  ehiiiMfil  f<ii-  it.  A  second  distinction  is  that  the  spring  is 
an  itiviTsiiin  of  the  nsnal  semi-elliptic  type,  the  set  of  the  spring 
lii'ing  dowi^ward  instead  of  upward.  A  third  claim  to  distinction  is 
ill  tlie  use  of  v.iiiaclinrn  steel,  which,  it  is  claimed,  has  a  higher  tensile 
a[id  eotn) (restive  strengih  than  any  other  steel,  and  it  is  practically 
liibreiikitlili'  in  tirrsinn.     This  steel  is  also  being  used  in  many  other 


GASOLINE  AUTOMOBILES 


541 


the  construction  necesatating  it  These  springs  represent  quite  a 
radical  departure,  the  success  of  which  has  been  proved  in  actual 
practice. 

Locomobile.    Fig.  410  shows  the  three-quarter  scroll  elliptic  rear 
spring  used  on  the  Locomobile,  also  the  method  of  shackling  both  ends 


Hi.  ilO.    Tlin»4iuitet  Bcrull  EUiptio  Sprinc  Uaed  on  Locomabils  Cui 

of  the  spring,  and  the  use  of  a  considerable  extension  beyond  the  spring 
clip  of  the  two  upper  leaves.  Fig.  411  illustrates  the  Locomobile 
front  springs,  the  upper  spring  being  used  on  the  1916  model,  and  the 
lower  one  on  the  1917  model.  As  may  be  noted,  the  later  type  is 
2  inches  longer  and  also  flatter,  and  the  distance  between  the  spring 


F^.  111.    Two  BcU  ol  FroDt-Aile  Sprino  on  Locomobila  Cm 

bolt  and  eye  of  the  shackle  is  less  in  proportion  to  the  1916  design.  It 
was  found  that  the  jerky  action  and  fore-and-aft  pitching  of  the  axle 
were  eliminated  by  this  constnictioD,  greatly  improving  the  riding 
qualities  of  the  vehicle. 

Eleetrie  Car  Spring.    The  spring  suspension  of  electric  i^U«a»s«. 
cars  is  similar  to  that  o{  tbe  gasoline  vehicte,  Bent\-«Va.v^i)vc  vis^-o^n'Ci 


542  GASOLINE  AUTOMOBILES 

ifi  front,  am!  full-elliptic  scroll-end  suspension  at  the  rear.     The 
methdi!   of  sluicklinj;  is  similar. 

Varying  Methods  of  Attaching  Springs.  Springs  are  attached 
in  many  ways.  For  example,  tlie  one  shown  in  Fig.  398  might  be 
shackleii  at  the  front  end,  fixed  to  the  axle,  and  fixed  to  the  center 
of  the  frame  at  the  rear,  the  side  and  cross-springs  heiog  shackled 
together.  Again,  the  front  end  might  be  fixed  to  the  frame,  Fig.  412. 
all  other  ciimiectiuns  being  unchanged.  Or,  with  either  method  of 
fixing  tlie  front  end,  the  spring  might  be  swiveled  on  the  axle,  so  as 
to  be  free  to  give  sidewise  without  changing  the  other  properties  of 
the  spring.  Or,  with  either  method  of  fixing  the  front  end  of  the 
spring,  and  with  or  without  flie  axle  swivel,  the  cross-spring  might 
be  pivoted  at  the  central  point  so  as  to  be  free  to  turn  in  any  direction 


GASOLINE  AUTOMOBILES  543 

its  length,  that  is,  in  the  coib,  without  tr^isferriiig  any  of  them  to 
the  body  proper  or,  in  case  of  heavier  shocks,  sharing  with  the  side 
and  rear  springs.  This,  of  course,  is  the  true  function  of  the 
springs— to  allow  the  road  wheels  to  pass  over  the  inequalities, 
rising  and  falling  as  may  be  necessary,  while  the  body  travels  along 
in  a  straight  line,  level  and  parallel  with  the  general  course  of  the  road. 
UTtderslinging.  Almost  any  of  the  spring  forms  shown  and 
described  may  be  underslung,  that  is,  attached  to  the  axle  from 
below.  This  is  a  quite  common  practice  for  semi-elliptic  springs  when 
used  in  the  rear,  but  it  is  very  uncommon  for  front  springs.  Similarly, 
full  eltiptics,  whether  having  scroll  ends  or  not,  are  frequently  under- 


ni.  113.    ttetr-Spriuc  Amnaameiit  OD  1917 


slung.  The  three-quarter  elliptic  form  when  used  in  the  rear  is 
usually  underslung;  the  platform  spring  is  not  underslung  so  often. 
The  cantilever  and  quarter-elliptic  springs  have  been  mentioned  in 
connection  with  the  underneath  attachment.  It  should  be  pointed 
out  that  the  position  beneath  the  axle  lowers  the  center  of  gravity  by 
an  amount  equal  to  the  thickness  of  the  spring  plus  the  diameter  of 
the  axle  plus  twice  the  thickness  of  the  attaching  means,  and  this,  too, 
without  interfering  with  the  quality  or  quantity  of  the  spring  action. 
In  the  case  of  the  cantilever,  the  effect  of  underslin^g  is  to  reduce  the 
straightness  of  the  spring,  that  is,  the  form  when  attached  above 
the  axle  is  almost  straight,  while  the  form  whea  {aste^vni  \i*i.w«  "^sR- 
axle  is  veiy  mudi  curved— has  coosideiable  "opemn^" . 


544 


GASOLINE  AUTOMOBILES 


Shackles  and  Spring  Homs.  Considerable  improvanent  has 
taken  place  in  tlic  mctl»Ki  of  shackling  springs,  and  providon  is  now 
made  witli  some  types  of  springs  for  the  adjustment  of  the  shackles 
and  hiinpcrs  as  w  ell  us  for  renewing  bushings.  Reference  has  been 
made  to  tlie  teiuleiuy  of  design  in  rear-spring  suspension  and  to  the 
undertiluiig  ty]Ks.  Fij:.  413  shows  the  design  employed  with  the  1917 
Premier,  and,  as  may  be  noted,  the  springs  are  slightly  diagonal,  the 
front  ends  coining  inside  the  frame  line,  while  the  rear  ends  are  attached 
to  g(«>sc  ne<-ks  of  a  rear  extension  of  the  frame  pieces.  Shackles  are 
used  for  coiniectiiit;  the  ends  of  the  springs  to  the  extensions. 

A  dcjuirlnre  from  the  conventional  shackle  is  the  safety  double 
shackle  used  un  the  Itainer  1000-pound  capacity  delivery  car,  shown 
in  Fi^.  414.  In  addition  to  the  main  eye  on  the  main  leaf  of  the  rear 
spring,  the  second  leaf  is  extended 
and  formed  into  an  elongated  eye, 
allowance  being  made  for  deflection 
under  load.  The  eye  of  the  leaf  is 
attached  to  tlie  frame  by  the  usual 
rigid  spring  bolt.  Additional  n 
;  furnished  t 


GASOLINE  AUTOMOBILES 


545 


removing  the  cap  of  the  grease  cup,  the  hanger  bolt  is  turned  out,  or 
to  the  left,  with  a  screwdriver,  decreasing  the  distance  between  the 
links.    The '  grease-cup  body  and  lock  nut  are  then  set  up  tight. 


Ks.  41fi.     Svotion  of  AdjuMible  Fraot-^priiic 

Provision  is  made  with  some  types  of  rear  springs  for  eliminating 
play  when  the  rear  ends  are  mounted  on  seats. 

Spring  Lubrication.  All  springs  now  are  fairly  well  lubricated. 
All  shackles  are  provided  with  grease  cups,  and  other  points  of  attach- 
ment to  the  frame  are  provided  with  oil  holes.  Where  the  springs  are 
pivoted  either  on  frame  or  axle,  a  big  grease  cup  is  usually  furnished. 
In  addition,  it  is  now  realized  that  the  maker  can  prevent  much  of 
the  noise  formerly  coming 
from  dry  and  perhaps  rusted 
steel  spring  plates  working 
over  each  other.  There  are 
several  ways  in  which  oiling 
is  accomplished.  The  springs 
are  made  with  an  internal 
lip,  or  groove,  which  is  filled 
with  lubricant  when  they  are 
assembled;  or  between  each 
pair  of  spring  leaves  is  placed 
an  insert  having  a  aeries  of  oil  pockets  throughout  its  length,  each 
filled  with  lubricant  normally  held  in  by  means  of  &  TQ«n!bT«.T^«  (s:iN«t\ 
the  movement  o/  the  spring  plates  and  the  ^eat  een.etB,\»^  ^«n^'^ 


.  ^uisiiuwtnatpracucai 

the  nOmber  of  these  clips  vai 
use  to  which  it  will  be  sub, 
three  clips  and  a  band.  Son 
two  bands.  But  none  indica 
jections  on  the  ends  of  the  le. 
leaf  next  below  it  to  assist  ii 
.  are  in  quite  general  use.  All 
of  spring-leaf  ends,  but  those 
These  are:  the  oval;  the  roun 
fication  of  the  oval;  the  roui 
form,  widely  used  on  motor 
the  diamond  point. 

In  addition,  sizes  have  1 
extent  that  only  five  widths  aj 
motor  trucks.  Those  for  the  f< 
for  the  latter:  2,  21, 2i,  3, 3i, 

As  the  automobile  busii 
qualities  under  more  severe  c 
used  has  been  greatly  improvec 
French  make  excellent  springs 
facturers  going  abroad  for  thei: 


GASOLINE  AUTOMOBILES 


547 


temper;  they  sag  and  show  signs  of  losing  their  set;  plates  break  in  the 
middle,  at  the  bolt  hole,  and  near  the  ends  of  the  top  plate;  and  inside 
plates  break  in  odd  places.  But  more  frequently  the  springs  make  an 
annoying  noise,  a  perceptible  squeak,  because  the  plates  have  become 
dry  and  need  lubricating.  When  this  happens,  and  the  up  or  down 
movement  of  the  car  rubs  the  plates  over  each  other,  dry  metal  is 
forcibly  drawn  over  othey  dry  metal  with  which  it  is  held  in  close 
contact;  naturally,  a  noise  occurs. 

To  lubricate  the  spring,  it  is  well  to  construct  a  spring-leaf 
spreader.  Of  course,  the  job  is  best  done  by  jacking  up  the  frame, 
dismounting  the  spring  entirely,  taking  it  apart  and  greasing  each 
side  of  each  plate  thoroughly  with  a  good  graphite  grease,  then 


Fig.  417.     Handy  Tools  for  Spreading  Spring  Leaves  to  Insert  Lubricant 

reassembUng  it,  and  putting  it  back  under  the  car.  This  is  the  best 
way,  but  it  costs  the  most,  and  few  people  will  have  it  done.  Some- 
times spring  inserts  are  used;  these  are  thin  sheets  of  metal  of  the 
width  and  length  of  the  spring  plates,  having  holes  filled  with  lubri- 
cant over  which  is  a  porous  membrane. 

For  the  ordinary  spreading  job,  the  plates  must  be  pried  apart 
and  the  grease  inserted  with  a  thin  blade  of  steel,  for  instance,  a 
long-bladed  knife.  To  spread  the  leaves,  jack  up  the  frame  so  as 
to  take  off  the  load,  then  insert  a  thin  point  and  force  it  between  a 
pair  of  leaves.  In  Fig.  417,  two  forms  of  tools  for  making  this  forcible 
separation  are  shown.  The  first  is  a  solid  one-piece  forging  with 
the  edges  hardened.  It  is  used  by  sliding  the  edges  ovet  tSoa  «cAa. 
(rf  the  spring  leaf,  then  giving  it  a  twist  to  fotce  Vt  Vxi\>^\*^««^^^2ai^ 


\ 


springs  are  handled,  a  rack  lik 
making. 

Broken  Springs.  WTien  s 
remedy — a  new  plate  or  plates 
it  is  necessary  to  get  home. 


Flf.  lis.    Sunplo  and  1 


shackled  end,  repair  this  sufiicien 
bar  with  a  hole  in  one  end  big  en 
this  bar  to  the  spring  in  place  of 
General  Hints  on  Spring  Re| 
takes  place  where  it  does  not  pr 
should  be  borne  in  miml  ti-"*  *'- 


GASOLINE  AUTOMOBILES  M9 

ness,  but  an  expert  spring  maker  should  be  called  in  to  see  that  the  set, 
or  fit,  is  correct.  The  fitting  of  a  leaf  requires  the  services  of  an 
expert  spring  man;  while  it  appears  to  be  a  simple  matter,  the  lack  ■ 
of  knowledge  by  some  claiming  to  be  spring  experts  is  responsible  for 
breakage  after  the  spring  has  been  repaired.  The  spring  clips  and  the 
nut  of  the  center  bolt  should  be  kept  tight.  The  importance  of 
preventing  the  accumulation  of  rust  on  the  leaves  and  of  lubrication 
has  been  commented  upon. 

SHOCK  ABSORBERS 

Function.  The  ordinary  flat-leaf  springs  of  any  of  the  types 
previously  described  are  inadequate  for  automobile  suspensions. 
When  the  springs  are  made  sufficiently  stiff  to  carry  the  load  properly 
over  the  small  inequalities  of  ordinary  roads,  they  are  too  stiff  to 
respond  readily  to  the  larger  bumps.  The  result  is  a  shock,  or  jounce, 
to  the  passengers.  When  the  springs  are  made  lighter  and  more 
flexible  in  order  to  minimize  the  larger  shocks,  the  smaller  ones  have 
too  large  an  influence,  thus  keeping  the  body  and  its  passengers  in 
motion  all  the  time.  These  two  contradictory  conditions  have  created 
the  field  for  the  shock  absorber. 

The  shock  absorber  is  generally  a  form  of  auxiliary  spring,  the 
function  of  which  is  to  absorb  the  larger  shocks,  leaving  the  main 
springs  to  carry  the  ordinary  small  recoils  in  the  usual  manner;  in 
short,  to  lengthen  the  period  of  shock.  This  is  done  in  a  variety  of 
ways,  and,  as  might  be  expected,  by  a  great  variety  of  devices. 

General  Classes  of  Absorbers.  The  simplest  forms  of  absorbers 
are  the  ordinary  bumper,  or  buffer,  of  rubber  and  the  simple  endless 
belt,  or  strap,  encircling  the  axle  and  some  part  of  the  frame  and 
acting  as  the  rubber  pad  does^-simply  as  a  buffer.  There  are  the 
following  classes  of  the  more  complicated  shock-preventing  and  shock- 
absorbing  devices:  (1)  frictional-plateorcam,  in  which  the  rotation  of  a 
pair  of  flat  plates  pressed  together  tightly — one  attached  to  the  frame, 
the  other  to  the  axle — opposes  any  quick  movement  of  the  two  or  of 
either  one  relative  to  the  other;  (2)  a  coil  spring  used  alone  and  in 
combination — alone  it  is  used  in  the  plane  of  the  coil,  or  at  right 
angles  to  it,  and  parallel  to  the  center  line  about  which  the  coil  is 
wound,  while  in  combination  it  is  found  joined  with  the  simple  leatK« 
strap  or  with  another  ooil  spring  of  equal  ot  90TEie^)aas»  cK.  V%& 


to  the  frame,  having  at  ita  outei 
^milar  plate  at  the  upper  and  * 


Jersey  CUy.  JVeu  Jeraty 


this  type  is  called  the  governed  fric 
When  cams  trt-  "'■— ' 


GASOLINE  AUTOMOBILES 


551 


sharp  jounce,  the  device  becomes  effective.  It  appears  much  like  the 
•Hartford  just  shown,  but  the  construction  is  decidedly  different. 
The  upper,  or  frame,  arm  is  threaded  to  receive  an  Acme-threaded 
screw,  which  is  carried  by  the  lower,  or  axle,  arm.  The  action  of 
screwing  this  out  tends 


Fig.  420 


Laporte  Paaaive  Range  Friction  Type  d 
Shock  Absorber 

C<ntrU9y  of  CharUt  Laporte,  Detroit^  Miehigon 


to  force  the  plate  on  the 
lower  arm,  which  must 
move  outward  with  the 
screw  against  a  rubber 
washer  held  firmly  by  the 
outside  nut  and  cover 
plate.  Thus,  the  scissors 
action  of  the  two  arms 
on  a  sudden  movement  is 
resisted  by  the  compres- 
sion of  the  rubber  washer. 
This  compression  can  be 
increased  or  decreased  by  tightening  or  loosening  the  slotted  outside 
nut,  so  that  the  screw  is  given  less  or  more  movement.  The  rubber 
washer  is  made  with  a  series  of  holes  in  it  to  allow  of  compression. 
Coil  Springs*  Alone  and  in  Combinations.  Springs  Alone. 
The  coil-spring  absorber  is  probably  the  most  widely  used  form, 

primarily  because   it    is      rcr-.^-- ri-r:::^- 

both    good    and    cheap;    z3  bl^™ J  irv-ZTr^^^^c:::^^ 


furthermore,  it  is  simple 
and  adds  little  weight. 
In  most  instances,  the 
coil  is  so  placed  as  to 
compress  along  the  direc- 
tion of  its  center  line. 
One  device,  however,  the 
Acme,  shown  in  Fig.  421, 
works  at  right  angles  to 
this.    It  consists  of  a  pair 


I) 
I! 


Fig.  421.     Acme  Torison  Spring  Fitted  to  Three-Quarter 

Elliptic  Gears 

Courtesy  of  Acme  Tornon  Spring  Company, 
Botton,  MoMoehutetU 


of  coils,  the  two  ends  of  each  being  so  constructed  as  to  go  on  the 
ends  of  the  shackle  bolts  in  place  of  the  usual  shackle.  Wlien  the 
shackle  is  removed,  one  pair  of  ends  is  fastened  to  the  spring  in. 
place  of  the  shadde,  while  the  other  pair  of  euda  lafc^sA  \jei  >iafc  Vtwxs^fc 


GASOLINE  AUTOMOBILES 


553 


:tached  to  the  lower  end  of  the  spring  and  encircles  the  axle.    Hence, 

lis  will  not  interfere  with  upward  movements  of  the  axle,  but 

ily  with  the  downward  ones,  that  is,  the  axle  is  free  to  rise,  but  as 

■on  as  the  car  body  starts  to  rise,  the 

rap-spring  combination  acts  to  prevent 

.    This  is  particularly  true  if  the  axle 

13  reached  the  limit  of  its  motion  and 

13  started  downward  before  the  body 

arts  upward.     In  that  case,  the  body 

.n  move  upward   only  the  amount  of 

ick  in  the  strap  plus  the  give  of  the 

iring,  but  minus  the  amount  the  axle 

IS  already  moved  downward.   This  inex- 

insive   arrangement   has   found    great  ^^vXC 

VOr  on  small  cars.  Hg.  42f     Hoovi^r  shuck   Absorber, 

Double-Coil  Spring  Types.     In  prin-   courun  ht  h.  w.  iioorrr  Compan». 
pie,  the  use  or  two  spnngs  is  not  tJiffer- 

it  from  the  use  of  one.  For  stiuctural  reasons,  however,  it  is  easier 
attach  the  two-spring  form,  while  dividing  the  load  up  into  two 
irts  allows  of  the  use  of 
laller  diameters  and  smaller 
les  of  wire,  thus  making  the 
;vice  appear  more  compact, 
le  of  the  two-spring  forms, 
e  J.H.S.,  is  shown  in  Fig. 
5.  It  consists  of  a  pair  of 
linders  with  coil  springs 
thin.  The  tops  of  the  two 
linders  are  joined  by  a  pin, 
d  this  Joining  pin  is  attached 
the  lower  leaf  of  the  spring, 
side  the  cylinders,  pistons 
e  set  above  each  spring,  and 
ese  are  connected,  this  con- 
ction  being  used  for  the 
her  half  of  the  spring.  At  the  bottom,  the  external  bands  on 
ch  of  the  two  cylinders  are  coimected,  so  as  to  keep  them  ^anlleV. 
all  times.    Thus  any  movement  upwatd  ol  ^e  Yo'wcc  ^ax^  ^  'd^« 


554 


GASOLINE   AUTOMOBILES 


main-leaf  spring  tcniis  to  Hraw  the  enclosure  for  both  shock-absorbing 
springs  upward.  The  springs  themselves  resist  this  and  absoH) 
a  large  part  of  the  niiiveiiient  both  in  force  and  distance. 

Flat-=Plate  Recoil  Springs.  The  third  class,  or  flat-leaf  spring, 
is  a  senii-clliptic  unit  in  miniature.  It  Ls  placed  upon  the  top  of  the 
ordinary  semi-elliptic  spring,  but  it  is  reversed  and  has  a  spacing 
plate  between  the  two.  The  object  of  this  plate  is  to  prevent  recofl 
and  to  eliminate  the  rebound  of  the  car  body  without  restricting  the 
flexibility  of  the  main  springs.  As  shown  in  Fig.  426,  the  Amea 
equalizing  spring  is  constructed  along  these  lines.  As  will  be  noted, 
this  allows  all  downward  movement  of  the  spring,  having  no  influence 
thereupon;  but  when  the  recoil,  the  upward  equal  and  opposite 
reaction,  comes,  the  smaller  upper  spring  opposes  this  reaction  and 


GASOLINE  AUTOMOBILES 


In  the  drawing,  A  ia 
the  upper  section  of  the 
cushion  chamber,  telescop- 
ing into  the  lower  section 
made  up  of  -tube  B  and 
crosshead  E.  The  outer 
tube  C  is  simply  a  guard. 
A  steel  casting  D  is  bored 
out  to  form  a  guide  for  the 
outer  tube  and  crosshead, 
and  has  a  rectangular  pad 
F  machined  for  bolting  the 
whole  device  to  the  bracket 
attached  to  the  frame  of  the 
car.  A  shackle  G  is  fastened 
to  the  end  of  the  car  spring  / 
and  is  pivoted  to  the  cross- 
head  E.  Packing  ring  H  is 
used  to  make  the  inner  cyl- 
inder a  tight  fit  in  the  outer 
casing.  A  breather  J  is 
placed  on  the  side,  through 
which  air  is  drawn  by  the 
upward  movement  of  tube 
B  through  the  medium  .of 
the  tightness  of  packing  ring 
H,  Just  mentioned,  and  this 
air,  on  the  downward  move- 
ment, is  forced  through  the 
passage  K  to  a  port  partly 
surrounding  the  tube  B. 
There  is  no  packing  ring 
between  this  tube  and  its 
guide  D,  so  the  air  blows 
out  and  keeps  the  contact- 
ing surfaces  clean.  A  fur- 
ther protection  is  afforded 
by  the  felt-wiper  ring  L, 


S66 


GASOLINE  AL'TOMOBILtS 


which  retains  the  grease  in  the  g^oo^'e  just  ahove  it.  0  is  a  rod  «>ii- 
nei.'ting  the  two  front  or  rear  springs.  At  the  top  is  the  screw 
cap  M,  covering  the  air  val\e  N,  which  is  designed  to  be  used  just 
as  the  air  valve  in  a  tire. 

The  lower  part  of  the  device  is  filled  with  oil  up  to  a  level  which 
approximates  the  line  Z,  all  above  this  level  being  air  under  pressure. 
Consequently,  the  device  actually  compresses  the  air  through  the 
medium  of  the  oil,  which  is  incompressible.  This  oil  forms  a  sen!  for 
the  air  chamber  and  prevents  its  leakage,  although  the  oil  itself  is 
allowed  to  leak  through,  this  leakage  being  pumj>cd  bark  auto- 
matically by  the  action  of  the  springs.    This  works  oufas  follows: 


GASOLINE  AUTOMOBILES 


557 


When  a  road  obstruction  is  met  and  the  spring  rises,  crosshead 
E  rises  and  the  upward  movement  of  the  oil  takes  the  disc  X  upward 
until  it  strikes  and  carries  with  it  collar  V,  which  lifts  the  plunger  and 
draws  in  a  charge  of  oil.  When  the  air  compressed  in  the  upper 
chamber  of  the  device  expands,  and  the  car  spring  /  and  crosshead 
E  go  down  again,  the  oil  flows  in  the  opposite  direction,  carries  disc 
X  down  against  collar  W,  and  forces  the  plunger  downward.  Then 
the  oil  passes  the  ball  check  Y,  goes  through  the  hollow  plunger,  and 
is  discharged  back  into  the  upper,  or  air,  chamber.  In  the  first  place, 
the  oil  is  put  in  by  taking  off  cap  M  and  taking  out  the  air  valve  N. 
Then  a  special  single-acting  oil  gun  is  used  to  force  it  in,  a  long  nozzle 
being  necessary  to  reach  down  into  the  interior,  with  a  stop  to  limit 
this  downward  distance.  The  maker  recommends  that  an  excess  be 
put  in  and  then  slowly  drawn  off  to  the  right  level. 


Fit'  42D.     Ty^ol  Hemi-^liptic 


As  will  be  seen  from  the  foregoing,  this  device  is  essentially  an 
air  spring,  and  the  air  cushion  does  the  work;  but  it  is  the  oil  below 
it,  with  its  permissible  leakage  and  with  a  pump  to  return  this  leaking 
oil,  which  makes  this  device  practicable.  To  show  the  exterior, 
the  part  which  most  persons  would  see  and  remember,  Fig.  428 
is  presented.  This  figure  shows  the  rear  end  of  a  Pierce  limousine 
equipped  with  a  pair  of  the  Westinghouse  air  springs.  Note  the 
breather,  tie  rod,  cap  at  the  top,  cast  guide  at  the  bottom,  and  other 
parts  previously  shown  and  described. 

Hydraulic  Suspensloiis.  The  majority  of  the  hydraulic  devices 
developed  as  shock  absorbers  consist  of  turning  vanes  connected  to 
the  axle  or  spring,  enclosed  in  a  liquid-tight  case  filled  with  some  heavy 
oil.  There  is  a  hole  of  small  diameter  in  the  case  which  connects  the 
two  sides  of  the  vane,  its  motion  fordng  the  fluid  through  thiB  bole. 


shown  in  Fig.  429,  or  it  may  1 
block.     Where  coi!  springs  are  i 
Attached  either  to  the  frame  en) 
springs  are  used,  one  on  each  sit 
elliptic.     It  is  attached  to  s  in 
free  so  that  they  may  make  coi 
or  a  pad  on  the  pressure  block  of 
load  has  been  applied.    With 
motmted  on  a  seat  forged  integr 
box  dips;  a  coil  spring  is  attached 
bumper.    Under  excessive  deflec' 
flange  of  the  ft^me  and  arrest 
spring.    The  Jeffery  Quad  empit 
of  flat  metal  and  is  termed  a  voliiti 
fastened  to  the  pressure  block. 

SUMMARY  OF 

STEl 

Q.    Which  wheel  travels  far 

A.  The  outer  wheel  must  ti 
turn,  because  it  is  turning  througl 
longer  radius.      On  ver>'  short  t 


GASOLINE  AUTOMOBILES  559 

* 

Q.    How  does  the  usual  steering  arranKeineiit  care  for  this? 

A.  By  having  the  linkage  which  connects  and  steers  the  front 
wheels  arranged  so  that  a  prolongation  of  the  center  lines  of  the  two 
steering  arms  will  pass  through  the  center  of  the  rear  axle. 

Q.    How  does  this  solve  the  difficulty? 

A.  When  this  arrangement  is  used,  any  swing  or  turn  given  to 
the  steering  system,  say  a  turn  to  the  right,  will  swing  the  left-hand 
knuckle  through  a  larger  angle  than  the  right,  although  the  two  are 
connected  together  by  linkage.  This  means  that  the  inner,  or  left, 
wheel  will  swing  about  a  shorter  radius  than  the  outer,  or  right,  wheel, 
since  if  the  two  were  turned  through  equal  angles,  the  two  radii  would 
l>e  equal. 

Q.    What  other  items  coniplk:ate  this  steering  problem? 

A.  The  fact  that  the  wheels  themselves  must  toe  in  slightly  at 
the  front  in  order  to  steer  easily  and  hold  a  straight  line  when  set 
straight.  Furthermore,  the  wheels  must  be  set  with  their  tops  wider 
apart  than  their  bottoms  so  that  the'  line  through  the  center  of  the 
plane  of  the  wheel  strikes  the  cambered,  or  raised,  road  surface  at  a 
right  angle;  this  makes  the  whole  situation  even  worse. 

Q.  Is  the  ordinary  front  axle  of  such  a  design  that  it  gives  per- 
fect steering? 

A.  No.  But  it  represents  a  working  approximation  which  could 
not  be  improved  upon  without  many  needless  complications.  On  a 
sharp  turn,  probably  one  wheel  is  dragged  around  the  curve  for  a 
small  portion  of  its  length,  but  the  distance  is  so  small  that  it  would 
never  be  noticed  by  the  eye  tior  discovered  in  any  difference  of  life 
in  the  tires. 

Q.  How  is  the  turning  of  the  steering  knuckles  about  their 
pivots  obtained? 

A.  The  swinging  movement  of  the  steering  knuckles  is  obtained 
through  a  fore-and-aft  movement  of  the  steering  rod  connected  up  to 
one  of  the  steering-knuckle  arms  by  a  ball  joint. 

Q.  How  is  this  longitudinal  movement  of  the  steering  rod 
obtained? 

A.  By  a  fore-and-aft  swinging  of  the  steering  arm  attached  to 
the  steering  gear. 

Q.  How  is  this  fore-and-aft  movement  of  the  steering  arm 
produced? 


Q.    Why  are  the  worm  and  th 

A,     The  worm  is  used  to  secu: 

few  fonns  of  mechanism  which  will 

the  entire  group  in  the  reverse  dir 

movement  of  the  wheels  to  be  tran 

against  the  driver's  wishes.    In  adc 

to  care  for,  wears  little,  and  ts  highl< 

Q.    What  other  forms  of  mecf 

A.     Bevel  gear,  screw-and-nL 

full  gear  as  distinguished  from  w 

gear,  simple  bent  lever,  and  other  fi 

Q.    What  are  the  disadvantj^ 

A.     With  the  exception  of  the 

or  partially  reversible,  so  if  the  fn 

shock  is  transmitted  back  to  the  dri 

Q.    How  are  steering  wheels 

A.     In  various  ways.     Some  i 

uoderside  of  which  the  arms  of  the : 

Others  have  the  arms  cast  integral  ^ 

are  of  bronze  with  a  molded  rubber 

Q.    Is  the  wood  form,  with  spi 

A.     It  was,  but  it  is  rapidly 

better.    This  construction  is  now  u 


GASOLINE  AUTOMOBILES  561 

Q.    What  is  the  importance  of  the  cross-rod  at  the  front  axle? 

A.  It  is  the  only  member  tyijig  the  two  steering  knuckles 
together.  If  this  rod  is  bent,  the  wheels  cannot  be  steered  accurately; 
if  it  is  broken,  they  cannot  be  steered  at  all.  In  fact,  the  car  cannot 
be  moved  forward  when  the  rod  is  broken. 

Q.    Why  is  the  rod  usually  placed  behind  the  front  axle? 

A.  As  a  protection  against  damage  from  high  spots  in  the  road. 
If  it  is  back  of  the  axle,  it  is  well  protected;  but  if  the  design  places 
the  rod  in  front  of  the  axle,  it  has  no  protection,  and  trouble  is  likely 
to  ensue  on  rough  roads. 

Q.    Where  is  the  front  end  of  the  steering  rod  carried? 

A.  As  a  similar  means  of  protection,  the  steering  rod  is  fre- 
quently carried  over  or  above  the  front  axle,  so  that  the  axle  will 
protect  it.  Even  when  the  design  of  axle,  steering  knuckle,  and  other 
parts  necessitates  this  rod  being  below,  it  is  placed  as  close  as  possible 
to  the  axle  level,  so  as  to  get  the  maximum  protection. 

Q.    What  is  the  function  of  the  steering  knuckle? 

A.     It  forms  a  pivot,  or  bearing,  upon  which  the  front  wheel 
rotates;  but,  in  addition,  it  forms  the  basis  of  steering,  being  capable 
of  turning  about  a  vertical  (or  nearly  vertical)  axis. 
Questions  for  Home  Study 

1.  Describe  the  complete  steering  mechanism  of  the  Pierce- 
Arrow  car. 

2.  Why  is  it  better  to  steer  with  the  front  wheels  than  with  the 
rear  wheels? 

3.  Tell  in  detail  how  a  worm  and  sector  mechanism  works. 

4.  Describe  the  working  of  a  worm  and  nut  device.  Is  it  better 
than  a  worm  and  gear  and  if  so,  why? 

5.  How  is  the  Genuner  steering  gear  adjusted  (a)  for  wear  of 
the  worms;  (b)  for  looseness  of  the  steering  wheel?  How  is  it 
lubricated? 

6.  Describe  the  Hindley  worm.  What  are  its  advantages; 
disadvantages? 

7.  Select  and  describe  one  form  of  steering-wheel  construction. 

8.  How  would  you  adjust  a  steering  rod  for  (a)  length;  (b) 
wear? 

9.  Tell  the  advantages  and  disadvantages  of  the  various  possible 
positions  for  the  cross-rod ;  for  the  steering  rod. 


latter  fits  in  between  the  two  par 

has  a  single  central  bearing. 

Q.    How  does  the  inverted 

A.    In  the  inverted,  or  revert 

with  a  single  central  bearing,  whilt 

-or  Y,  and  has  the  two  bearings,  on 

Q.    Which  of  these  two  forn 

A.    There  is  little  choice,  bi 

Elliott  form  because  it  gives  a  stiff 

which  is  generally  a  good  size  rig 

can  be  made  large  enough  in  thii 

anti-friction  bearings.    This  b  noi 

Q.    How  Is  the  Lemoine  axle 

A.     The  steering  knuclcle  an 

letter  L.    The  axle  end  is  plain  anc 

end  of  the  steering  pivot.    In  tin 

its  vertical  leg  eirtending  upwards,! 

80  to  speak.    As  constructed  in  Ut 

is  turned  downward,  so  that  the  a: 

Q.    What  are  the  advantages 

A.     Both  axle  end  and  knuc 

structed  more  cheaply.  Moreover, 

or  disassembled  more  readily  and  qi 


GASOLINE  AUTOMOBILES  563 

Q.    What  are  the  usual  axle  materials? 

A.  Modem  practice  restricts  front  axles  to  hand-  and  drop- 
forged  steel,  to  tubular  centers  with  forged  ends,  and  to  pressed  steel. 
The  latter  is  little  used,  however.  Cast  steel  and  manganese  bronze 
as  well  as  wood,  have  been  used. 

Q.    What  are  the  usual  axle  bearings? 

A.  Ball,  roller,  and  plain  bearings  are  widely  used.  For  the 
sake  of  simplicity  and  compactness,  the  steering-pivot  bearings  are 
often  plain,  while  the  wheel  bearings  on  the  knuckle  end  are  about 
evenly  divided  between  ball  and  roller.  Thrust  bearings  are  about 
evenly  divided  between  plain  steel  bearings  with  bronze  washers,  on 
the  one  hand,  and  with  ball  bearings,  on  the  other. 
Questions  for  Home  Study 

1 .  Describe  a  good  method  of  truing  front  wheels. 

2.  How  would  you  determine  that  front  wheels  were  out  of 
alignment? 

3.  Describe  in  detail  the  (a)  Overland  front-axle;  (b)  the 
Christie;  (c)  the  Marmon. 

4.  How  are  axles  lubricated,  with  reference  to  (a)  wheel  bear- 
ings; (b)  steering  pivots;  (c)  thrust  washers  or  thrust  bearings? 

5.  What  are  the  disadvantages  of  cast  front  axles? 

6.  Are  ball  bearings  better  than  roller  bearings  for  front-axle 
pivots  and  if  so,  why? 

7.  Describe  in  detail  the  process  of  straightening  a  bent  front 
axle.    Would  you  use  a  template  and  if  so,  why?  * 

FRAMES 

Q.    What  is  the  need  for  a  frame  in  an  automobile? 

A.  Every  automobile  needs  a  frame,  stiff  and  strong  enough  to 
support  all  the  units  for  power  development  and  use,  down  to  the 
springs. 

Q.  Is  there  any  radical  difference  between  pleasure-car  and 
motor-truck  frames? 

A.  None,  except  that  the  truck  frame  must  carry  a  much  heav- 
ier load  and,  therefore,  needs  to  be  stiffer  and  stronger  and  that  it 
must  cost  less  relatively,  thus  necessitating  a  form  or  shape  which  is 
cheaper  ta  construct. 

Q.    What  materials  are  used  for  frames? 


Q.    Is  steel  tubing  used  for 

A.     Frames  are  no  longer  coi 

this  has  been  tried,  but  some  d 

for  the  support  of  the  engine, 

Q.    Is  structural  steel  widel} 

A.     For  pleasure  cars  very  U 

but  in  gradually  decreasing  quan 

better  and  cheaper  frames  of  pres: 

Dating  any  and  all  arguments  in 

Q.    What  Is  a  frame  "kick-u 

A.     When  the  rear  end  of  a 

level  is  bent  sharply  upwanis  fro 

inches,  beginning  just  forward  of  1 

rear  end  of  the  frame  on  this  highe 

called  a  kick-up. 

Q.    What  Is  the  purpose  of  a  I 

A.     It  lowers  the  central  part  i 

a  lower  step,  incidentally  lowering 

the  car  safer.     It  raises  the  rear  ei 

Q.    What  is  the  sh^e  of  the 

A.     It  is  gradually  assuming 

the  frame  formed  a  rectangle,  wit] 

was  found  advantageous  to  narrov 

for  tlio  »iv."t  "■! — '"  '-  •  -  '  ■' 


GASOLINE  AUTOMOBILES  566 

then  became  a  logical  step  to  make  the  frame  taper  from  front  to  rear 
continuously,  with  straight  sides.  This  is  the  form  which  all  frames 
are  assuming  now. 

Q.    In  what  other  ways  do  modem  frames  differ? 

A.  The  rear  cross-member  is  being  eliminated  very  widely,  as 
is  also  the  front  cross-member,  so  the  triangular-shaped  frame  is  not 
closed  at  either  end.  Formerly,  the  depth  of  the  frame  was  pretty 
much  the  same  from  front  to  rear,  but  now  this  tapers  very  materially 
from  the  front  up  to  the  middle  and  then  down  again  at  the  rear.  A 
good  stiff  typical  frame  would  be  perhaps  2^  inches  to  3  inches  deep 
at  the  front,  6  inches  deep  in  the  middle,  and  perhaps  2 J  inches  to  21 
inches  deep  at  the  rear.  In  short,  except  for  perhaps  20  to  24  inche^  of 
length  right  in  the  middle,  the  frame  depth  would  differ  continuously. 

Q.    What  is  the  advantage  of  varying  the  depth  so  much? 

A.  It  eliminates  every  pound  of  excess  weight,  putting  much 
metal  where  there  is  heavy  load  and  severe  stresses  and  little  metal 
where  the  load  and  the  stresses  are  Ught. 

Q.    Is  this  form  of  construction  more  expensive? 

A.  No.  The  art  of  pressing  the  frame  out  of  sheet  steel  has  been 
developed  through  large  quantity  production  to  such  an  extent  that  a 
frame  of  this  type,  with  a  constantly  varying  depth,  costs  no  more  than 
a  straight  frame  cost  four  years  ago. 

Q.    Does  this  form  give  the  repair  man  more  to  do? 

A.  No.  On  the  contrary,  frames  give  less  trouble  in  the  way  of 
sagging,  breaking,  or  cracking  than  ever  before.  The  frame  troubles 
of  today  are  mainly  due  to  poor  or  Ijght  design,  in  an  effort  to  lower 
weight  too  f^r,  or  to  accidents. 

Q.    What  has  been  the  effect  of  cantilever  springs  on  frames? 

A.  One  effect  of  cantilever  springs  for  rear  use  has  been  to 
eliminate  the  rear  cross-member,  as  spoken  of  previously.  Another 
effect  has  been  to  continue  the  deepest  section  back  quite  a  few  inches 
to  the  point  of  support  of  the  front  end  of  the  cantilever. 

Q.    Is  the  trussed,  or  latticed,  frame  widely  used? 

A.  No.  Only  by  one  or  two  makers,  although  a  few  heavy  cars 
have  a  truss  rod  below  the  main  frame  to  add  stiffness  and  strength. 
The  trussed,  or  latticed,  frame  is  a  new  departure  m  frame  design. 

Q.  What  are  the  noticeable  tendencies  in  frame  constniction, 
other  than  those  already  mentioned? 


change  this. 

Questions  for  Home  Study 

1.  How  would  you  repair  a 
end;  (b)  center;  (c)  rear  end;   ( 

2.  Describe  the  method  o\ 
coy-acetylene  process. 

3.  Describe  the  following  fr 
(b)  Marmon;  (c)  Fergus. 

4.  How  is  the  Franklin  woe 

5.  How  is  what  is  called  ai 

6.  Tell  how  to  remove  and 

7.  What  material  is  usually 
li^t  pleasure  car;  (c)  for  a  heav 

8.  Give  the  advantages  and 
frames. 

SPRINGS  AND  St 

Q.    What  is  the  need  for  veh 

A.  To  support  the  load  in  a  1 
jars  of  the  road  will  not  be  transmi 
addition,  a  flexible  connection  bet 
wheels  is  needed. 

Q.    How  many  recognized  di 
A.    Seven;  all  of  which  are  n 

itieS  for  all  kinria  ..f  i^-J 


GASOLINE  AUTOMOBILES  567 

Q.    What  is  the  shape  of  the  semi-elliptic? 

A.  This  form  has  a  slight  bow  upwards,  the  two  ends  being 
slightly  higher  than  the  middle.  The  middle  is  attached  to  the  axle 
and  the  ends  to  the  frame,  and  when  load  is  applied,  these  ends  come 
down,  flattening  the  spring  so  that  it  approaches  a  straight  line. 

Q.    Describe  the  full-elliptic  spring. 

A.  This  form  has  the  shape  of  two  semi-elliptics,  one  inverted 
and  set  on  top  of  the  other.  This  gives  it  the  appearance  of  an  elon- 
gated letter  O  with  points  at  the  ends.  The  lower  half  is  attached  to 
the  axle  and  the  upper  half  to  the  frame,  and  loading  tends  to  bring  . 
the  two  halves  closer  together,  flattening  the  O  still  farther. 

Q.    What  is  the  form  of  the  three-quarter  elliptic  spring? 

A.  This  consists  of  a  flat  lower  semi-elliptic  member  and  a 
highly  curved  quarter-elliptic  upper  member,  the  two  being  joined 
by  means  of  a  shackle.  With  the  exception  of  the  difference  in 
curvature  of  the  two  parts  and  the  use  of  the  shackle  to  join  them, 
this  has  the  appearance  of  a  full  elliptic  with  the  upper  forward 
quarter  cut  away.  When  loaded,  both  members  give  slightly,  the 
upper  quarter  more  than  the  lower  half.  The  shackle  gives  a' consid- 
erable difference  in  this  action  from  that  of  the  full-elliptic. 

Q.    What  is  the  platform  spring  like? 

A.  This  spring  consists  of  three  semi-elHptics  joined  together  at 
the  ends  so  as  to  form  three  sides  of  a  rectangle.  The  two  sides  are 
fastened,  respectively,  to  the  axle  at  the  middle  of  each,  to  the  frame 
at  their  front  ends,  and  to  the  third  spring  at  the  rear  ends.  The  rear 
spring  is  inverted  and  its  center  is  fastened  to  the  center  of  the  rear 
end  of  the  frame,  while  its  ends  are  shackled  to  the  rear  ends  of  the  two 
side  springs.  This  makes  a  combination  in  which  the  normal  semi- 
elliptic  spring  action  is  modified  somewhat  by  the  inversion  of  the  rear 
cross-member  and  by  the  use  of  shackles  at  the  ends  of  all  three. 
While  popular  three  or  four  years  ago,  it  is  now  going  out  in  favor  of 
the  three-quarter  elliptic. 

Q.    What  is  the  cantilever  spring  like? 

A.  It  consists  of  an  inverted  semi-elliptic  fixed  or  shackled  to  the 
outside  of  the  frame  at  the  front  end,  hinged  or  pivoted  slightly 
forward  of  its  center  to  the  outside  of  the  frame,  and  having  its  rear 
end  attached  to  the  upper  or  lower  surface  of  the  rear  axle.  It  is  used 
in  greater  lengths  than  any  other  form  of  spring  and  b  very  popular. 


SeS  GASOLINE   AUTOMOBILES 

It  is  the  most  simple  spring  now  in  use  and  is  said  to  give  tlie  easier 
riding  of  all. 

Q.     What  is  the  quarter-elliptic  spring  like? 

A.  Tliis  Is  simply  wliat  its  nume  indicates,  one-half  of  a  semi- 
elliptif  or  oiic'-<|ii;irk'r  tif  a  full-elliptic.  Its  front  end  is  fixefl  to  the 
frame  out-side,  and  the  rear  end  is  shackled  or  allowed  to  slide  on  the 
rear  axle.  It  is  generally  inverted.  In  realitj;,  it  is  a  cheap  substi- 
tute for  the  cantilever  or  inverte<I  semi-elliptic,  this  use  being  allow- 
able  because  of  the  light  weight  of  both  car  and  load. 

Q.     Is  this  used  in  any  different  way? 

A.  Sometimes  ii  piiir  of  these  is  used,  one  alxive  the  other,  with 
the  idea  of  dimbling  the  resistance  or  rather  of  giving  equal  resilience 
with  but  half  the  movement. 

Q.     What  is  meant  by  underslinging? 

A.  When  this  refers  to  frame,  the  entire  frame  is  place<!  below 
the  springs.  This  has  gone  out  of  use.  When  referring  to  springs, 
tills  means  placing  the  spring  below  its  support,  as  below  the  rear  axle. 
This  construction  lowers  the  frame  and  center  of  gravity  by  the 
thickness  of  the  spring  plus  its  seat  plus  the  diameter  of  the  rear  axle, 
sometimes  amounting  to  a.  total  of  five  indies.     It  is  growing  rapidly 


l!!Jf1'l!H.' 


i 

I 


GASOLINE  AUTOMOBILES 

PART  VI 


FINAL-DRIVE  GROUP 

REAR  AXLES 

TRANSMISSION 

Units  in  the  Final  Drive.  Generally  speaking,  the  transmission 
is  located  in  the  middle  or  forward  end  of  the  chassis.  When  this  is 
the  case,  the  final  drive  begins  right  at  the  rear  end  of  the  transmission. 
The  units  back  of  the  transmission,  then,  would  be  a  universal  joint; 
a  driving  shaft;  possibly  another  universal  joint;  the  final  gear 
reduction;  rear-axle  shafts  and  enclosure;  the  differential;  the  torque 
rod,  or  tube,  or  substitute  for  it;  the  wheels;  the  brakes;  the  tires; 
and  other  smaller  units. 

Even  when  the  transmission  is  placed  on  the  rear  axle,  this 
general  layout  is  changed  little,  and  the  transmission,  which  has  been 
coveFed  in  detail  previously,  is  not  considered  again.  In  the  case  of  a 
chain  drive,  which  is  still  used  on  one  pleasure  car  or  perhaps  two,  on 
a  number  of  small  trucks,  and  on  a  large  number  of  large  trucks,  this 
layout  is  changed  considerably.  In  the  large  trucks,  the  transmission 
in  perhaps  90  per  cent  of  all  cases  would  be  in  a  unit  with  the  jack- 
shaft,  which  means  that  for  consideration  in  the  final-drive  group 
there  would  be  only  the  driving  shaft  to  the  transmission;  the  joint 
or  joints  in  it,  if  any;  the  chains  and  the  method  of  adjusting  them; 
the  rear  axle  and  wheels;  the  brakes;  the  differential,  of  necessity 
becoming  a  part  of  the  transmission;  and  the  jackshafts. 

To  make  this  clear  and  point  out  the  various  units,  it  will  be 
noted  in  Fig.  430  that  it  is  a  unit  power  plant.  Directly  back  of  the 
transmission  is  the  first  universal  joint,  driving  through  the  hollow 
propeller  shaft  to  the  rear  axle,  in  front  of  which  is  the  second  universal 
joint.  The  rear-axle  group  includes  the  axle  shafts,  differential  gears, 
final  gear  reduction,  gear  housing,  and  the  wheels.  The  torque 
reaction  of  the  drive,  to  be  explained  later,  is  taken  by  the  torque  rod, 
marked  in  the  drawing,  which  connects  the  rear  axle  to  the  under 


GASOLINE  AUTOMOBILES  571 

right  angles  to  each  other,  that  is,  the  forks  are  laid  in  planes  which 
are  at  right  angles.  The  fork  on  one  shaft  is  fastened  to  a  pair  of 
diametrically  opposite  pins,  while  the  fork  on  the  other  shaft  is  fas- 
tened to  the  other  pair  of  diametrically  opposite  pins.  Each  shaft  is 
able  to  turn  on  its  pins  about  a  line  through  the  center  of  both.  As 
these  two  lines  are  in  planes  which  are  at  right  angles  to  one  another, 
but  intersect  at  a  common  center,  movement  is  possible  in  either 
plane,  or  by  combination  movements  of  both,  in  any  direction. 

Slip  Joints.  In  many  situations,  a  real  universal  joint  is  not 
needed,  since  the  parts  are  not  actually  free  to  move  in  all  directions; 
but  what  is  needed  is  slight  freedom  up  and  down  or  sidewise 
combined  with  possible  fore-and-aft  movement.  In  such  cases  a  slip 
is  used,  the  name  giving  the  idea  of  a  joint  which  allows  one  shaft  to 
slip,  or  slide,  inside  the  other.  The  general  constructibn  of  slip  joints 
varies.  Sometimes  a  round  gear  is  fastened  to  the  end  of  one  shaft; 
this  gear  has  a  fairly  large  diameter  and  many  teeth,  with  the  teeth 
chamfered  to  an  unusual  extent — almost  rounded,  in  fact.  An  internal 
gear  of  the  same  size  and  number  of  teeth  with  similarly  rounded 
profiles  is  meshed  with  the  hollow  gear  of  the  other  shaft.  Both 
gears  have  unusually  wide  faces. '  This  combination  gives  an  action  that 
is  almost  universal,  and  also  allows  lateral  sliding  of  perhaps  ^  inch. 

The  second  form  of  slip  joint  consists  of  a  squared  shaft  and 
square  enclosure.  The  end  of  the  shaft  has  a  member  split  along  a 
central  Une  attached  to  it;  the  exterior  approximates  a  round  of  large 
diameter,  but  the  interior  is  machined  to  a  perfect  square,  one-half 
in  each  part  of  the  spUt  member.  Attached  to  the  end  of  the  other 
shaft  is  a  member  machined  to  an  exact  square,  but  slightly  rounded 
in  a  fore-and-aft  direction.  The  square  will  drive,  no  matter  in  what 
part  of  the  housing  it  is  located,  so  that  considerable  fore-and-aft 
sliding  is  possible.  In  addition,  the  rounded  surface  of  the  square 
gives  an  approximate  universal  effect.  The  split  housing  is  used  to 
make  assembling  and  disassembling  easier  and  much  quicker.  Some- 
times such  a  housing  is  put  on  the  end  of  each  shaft,  the  connecting 
member  being  made  in  the  form  of  a  dumb  bell,  but  with  two  square 
ends — one  to  work  in  each  squared-out  housing.  In  this  way  the 
effect  of  a  full  universal  joint  with  the  fore-and-aft  sliding  is  obtained 
at  less  cost,  and  with  easier  assembling  and  disassembling  as  extra 


forma  have  been  produced, 
the  two  shafts  bolted  to  tl 
The  metal  will  bend  and  g 


Fig.  431.     Laminalrcl  Dinro  Foroiiiu 
Shufl  C-oupHng 
CourUn/  tf  Thrrm-id  AvUxr  Comp 
Trenbm.  ,%>ir  Jir,rii 

end  of  each  shaft,  a.s  the  figun 
convenient  for  the  ronnlr  Tr,~ 


GASOLINE  AUTOMOBILES 


573 


Shaft  Drive.  In  its  usual  form,  shaft  driving  in  an  automobile 
involves  simply  a  propeller  shaft  interposed  between  the  rear  axle 
and  a  revolving  shaft  in  tlie  car  above  the  spring  action.  There  is 
some  provision  for  taking  the  torque  of  the  shaft  and  of  the  axle  so 
that  they  shall  maintain  their  proper  relative  positions. 

In  Fig,  432,  a  typical  short  driving  shaft  with  its  two  universal 
joints  is  shown.  This  is  such  a  shaft  as  would  be  used  in  the  car 
shown  in  Fig.  430,  except  that  the  latter  is  a  long  wheel-base  car  with 
its  transmission  in  a  unit  with  the  motor  and  clutch  and  thus,  far 
forward.  This  combination  necessitates  a  very  long  propeller  shaft. 
The  one  shown  is  actually  from  a  car  having  a  short  wheel  base,  with 
the  transmission  located  amidships.  This  is  a  combination  which 
calls  for  a  fairly  short  propeller  shaft. 

The  short  shaft,  shown  in  the  figure,  is  a  solid  shaft.  The  modem 
tendency  toward  lighter  weights  is  being  worked  out  in  the  case  of 


Fi|.  432.     Ordiury  Driving  Shift  af  Solid  Form  with  Two  Uaivemil  JoinU 

propeller  shafts,  and  many  are  now  made  hollow.  By  making  the 
diameter  slightly  larger  and  having  a  large  central  hole,  unusually 
light  weight  is  obtained  with  all  the  strength  of  the  solid  form.  In 
addition,  the  larger  diameter  hollow  shaft  has  more  rigidity  than  the 
small  diameter  solid  form,  and  in  many  of  the  modern  cars  without 
torque  or  radius  rods,  unusual  rigidity  of  the  driving  shaft  is  necessary. 
Other  forms  have  been  used  for  the  driving  shaft,  but  they  come  more 
or  less  in  the  freak  class.  About  two  years  ago,  a  car  was  brought  out 
with  a  spring,  or  flexible,  shaft,  which  consisted  of  a  rectangular 
member  of  considerable  height,  but  fairly  thin.  The  idea  was  not  only 
to  transmit  the  power  of  the  engine,  but  to  do  it  in  a  flexible  manner, 
that  is,  the  shaft  was  supposed  to  alisorb  all  the  sudden  changes, 
such  as  quick  acceleration  or  quick  braking.  At  the  same  time,  one  of 
the  eiectric-car  makers  brought  out  a  chassis  with  a  square  driving 
ahaft  of  very  small  size.    This  ser\'ed  the  same  purpose  as  the  flexible 


GASOLINE  AUTOMOBILES 


575 


tion  opposite  to  that  in  which  the  shaft  is  turning.  In  some  cars, 
this  is  counteracted  by  the  use  of  slightly  heavier  springs  on  one 
side.  The  advantages  of  the  shaft  drive  are  the  complete  enclosure 
of  all  working  elements,  with  their  consequent  protection  from  dirt 
and  the  assurance  of  their  proper  lubrication. 

The  final  drive  of  the  Ford  automobile,  in  which  the  end  of  the 
propeller  shaft  is  shown  at  .(,  together  with  the  bearings  in  which  it  ■ 
revolves,  the  pinion  by  which  it  drives  the  car,  the  axle,  the  differen- 
tial, and  the  bearings  of 
the    floating    inner    ele- 
ments of  the  axle  is  illus- 
trated in  Fig.  4:J3. 

The  shaft  drive  does 
not  necessarily  include 
the  use  of  bevel  gears  for 
the  final  reduction  at  the 
rear  axle;  in  fact,  almost 
aiij-  form  of  gears  maj' 
be  used.  In  one  well- 
known  shaft-driven  com- 
mercial car,  the  final 
gears  consist  of  a  pair 
of  plain  spur  gears,  while 
on  the  shaft  of  the  second 
»f  these  gears  is  a  pair  of 
bevels. 

As  soon  as  the  bevel 
gear  final  reduction  dis- 
closed its  limitations  and 
disadvantages,  designers  started  to  displace  it.  One  of  the  earliest 
formsofgearusedfor  this  purpose  was  the  worm,  an  example  of  which 
can  be  seen  in  Fig.  4.^.  This  figure  shows  the  worm  placed  above  the 
wheel,  but  the  lower  position,  which  is  aL-to  used,  haK  the  advantage  of 
copious  lubrication.  In  the  form  shown,  the  wheel  must  come  directly 
t>eneath  the  worm  so  that  the  differential  may  l>e  set  inside  of  it. 

The  worm  is  usually  more  suitable  for  slower  moving  vehicles 
which  have  a  large  reduction  of  spool  between  engine  and  rear  wheels, 
that  i^  to  say,  it  is  peculiarly  fitted  to  electrics  and  motor  trucks  of  all 


576 


GASOLINE  AUTOMOBILES 


sizes,  on  whicli  it  is  finding  wider  and  wider  use.  On  pleasure  vars 
of  the  average  size  and  type  where  a  speed  as  high  as  rtO  m.p-h.  nr 
higher  is  espect«l  hy  nil  mneemwl,  it  has  not  been  found  suitable  and 
consequently  is  not  iieinji^  used, 

A  later  fomi,  wiiicli  is  designed  tti  replace  the  straight  bevel,  i^ 
the-  spiral  bevel.  ^Tliisis  primarily  a  bevel  gear  with  spinil  teeth,  the 


*^— i•i^^^^ 


idea  being  to  inciir]K>riile  in  thc'  bevel  gear  the  aj^lvantages  of  the 
spirally  shaped  womi  tooth,  without  its  disodvautiiges.  As  Fig.  4:J5 
shows,  this  makes  a  \(t_\-  compart  and  neat  arrangement,  the  differ- 
ential fitting  within  the  larger  gear  in  the  some  mamier  as  with  the 


D<, 


ihh-Cluiin  Drive.    The  U8e  of  double  chains,  by  whieh  the 
wheels  lit"  an   iiiitomobile  are  drivi-ii   fnim   a  cfinntershiift 


GASOLINE  AUTOMOBILES 


577 


merits  and  the  means  of  securing  these  merits  in  positive  and  per- 
manent form  will  result  in  their  more  general  use. 

A  tj-pical  roller  chain  of  the  type  most  used  for  automobile 
drives  is  illustrated  in  Fig.  436. 

Silent  chains,  of  the  types  illustrated  in  Figs.  437  and  438,  possess 
certain  points  of  superiority  over  roller  chains  and  are  therefore  com- 
ing increasingly  into  use  for  camshaft  drives,  in  gear  boxes,  etc.,  and 
there  is  some  possibility  that  they  will  find  more  extensive  application 
to  final  drives  than  at  present. 

The  action  of  a  silent  chain  is  illustrated  in  Fig.  438,  in  which  it 
is  seen  that  as  the  chain  links  enter  the  sprocket  teeth  the  chain 
teeth  at  the  same  time  close  together  and  settle  m  the  sprocket  with 


■isr   fvs/r/or/ 


Fi|.  438.     Action  of  Sileot  Chain  and  ^cwkMi 

a  wedging  action  that  causes  them  to  be  absolutely  tight,  but  without 
any  more  binding  than  there  is  backlash. 

To  keep  silent  chains  from  coming  off  sidewise  from  the  sprockets 
over  which  they  run,  it  is  customary  to  make  the  side  links  of  deeper 
section  than  the  center  hnks,  as  is  illustrated  in  Fig.  437.  Another 
successful  scheme  is  grooving  the  sprocket  to  receive  a  row  of  special 
center  links  in  the  chain,  which  are  made  deeper  than  the  standard 
links. 

At  present,  only  one  American  pleasure  car,  the  Metz,  has 
final  drive  by  means  of  silent  chains.  This  is  a  small  car  with  a 
friction  transmission,  the  drive  from  the  ends  of  the  cross-shaft  being 
by  enclosed  silent  chain  to  each  rear  wheel. 

Torque  Bar  and  Its  Function.  It  is  a  well-known  fact  that  action 
and  reaction  are  equal  and  opposite  in  direction,  so  that  if  a  gear  is 
turned  fordbly  in  one  direction,  say  clockwise,  there  is  a  reaction  in 
the  opposite  direction,  or  counter-clockwise.  This  is  the  iumple  basic 
reason  for  atorquebar.ortorque  rod,  on  an  automobile.  It  is  needed 
with  any  form  of  final  drive,  but  it  takes  different  forms,  aiceotdv»^V> 


578 


GASOLINE  AUTOMOBILES 


Uie  tj'pe  of  gear  iisccl.  The  bevel  and  spiral  bevel  used  on  S8  per  cent 
of  the  1917  cars  are  explained  in  detail  as  follows:  Fig.  439  shows  the 
rear  end  of  a  typical  pleasure-car  chassis.  The  engine  is  rotating 
clockwise,  and  so  is  the  driving  shaft  A,  as  shown  by  the  arrow.  The 
shaft  turns  the  pinion  B  in  a  clockwise  direction,  which  rotates 
.  the  large  bevel  C  so  that  its  top  turns  toward  the  front  of  the  car. 
The  bevel  C  turns  the  rear  axle  I)  and  the  rear  wheek  (not  shown) 
in  the  same  direction;  so  the  car  moves  forward. 

In  addition  to  tlie  gear  C  and  shaft  D  turning  easily  in  the  axle 
housing  K,  there  is  an  eijiial  and  opposite  reaction  which  tends  to  keep 
them  stationary,  while  the  bevel  pinion  B  and  driving  shaft  -I  tenii 
to  rotate  around  the  rear  axle  a?  u  center  in  a  counter-clockwise  direc- 


GASOLINE  AUTOMOBILES 


579 


Driving  Reaction.  As  has  been  stated,  the  power,  or  torque,  of 
the  motor  is  used  to  rotate  the  rear  wheeb.  These  stick  to  the  pave- 
ment or  road  surface,  so 
the  car  is  really  pushed 
forward.  Since  it  is  this 
pushing  action  which 
really  moves  the  car  for- 
ward, it  b  very  interest- 
ing to  note  how  thb  push 
is  transmitted  from  the 
wheeb  and  rear  axle  to 
which  they  are  attached 
to  the  frame  which  car- 
ries the  body  and  pas- 
senger load. 

The  transmission  of 
the  drive  to  the  body  is  «    ,.„    rv         .  e   ,  ■   t^  ■     o   ^■ 

""  Fie.  **0-     DiMTUD  to  Eiplun  Dnviiig  Reactiaoa 

accomplbhed   in  one  of  Uiin,  r«uu.  Rod* 

three,  ways.  The  first  form  was  the  so^^Ued  radius,  or  distance, 
rod,  which  the  shaft-driven  car  inherited  from  the  chain^Iriveii  form. 
In  the  chain  drive,  these 
rods  were  a  necessity  and 
served  a  double  purpose; 
they  kept  the  drivbg  and 
driven  sprockets  the 
proper  "dbtance"  apart 
for  correct  chain  driving 
(hence  their  name  "dis- 
tance" rods),  and  they 
alsotransmitted  thedrive 
back  to  the  frame.  On 
the  shaft-driven  car,  the 
dbtance  function  is  not 
needed,  so  they  are  called 
radius  rods.  As  shown 
in  Fig.  440,  they  transmit 
the  drive  forward  to  the  frame,  thus  propelling  the  car  in  the  direc- 
tion of  the  arrow.and  they  also  keep  the  rear  axle  in  its  correct  VQ».ti!QO-< 


Fia.  441.    Uynit 


ca 

^^■^^ 

580                          GA 

SdUNE  AUTOMOBILES               ^^^"^ 

In  liglitening  and  simplifying  the  ahaft-driveti  rar,  dedgners 
figured  tiiat  three  members  for  the  torque  and  driving  reactions  were 
too  many;  30  a.  design  was  worked  out  in  wliich  all  tliree  were  combined 
into  one,  which  is  a  form  of  tube  surrounding  the  shaft.  Tliis  nisde 
the  member  light  but  strong,  and  simplified  the  whole  rear  end.  As 
shown  in  Fig.  441,  the  tul>e  has  forked  ends  at  the  front,  which  are 
connected  to  the  frame  cross-member  in  such  a  way  as  to  absorb  the 
torque  reaction  and  also  to  transmit  the  drive.  The  method  has 
the  further  advantage  of  needing  but  one  universal  joint,  and  that 
at  the  front  end.  Furthennore.  it  gives  a  correct  radius  of  rise  and 
fall  for  the  rear  axle,  since  the  center  of  the  combined  torque  and  drive 
nieml»er  is  also  the  centerof 
the  universal  joint  in  the 
driving  shaft.  In  the  form 
shown  in  Fig.  339  (radius 
rods  not  shown),  the  two 
di0erent  centers  will  be 
mtteil,  the  torque  rod  giv- 
ing a  greater  radius  than 
the    shaft.    Similarly,   in 


GASOLINE  AUTOMOBILES  581 

cars  it  is  gradually  replacing  all  other  forms.  It  has  the  advantages 
of  minimum  weight  and  fewer  parts,  and  applies  the  driving  force  in  a 
direct  line  to  the  frame,  the  same  as  the  two  radius  rods  do.  On  the 
other  hand,  it  makes  the  springs  serve  a  triple  purpose,  the  demands 
on  these  for  torque  and  drive  transmission  and  absorption  being  such 
that  the  spring  flexibility  must  be  negligible,  which  makes  the  car  ride 
hard.  In  addition,  making  the  springs  handle  the  three  widely 
different  actions  puts  additional  stresses  upon  them,  so  that  they  are 
more  likely  to  break.  On  the  medium  size  and  larger  heavier  cars, 
this  construction  is  not  gaining  so  rapidly. 

TYPES  OF  REAR  AXLES 

Classification.  Rear  axles  may  be  divided  into  the  following 
classes,  distinguished  according  to  the  method  of  carrying  the  load  and 
taking  the  drive:  the  form  in  which  the  axle  carries  both  load 
and  drive;  the  semi-floating  form,  carrying  the  drive  and  a  small  part 
of  the  load,  the  axle  shafts  not  being  removable  without  removing 
the  wheels;  three-quarter  floating  form,  carrying  the  drive  and  a  small 
part  of  the  load,  the  latter  being  divided  between  the  shaft  and  its 
housing,  but  with  the  shafts  removable;  seven-eighths  floating  form, 
carrying  the  drive  but  not  the  load,  the  arrangement  of  bearings  to 
take  the  load  being  such  that  the  wheel  hubs  do  not  rest  wholly  and 
solely  upon  the  axle-casing  end;  the  full  floating  form,  in  which  the 
shaft  does  nothing  but  drive,  and  is  removable  at  will  without  dis- 
turbing the  wheel  and  wheel  weight  resting  on  the  axle-casing  end, 
which  is  prolonged  for  this  purpose. 

The  seven-eighths  floating  typp  has  been  developed  to  meet  the 
need  which  arose  for  a  floating  construction,  in  which  the  axle  casing 
did  not  pass  entirely  through  the  wheel  hubs.  With  the  full  floating 
form,  any  accident  to  the  wheel,  in  which  it  was  struck  from  the  side, 
also  damaged  the  casing,  or  tube,  end.  The  result  of  this  in  nine 
cases  out  of  ten  was  to  make  the  removal  of  the  wheel  impossible, 
because  the  tube  end,  which  projected  through,  was  bent  over. 
Moreover,  repwing  in  sudi  a  situation  called  for  a  new  axle  casing 
-^  very  expensive  proposition.  Consequently,  the  seven-eighthf* 
floating  form  was  devdoped  to  present  all  the  advantages  of  the 
full  floating  form,  with  tliis  serious  drawback  eliminatefl  by  a  rear- 
rangement of  the  parts  whidi  did  not  necemiBte  prolonging  the  aidk 


.^    ^ 


IIIMII 


Tfif^»  fmorfrr-  ^7ba///^\ 


ncipal  Fonoft  of  K«ar  Axle 

figures  show  how  the  three-quartc 


GASOUNE  AUTOMOBILES 


to  lubricate,  and  yet  which  was  down  in  the  dust  and  dirt,  so  that 
lubrication  was  a  great  necessity.  All  these  causes,  coupled  with  the 
fact  that  the  axle  carried  both  load  and  drive,  caused  its  disuse. 

Dropped  Rear  Axle  of  Full  Floating  Type.  The  dropped  type 
of  axle  is  not  much  used  at  present  for  cars  of  the  shaft-driven  type, 
the  dropped  part  of  the  axte  bed  being  used  to  hold  the  rearward- 
placed  transmission.    Fig.  444  shows  a  former  American  "type,  in 


Fic.  M4.     R««r  Coniti 


iD  Embodying  Dropped  Type  of  R«r  Aile 


which  the  weight  of  the  car  as  well  as  the  weight  of  the  load  is  carried 
on  the  I-section  drop-forged  rear  axle,  while  the  drive  is  transmitted 
from  the  transmission  by  the  usual  shafts,  which  carry  no  load.  The 
cut  shows  the  complete  assembly  above  and  the  dropped  axle  below. 
The  round  ends  of  the  I-beam  axle  are  hollow,  carrying  the  driving 
shaft  through  the  central  hole  and  the  wheels  on  bearings  which 
fit  over  the  outside.  The  wheels  will  revolve  on  the  bearings,  even 
if  the  inner  shafts  and  transmission  be  removed  from  the  chassis. 
Despite  its  manifold  advantages,  the  expense  of  constructing 
an  axle  of  this  type — it  is  practically  the  same  as  that  of  two  ordfc- 


I  I 


tne  dnve  irom  the  differential  t. 
joints.  The  inevitable  loss  due 
and  to  the  two  joints  in  each  Ii 


fig.  «4S.     Typi™ 

UMng  this  form,  although  a  few 
pany— have  inserted  a  pair  of  joi 
rear  wheels  the  same  camber  as  ( 


GASOLINE  AUTOMOBILES 


585 


i  external  notches,  or  jaws,  to  correspond  with  the  teeth,  but 
lally  it  is  more  of  a  claw  type,  the  dri^-ing  ends  projecting  inward 
m  the  point  of  attachment  to  the  axle  shaft.  Another  notable 
nt  of  difference — and  one  which  makes  a  huge  difference  in  the  cost 
ies  in  the  machining  of  these  jaws,  whether  they  are  attached  to  the 
e  or  machined  up  with  it  in  one  piece.  The  latter  is  considered 
:ter  and  stronger  in  every  way,  but,  as  it  is  much  more  expensive, 
s  used  only  on  the  best  cars. 

The  driving  clutch  takes  various  forms,  one  of  which  is  shown 
the  Studebaker  axle.  Fig.  445.  In  this  type,  the  axle  is  a  square 
I  acting  within  a  square  hole  in  the  hubs.  In  the  small  detail  at 
:  upper  left-hand  corner  the  letter  A  shows  the  square  upon  which 
;  driving  clutch  is  slipped.  The  spaces  at  the  inner  ends  of  this 
icate  the  clutches,  or  jaws,  which  mesh  with  corresponding  slots 
the  wheel  hub  and  thus  do  the  driving. 


iog  Wheels  Driven  by  Spur  Ceu 


The  dropped  type  of  axles  are  neither  all  shaft-driven  nor  all 
lin  driven.  Fig.  446  shows  one  that  is  of  the  spur-gear  driven 
ie.  The  dropped  axle  bed  C  is  of  tubular  form,  and  the  differ- 
ial  case  is  dropped  down  on  and  slightly  back  of  the  rear  axle,  as 
"B.  From  this  case,  two  shafts  A  A  extend  out  to  the  sides,  driv- 
the  wheels  through  the  medium  of  the  spur  gear  D,  which  meshes 
h  internal  gears  within  the  wheel  hubs  (not  shown) .  This  type  of 
r  axle  and  drive  is  used  on  a  number  of  the  Fifth  Avenue  stages 
Sew  York  City. 

Internal-Qear  Drive  for  Trucks.  The  spur-gear  driven  type 
t  described  is  gaining  rapidly  for  motor-truck  use,  because  it  has  a 
nber  of  important  advantages.  Besides  carrying  the  heavy  load 
a  member  able  to  withstand  any  amount  of  overload,  it  materially 
itens  the  power-transmitting  portion  of  the  axle,  which  is  enclosed 
1  therefore  quiet.  It  is  simple  and  inexpensive  to  construct  and 
air.    Fig.  447  shows  a  section  through  one  of  these  axles,  which  is 


GASOLINE  "AUTOMOBILES 


the  driving  clutches  machined  as  an  integral  part,  and  that 
)\nng  the  two  shafts  for  a  few  inches  makes  it  possible  to  unbolt 


Fig.  41S.     Elaniplc  o[  Full  Flun 


Fix    44!).     Timki-n  Kiill  Fluating  Ut:i 


remove  the  entire  difFerential  uijit-  For  tlie  siikc  uf  compari- 
Fig.  45(»  shows  an  axle  whicli  dilTers  from  Fig.  449  only  In  having 
i  bevels  substitute*!  for  the  ordinary  straight-tooth  bevels.    In 


design  is  seen  in  Fig.  431.    Tl 


it  dilTers  fn)ni  pre\iously  destr 
floating  t.\pe.  Note  the  cncltis 
at  its  forward  pIwI  fur  th^  i.n;.-= 


GASOLINE  AUTOMOBILES  589 

on  the  same  drum,  with  operating  shafts  for  both  supported  from  the 
central  part  and  ends  of  the  axle  housing. 

Rear-Axle  Housings.  Rear-axle  housings  are  usually  of  pre3sed 
steel,  although  castings  play  a  very  important  part  and  are  some- 
times used  alone  and  sometimes  in  combination  with  other  castings  or 
in  combination  with  pressed  steel.  Aluminum,  although  not  a  depend- 
able metal,  is  used  quite  a  good  deal  for  the  purpose  of  saving  weight, 
as  excess  weight  upon  the  rear  axle  is  anything  but. desirable.  In 
one  unusual  but  effective  combination,  the  axle  housing  consists 
of  two  malleable-iron  castings  joined  together  by  means  of  bolts  at 
the  centers,  the  brake  drums  being  cast  as  a  part  of  the  tubes.  While 
not  usual,  this  is  safe  practice,  for  malleable  iron  is  tough  and  will 
not  break  or  splinter.  It  seldom  is  the  case,  however,  that  the  axle 
casing  is  reduced  to  as  few  parts  as  are  shown  here. 

Welding  Resorted  To.  Where  the  differential  housing  or  brake 
drums  are  of  malleable  iron,  cast  steel,  or  even  of  pressed  steel,  and  it 
is  desired  to  unite  them  with  the  steel  tubing  forming  the  main  part 
of  the  shaft  housing,  welding  is  now  universally  used.  Formerly, 
it  was  good  practice  to  make  the  casing  a  drive  fit  on  the  tube,  riveting 
it  in  place,  or  else  soldering  it  in  place,  making  doubly  sure  by  using 
rivets.  Now,  however,  welding  is  resorted  to,  either  the  oxy- 
acetylene,  electric,  or  some  other  process  being  used. 

In  the  axles  shown  in  Figs.  449  and  450,  it  will  be  noted  that 
the  axle  shell  is  of  pressed  steel,  to  which  the  spring  seats  are  bolted, 
the  remainder  of  the  construction  being  formed  by  drawing.  In  Fig. 
448,  however,  the  construction  is  such  as  to  necessitate  making  the 
two  halves  longitudinally  and  then  bolting  or  spot-welding  them 
together.  Being  machined  after  they  are  fastened  together,  it  makes 
as  accurate  a  construction  as  the  one-piece  jobs.  Figs.  449  and  450. 

Effect  of  Differentials  on  Rear  Axles.  A  differential  gear, 
sometimes  called  a  balance,  or  compensating,  gear,  is  a  mechanism 
which  allows  one  wheel  to  travel  faster  than  the  other  and  which 
at  the  same  time  gives  a  positive  drive  from  the  engine.  This  device 
is  a  necessity  in  order  to  allow  the  car  to  go  around  a  curve  properly, 
for  in  doing  so  the  outer  wheel  must  travel  a  greater  distance  than 
the  inner  one  during  the  same  interval  of  time. 

There  are  two  forms  of  differential,  the  bevel  type  and  the  all-spur 
tj'pei'the  latter  differing  from  the  former  only  in  the  use  of  spiw  gears 


(lASOLINE   AUTOMOBILES 


instead  nf  hcvrl  fjciirs.  The  principle  used  in  both  is  that  a  set  of 
gears  are  ^o  lieM  tij>;etlier  that  when  a  resistance  comes  upon  one 
part  of  the  train  nf  gears  the  whole  train  will  stop  revolving  around 
on  a  stafinnary  axis  anil  revolve  around  another  gear  as  an  axis,  the 
first  gear,  in  the  meantime,  standing  stationary,  or  practically  so, 
according  tn  the  amount  of  the  resistance  encountered.  In  the 
bcvol  tyi)e,  a  pair  of  Iwvels  are  set  horizontally.  Between  the  bevels 
is  a  spiHtT  with  thn-e  or  fiiur  arms,  with  a  small  bevel  on  the  end  erf 
each.  These  ■^uy,\\\  ln've!s  mesh  with  the  larger  bevels  at  the  sides 
and  ordinarily  stand  still,  ro- 
tating around  on  the  arm  o( 
the  spider  as  an  axis  by  virtue 
of  the  continued  rotation  of 
the  two  side  gears  in  opposite 
directions.  When  one  whed 
meets  greater  obstructions  on 
the  road  than  the  other,  thus 
holding  it  back,  the  stiaft  I 
which  drives  that  wheel  lags 
behind  the  shaft  driving  tlic 


GASOLINE  AUTOMOBILES  591 

would  permit  the  differential  action  and  still  allow  the  strengthening 
of  the  rear  axle.  Fig.  452  shows  one  solution  of  the  problem,  which 
has  been  worked  out  in  such  a  way  that  the  differential  is  moved 
forward  into  the  driving  shaft.  The  rear  axle  shafts  are  thus  greatly 
strengthened,  the  designer  being  unhampered  by  the  presence  of  the 
differential  in  the  rear  axle.  In  this  design,  one  side  gear  of  the  bevel- 
gear  differential  is  carried  upon  a  shaft,  and  the  other  upon  a  tube 
around  the  shaft.  Thoji,  at  the  rear  axle,  two  sets  of  bevel  gears 
BiBz  and  AiA^  are  used,  Ai  being  driven  by  the  main  shaft,  and  driv- 
ing the  right-hand  shaft  through  the  gear  A2;  while  the  other  B^  is 
driven  by  the  tube,  and  drives  the  left-hand  shaft  through  the  gear  B^. 
In  this  case  the  axle  shafts  are  made  much  larger  than  in  the  ordinary 
case,  while  the  differential  action  is  just  the  same. 

Improved  Forms  of  Differential.  Lately,  much  work  has  been 
done  upon  differentials  to  cause  them  to  act  as  differentials  should. 
The  present  form  of  differential  acts  according  to  the  amount  of 
resistance  offered,  but  should  act  according  to  the  distance  traveled. 
When  no  resistance  is  offered,  all  the  power  is  transmitted  to  that 
wheel,  leaving  the  other  stationary.  This  is  just  the  opposite  of  the 
desired  effect.  If  a  differential  Were  constructed  to  work  for  distance 
only,  then,  in  the  case  of  a  wheel  on  ice  or  other  slippery  surface  which 
offered  little  or  no  resistance,  both  wheels  would  still  be  driven 
equally,  and  the  power  transmitted  to  the  one  not  on  the  ice  would 
pull  the  vehicle  over  it. 

One  way  in  which  the  differential  action  might  be  corrected  is 
by  the  use  of  helical  gears  and  pinions  instead  of  the  usual  bevel  or 
spur  gears.  In  the  M  &  S  forms,  this  construction  is  used.  Fig.  453, 
showing  the  form  constructed  by  Brown-Lipe-Chapin.  In  this  form, 
each  axle  shaft  carries  a  helical  gear,  and  the  differential  spider  carries 
two  helical  pinions  with  radial  axes  and  four  additional  pinions,  each 
of  which  meshes  with  one  of  the  radial  pinions  and  one  of  the  gears 
on  the  axle  shafts.  On  a  turn,  the  outer  wheel  tends  to  run  ahead 
of  the  inner  and  thus  causes  the  nest  of  helical  gears  to  revolve.  All 
gears  and  pinions  have  a  right-hand  45-degree  tooth,  so  that  one  wheel 
may  revolve  the  housing  if  the  other  is  locked  or  held,  but  it  is  impos- 
sible to  turn  the  free  road  wheel  by  pulling  on  the  housing.  The 
principle  is  the  same  as  a  worm  steering  gear  in  which  the  turning  of 
the  hand  wheel  may  be  transmitted  to  the  front  wheels,  but  the  gear 


5!t2 


CJASOLINE   AUTOMOBILES 


n  tlie  wheel  end,  because  the  worm  If 

is  usetl  to  advantage  to  prevent  spinning  on 

i>  tu  eliminate  the  skidding  which  the  ordinary 


canniit  l)e  operated  froi 
ihle.  Tliis  .IiHVr.>i.tiiil 
slippery  ftroiirnl  and  als 
(UlVcrentiiilKives. 

Aniitlier  .si>niewliat  similar  device  has  but  two  pairs  of  helical 
pinions  tri  adiiition  to  tlie  two  hehcal  gears  on  the  shafts,  the  axes  of 
eaeh  pair  beiii^'  set  at  an  angle  to  the  others.  Thus,  each  helical 
gear  and  ils  pinion  form  an  irreversible  gear  combination,  so  that 
niovemciit  earnint  be  transmitted  through  either  in  the  reverse  direc- 
tion. Tliis  form  fulfills  the  same  conditions  as  the  Brown-Lipe- 
Cliapin  M  &  H  form,  as  the  construction  is  such  that  no  motion  can  be 


GASOLINE  AUTOMOBILES 


593 


forward.  On  a  turn,  one  wheel  revolves  faster  than  the  other,  say 
the  right,  and  causes  the  right-hand  ratchet  to  move  faster  than  the 
differential  housing,  which  can  only  go  as  fast  as  the  other,  or  slow- 
moving,  wheel.  Then,  the  right-hand  ratchet  pushes  the  end  of 
its  pawl  out  of  the  tooth  and  gives  it  a  free  movement  forward.  As 
soon  as  the  wheels  revolve  at  equal  speeds,  the  spring  pushes  it  back. 
In  the  figure,  the  right-hand  portion  shows  the  original  form  in 
perspective. 

Poaaible  Elimination  of  Differential.  The  whole  modem  tend- 
ency is  toward  differential  elimination.  In  the  cyclecars  and  small 
ears  brought  out  in  recent  years,  designers  have  been  forced  to  get 


F!(.  154.    Sketches  Showing  Constnictiou  kod  Op6TBtion  of  Gnrlm  Dinnentlal 

along  without  it  because  of  the  demand  for  simplicity,  light  weight, 
and  low  price.  This  effect  has  been  obtained  by  the  use  of  a  pair  of 
driving  belts,  letting  one  slip  more  than  the  other;  by  the  use  of  fric- 
tion transmissions;  by  simply  dividing  the  rear  axle  and  letting  one 
side  lag  when  there  was  resistance;  by  not  dividing  it  and  letting 
one  wheel  drag;  and  in  other  ways.  The  evident  success  of  these 
small  vehicles  without  a  differential  or  any  real  substitute  for  one 
has  set  designers  to  thinking  about  this  subject  again,  and  some 
big  cars  without  a  differential,  or  with  a  more  simple  and  less 
expensive  substitute  for  it,  may  appear  in  the  near  future. 

Rear-Wheel  Bearings.    The  bearings  used  on  rear  axles  differ 
very  littlo  from  tiiose  used  on  front  axles.    All  forms  are  used — plain 


,W4  CASOLINE  AUTOMOBILES 

liearinps.  ball  hciirinj;s,  hiiW  thrusta,  roller  bearings  in  both  cylindrical 
itiid  tapered  typca,  aiul  all  combinations  of  these.  Thus,  Figs.  445 
iinii  452  sliovv  tlie  exclusive  and  liberal  use  of  ball  bearings,  while  Fig. 
■iry]  slinws  all  rnllers  of  two  kinds  and  ball  bearings  for  thrust  bear- 
ings f^i'ly.  'i'lie  two  kiixls  of  roller  bearings  are  the  tapered  roller  and 
tlie  flexible  roller.  Similarly,  in  Fig.  447,  It  will  be  noted  that  balls 
are  nsnl  n  itli  two  kinds  of  rollers,  straight  solid  rollers  in  the  wheels 
ami  flexible  rollers  in  the  dilTerential  case.  Figs,  449  and  450  show 
the  exclusive  use  of  the  tapered  roller  type,  a  construction  which  is 
gaining  gnniiid  very  rapidly,  the  same  as  in  front  axles,  although, 
formerly,  ball  bcarinfts  were  most  widely  used.  The  materials 
employed  are  similar  to  those  used  for  front  axles,  which  have  been 
l)revi(>usly  described.  Cases  are  made  of  all  kinds  of  steel  and  iron — 
pressed,  drawn,  east,  ete. — not  to  speak  of  crueihle  steel,  malleable 
iron,  niaii);aiiese  Imiiize,  phosphor  bronze,  aluminum,  aluminum 
alloys,  and  many  eumbiiiations  of  these  materials  in  twos  and  threes. 
Rear=Axle  Lubrication.  Rear-axle  lubrication  Is  generally 
autoinutic  in  so  far  as  the  central  bevel  or  other  gears  and  the  differ-, 
ential  lionsiiiK  are  ciinccrned.    The  housing  usually  has  a  form  of- 


GASOLINE  AUTOMOBILES  595 

necessary  to  remove  the  shaft  alon^.  In  almost  all  cases,  the  axle 
must  be  jacked  up.  Many  axles  have  a  truss  rod  under  the  center, 
and  this  is  in  the  way  when  jacking;  however,  this  can  be  overcome. 
Make  from  heavy  bar  iron  a  U-shaped  piece  like  that  shown  on 
top  of  the  jack  in  Fig.  455,  making  the  width  of  the  slot  just  enough 
to  admit  the  truss  rod.  The  height,  too,  should  be  as  little  as  will 
give  contact  with  the  under  side  of  the  axle  housing. 

Substitvie  for  Jack.  A  good  substitute  for  a  jack  is  a  form  of 
hoist.  Fig.  456,  which  will  pick  up  the  whole  rear  end  of  the  car  at 
once.  This  not  only  saves  time  and  work,  but  holds  the  car  level, 
while  jacking  one  wheel  does  not.  Moreover,  with  a  rig  of  this  kind, 
the  car  can  be  easily  lifted  so  high  that  w;ork  underneath  it  may  be 
easily  done.  The  usual  hoisting  blocks  are  very  expensive,  but  the 
above  hoist  can  be  easily  made  by  the  ingenious  repair  man.  This 
one  was  made  from  an  old  whiffletree  with  a  chain  attached  at  each 
end.  For  the  lower  ends  of  the  chains,  a  pair  of  hooks  are  made 
sufficiently  large  to  hook  under  and  around  the  biggest  frame  to  be 
handled.  With  the  center  of  the  whiffletree  fastened  to  the  hook  of 
a  block  and  tackle,  the  hoist  is  complete.  By  slinging  the  hooks 
under  the  side  members  of  the  frame  at  the  rear,  it  is  an  easy  matter 
to  quickly  lift  that  end  of  the  chassis  any  distance  desired. 

Workstand  Equipment.  Next  to  raising  the  rear  axle,  the  most 
important  thing  is  to  support  it  in  its  elevated  position.  To  leave  it 
on  jacks  is  not  satisfactory,  for  they  will  not  raise  the  frame  high 
enough,  and,  furthermore,  they  are  shaky  and  may  easily  let  the  whole 
rear  end  fall  over,  doing  considerable  damage.  With  the  overhead 
hoist,  the  chains  or  ropes  are  in  the  way;  so  a  stand  is  both  a  necessity 
and  a  convenience.  In  Fig.  457,  several  t\T)es  of  stands  are  shown.  A 
is  essentially  a  workstand,  intended  to  hold  the  axle  and  part  of  the  pro- 
peller shaft  while  repair  work  is  being  done  thereon.  It  consists  of 
a  floor  unit,  or  base,  built  in  the  form  of  an  A,  with  six  uprights  let 
into  it,  preferably  mortised  and  tenoned  for  greater  strength  and 
stiffness.  Then,  the  four  rear  uprights  are  joined  together  for  addi- 
tional stiffness  and  rigidity.  If  casters  are  added  on  the  ends,  the 
stand  can  be  more  conveniently  handled  around  the  shop. 

.  The  forms  B  are  for  more  temporary  work  and  consequently 
need  not  be  so  well  or  so  elaborately  made.  The  little  stand  C  is  a 
very  handy  type  for  all-around  work.    Stands  of  this  kind  with  the  * 


r>ii6 


GASOLINE  AUTOMOBILES 


top  surface  j;roo\Td  for  the  axle  are  excellent  to  place  under  cars 
wliicli  liiive  hi'vn  put  in  storage  for  the  winter. 

Till-  staiiil  Jl  is,  liki-  A,  a  workstami  pure  and  simple.     In  this, 
howi'vcr,  the  i!roppi.'d-(.'nd  members  allow  supporting  the  axle  at 


GASOLINE  AUTOMOBILES  597 

the  dirt  and,  consequently,  lessen  the  wear,  and  also  lubricate  the 
moving  parts  of  the  joints.  A  secondary  function  of  the  casings  is  to 
render  these  joints  noiseless.  If  a  car  is  not  equipped  with  them,  it  is 
advisable  for  the  owner  to  purchase  them. 

The  shape  of  these  casings,  when  opened  out  flat,  would  be  not 
unlike  that  of  two  bottles  with  their  flat  bottoms  set  together,  that 
is,  narrow  at  the  top  and  bottom  and  n-ider  at  the  middle.  All  along 
both  edges  are  eyelets  for  the  lacing.  The  enlarged  center  fits  around 
the  joint,  while  the  small  ends  encircle  the  respective  shafts.  To  apply 
the  casing,  one  end  is  placed  around  the  shaft  on  one  side  of  the  joint, 
and  the  lace  started;  then  the  lacing  proceeds,  gradually  drawing 
the  ends  together  and  around  the  joint.  When  this  has  been  com- 
pleted, and  before  the  last  end  is  closed,  the  whole  is  shoved  back 
along  the  first  shaft  a  little  way,  and  the  center  portion  half  filled 
with  a  heavy  grade  of  transmission  grease.  This  done,  the  glove  is 
pulled  back  into  place,  and  the  work  of  lacing  completed  around  the 
second  shaft.  Both  ends  should  be  laced  as  tightly  as  possible,  while 
the  middle  part  should  be  loose.  Sometimes  these  housings  will 
become  worn  and  make  a  very  annoying  chatter  on  the  road,  even 
when  they  are  not  sufficiently  worn  to  warrant  replacements.  Under 
such  circumstances,  the  offending  member  may  be  wound  with  tire 
tape  held  firmly  in  place  in  addition  to  its  adhesive  power  by  means  of 
a  hose  clamp,  as  shown  in  Fig.  458.  The  coupling  is  held  tightly 
enough  to  prevent  the  rattle  and  chatter,  but  not  enough  to  interfere 
with  its  action.  While  not  a  handsome  job,  it  does  the  business, 
stopping  the  noise  effectively. 

Rear  Axle.  Rear  axles  do  such  hard  work  and  must  stand  up 
under  such  a  large  portion  of  the  load  carried  in  the  machine  that 
they  offer  many  chances  for  wear,  adjustment,  or  replacement. 

Truss  Rods.  Truss  rods  hold  the  wheels  in  their  correct  ver- 
tical relation  to  the  road  surface  and  to  one  another.  If,  through  wear 
or  excessive  loading,  the  axle  sags  so  that  the  wheels  tip  in  at  the 
top,  presenting  a  knock-kneed  appearance,  the  truss  rods  must  be 
tightened  up.  Usually,  they  are  made  with  a  turnbuckle  set  near  one 
end,  a  locknut  on  each  side  preventing  movement.  The  turnbuckle 
is  threaded  internally  with  a  right-hand  thread  on  one  end  and  a  left- 
hand  thread  on  the  other,  so  that  a  movement  of  the  turnbuckle  draws 
the  two  ends  in  toward  one  another,  shortens  the  length  of  the  rod. 


GASOLINE  AUTOMOBILES 


and  thus  piills  the  lower  parts  of  the  wheels  toward  one  another, 
furrecting  the  tippiug  at  the  top. 

To  adjust  a  siiRgiiig  axle,  loosen  !H>th  loeknuts,  remembering 
that  one  is  riKht-hiindoH  and  the  other  left.  Then,  with  the  wheels 
jacked  Hear  of  the  ground,  tighten  the  turnbuekle.  A  long  square 
should  be  procured  or  made  so  that  the  wheel  inehnations  may  be 
measured  before  and  after.  Placing  the  square  on  the  ground  or 
floor,  which  should  he  selected  so  as  to  be  perfectly  level,  the  turn- 
buckle  should  he  moved  until  the  tops  appear  to  lean  outward  about 
i  inch — some  makers  advise  more. 

It  should  be  borne  in  mind  that  even  if  the  wheels  and  axle  do 
not  show  the  need  of  truss  rod  adjustment,  if  this  rod  be  hK)se,  it 
will  become  very  noisy  and  rattle  a  great  deal,  as  the  rear  axle  sus- 
tains a  great  amount  of 
jouncing.  Moreover,  this 
noise  and  rattle,  if  not 
taken  up,  wilt  cause 
which  cannot  be 
taken  up. 
.     Dita^setubling    Rear 


■1.  "ja  j.iP*w<i>*ne»^gfja  _ 


GASOLINE  AUTOMOBILES  599 

then  disconnect  the  spring  bolts  and  jack  up  the  chassis,  using  the 
spring  for  a  support.  Disconnect  all  torsion  or  radius  rods  and  take 
off  the  grease  boot  around  the  universal  joint  in  the  driving  shaft. 
Open  tliis  joint  and  disconnect  the  shaft.  Take  this  off,  and  if  the 
spring  bolts  have  been  removed,  the  rear  axle  will  be  free.  Pull  it 
out  from  under  the  chassis,  and,  if  desired,  further  disassembling  may 
be  done  more  easily  with  the  member  clamped  in  a  vice  or  laid  on  a 
bench. 

Assembling.  In  assembling,  almost  the  reverse  of  this  process 
is  followed,  the  parts  going  together  in  the  opposite  manner  from 
that  in  which  they  were  taken  down. 

Noisy  Bevel  Gears.  If  the  bevel  gears  in  the  rear  axle  are 
noisy,  the  time  to  fix  them  is  when  the  axle  is  disassembled,  as  this 
is  quite  a  job.  In  general,  bevel  gears  make  a  noise  because  they 
are  poorly  cut,  because  they  are  not  set  correctly  with  relation  to 
each  other,  or  because  the  teeth  have  become  cut,  or  chipped,  by 
some  foreign  material  which  has  been  forced  between  them. 

In  the  first  case,  there  is  little  the  amateur  can  do  bevond 
making  the  best  possible  adjustment  and  smoothing  off  any  visible 
roughness.  In  the  second  case,  it  is  simply  a  matter  of  setting  one 
gear  closer  to  ot  farther  from  the  other  by  means  of  the  adjustment 
provided.  When  the  axle  is  disassembled,  and  all  parts  are  readily 
accessible,  it  will  be  found  that  there  is  a  notched  nut  on  either  side 
of  each  of  the  bevels;  there  should  be  a  wrench  in  the  tool  kit  to  fit 
this.  It  is  then  a  simple  matter  to  move  one  outward  and  the  other 
inward  in  either  pair,  according  to  which  needs  the  adjustment. 
In  case  the  teeth  have  become  chipped,  the  projections  should  be 
smoothed  down  with  a  fine  file,  while  the  sharp  edges  of  the  cuts 
should  be  dressed  in  the  same  manner. 

Packard  Bevel  Adjustment.  Although  strictly  a  transmission 
trouble,  the  older  Packard  cars  have  the  transmission  located  on  the 
rear  axle,  and  this  position  made  the  adjustment  of  the  bevel  pinion 
difficult.  For  another  thing,  the  shaft  is  very  short  and  hard  to  hold. 
If  the  sliding  gear  on  the  shaft  is  meshed  with  the  internal  gear 
attached  to  the  other  end  of  the  bevel-pinion  unit,  the  latter  will  hold 
firmly,  but  there  will  still  be  a  little  play  between  the  teeth.  It  is 
necessary  to  take  this  up,  as  otherwise  the  repair  man  would  mistake 
this  play  for  play  in  the  bevel  driving  gear.    It  can  be  taken  up  as 


CA^JOLINE  AUTOMOBILES 


ms:  Tiiki'im  oM  ^liilinp-gear  unit  from  one  of  these  transmissions, 
(ive  uiR'  nl'  till'  tt'ctli  iiivi  slide  the  gear  into  position  for  meshing 
I  tilt-  .spjRv  Jit  till'  to])  between  two  teeth  on  the  good  gear.  Drive 
n  in  wliere  the  tooth  has  been  removed,  and  this  will  fix  the  two 
ily  tiiKftlier  witliout  a  particle  of  play.  Then,  by  removing  the 
IT  from  tlif  (iill'iTL-ritial  housing,  the  bevels  can  be  tested  for  play. 
4."iil  shdws  thf  transmission,  bevel  gears,  and  axle  parts,  also  the 
-  with  tlie  tooth  removed  and  replaced  by  a  pin,  so  that  the  whole 


vill  1; 


clear 


HriKiirfiir  liruhii  Spring  Clija.    The  springs  are  held  down  on 
jixli's  l)y  nifaiis  of  spring  clips,  which  are  simply  U-shaped  bolts 


GASOLINE  AUTOMOBILES 


601 


Limng  Up  Axles.  In  such  a  repair,  however,  the  main  thing 
to  get  the  rear  axle  lined  up  correctly,  which  is  not  an  easy  job. 
lis  may  be  done  in  the  following  manner:  Get  the  car  standing  level 
a  nice  clean  smooth  floor;  hold  a  large  metal  square  with  a  plumb 
b  hanging  down  over  its  short  edge  against  the  side  of  the  frame, 
ove  the  square  forward  until  the  line  ju.st  touches  the  rear  axle  at 
me  set  distance  out  from  the  frame,  say  .3  inches,  as  shown  in  Fig, 
1.  Then  notice  the  distance  this  line  is  forward  from  the  rear  end 
the  frame.  In  the  sketch  it  is  16  inches.  Transfer  the  square  and 
jmb  bob  to  the  other  side  and  repeat.  Here  it  will  be  found  that  the 
itance  from  the  rear  end  of  the  frame  is  either  more  or  less.  In  the 
etch  it  is  shown  at  18  inches;  so  the  difference,  2  inches,  shows  that 
e  axle  is  out  of  alignment 
at  much  or  half  that,  1 
•h  at  each  end. 

Thb  axle  is  straightened 
loosening  the  spring  bolts 
d  pushing  one  side  back 
e  distance  apparently 
eded,  then  fastening 
;htly  and  checking  up.  If 
t  correct,  try  again,  using 
dgment  as  to  which  side 
ould  be  moved.  When 
lally  satisfied  that  the  rear 
le  is  square  with  the  frame, 
is  well  to  checis  this  against  the  center-to-center  distance  of  the 
leels  on  each  side.  This  is  done  by  setting  the  front  wheels  exactly 
'aight  and  then  measuring  from  the  center  of  the  right  front  to  the 
nter  of  the  right  rear  wheel.  Then  go  over  to  the  other  side  and 
;asure  the  center-to-center  distance  of  the  left  wheels.  The  two 
les  should  agree  exactly.  If  they  do  not,  the  rear  axle  prusumably 
eds  more  adjustment  for  squareness. 

Taking  Out  Bend  in  Axle.  A  simple  method  of  repairing  an  axle 
lich  has  been  bent,  hut  a  method  which  is  only  temporary  in  that  it 
not  accurate  enough  to  give  a  job  which  could  be  called  final,  is 
at  indicated  in  Fig.  462.  The  axle  was  bent  when  the  hub  struck 
obstruction  in  the  road,  and  it  had  to  be  straightened  immediately. 


B  Clipa  Are  RepUeed 
Motor  World" 


CAt^OLINE  AUTOMOBILES 


A  short  IciiRth  i>f  2  x  4  timber  was  cut  to  be  a  tight  fit  between  the 
upper  silk'  iif  tlit'  liiib  citp  iind  the  roof  beam.     Then  a  jack  under  the 


°7 


0 

■  and  Plmub  Bob 


mI'  till'  iniul  was  raised.     As  the  jack  raised  the  axle, 

tiii  licld  the  hub  down,  enough  pressure  was  exerted 

toforce the  axle  to  give  st  the 

bend  and  return  as  nearly  as 

possible  to  its  original  straight- 


GASOLINE  AUTOMOBILES 

ime,  and  was  sure  that  the  bevel  gears  were  out  f 
irere  cutting  each  other.     It  was  a  low-pitched/ 
lot  apparent  at  low  speeds,  but  began  to  be  hei 
liles  an  hour,  and  at  times  was  very  apparent, 
nnoyiiig,  but  tearing  down  the  rear  construction  showw 

0  trouble;  so  the  noise  could  not  be  at  that  point.     Sometimfr 
he   noise   was   definitely   located   in    a   pair  of  worn  speedomet^h 
ears  on  the  right  end  of  the  front  axle. 

A  good  way  to  listen  to  rear  axle  hums  out  on  the  road  is  to>lay 
<ack  over  the  rear  end  of  the  car,  Fig.  463,  with  the  head  against 
he  top  of  the  seat  and  project- 
ig  over  slightly,  and  witlr  the 
ands  cupped  in  front  of  the 
ars,  so  as  to  catch  every  noise 
hat  arises.  The  larger  sketch 
hows  the  general  scheme,  the 
mall  inset  giving  the  method 
<f  holding  the  hands.  When 
he  sound  arising  from  the  axle 
i  a  steady  hum,  the  gears  are 
II  good  condition  and  well 
djusted.  If  this  sound  is  inter* 
upted  occasionally  by  a  sharper, 
.arsher  note,  it  may  be  assumed 
hat  there  is  a  point    in   one 

1  the  gears  or  on  one  of  the 
hafts  where  things  are  not  as  they  should  be.  By  trying  the  car 
t  starting,  slowing  down,  running  at  various  speeds,  and  coasting, 
his  noise  can  be  tied  to  something  more  definite,  some  fixed  method 
f  happening.  In  advance  of  actual  repair  work,  including  tearing 
own  the  whole  axle,  the  gears  can  be  adjusted.  This  can  generally 
•e  done  from  outside  the  axle  casing  and  without  a  great  deal  of  work, 
f  the  adjustment  makes  matters  worse,  it  can  be  reversed,  or  if  it 
nproves  the  situation,  the  adjusting  can  be  continued,  a  little  at  a 
ime,  until  the  noise  gradually  disappears. 

Checking  Up  Ford  Axles.  Many  ca.ses  of  ForrI  bent  rear  axles 
an  be  fixed  without  taking  down  the  whole  construction.  The  prin- 
ipal  point  is  to  find  out  how  much  and  which  way  the  axle  is  bent. 


RcAT-Axle  Koiiea 


002  GASOLINK   AUTOMOBILKS 

Ay  rfnidv'mjt  tlic  wliccl  on  the  bent  side  ami  placing  the  rig  shown  io 
I''ig.  4I>4  on  the  axie  eiifl,  the  extent  of  the  trouble  can  be  indicated  by 
the  axle  itself.  The  iron  rod  is  long  and  stifT,  with  its  outer  end 
pointed,  and  is  fastened  permanently  to  an  old  Ford  hub.  The 
rig  is  placed  on  the  axle  and  held  by  the  axle  nut,  but  without  the 
key,  as  the  axle  mn.st  lie  free  to  turn  inside  the  hub.  With  the  pointed 
end  of  the  rod  re-;tirig  on  the  floor  and  with  high  gear  engaged,  have 
some  one  turn  the  engine  over  slowly,  so  as  to  turn  the  axle  shafi 
around.  As  it  revolves,  the  hub  will  be  moved,  and  the  pointed  end 
on  the  floor  will  indicate  the  extent  of  the  bend.  By  marking  the 
two  extreme  points  and  dividing  the  distance  between  them,  the 
center  is  fmind.  'i'lien  a  rod  can  be  used  as  a  bar  to  bend  the  axle, 
until  the  pointed  md  end  is  exactly  on  the  center  mark.  A  little 
practice  with  this  rig  will 
enable  a  workman  to 
straighten  out  a  Ford  rear 
axle  in  about  the  time  it 
takes  to  tell  it. 


GASOLINE  AUTOMOBILES  60S 

Engine  as  a  Brake.  Although  disregarded  in  any  summary  of 
brakes,  the  engine  is  the  best  brake  possible,  granting  that  the  driver 
knows  how  to  get  the  best  results  without  doing  any  damage.  The 
ordinary  engine  has  a  compression  of  from  60  pounds  to  70  pounds  per 
square  inch,  which  is  practically  the  pressure  available  when  it  is  used 
as  a  brake.  Since  this  is  more  pressure  than  any  other  type,  or  form, 
of  brake  will  yield,  its  usefulness  is  self-evident. 

Qassification.  Brakes  are  usually  divided  into  two  classes, 
differing  mainly  in  location — the  internal  expanding  and  the  e:(temal 
contracting.  To  these  a  third  class  should  be  added,  because  it  par- 
takes of  the  nature  of  both,  yet  differs  from  each  one.  This  is  the 
railway  type  of  brake  with  removable  sho^s  of  metal,  dilTering  from 
the  band  t.vpe  in  that  no  attempt  is  made  to  cover  the  whole  or  even 
the  greater  part  of  the  circular  surface,  but  simply  a  smalt  portion  of  it, 
against  which  a  shoe  is  forced  with  a  very  high  pressure.  Both  the 
other  types  are  subject  to  division  into  other  classes,  the  first  into 
three  subdivisions  according  to  operating  means,  viz,  cam,  toggle,  and 
scissors  action. 

Brakes  are  generally  divided  according  to  their  location,  as  shaft 
and  rear  axle.  The  shaft  brake  at  one  time  virtually  went  out  of  use, 
but  it  is  now  being  revived.  The  marked  swing  toward  the  unit 
power  plant,  together  n-ithitssimpHfication,  lightening, and  elimina- 
tion tendencies,  has  produced  a  situation  where  a  brake  drum  just 
back  of  the  power  and  gear  unit  can  be  operated  by  the  hand  lever 
and  a  very  short  rod.  In  this  way  much  weight  and  many  parts  are 
saved.  An  indirect  advantage  is  that  the  brake  is  more  accessible. 
With  the  worm  drive,  there  is  a  marked  tendency  back  to  the  shaft 
brake,  particularly  on  motor  trucks.  Again,  in  the  last  few  years, 
some  work  has  been  done  with  pneumatic,  hydraulic,  and  electric 
forms  of  brake.  With  air  under  pressure  for  starting,  and  with  water 
or  electricity  as  needed  for  starting  or  for  other  purposes,  it  is  a  simple 
matter  to  utilize  the  same  agency  for  braking,  providing  such  use  does 
not  add  too  much  complication  and,  at  the  same  time,  that  it 
will  give  a  superior  method  of  snubbing  the  forward  movement  of  the 
car.  In  case  none  of  these  advantages  are  realized,  there  will  be  no 
particular  advantage  in  adding  new  forms  of  brake. 

External-Contracting  Brakes.  This  class  of  brakes  is  divided 
□to  but  two  types,  viz,  single-  and  double-acting.    In  the  first,  an 


f/n) 


GA.SOLINE  AUTOMOBILES 


enii  uf  a  simple  bumi  is  utithored  at  some  external  point,  while  the 
ntlier.  or  free  end.  is  pulled.  This  results  in  the  anchorage  sustaining 
as  much  pull  as  is  given  to  the  of)erating  end,  that  is,  all  pull  is  trans- 
mitted directly  to  the  anchorage.  This  disadvantage  has  resulted 
ill  this  form  hecomiMg  nearly  obsolete. 

Any  brake  of  the  true  double-acting  tvpe  n-ill  work  equally  utM 
acting  forward  or  backward.  The  differential  brake.  Fig.  465, 
shows  this  clearly.  The  external  band  is  hung  from  the  main  frame 
by  means  of  a  stout  link  which  is  free  to  turn.  The  band  itself 
is  of  ver>'  thin  sheet  steel,  lined  with  some  form  of  non-biimable  belt- 
ing. The  ends  carry  drop  forgings,  to  which  the  operating  levers  are 
attacherl .  These  are  so  f*ha[)«*d  that  the  pull  is  evenl,\'  divided  between 
the  two  sides  of  the  band.  Thb  will  be  made  apparent  by  conadering 
that  a  pull  on  the  lever  //  will 
result  in  two  motions,  neither 
one  complete,  since  each  depends 
upon  the  other.  First,  there  will 
(^     ))         |l|  be  a  motion  of  the  upper  band 

end  B  about  the  extremity  of  the 
lower  one  as  a  pivot,  followed  by 


GASOUNE  AUTOMOBILES 


607 


of  side-by-side  internal  brakes  here  must  be  attributed  to  superiority 
rather  than  to  a  desire  to  save  in  money  or  in  parts. 

A  considerable  number  of  foreign  cars,  which  are  used  in  moun- 
tainous countries,  show  a  method  of  cooling  the  brake  drums  by  means 
of  external  cooling  flanges.  In  some  makes,  even  a  water  drip  is 
provided  for  extremely  hilly  country. 

More  modem  practice  shows  no  tendency  to  place  all  of  the  eggs 
in  one  basket,  both  forms  of  brake  being  employed  together  apd  upon 
the  same  car,  usually  also  upon  the  same  brake  drum,  one  set  working 


Flc.  we.     BcDi  Ci 


Bnkn  lor  Chun-Driven  Ch 


upon  the  exterior,  while  the  other  works  upon  the  inside.  In  Fig.  468, 
which  shows  the  rear-axle  brakes  of  the  larger  cars  made  by  the 
Peerless  Motor  Car  Company,  this  mechanism  is  plainly  illustrated, 
both  the  brakes  being  shown,  although  the  drum  upon  which  they 
work  has  been  removed.  The  parts  are  all  named  so  as  to  be  self- 
explanatory.  In  this  construction,  the  inner,  or  expanding,  band  is 
operated  by  a  cam.  In  the  brake  sets  put  out  by  the  Timken  Roller 
Bearing  Company,  of  Detroit,  Michigan,  in  connection  with  their  bear- 
ings and  axles,  the  toggle  action  is  used,  Fig.  469.  The  constructional 
drawings,  Figs.  470  and  471,  showing  the  brakes  used  on  the  Reo 
car,  manufactured  by  the  Reo  Motor  Car  Company,  of  Lansing, 


!    I 


cr 


GASOLINE  AUTOMOBILES 


In  general,  however,  when  both  brakes  are  placed  on  the  rear 
wheels,  one  external  and  of  the  contracting-band  type,  and  the  other 
internal  and  of  the  ejqjanding-shoe 
form,  modem  practice  calls  for  a 
cam  to  operate  the  latter,  oper- 
ating directly  upon  the  ends  of 
the  two  halves  of  the  shoe,  while 
)evers  operate  the  band  so  as  to 
get  a  double  contracting  motion. 

Some  modern  brakes  may  be 
seen  in  Figs.  472,  473,  and  474. 
The  first  shows  a  system  such  as 
just  described;  the  second  shows 
a  stiff  metal  shoe  in  both  types; 
and  the  last  a  pair  of  shoes  set 
side  by  side.  In  addition,  the  last- 
named  includes  a  new  thought  in        P'v-  IW.    Timken  Daub1«  Renr-Aile  Bnke 


Fia.  4T0.     BMtion 


that  the  brake  shoes  are  floated  on  their  supporting  pins,  as  shon-n. 
This  makes  the  bearing  of  the  shoes  certain  when  expanded  against 
every  portion  of  the  drum,  as  the  shoes  can  "float "  until  they  fit  exacdy. 


610 


G.VSOLIXE  AUTOMOBILES 


Double  Brake  Drum  for  Safety.  A  very  important  feature  b 
pointed  out  in  Fig.  472,  namely,  that  of  safety.  Where  hotli  brake* 
work  on  a  common  drum,  one  insirle  and  the  other  outside,  the  con- 
tinuous use  of  the  service  brake  (whether  internal  or  external)  heats 
lip  the  drum  to  such  an  extent  that  when  an  emergency  arises  calling 
for  the  application  of  the  other  brake  it  will  not  grip  on  the  hot 
drum,  being  thoroughly  heated  itself.  The  double  drum  allows  air 
circulation  and  constant  cooling. 

Methods  of  Brake  Operation.  While  it  is  generally  thought  that 
round  iron  rods  are  the  nni\crsal  means  of  brake  operation,  such  is  not 
the  case.  Many  brakes  on  excellent  cam  are  worked,  as  the  illus- 
trations show,  by  means  of  cables.    This  idea  is  e\'en  carrieii  so  far 


fiE^  i> 


GASOLINE  AUTOMOBILES 


I>I2 


lASOLINE   AUTOMOBILES 


wiseofr  their  n'spoctivc  brake  drums,  the  cable,  being  more  flexible, 
gives  less  flanger  nf  tiiis. 

Tliis  nietlKwl  of  operation  seems  to  be  gaining  favor  because  of 
its  siitiplicity.  wliieli  eliminates  parts  that  add  weight  and  gives 
immediate  results  when  the  parts  are  properly  adjusted.  The  recent 
Xew  York  show  rexcjiled  a  surprising  number  of  small  and  medium 
iiWiC  cars  with  eiihle-ojienited  brakes.  An  inspection  of  these  cars 
.showed  a  tiiceliaiiiriil  <  leanlJness  which  was  lacking  in  many  others  of 
the  same  class  on  whieh  an  attempt  was  made  to  reduce  braking  rods 


GASOLINE  AUTOMOBILES  613 

important  point,  and  one  that  should  be  looked  after  in  the  purchase 
of  a  new  car. 

Brake  Adjustments.  In  recent  years  much  of  the  brake  improve- 
ment has  been  that  of  making  adjustments  easier  and  of  making  the 
adjusting  parts  more  accessible.  This  can  be  noted  in  such  a  case  as 
the  Locomobile,  Fig.  472,  where  the  special  adjusting  handle  on  the 
brake  is  carried  to  such  a  height  as  to  make  the  turning  of  it  an  easy 
matter.  Similarly,  on  the  Pierce,  Fig.  473,  it  will  be  noted  that 
there  is  provision  for  increasing  or  decreasing  the  closeness  of  the 
shoes  to  the  drum,  which  is  easily  accessible. 

Brake  Lubrication.  As  for  the  actual  brake  surfaces,  there  is  no 
such  thing  as  lubrication.  The  surfaces  should  be  kept  as  dry  and 
clean  as  possible.  If  grease  or  oil  gets  out  from  the  axle  or  other 
lubricated  parts  onto  them,  there  is  sure  to  be  trouble.  The  operating 
rods  and  levers,  however,  should  have  fairly  careful  lubrication,  for 
which  purpose  the  best  makers  provide  grease  or  oil  cups  at  all  vital 
points.  If  these  be  neglected,  a  connection  may  stick,  so  that  when 
an  emergency  arises  the  brake  will  not  act  properly  and  an  accident 
may  result. 

Recent  Developments.  In  the  last  few  years,  the  only  new 
ideas  advanced  in  the  way  of  brakes  concern  front-wheel  braking 
and  electric  brakes.  The  former  were  used  quite  extensively  abroad 
in  1913,  but  in  1914  they  seemed  to  drop  back;  this,  too,  despite  the 
fact  that  the  Grand  Prix  race  of  the  latter  year  showed  in  a  marked 
manner  the  need  for  and  special  application  of  front-wheel  brakes  to 
racing  and  high-speed  cars. 

Electric  Brakes.  A  very  eflBcient  and  compact  brake,  appli- 
cable with  a  small  amount  of  work  to  any  chassis  having  a  storage 
battery,  is  the  Hartford,  shown  in  Fig.  476,  while  Fig.  477  shows  the 
operating  lever  as  it  is  placed  beneath  the  steering  wheel,  and  Fig.  478 
shows  the  wiring  system.  This  brake  consists,  in  substance,  of  a 
small  reversible  electric  motor,  to  which  a  100  to  1  worm  reduction  is 
attached.  Attached  to  the  drum  is  a  cable,  which  is  fastened  to  the 
usual  brake  equalizer.  Turning  the  current  into  the  motor  from 
the  storage  battery  rotates  the  drum,  winds  up  the  cable,  and  applies 
the  brake.  The  complete  outfit  weighs  but  35  pounds.  The  motor  has 
a  slipping  clutch  set  to  operate  at  1000  pounds  pull,  at  which  it  draws 
40  amperes  of  current  from  the  battery  for  two-fifths  of  a  seconc* 


r.ASOUNE  AUTOMOBILES 


In  use.  it  replaces  the  emer- 
gency hand-operating  lever, 
and  is  said  to  be  able  to  putl 
a  heavy  car  going  50  miles  an 
liour  down  to  less  than  15  in 
a  distance  of  less  than  35 
feet.  The  pull  is  so  great 
that  the  brake  drums  are 
oiled  to  prevent  heating  and 
possible  seizing. 

Hydraulic  Brakes.  On 
the  newer  Knox  tractors,  a 
brake  of  very  large  size  is 
made  even  more  powerful  by 
hjdraulic  operation.  This 
brake  is  shown  in  Fig.  479. 
At  the  left  will  be  seen  the 
il  brake  lever  attached  to 
a  small  piston  in  a  chamber 
full  of  liquid.     This  chamber 


GASOUNE  AUTOMOBILES 


615 


interaal-expanding  type,  are  exceptional  in  size  and  work  against 
steel  drums  attached  directly  to  the  wheel  spokes. 

When  the  lever  is  drawn  back  in  the  usual  manner,  liquid  is 
forced  upward  through  the  top  passage  to  and  through  the  pipes 
into  the  other  cylinder,  forcing  the  plunger  to  move,  and,  through  the 
movement  of  the  plunger,  the  brakes  are  applied.  The  return  of  the 
fluid  is  not  shown,  but  it  is  assumed  that  this  is  through  a  simple  pipe 
connection  from  the  plunger  cylinder  to  the  hand-operated  piston  with 
a  check  valve.  Should  the  initial  movement  of  the  lever  fail  to  apply 
the  brakes  sufficiently,  the  driver  can  let  the  lever  come  forward  and 
then  pull  it  back  again ;  in  so  doing  he  will  take  into  his  lever  cylinder 


more  hquld  from  below  without  releasing  the  brakes.  Then,  when 
this  extra  quantity  is  forced  through,  the  plunger  is  moved  even 
farther  forward,  and  the  brakes  applied  more  forcibly.  The  brakes 
are  20  inches  in  diameter  by  GJ  inches  wide. 

Vacuum  Brakes.  The  latest  development  in  the  line  of  braking 
systems  is  the  Prest-O-Lite  vacuum  brake.  This  brake  consists  of  a 
controlling  valve,  a  vacuum  chamber,  piping  from  the  inlet  manifold 
to  the  valve  and  thence  to  vacuum  chamber,and  a  foot  button  or  finger 
lever  on  the  steering  post  to  operate  the  valve  and  thus  put  the 
system  into  use.  The  rod  in  the  vacuum  chamber  is  connected  up 
to  the  service  brakes,  the  system  thus  taking  the  place  of  the  usual 
pedal  and  foot  operation.     The  chassis  sketch.  Fig.  480,  shows  this 


wui 


ClASOLINE  AUTOMOBILES 


ill  plan,  .t  Ix-ing  the  <-(iiitn)tlinK  valve,  BB  the  tubing  from  the  inlet 
iiiaiiifoM  to  the  i'iiiitn>llitj};  valve  and  from  it  to  the  vacuum  chamber 
('.  Tlic  niii  /'  fn>m  the  cliamber  will  be  seen  connected  to  the 
s<Tvi(v-t)rjikc  hmIs  uml  li'vcrs, 

III  Fif:.  tso  the  nictlnMl  of  operating  the  system  is  not  shown,  but 
in  Fij,'.  -IS!  tlii'  fnot  Icvor  can  be  seen  with  its  connections.  When 
this  is  prt'sscil,  the  (iintruilcr  valve  isopene<]  and  the  engine,  as  it  runs. 
draws  jiir  out  of  the  chainber  ('  in  back  of  the  plunger,  gradually 
(Tcalinn  a  viiciiiiiii.  so  that  the  plunger  is  forced  to  move  forward  to 
ciiinpcnsatc  for  this.  As  the  plunger  carries  a  tail  rod  projecting 
tliroufjli  tlic  cml  of  tlio  cylinder,  and  as  this  rod  is  connected  up  to  the 
lii'iikiii^:  systi'in.  but  with  a  big  leverage,  the  movement  of  the  plunger 


GASOLINE  AUTOMOBILES 


617 


possibilities  of  the  new  fonn  make  it  more  desirable  as  a  service  or 
running  brake. 

\Vhatever  advantages  may  develop  in  the  use  of  these  special 
tj^ies,  it  is  certain  that  the  next  few  years  will  see  considerable 
improvement  in  braking,  so  that  a  greater  force  may  be  applied  more 
quickly,  and  thus  act  to  prevent  a  large  part  of  the  accidents  for 
which  automobile  owners  and  drivers  are  now  unjustly  blamed. 
BRAKE  TROUBLES  AND  REPAIRS 

Draggii^  Brakes.    Probably  the  fiist  trouble  in  the  way  of 
brakes  is  that  of  dragging,  that  is,  braking  surface  constantly  in 


Fit-  481.     Foot 


contact  «ith  the  brake  drum.  This  should  not  be  the  case,  as  springs 
are  usually  provided  to  hold  the  brake  bands  off  the  drums.  Look  for 
these  springs  and  see  if  they  are  in  good  condition.  One  or  both  of 
the  brake  bands  may  be  bent  so  that  the  band  touches  the  drum  at  a 
single  point. 

Another  kind  of  dragging  is  that  in  which  the  brakes  are  adjusted 
too  tightly — so  tightly,  in  fa<'t.  that  they  are  working  all  the  time. 
In  operating  the  car,  there  will  be  a  noticeable  lack  of  power  and 
speed,  while  the  rear  axle  will  heat  constantly.  This  can  be  detected 
by  raising^  either  rear  wheel  or  both  by  means  of  a  jack,  a  quick 


C18 


GASOLINE  AUTOMOBILKS 


lifting  arranRciiieiit,  ur  a  cranp,  and  then  spinning  the  wheels.  11 
the  brakes  are  drafigiiif;.  they  will  nut  turn  freely. 

All  that  is  needed  to  remedy  this  trouble  is  a  better  adjustment- 
For  the  new  man,  however,  it  is  a  nice  little  trick  to  adjust  a  piu'roT 
brakes  so  that  they  will  take  hold  the  instant  the  foot  touches  the 
pedal,  that  they  will  apply  exactly  the  same  pressure  on  th«  turn 
wheels,  and  ,\-et  will  not  run  so  loose  as  to  rattle  nor  so  tight  as  to  drag. 

Dummy  Brake  Drum  Useful.  Wliere  a  great  deal  of  brnkr 
work  is  to  be  done,  particularly  in  a  shop  where  the  greater  [wirt  of 
the  cars  are  of  one  miike,  and  the  brakes  all  of  one  she,  a  great  dwl 
of  time  and  trouble  can  be  saved  by  havinK  a  set  of  test  drums.    An 


ordinary  brake  dnii 
may  be  observed  i: 


I  with  a  section  cut  out  so  that  the  action  inside 
all  that  is  necessary,  except  that  it  sliould  be 
As  shown  in  Fig.  4S2,  it  is  well  to  fit  a  pair  (if 
handles  to  the  brake  dniin 
to  Bit.sist  in  turning  the 
drum  when  the  adjustment 
is  being  maile.  The  reBl 
saving  consists  of  the  work 
which  is  saved   in  putting 


GASOLINE  AUTOMOBILES 


619 


what  causes  the  chattering.     If  the  lining  is  cut  away  for  about  30 

degrees  on  either  side  of  a  line  drawn  from  cam  to  pivot  pin,  as  shown 

in  Fig.  483,  it  is  said  that  this  chattering  will  stop  immediately. 

If  further  trouble  of  the 

same  kind  results,  bevel  off  '  — 

the  outside  ends  of  the  lining 

at  the  two  30-degree  points. 

A  number  of  sugges- 
tions in  the  way  of  possible 
brake  troubles,  particularly 
on  the  side-by-side  form  of 
internal-expanding  brakes, 
are  indicated  in  Fig.  484. 
This  shows  a  semi-floating 
form  of  rear  axle  with  the 
two  sets  of  brakes  and  oper- 
ating shaft  and  levers.  A 
number  of  suggestions  are  offere<l  for  this  form,  the  most  important 
of  which  is:     "Renew  worn  brake  lining  and  broken  or  loose  rivets." 

When  a  brake  lining  is  worn,  the  proceeding  is  much  the  same 
as  with  a  clutch  leather,  with  the  exception  that  whereas  the  latter 

dfiBnOrefiDajja 
^-al^opBrnnnfl levers  ^  c=  TQawwMim  bro)«linirjg 


IjTD^  ^  i^ilaoe  wJc  COM 
Fig.  484.     Biake  Tioubln  Illuitratvd 

must  have  a  curved  shape,  the  former  can  be  perfectly  straight  and 
flat.  This  simplifies  the  cutting;  but  most  brake  linings  are  made  of 
special  heatproof  asbestos  composition  which  is  made  in  standard 
widths  to  fit  all  brakes,  so  the  cutting  of  leather  brake  bands  is  not 
often  necessary. 


02(1 


GASOLINE  AUTOMOBILES 


Eliminating  Noises.  Many  times  the  brake  rods  and  levers 
wear  just  tnoiifjli  to  rattle  and  make  a  noise  when  running  over 
rnugli  rnads  or  cobblestone  pavements,  but  hardlj'  enougb  to  war- 
rant replaciTip  tlieni.  The  replacement  depends  on  the  accuracy 
with  which  they  work,  the  age  and  value  of  the  car,  and  the  attitude 
of  the  owner.  In  a  case  where  the  owner  does  not  desire  to  replace 
rattling  rods,  the  noise  can  be  prevented  by  means  of  springs,  winding 
with  tape,  string,  etc. 

If  tlif  mil  crusscs  a  frame  cross-member  or  is  near  any  other 
nu'lal  jjurt,  and  ils  lcnf;th  or  looseness  at  the  ends  is  such  that  it  can 
be  shaken  into  contact  there,  a  rattle 
wiU  result  at  that  point.     This  can 
(( '^')~^""~~-^^^  ^  remedied  or  rather  deadened  by 

wTapping  one  part  or  the  other.  For 
this  pur[X)se,  string  or  twine  can  be 
used  as  on  a  baseball  bat  or  tennis 
racket  liandle,  winding  it  together 
closely  so  as  to  make  a  continuous 
cohering.  Tire  or  similar  tape  may 
I  be  utilized.     When  this  is  dont'. 


GASOUNE  AUTOMOBILES 


621 


difficulty  of  doing  it  by  hand,  makes  the  stretching  device  shown  in 
Fig.  485  particularly  valuable  when  much  brake  relining  is  to  be  done. 
This  is  a  simple  pulling  clamp,  which  is  attached  to  one  end  of  the 
lining  after  the  first  end  has  been  riveted  in  place.  Then  it  is 
attached  to  the  end  of  the  shoe,  and  the  nut  tightened  so  as  to  stretch 
it.  When  it  has  been  stretched  sufficiently,  the  other  rivets  can  be 
put  in,  or  the  shoe  and  band  with  the  stretches  in  place  can  be  laid 
aside  for  a  while  to  stretch  it  fully  before  fastening.  Obviously,  this 
is  applicable  only  to  the  internal- 
expanding  form,  but  the  hook 
and  clamp  can  be  used  on  any 
size  or  type  of  expanding  brake 
Truing  Brake  Drums  When 
both  inside  and  outside  surfaces 
of  the  brake  drum  are  used  it  is 
highly  important  that  both  be 
true.  Since  they  do  not  stay  that 
way  long,  the  repair  shop  should 
be  equipped  to  true  them  up 
quickly,  Atruingdcvicelsshonn 
in  Fig.  486,  with  the  wheel  and 
brake  drum  in  place  on  it  One 
feature  of  the  device  is  that  brake 
drums  need  not  be  removed  from 
the  wheel.  The  device  consists 
of  a  metal  base  having  a  strong 
and  stiff  wooden  pier  with  a  hori 
zontal  ann  the  exact  size  of  the 
axle  end  mounted  on  it.  The 
wheels  are  placed  on  the  arm  and 
rest  on  it  the  same  as  on  the  axle  when  on  the  car.  The  tool  is 
double,  with  two  ends,  one  of  which  cuts  the  inside  surface  of  the 
drum,  while  the  other  cuts  the  outer  surface.  At  the  center  this  tool 
is  attached  to  a  heavy  casting,  bored  out  to  slide  over  the  shaft  and 
with  a  key  fitted  into  a  keyway  in  the  shaft  to  prevent  the  tool  from 
rotating.  The  end  of  the  arm  is  threaded,  and  a  large  nut  with  two 
long  arms  is  screwed  up  against  the  tool  at  the  start,  and  then  it  is 
used  to  feed  the  latter  across  the  work. 


Jig.  486,     AppBTBtm  lor  Tr — „  __ 

Outside  of  Bnke  Drum  in  Pliwe  m 

Cmnay  nfUiMtr  World" 


F^^     1 


GL>2 


GA!St)LINE  AUTOMOBILES 


Tills  issiilijcit  tna  iHimbcr  of  modifications  to  fit  it  to  the  various 
sizes  iiiiil  siiiiiiL's  ijf  brakf  drum.  Another  method  is  to  use  the  lathe, 
proviih'il  tlip  shop  is  I'quippefi  with  a  lathe  large  enough.  By  making 
a  niandroi  the  same  as  the  axle  spindle  and  having  a  pair  of  dummy 
bearings  to  pliti'e  on  it,  the  brake  drum  can  be  slipped  on  to  the 
mandrel,  ami  the  wlmlf  pnt  right  into  the  lathe.  The  surface,  either 
internal  or  exterrLal  or  both,  can  then  be  trued  Up  exactly  as  if  the 
drum  were  on  the  axle. 

WHEELS 

Broadly  speaking,  there  are  but  two  kinds  of  wheels  according 
to  the  service  each  is  to  Render,  pleasure-car  wheels  and  commercial- 
car  wheels.  The  former  may  he  further  subdivided  into  wood,  wire, 
and  spring  wheels;  while  the  latter  may  be  divided  into  wood,  steel, 
and  spring  wheels.  Smne  of  the  commercial  vehicle  wheels  are 
further  divisible,  as  steel  wheels  into  sheet  steel  and  cast  steel; 
wiioci  into  .siHiked  and  solid;  and  spring  wheels  into  various  tj-pes. 

Wheel  Sizes.  Wheels  are  used  on  automobiles,  in  combination 
the  tins.  In  ali'nri!  a  resilient  and  yielding  contact  with  the 


GASOLINE  AUTOMOBILES 


by  1^  inches  deep.  In  both  cases,  A  shows  the  28-incb  wheel  and  B 
shows  the  40-inch  wheel.  Both  instances,  too,  have  been  selected  at 
random,  and  not  so  chosen  as  to  favor  either  wheel.  It  would  have 
been  possible  to  so  select  the  sizes  of  both  obstruction  and  depression 
as  to  make  out  a  stronger  case. 

The  height  of  the  brick  being  2  inches  the  wheel  must  rise  that 
distance,  whatever  its  diameter,  but  in  the  case  of  the  2S>incb  wheel, 
this  rise  of  2  inches  is  largely  relative  to  the  wheel  diameter  being 
one-fourteenth,  or  7  per  cent.  In  the  case  of  the  larger  wheel  of 
40-inch  diameter,  the  rise  is  again  2  inches,  but  it  is  now  one- 
twentieth  of  the  wheel  diameter,  or  5  per  cent.    In  the  case  of  the 


Fia.  487.     Diacrun  Showini  AdnnUfe  ot  Luge  Whnli  io  Pusing 


smaller  wheel,  the  rise  is  distributed  over  a  length  of  about  18.43 
inches  from  the  moment  when  the  fom-ard  edge  strikes  the 
obstacle  to  the  moment  when  the  last  part  of  the  tire  leaves  the 
last  edge  of  the  brick.  If  this  rise  were  evenly  distributed  over 
this  distance,  rising  as  an  arc  of  a  circle,  its  radius  would  be  slightly 
over  22  inches. 

Considering  the  40-inch  wheel  under  the  same  circumstances,  it 
performs  the  act  of  rising  and  falling  2  inches  in  the  longer  dbtance 
of  about  21.5  inches,  the  radius  of  this  rise  being  38.75  inches.  It  is  - 
obvious  that  the  latter  is  a  much  easier  rise  than  the  former,  the 
lift  being  distributed  over  a  length  16  per  cent  greater.  Similarly, 
with  the  descent  from  the  high  point  to  the  surface  of  the  road  agam, 


IWI  (lASOLINE  AUTOMOBILES 

this  more  gradual  rise  and  fall  convert  the  surmounting  of  the 
ribstiitlf  frtim  a  sharp  upward  bump  and  downward  jounce  into  an 
easy  iimi  not  unjiii-asant  swinging  up  and  down. 

A  drill)  ''If'"'  *i  h()l(\  as  illustrated  by  Fig.  488,  shows  the  bene- 
ficial etVet't  of  the  lar^e  wheel  better,  perhaps,  than  does  the  rolling 
over  a  rise.  A  rut  in  the  road  8  inches  across,  into  which  the  two 
wheels  <irop  in  passing,  is  shown.  At  A ,  the  28-inch  wheel  is  seen  to 
drop  the  considerable  amount  of  yb  inch,  while  at  B  the  40-inch 
wliecl  drops  but  ^  inch  into  the  same  hole.  Evidently  the  larger 
wheel  has  an  advantage  in  so  far  as  passing  over  obstacles  or  holes 
is  concerned. 

A^aiii,  on  account  of  its  larger  radius,  the  arc  of  the  larger 
wheel  is  flatter  and  has  more  length  nf  tread  in  contact  with  the 


GASOLINE  AUTOMOBILES 


625 


Fif.  489.    Con 


the  felloe  on  which  is  the  rim  B,  and  R  is  the  spoke  which,  at  the  hub 
end,  tapers  down  to  the  wedge-shaped  portion  P.  This  matches  up 
to  the  wedge-shaped  ends  of  the  other  spokes,  so  that  when  the 
wheel  is  assembled  they  form  a  continuous  rim  around  the  central 
or  hub  hole. 

The  spokes  are  held  at 
their  inner  ends  by  metal 
plates  and  by  through  bolts, 
which  are  set  at  the  joints 
between  the  spokes  so  as  to 
pass  equally  through  each 
spoke,  as  shown  at  D.  Not 
only  do  these  bolts  hold  the 
spokes  firmly  to  the  wheel, 
but  they  have  an  expand- 
ing, or  wedging,  action 
tending  to  make  the  center  of 
the  wheel  very  rigid. 

The  outer  end  of  the  spoke  has  a  shoulder  E  and  a  round  part  C,  ■ 
which  fits  into  a  hole  bored  through  the  felloe.  To  prevent  the 
felloe  coming  off  after  the  spoke  is  in  place,  the  spoke  is  expanded 
by  means  of  a  small  wedge  driven  into  it  from  the  outside,  as  shown 
at  F.  In  this  way,  the  wheel  is 
constructed  from  a  series  of  com- 
ponents into  a  strong  rigid  unit. 

Such  wheels  wear  in  two 
places,  at  the  inner  and  at  the 
outer  ends  of  the  -spokes.  The 
remedy  in  the  latter  case  is  to 
withdraw  the  small  wedge  and 
insert  a  larger  one  in  its  place. 
At  the  hub  end,  when  wear  occurs, 
this,  too,  must  be  taken  up  by 
means  of  wedges.  Fig.  490  shows 
a  method  of  doing  this  when  the  hub  has  no  bolts  at  the 
joints.  A  false  steel  hub  A  is  driven  into  the  hub  hole,  after 
which  wedges  of  steel  are  driven  in  between  the  wedge-shaped  ends 
of  the  spokes.    For  slight  cases  of  wear  and  squeaks,  the  wheel  may 


GASOLINE  AUTOMOBILK?! 

be  soaked  in  iviiter,  which  will  cause  it  to  swell,  tiikJlig  Up  till  of 
the  space. 

There  are  various  nnwlificationa  of  this,  nearly  all  of  them 
changing  the  hub  end  of  the  spoke.  In  tlie  Schwartz  wheel,  a  patented 
form,  each  spoke  is  made  with  a  tongue  on  one  side  of  the  wedge^ 
shaped  part  and  a  groove  on  the  other.  In  assembling  the  wheel, 
the  tongue  of  each  spoke  fits  into  the  groove  of  the  spoke  next  to 
it,  thus  rendering  the  whole  hub  end  of  the  wheel,  when  assembled, 
a,  stronger  unit,  being  .-itronger  in  two  directions,  one  of  them  of 
more  than  ordinary  value.  In  driving  the  tongue  into  the  groAve. 
the  wheel  is'reuilered  strong  in  a  radial  direction,  but.  when  the  wh«l 


GASOLINE  AUTOMOBILES 


627 


these  conical  shapes  is  stronger  to  resist  stresses  from  the  side  on 
which  the  point  is  located  than  would  be  the  same  number  of  spokes 
set  flat.  Hence,  the  staggered-spoke  wheel  has  the  ad\~antage  over 
the  ordinar>'  tj'pe  in  that  it  has  greater  strength  from  both  sides. 
In  the  figure,  A  is  the  iron  hub,  B  the  felloe,  Ci  the  right-hand  and 
Ct  the  left-hand  spoke,  and  D  the  steel  rim  for  the  tire.  This  is  a 
12-3poke  wheel,  6  of  the  right>hand  spokes  Ct  and  6  of  the  left-hand 
spokes  Ct.  The  section  shows  how  these  pass  alternately  to  the  one 
»de  or  to  the  other,  forming  the  strong  cone  shape. 


Another  method  of  handling  this  problem  in  a  somewhat  similar 
manner  is  the  use  of  double  sets  of  spokes,  the  spokes,  however,  being 
in  two  different  planes  separated  a  considerable  distance  at  the  hub. 
Of  a  necessity  using  the  same  felloe,  the  outer  ends  must  be  m  the 
same  plane.  Fig.  492  shows  a  drawing  representing  a  section  through 
the  center  line  of  the  wheel,  while  Fig.  493  shows  a  photographic 
reproduction  of  it. 

In  Figs'.  492  and  493,  A  represents  the  steel  rim  on  the  felloe 
F,  the  latter  being  of  metal  in  this  case,  as  is  also  the  wheel  so  it 


almost  every  case,  break  practica 
sitating  a  new  wheel  instead  of  ne^ 
Wire  Wheels.  Many  of  the 
were  inherited  from  its  predecessoi 
-  be  mentioned  the  wire  wheel.    Pi 


Early  Bicycle  Modek.  Fig.  4' 
wheel  for  automobiles,  its  construci 
ancestry.  The  spokes  were  set  into 
and  into  the  steel  rim  by  means  ol 
each  end  of  the  spoke  resting  on  tl 
sleeves  were  screwed  in  and  out  to 
This  tension  was  usually  considen 


GASOLINE  AUTOMOBILES 


Following  the  failure  of  wire  wheeb,  there  was  a  rapid  change 
to  wood  wheels,  which  were  almost  universal  for  several  years. 
Soon  after  this  change  was  made,  there  was  an  increase  in  the  size 
and  power  of  automobiles,  which,  in  turn,  was  followed  by  a  demand 
for  lessened  weights.  In  the  meantime,  makers  of  wire  wheels, 
knowing  their  faults,  began  to  re-design  in  order  to  eliminate  them. 
Their  success  is  best  evidenced  abroad,  where  about  one-half  of  the 
French  and  more  than  two- 
thirds  of  the  English  cars, 
in  addition  to  over  seven- 
eights  of  the  racing  cars 
in  both  countries,  are  now 
equipped  with  wire  wheels. 

New  Successful 
Designs.  This  result  has 
been  brought  about  by  a 
realization  of  the  previous  ! 
defects  and  their  elimina- 
tion. Thus,  no  more  cast 
hubs  are  used,  drawn  or 
pressed  steel  of  the  highest 
quality  and  greatest 
strength  being  used  instead. 
The  spokes  have  been  car- 
ried out  farther  apart  at 
the  hub,  obtaining  a  higher 
cone  and  thus  a  stronger 
one.  Spoke  materials  are 
better  and  stronger,  besides  being  used  in  greater  quantities,  that 
is,  larger  spokes  and  larger  numbers  of  spokes  per  wheel,  in  some 
cases  a  triple  row  of  spokes  being  used  in  addition  to  the  ordinary 
two  rows.  This  additional  row  acts  as  a  strengthener  and  stlffener 
much  like  the  diagonal  stays  on  a  bridge.  Fig.  495  shows  a  set  of 
double-spoke  wire,  triple-spoke  wire,  and  interchangeable  wood 
wheels  side  by  side  for  comparison,  while  in  Fig,  496  is  presented 
a  recent  triple-spoke  front  wheel  in  detail. 

In  the  former  figure,  the  relative  depths  of  the  various  cones 
and  their  corresponding  strengths  are  made  evident,  being  side  by 


GASOLINE  AUTOMOBILES 


side.  In  this  comparison,  it  will  be  noted  that  the  new  triple-spoke 
wheel  has  a  much  lonser  outer  cone  than  the  (ionlilospokt  wbocl, 
while,  on  the  other  haiul,  the  inner  cone  has  been  flattened.  The 
triple  spoke  has  ii  greater  depth,  coiisideriiin;  the  set  of  tiicrn  us  ttfi 


additional  cone,  than  ht 
In  exaniininj:  i 


the  inner  cone  in  the  doublc-aet  wliecU. 
the  older  donl)ie-siHikc  fonn  and  the  newer 
triple  tj'po.  it  will  he  noted,  also,  how  the 
wheel  it-self,  or  rather  the  tire  and  rim, 
have  been  brought  closer  in  to  the  point  of 
attachment,  thus  rendering  the,  whole  con- 
struction stronger  and  safer.  In  Fig,  495. 
it  will  be  seen  that  (he  center  line  o( 
hotli  tire  and  rim  passes  midway  lietween 
the  inner  anti  outer  ends  of  tlie  hub  on 
doubk-spoke  wheels,  while  on  the  triple 
form  it  is  e^'en  with  the  inside  end  of  the 
inner  hub,  being,  in  fact,  farther  in  than 
ia  the  case  with  the  wood  wheel,  One 
thing  will  lie  noted  in  all  these  spokes, 
regardless  of  number,  position,  or  inclios- 
rion.  and  thnt  la  that  their 


GASOLINE  AUTOMOBILES  631 

All  these  arguments  in  favor  of  wire  have  been  built  up  one  by 
one,  for  much  prejudice  had  to  be  removed.  In  spite  of  this,  however, 
the  wheel  is  slowly  but  surely  building  up  a  reputation  and  a  long 
list  of  friends.  Since,  even  now,  England  and  the  Continent  continue 
to  set  the  fashion  in  automobiles,  it  is  not  too  much  to  expect  to 
see  wire-spoke  wheels  in  common  use  in  the  United  States  in  a  few 
years.  In  fact,  the  dozen  manufacturers 
offering  this  wheel  in  1914,  with  ten  more 
giving  it  as  an  option,  have  been  increased 
to  about  forty  who  are  fitting  it  regularly, 
with  perhaps  fifty  or  more  offering  it  as  an 
option  in  1915.  In  fact,  almost  any  car 
maker  in  the  country  will  fit  wire  wheels 
for  a  slight  additional  charge. 

For  1917  some  20  odd  makes 'of  "cars 
are  offered  with  wire  wheels  as  regular 
equipment,  and  about  25  more  offer  this 
as  an  option  without  extra  charge.  As 
there  are  about  190  cars  on  the  market, 
the  former  represents  10.5  per  cent,  and 
the  latter  13.2  per  cent  of  all  makes;  the 
two  together  total  23.7  per  cent,  or  less 
than  one-quarter.  However,  these  figures 
do  not  quite  indicate  the  relative  popu- 
larity of  wire  wheels. 

Wire  Wheels  Muck  Stronger.  The 
increase  in  the  use  of  wire  wheels  has 
been  brought  about  by  better  designs; 
greater  attention  to  the  details  of  manu- 
facture, assembly,  and  use;  but  primarily 
by  the  greater  strength  which  has  been 

built  into  the  wire  wheel.     One  way  in      ^^  ^pj    (;.„^  ouKirupie- 
which  this  has  been  done  is  by  rearrange-  ^'"'"  "'"  **""' 

ment  of  the  spokes  as,  for  instance,  the  triple-spoke  form  just 
described  and  shown  in  Fig.  469.  Another  and  later  form  is  the 
quadmple-spoke  wheel  as  seen  in  Fig.  497.  This  is  made  and  sold  by 
the  General  Rim  Company,  Cleveland,  Ohio,  find  is  called  the  G-R-C 
wheel.      As  the  sketdi  indicates,  It  has  all  the  features  of  demount- 


iibility,  etc.,  nt  other  wire  wheals,  the  notable  differences  being  the 
spoke  arrangement  to  gi\'e  strength  and  the  form  of  rim — a  patentfd 
form  to  be  described  in  detail  later. 

By  comparison  with  Fig.  496,  it  will  be  noted  that  a  double 
triangular  section  is  formed  in  the  G-R-C,  the  inner  spokes  forming  the 
inside  of  the  hub  and  the  outside  of  the  hub  forming  one  triangle, 
while  the  outer  spokes  from  each  form  the  other.  In  Fig.  49tt,  it 
will  be  noted  that  there  is  but  the  one  triangle  and  a  straight  row 
of  spokes. 

Sheet-Steel  Wheels.  The  sheet-steel  wheel  is  really  a  form  of 
wire-spoke  wheel,  with  an  infinite  numlier  of  spokes  joined  together. 
It  has  many  advantages,  some  of  whioli  might  be  mentioned  fUt 
follows;  strength,  lightness,  low  first  cost,  low  cost  of  maintenance, 
and  cleanliness.  To  take  them  up  in  order,  the  strength  of  two  sted 
plates  set  a  few  inches  apart  in  a  somewhat  triangular  form  with 
the  base  toward  the  Hub  and  well  attached  at  the  ceiittr  and  at  tile  rim 
of  the  wheel,  is  self-evident.  Aside  from  the  natural  strength  of  the 
steel  plate.-i^far  in  excess  of  the  wire  spokes— or  round  wood  spokes, 
there  is  the  strength  of  the  triangular  form.    A  .strong  connection  at 


GASOLINE  AUTOMOBILES 


633 


hub  construction  is  much  cheaper  than  the  ordinary  hub,  for  the 
reason  that  there  are  usually  two  parts  where  this  construction 
requires  but  one,  and  this  a  very  simple  one  needing  little  machining. 
Low  maintenance  cost  is  brought  about  by  the  rigidity  of  the  whole 
construction;  the  few  parts,  which  make  few  to  replace  or  even  to 
wear;  the  cheapness  of  these  parts,  when  replacement  is  necessary; 
and  the  well-known  strength  and  long  life  of  sheet-steel  plates. 

On  the  score  of  cleanliness,  it  may  be  said  that  this  is  one  of 
the  drawbacks  of  the  wire-spoke  wheel,  cleaning  between  and  around 


the  spokes  being  very  difficult,  if  not  actually  impossible.  The 
large  number  of  spokes  makes  the  hub  inside  of  the  spokes  impossible 
to  clean,  whereas,  with  the  sheet-steel  wheel,  the  cleaning  consists 
in  merely  turning  a  hose  on  the  sides  of  the  wheel,  the  cleaning  of 
the  hub  being  entirely  unnecessary. 

It  will  be  noted,  too,  in  this  illustration  that  the  wheel  has 
con^derable  spring,  or  should  have,  in  a  vertical  direction.  It  is 
claimed  for  this  tj-pe  of  wheel  that  this  springiness  is  an  added 
advantage  as  it  allows  the  use  of  solid  or  cushion  tires,  and  thus 


634  GASOLINE  AUTOMOBILES 

eliminates  the  troubleaome  pneumatic  tire  witli  its  puncture  and 
blowout  possiljitities.  For  coraraercial-car  use,  all  of  the  ad\antugi-s 
just  mentioned  are  of  ilmibte  worth,  for  which  reason  the  steel  wheel 
is  malting  great  strides  forward  on  commercial  cars,  Wierc  the 
springiness  of  the  wheels  is  not  so  desirable  as  strength,  the  sbect- 
steel  plates  ma.\-  \te  replaced  with  either  pressed-  or  cast-stcd  side 
members  on  which  htrcngtheiiiuiL!  rib^  are  furmerl.  The  aide»  of  the 
wheel  have  holes  ////  through  them  which  are  provided  for  venUIa- 
tion.  to  decrease  the  neight  of  the  side  sheets,  and  to  lessen  the  wind 
resistance  to  the  wheel  when  moving  rapidly.  In  some  steel  wheels 
these  holes  are  omitted;  in  others  a  larger  number  than  the  four 
shown  here  are  used.  Fig. 
499  gives  a  better  idea  of 
the  general  appearance  of  the 
wheel  ready  to  use,  being 
lettered  the  same  as  Fig.  498. 
The  sixikes  shown  in  Fig,  -199 
are  painted  on  the  smooth 
exterior  of  the  plates,  but  in 
other  wheels  these  spokes  are 


GASOLINE  AUTOMOBILES 


635 


end  and  attached  to  a  middle  flange  on  the  hub.  The  two  outer 
members  of  themselves  would  be  very  springy  and  consequently 
very  weak,  being  of  very  thin  metal.  The  diagonal  extra  sheet  stiffens 
the  whole  construction,  besides  adding  50  per  cent  to  its  side  strength. 
This  is  also  of  thin  metal,  so  the  whole  wheel  retains  some  springiness. 
Parker  Pressed-Steel  Wheels.  One  fault  with  all  the  steel  and 
sheet-steel  wheels  mentioned  was  that  they  did  not  resemble  other 
wheels,  consequently  the  people  did  not  want  them.  Moreover,  in 
many  cases,  their  construction  did  not  adapt  them  to  the 
use  of  regular  tires  but,  on  the  contrary,  called  for  special 
and  expensive  forms.  However,  none  of  these  drawbacks 
are  present  in  a  new  form  of  pressed-steel  wheel.  Fig.  502. 
Upon  close  inspection  it  will  be  seen  that  this  wheel  has 
no  felloe  in  the  ordinar;'  sense,  the  rim  of  the  wheel  form- 
ing the  only  felloe.  In  this  respect,  the  wheel  is  an 
outgrowth  of  the  former  Healy  demountable  rim,  the 


modem  form  being  a  combination  of  a  demountable  rim  with  steel 
spokes.  This  wheel  is  suitable  for  any  car,  the  hollow  steel  spokes  hav- 
ing great  sustainiiig  power.  It  is  interchangeable  with  all  ordinary 
wood  artillery  wheeb  of  the  same  size,  and  fit's  between  the  usual  hub 
flanges.  The  spoke  portion  is  made  as  a  pair  of  units,  each  forming 
half  of  all  the  spokes,  the  two  being  welded  together.  When  finished 
in  this  manner,  they  have  half  the  weight  and  more  than  twice  the 
strength  of  the  wood  wheel,  the  greatest  saving  being  at  the  rim, 
by  the  removal  of  from  60  to  100  pounds  of  metal  and  wood. 

This  wheel  takes  the  ordinary  demountable  rim  directly  upon 
the  ends  of  the  spokes,  the  one  shown  being  the  No.  1\  '«\w5&">a,  *\s*j- 


Dy  pressingout  two  or  more  sim[ 


Fi(.  S03.     General  Appraraniv  ii[  Pukcr  H 

below  the  price  ol  wood  wheels 
COMMERCEA 

Requisites.  On  commercial 
to  call  for  entirely  different  whf 
car  wheels  are  notliine  but  nlea 


GASOLINE  AUTOMOBILES  637 

will  make  for  low  first  cost  and  low  cost  of  maintenance.  A  fourth 
desirable  quality -might  be  added  to  these,  the  quality  of  being 
adaptable  or  adapted  to  the  tires  to  be  used. 

Wood  Wheels.  Taking  Fig.  503  as  an  ordinary  heavy  vehicle 
wheel,  let  us  see  in  what  ways  it  fulfills  or  falls  short  of  these  require- 
ments. The  spokes  are  large  in  both  directions  antt  widened  out  at 
the  felloe  to  give  greater  side 
strength.  The  felloe,  which 
cannot  be  seen,  may  be  judged 
as  to  size  from  the  width  and 
location  of  the  dual  tires, 
which  would  indicate  great 
width  and  considerable  thick- 
ness. This  style  of  tire  calls  for 
a  steel  band  shrunk  over  the 
felloe,  while  the  heads  of  the  i 
cross-bolts  show  how  the  tires 
were  put  on  and  held  on. 
AH  these  make  for  great 
strength  in  both  horizontal 
and  vertical  directions,  and 
all  parts  except  the  spokes 
are  simple  to  make,  and  even 
these  are  simple  for  the  wheel 
manufacturer  whose  shop  is 
rigged  to  make  them.  More- 
over, to  fill  the  last  require-  ''«-  =^'  i>°'''"=-t-  w™i  Truct  wh»i 
ment,  the  wheel  is  adaptable  to  this  tire  or  to  any  one  of  a  number  of 
motor-truck  tires  which  might  be  used. 

A  slight  variation  from  this  is  the  double-spoke  wheel,  in  which 
the  spokes,  in  addition  to  being  placed  in  double  rows,  are  set  so 
as  to  miss  each  other  across  the  wheel,  that  is,  each  spoke  of  one 
row  coming  between  two  of  the  other.  This  placing  allows  the  spokes 
to  be  made  larger  and  stronger  than  in  the  ordinary'  case,  while  the , 
double  rows  have  the  same  strengthening  effect  as  the  tapering  of 
spokes.  The  hub  portion  is  assembled  as  two  separate  wheels,  su 
that  the  work  of  assembling  as  well  as  of  making  the  parts  is  slightly 
more  than  with  the  ordinary  wheel.    This  is  more  than  compensated 


nng  with  a  con 


Fig.  E04.   -Whi. 

over  the  wood  shoulder  on  each 
much  like  the  ordinary  steel  tii 
Bolts  are  run  through  these  rinirs 


GASOLINE  AUTOMOBILES  639 

It  is  said  that  one  set  of  these  tires  was  used  for  nine  months, 
and  at  the  end  of  that  time  they  were  still  good  for  service.  The 
tires  reach  clear  to  the  hub,  thus  doing  away  with  spokes  and  enabling 
the  tires  to  be  slipped  over  the  hub  and  held  in  place  by  a  removable 
flange  bolted  through  the  wood  to  the  fixed  flange  on  the  opposite 
side  of  the  hub. 

Cast-Steel  Wheels.  The  heavier  the  service  the  more  unsuit- 
able do  wood  wheels  become,  that  is,  wood-spoke  wheels.  For  many 
five-ton  trucks,  practically  all  seven-  and  ten-ton  trucks,  and  nearly 
nil  tractors,  the  cast-steel  wheel  is  used,  either  spoked  or  solid,  the 
spokeil  form  being  given  the  preference.  Fig.  5()4  illustrates  a  spoked 
cast-steel  wheel,  fitted  with  a  solid  tire.  The  wheel  is  cast  with  ten 
heH\y  ribbed  spokes,  a  ribbed  felloe,  and  a  grooved-felloe  surface, 
into  which  the  tire  is  set. 

Miscellaneous  Wheel  Types.  Steel.  Steel  wheels  are  gaining 
for  heavy  truck  use,  and  a  number  of  the  better  steel-casting  firms 
are  now  getting  into  this  work,  with  the  result  that  better  steel 
wheels  are  becoming  available. 

Other  constructions,  such  as  steel  and  wood  combination  wheels 
with  removable  and  replaceable  spokes,  and  the  like,  are  rapidly 
going  out  of  existence.  Truck  work  is  unusually*  severe,  and  it  takes 
but  a  few  weeks  of  actual  use  to  show  up  any  of  the  so-called  freak 
wheels.  The  simplest  seems  to  be  the  best,  the  only  question  at 
present  being  whether  the  material  shall  be  wood  or  cast  steel. 
Pressed  steel  may  offer  some  opportunities  in  combination  with 
welding,  since  good  work  has  been  done  on  pleasure-car  wheels  of 
this  type. 

Spring  Wheels  wUh  Longitudinal  and  Tangential  Springs.  Spring 
wheels  for  both  pleasure  cars  and  trucks  have  not  proved  to  be  all 
that  was  claimed  for  them.  For  pleasure-i'ar  use  thej-  have  gone 
out  entirely;  for  truck  use  they  are  restricted  to  the  smaller  and 
lighter  sizes,  as  the  IJ-  and  2-ton  sizes  driven  at  higli  speeds  in  city 
work.  On  these  sizes,  one  or  two  well-designal  forms  are  giving 
good  service-  The  cherished  dream  of  putting  the  pneumatic  tire 
out  of  business  thniugH  the  medium  of  the  spring  wheel  is  still  a  dream. 
^  When  longitudinal  springs  are  used  to  do  away  with  the  alter- 
nations of  stresses  peculiar  to  the  radially  disposed  springs,  the 
appearance  of  the  wheel  is  much  altered,  as  Fig.  505  shows.    This 


Fie.  ^o.    Seaton  (; 

felloe,  while  those  attached  to  tl 


GASOLINE  AUTOMOBILES  &41 

oiisly  moved  forward.  Since,  however,  the  springs  have  a  certain 
amount  of  stiiTness  in  their  coils,  and  the  wheels  do  not  rise  and  fall 
relative  to  one  another,  except  in  so  far  as  the  twisting  action  is 
concerned,  it  follows  that  considerable  shock  must  be  transmitted  . 
to  the  axle  and  thus  to  the  body  and  its  occupants.  This  wheel, 
therefore,  while  possessing  strength  to  resist  side  stresses,  does  not 
give  the  smooth  riding  qualities  so  much  desired. 

A  wheel  very  similar  in  appearance  and  action  but  with  the 
wood  spokes  eliminated  has  been  used  very  extensively  in  the  last 
few  years  by  the  express  companies  and  other  big  users  of  motor 
trucks.  Starting  with  a  few  of  them  on  front  wheels,  they  have 
saved  tires  and  tire  money 
to  such  an  extent  that 
the  companies  have  added 
more  and  more.  Next  they 
were  tried  on  rear  wheels. 
Seeing  the  good  results 
obtained  by  the  big  com- 
panies with  these  wheels, 
many  smaller  firms  and 
tradesmen  with  only  one 
or  two  trucks  have  adopted 
them.  They  take  a  small  size 
solid  tire  in  place  of  a  very 
large  pneumatic  and  are  said 
to  cut  the  tire  cost  from  one- 
half  up  to  two-thirds  and  more.  While  used  mainly  for  vehicles  carry- 
ing a  1-ton  load,  they  have  been  tried  successfully  on  2-ton  vehicles. 

It  is  in  this  class  of  service — the  lighter  vehicles  for  smaller  firms 
— where  every  item  of  expense  must  be  watched  very  carefully  that 
the  resilient  wheel  should  show  the  best  results.  For  heavy  work, 
there  seems  little  future  for  it. 

A  form  of  wheel  which  comes  somewhere  between  the  two  just 
mentioned,  having  some  side  strength  and  easy-riding  qualities,  while 
at  the  same  time  participating  in  part  of  the  principles  of  both  those 
described,  is  that  shown  in  Fig.  506,  which  is  a  diagram  showing  the 
construction.  This  consists  of  spiral  springs  used  not  radially  nor 
loogitudinidly,  but  tangentially.     Moreover,  the  springs  are  not 


t  lit:  construction  is  si 
by  muaiis  of  a  water-tigli 
elements  and  thus  lengtlio 
is  lacking  in  all  other  whe 

Spring  IV keels  uitk  F 
into  a  semicircular  or  spii 
There  is  a  double  reason  f 
unless  it  be  side  strength. 
load, they  are  heavy,  they 
continued;  if  made  light,  t) 
long  drawn  out.  Morenvei 
of  a  single  one  puts  the  whe» 
l)ecomes  verj-  hea\y. 

While  a  number  of  flat-s 
lM>th  here  and  abroad,  theyh 
l)een  pointe<l  out.  A  French 
ugo  had  a  pair  of  sets,  each  r 
one  end  attached  to  the  hub  t 
on  the  two  sides  were  set  in 
lomling  would  produi.^'  an  c 
to  the  hub.  and  that  the  op 
produtt'  an  absorption,  one  si 
of  the  other.  In  practice,  ht 
gave  a  noisy,  harcl-ridint'  "4 


.-.*——.*-  -        ■  ■!  I  ■»^»^1^^W'— Bl^^l 


GASOLINE  AUTOMOBILES  643 

itages  of  wood  and,  in  addition,  will  so  save  the  solid  rubber  tires  that 
'mileages  twice  as  great  will  be  obtained.  In  this  way;  the  tire  cost 
will  be  cut  in  half,  which  will  be  sufficient  within  the  ten-year  life  of 
the  ordinary  commercial  car  to  warrant  the  purchase  of  the  more 
expensive  wheels. 

In  the  use  of  spring  wheels,  as  well  as  of  wire  wheels  for  pleasure 
cars,  the  tire  and  rim  situations  are  closely  jnter-woven.  No  special 
form  of  wheel  or  rim  can  be  successful  which  calls  for  a  special  tire  in 
addition,  because,  in  case  of  trouble  on  the  road,  in  a  small  town,  or 
an>'where  outside  of  the  big  cities  with  large  and  varied  sources  of 
supply,  the  users  would  not  be  able  to  replace  the  tire.  As  will  be 
pointed  out  later,  the  present  rim-and-felloe  situation,  which  might  be 
described  as  chiaotic,  must  necessarily  continue  until  the  tire  situation 
is  cleared  up.  That  done — and  it  is  now  in  a  fair  way  of  being  done 
soon — the  rim  situation  also  will  be  quickly  cleared  up,  and,  following, ' 
that  of  the  wheel  felloes.  The  natural  fitness  of  the  various  forms  and 
the  unfitness  of  others  to  meet  popular  demand  is  rapidly  clearing  the 
way  for  the  engineers  and  manufacturers  who  are  attempting  this 
standardization  work. 

WHEEL  TROUBLES  AND  REPAIRS 

The  removal  and  handling  of  wheels  present  probably  the 
biggest  problems  in  connection  with  them.  True,  broken  wheels 
give  the  repair  man  a  good  deal  to  think  about,  but  the  quick  accu- 
rate handling  of  jobs  in  which  a  broken  wheel  figures  depends  more 
upon  possessing  and  knowing  how  to  use  certain  equipment  than 
anything  else;  the  operations  are  so  simple  that  they  require  no 
particular  skill  or  knowledge. 

Wheel  Pullers.  In  handling  wheels  a  wheel  puller  of  some  form 
is  generally  a  necessity;  wheels  are  removed  so  seldom  that  they  are 
likely  to  stick,  and  they  get  so  much  water  and  road  dirt  that  there 
is  good  reason  for  expecting  them  to  stick  or  to  be  rusted  on.  This 
means  the  application  of  force  to  remove  the  wheel.  For  this  purpose, 
a  wheel  puller  is  needed,  and  a  number  of  these  have  been  illustrated 
and  described  previously,  as  gear  pullers,  steering-wheel  pullers, 
etc.  Any  one  of  these  devices  which  is  large  enough  to  grasp  the  spokes 
of  the  wheel  and  pull  the  latter  outward  and,  at  the  same  time,  press 
firmly  against  the  protruding  axle  shaft  V\\\  Ao  ^-^  ^«^  ^^. 


GASOLINE  AUTOMOBILES 


Sometimes,  liowever,  while  owning  a  puller,  a  wheel  breaks 
tliis  is  not  available,  or  the  repair  man  is 
the  tn)ui>le,  so  that  he  dws  not  bring  the 
puller  with  him.  In  sueh  vases, 
the  repair  man  must  improvise 
some  kind  of  apuller  out  of  what 
he  has  on  hand.  Everyone  carries 
II  jack,  so  it  is  s)ife  to  assume  tliat 
one  of  these  will  lie  available  a» 
well  03  some  form  of  chain.  If  u 
chain  of  large  size  is  not  a\'ailat>1e, 
tire  chains — particularly  extra 
cross-Iinksi — may  be  fastened  lo- 
(tether  to  answer  the  purpose.  It 
chain  is  lacking,  strong  wire,  wire 
cable,  or,  in  a  pinch,  stout  rope 
can  be  substituted.  Attach  the 
rope,  wire,  or  chain  to  a  pair  of 
opposite  spokes  of  the  wheel,  i 
jibout  two  feet  of  alack,     Draw  the  chain 'M 


GASOLINE  AUTOMOBILES  645 

the  ordinary  jspck,  that  the  combination  of  rope  and  jack  does  not 
always  work  to  advantage. 

Similarly,  the  handling  of  heavy  truck  wheels  gives  much 
trouble  even  in  the  garage,  for  they  are  so  big,  heavy,  and 
bulky  that  ordinarily  two  men  are  needed.  One  man  can  do 
the  trick,  however,  with  a  platform  or  "dolly"  like  that  shown 
in  Fig.  508.  This  consists  of  a  platform  about  4  feet  long  by 
25  inches  wide,  fitted  with  casters  at  the  four  corners.  Inside  of  the 
central  part  are  placed  a  pair  of  wedges,  one  of  which  can  be  moved  in 
or  out  by  means  of  a  crank  handle.  To  use  this,  the  wheel  is  jacked  up 
a  little  over  2  inches,  and  the  truck  pushed  under.  Then  the  movable 
wedge  is  forced  in  against  the  tire  so  that  the  two  wedges  hold  the 
wheel  firmly  and  carry  all  of  its  weight.  Then  the  casters  are  turned 
at  right  angles  so  that  the  platform  and  the  wheel  may  be  moved  off 
together.  The  truck  wheel  is  removed  in  the  usual  manner,  that  is, 
with  the  aid  of  the  wheel  puller  or  such  other  means  as  the  garage 
equipment  affords.  The  dolly  also  forms  a  convenient  means  of 
handling  the  wheel  when  it  is  put  back  on  its  axle. 

TIRES 

Kinds  of  Tires.  Broadly,  there  are  three  general  classes  of  tires: 
the  solid,  the  pneumatic,  and  the  combination  or  cushion.  The  solid 
tire  needs  little  comment  or  discussion  here — being  solely  for  com- 
mercial cars — except  in  so  far  as  it  is  used  with  some  form  of  spring 
wheel,  hub,  or  rim,  as  just  described.  Similarly,  the  cushion  tire  is 
mostly  used  for  electric  cars,  its  use  following  that  of  the  solid  tire. 

PNEUMATIC  TIRES 

The  pneumatic  tire  was  originally  developed  for  bicycle  use  and 
in  the  beginning  many  single-tube  tires  were  used.  All  of  the  tires 
used  today  have  two  parts — an  inner  and  an  outer  tube. 

Classification.  Considering  only  the  double-tube  t^pes,  there- 
fore, the  pneumatic  tire  may  be  divided  into  three  kinds:  the  Dunlop; 
the  clincher;  and  various  later  forms  brought  out  to  go  with  the  detach- 
able demountable  rims;  and  similar  devices.  These  latter  vary 
widely  in  themselves,  but  all  are  modifications  of  the  clincher  form, 
with  minor  differences  of  the  difference  in  rims. 

Dunlop.  The  Dimlop  tire,  so  named  after  the  Irish  physician 
who  invented  and  constructed  the  first  piie\rDQ»X\e  \xt^/\^\st<5k\is^ 


1^ 


the  tire  when  not  inflated.  This 
as  soon  as  the  tire  was  puncture 
a  strong  possibility  of  its  being 
east  after  it  had  been  stretched 


CUncher.  To  prevent  this  It 
and  tire  were  brouglit  out,  each 
In  the  clincher  tire,  the  fabric  is  b 
instead  of  being  left  straight  out 
formed  into  a  hump,  or  bead,  wh 
formed  in  the  rim.  The  latter  di 
only  in  having  this  deep  depres.siot 
510  shows  this,  in  which  the  mirf 


GASOLINE  AUTOMOBILES  647 

the  hard  non-stretchable  beading  over  the  edge  of  the  rim  at  one 
point.  This  done,  the  rest  is  easy.  For  this  purpose  many  tools 
have  been  bought;  some  good,  some  bad,  and  some  Indifferent.  After 
a  fashion,  alF  do  the  work,  but  that  tool  Is  best  which  performs 
the  operation  most  easily,  most  quickly,  and  with  the  least  damage  to 
the  tire  or  rim.    Fig.  511  shows  a  useful  tool  for  this  purpose. 

The  wire  wheel  and  demountable  rims,  both  allow  quick  road 
changes  of  damaged  tires,  leaving  the  work  of  tire  repair  to  be  done 
at  home  in  the  garage  with  proper  heat,  light,  tools,  and  materialn. 
This  is  rapidly  bringing  back  into  use  the  lower  price  clincher  and 
straight-side  tire  forms,  also'  many  new  tools  have  made  their 
removal  or  attachment  a  much  easier  and  more  simple  task. 

Demounb^U  Rim  Types.  Following  the  development  of  the 
clincher  tire  and  rim  until  this  fonn  of  tire  was  practically  universal, 
came  the  first  forms  of  the 
demountable  rims,  which 
consisted  of  a  detachable 
edge  or  rim  porflon,  like  the 
edge  of  the  clincher  rim  in 
section.  These  were  locked 
in  place  in  various  ways  in 
the  different  forms,  but  the 
first  demountable  rims — they 
were  called  detachable  rims 
— were  made  by  cutting  the  clincher  rims  into  two  parts,  one  of  them 
detachable.  This  allowed  of  slipping  the  tire  on  over  the  rim  In  a 
sidewise  direction,  and  did  away  with  the  stretching  and  pulling 
necessary  with  the  plain  clincher.  Since  this  was  a  tire  which  was 
detachable  more  quickly  than  the  ordinarj-  tire,  it  was  given  the  name 
"Quick  Detachable",  and  now  both  parts  are  known  to  the  trade  as 
the  Q.D.  tire  and  rim. 

yonSliid  Treads.  All  of  the  later  developments  In  the  clincher 
tire  have  been  along  the  line  of  stud<led  or  formed  treads  to  prevent 
skidding.  In  this  many  different  things  have  been  tried.  Fig.  o\2 
sliows  sections  of  many  of  the  representati\e  tires  on  the  market. 
They  are  well  known,  and  only  the  last  three  need  any  comment. 

Fig.  512  H  shows  the  Kempshall  (English)  tire  tread,  which  is 
built  up  of  a  series  of  circular  button-shaped-  depressions,  or  cups, 


wiiatever  snape  or  form  into  non 


Kig.   511.     Virions  Typ« 

built-up  structure,  shaped  like  tt 
studded  with  steel  rivets.  When 
appearance  of  a  leather-tread  tire  ^ 


GASOLINE  AUTOMOBILES  649 

advising  higher  pressures  than  those  generally  used,  stating  that 
the  people  do  not  pump  their  tires  up  hard  enough  to  get  the  best 
results  from  the  materials  in  the  tires.  There  shoulcf  really  be  no 
conSict  of  interests  here  as  the  owner  should  be  as  anxious  to  get  his 
mileage  out  of  the  tires  as  the  makers  are  to  make  good  their 
guarantees. 

Many  makers  have  stated,  as  a  result  of  their  years  of  experience, 
that  more  tires  wholly  or  partially  fail  or  wear  out  from  under- 
inflation  than  from  any  other  one  cause.  It  thus  behooves  the 
owner  of  a  car  to  look  well  to  the  pressure  in  his  tires,  not  occasionally 
but  very  frequently'.  As  the  majority  of  gages  attached  to  pumps 
in  public  garages  are  seriously  in  error,  each  motorist  is  advised  to 
purchase  his  own  gage — one  of  the  pocket  t^-pe  which  is  simple  and 
inexpensive — and  carry  it  with  him  at  ail  times. 

In  some  cases,  it  will  be  found  that  pum)>ing  the  tires  up  to  the 
makers'  specified  pressure  will  result  in  unusually  hard  riding,  and 
the  motorist  must  be  his  own  judge  as  to  whether  he  wants  to  ride 
more  comfortably  and  get  less  wear  out  of  his  tires  or  to  put  up  with 
the  discomfort  and  get  ever;'  cent  of  wear  out  of  them.  In  this 
matter,  very  few  will  choose  the  latter  course. 

Use  of  Standard  Pressure  and  Oversize  Tires.  There  is  really  a 
different  way  out.  If  the  tire  pressure  advised  by  the  maker  results 
in  too  hard  riding  for  comfort  while  comfortable  pressures  result  in 
too  much  wear,  the  motorist  is  advised  to  get  large  size  tires.  These 
on  the  same  car  will  have  a  greater  carrying  capacity  than  the  weight 
uf  the  car  by  a  large  margin.  Just  in  the  proportion  of  the  tire 
capacity  to  the  weight  of  the  car  will  be  the  pressure  recommended 
to  the  pressure  utilized. 

A  simple  example  will  make  this  clear:  Suppose,  for  instance, 
a  car  weighing  3850  pounds,  equipped  with  34-  by  4-inch  -tires,  for 
which  the  makers  claim  a  carrying  capacity  of  1 100  pounds  per  wheel 
and  recommend  a  pressure  of  95  pounds.  If  this  pressure  be  too  high 
for  comfort,  and  lower  pressures,  say  SO  or  85  pounds,  result  in  too 
.rapid  wear,  the  motorist  should  use  larger  tires.  For  instance,  a 
34-  by  4i-inch  tire  is  scheduled  to  carry  1300  pounds  per  tire,  and  the 
pressure  recommended  b  100  pounds.  The  car  weight  per  tire  is 
962  pounds,  say  970.  Changing  to  the  larger  tire  gives  a  capacity 
of  1300  pounds  per  wheel,  white  the  load  is  actually  but  970.    This 


n>u  ifti  UUUllllCU.       inUS 

1300 
X  ■■ 
The  pressure,  therefore,  in  i 
if  this  or  any  comfortable 
proper  amount  of  tire  wear  ^ 
will  be  assured. 

However,  this  propositio 
to  34-  by  41-inch  tires,  is  on' 
possibly  entirely  new  wheels,  o 
diameter  of  the  34-  by  4i-in( 
4-inch.  In  such  a  case  as  thi; 
to  a  still  larger  size,  say  35- 
without  disturbing  the  old  rir 
for  34-  by  4-inch.  This  sizi 
poundsat  100  pounds  pressure 
and  comfort  will  he  obtained 

In  general,  the  rule  for  O' 
1  inch  larger  in  exterior  diamf 
than  the  regular  sizes,  and  an 
with  the  regular  size  on  the  sai 
sizes,  as  30,  32,  34,  etc.,  are  co 
o(l<I-inch  sizes,  as  31,  :J3,*3.'),  . 
above  is  for  Anu'ricnn  or  inch 


GASOLINE  AUTOMOBILES 


rims  and  pos^bly  wheels.  A  larger  nominal  outside  diameter  will 
change  the  speed  of  the  car  and,  if  great,  may  be  too  much  for  the 
engine,  calling  for  new  gearing  as  well.  The  following  tabular 
matter  will  be  of  interest,  as  it  gives  the  changes  in  the  metric 
size  tires  which  can  be  made  without  altering  either  wheel  or  rim 
or  changing  the  gearing. 

Possible  Tire  Changes 


Itnin:    X    120  ir 


X 

90  mm 

wheels  can  be  altered  to 7 

X 

90  mm 

wheels  cu 

be  altered  to 8 

and  8 

X 

90  mm 

wheels  CM 

be  altered  to 8 

X 

90  mm 

wheels  oar 

be  altered  to S 

X 

90  mm 

wheels  can 

be  altered  to ! 

X 

lOSmm 

wheels  car 

be  altered  to 8 

X 

105  mm 

wheels  car 

be  altered  to 8 

X 

105  mm 

wheels  cai 

be  altered  to 0 

X 

120  mm 

wheels  cor 

be  altered  to 8 

X 

120  mm 

wheels  cat 

bealtcre.1  to 9 

935  n 


X    135  n 


These  can  be  used  without  changing  the  gearing  or  the  wheels, 
but  to  use  different  tires  without  changing  rims  is  another  matter. 
It  will,  therefore,  be  necessary  to  have  another  table  of  the  various 
tires  which  are  interchangeable  on  the  same  rim.  Of  the  makes 
which  are  fairly  international  In  character  may  be  mentioned  the 
German  "Michelin"  and  the  French  "Continental",  The  following 
Michelin  tires  may  be  fitted  to  the  same  rim,  the  two  tires  on  the 
same  horizontal  line  being  interchangeable  in  each  case: 

Interchangeable  HIchelin  Tires 


mm.  X  65  m 

m.  and  700  m 

n,  X  75  mm 

mm.  X  65  m 

m.  and  750  m 

n.  X  75  mm 

mm.  X  65  m 

n.  and  800  m 

Ti.  X  75  mm 

mm.  X  65  m 

m.  and  850  m 

n.  X  75  mm 

mm.  X  85  m 

m;  and  710  m 

n.  X  90  mm 

mm.  X  85  m 

at.  and  760  m 

n.  X  90  mm 

mm.  X  85  m 

n.  and  810  m 

n,  X  ao  mm 

mm.  X  85  m 

ID.  and  870  r>i 

n.  X  00  mm 

The  following  tires  of  the  Continental  make  are  interchangeable 
on  the  same  rims : 


920  X  120  and  920  X  125 

815  X  105  fit  only  105  mm.  rims 

Note.  Although  the  105  mm.  ti 
cover  can  also  be  fitted  on  the  same  ri 
810  X  90  or  810  X  100  fit  on  the  lOi 
875  X  105  fit  on  the  105  mm,  rim 
910  X  90  or  910  X  100  fit  on  the  10( 
895  X  135,  935  X  135,  and  1000  X  V. 

Speed  Changes  Due  to  Chang& 
it  might  be  well  to  say  a  few  wc 
which  a  change  in  tire  sizes  will  e 
being  so  serious  as  to  impair  the 
to  be  right  in  every  particular.  1 
ence,  the  writer  has  found  this  t 
Using  the  old  small  wJieels  and  tir 
all  grades  easily  and  make  the  i 
a  change  to  larger  wheels  and  tii 
and  gave  much  more  trouble  gen 
climber,  so  much  so,  in  fact,  that  t 
and  change  the  gearing  so  as  to  g 
engine  again  acted  satisfactorily. 

Recent  Tire  Improvements. 
notable  improvements  in  tires  wh 

Tire  Vahes.    There  have  bt 


GASOLINE  AUTOMOBILES 


653 


Inner  Tvbes.  Improvement  has  been  made  in  inner  tubes 
by  the  use  of  better  and  purer  rubber  in  much  thicker  sections. 
Some  of  these  have  a  partial  fabric  reinforcement;  others  are  made 
and  then  turned  inside  out  so  that  the  tread  portion  ia  under  com- 
pression, thus  resisting  punctures  or  internal  pressure.  Other 
designs  present  a  tube  larger  than  the  inside  of  the  tire  before  infla- 
tion; this  produces  a  truss  formation  of  the  rubber,  which  the  air. 
pressure  stiffens.    ' 

Cord  Tires.  The  real  improvement  of  value,  however,  is  the 
cord  tire.  One  form  of  this  is  shown  in  partial  section  in  Fig.  513. 
This  shows  graphically  that  the  diflference  between  this  tire  and 


Pic.  513.    Sntioi 


other  forms  is  that  the  4  to  6  or  more  la,\'er3  of  fabric  have  been 
replaced  by  two  layers  of  diagonally  woven  cord.  This  cord  is 
continuous,  rubber  impregnated,  rubber  coveredj  and,  through  its 
size,  allows  a  great  and  very  even  tension.  Lessening  the  amount 
and  thickness  of  the  fabric  has  given  a  greatee  percentage  of  rubber 
in  the  tire;  consequently,  the  cord  tire  is  more  resiUent.  The  advan~ 
tages  claimed  for  it  are:  less  power  used  in  tire  friction,  which  means 
more  power  available  for  speed  and  hill  climbing;  greater  carrying: 
capacity  in  same  size;  saving  of  fuel;  greater  mileage  per  gallon  of 
fuel;  additional  speed;  quicker  starting;  easier  steering,  thus  less 
driving  fatigue;  greater  coasting  ability;  increased  strength;  and 
practical  immunity  from  atone  bruises  owing  to  superior  resiliency^ 


prupeny  a  plain  ntn ;  and  th 

Plain  Rims.  The  fom 
type,  shown  with  tJie  Djuiih 
endless  band  with  two  ed^ 
from  coming  off  sidewiae  w 
Xothing'like  it  is  used  todi 
of  rim  used  with  single-tub 

Clincher  Rims.  Clincl 
avoid  the  weaknesses  of  th 
and,  Ijence,  it  bad  an  unum 
this  tire  remedied  was  the  t 
to  draw  away  from  the  rim 
clincher  being  made  fairly 
the  pocket,  or  groove,  forme 

It  is  the  depth  of  tins  p 
size  of  the  edge  of  the  bead  oi 
make  the  tire  hard  to  i>ut  oi 
the  previous  iliustrtftioiis  of 

Quick-Detachable  Tire 
of  handling  the  clinchtT  tire  * 
detachable  tire.  This  did  n 
tire  portion,  the  difference  b 
jmrtion  made  in  removable  f< 
made  integral  with  it.   In  som 


GASOLINE  AUTOMOBILES 


655 


gered,  rectangular  ends  into  which  these  lugs  fit.  It  requires  force 
to  spring  the  rings  together  so  the  lugs  will  go  into  the  slots,  but  once 
in  place,  the  natural  springiness  of  the  rings  holds  them  firmly  in 
place,  and  holds  the  tire  as  well. 

Figs.  514,  515,  and  516  are  given  to  show  how  this  ring  is  put 
in  place  on  a  tire.  Fig.  514  shows  the  beginning  of  the  operation, 
and  the  instructions  for  the  different  steps  will  make  them  clear. 
Thus: 

Always  start  with  left  CDii  of  the  ring!  Lock  this  in  thp  rim  as  shown  in 
Fig.  51-1,  so  that  the  end  of  the  ring  is  flush  with  the  slot  provided  for  the  aeeond 
end.  A  dowel  pin  is  provided  to  register  the  ring  in  the  proper  place.  This  must 
always  be  correctly  centered  or  the  ring  cannot  be  applied.  This  done,  the  balance 
of  the  ring  can  be  forced  over  the  flange  of  the  rJrn,  as  shown  in  Fig.  515,  with  the 
exception  of  the  locking  end.    By  means  of  the  tool,  the  lost  locking  end  can  be 


misod  and  forced  overtherimintothercceBS  provided  for  holding  the  same  in  poei- 
tioD  preparatory  to  drawing  the  ends  together,  Fig.  510.  showing  the  correct 
position  of  the  tool. 

Then  by  entering  the  two  points  of  the  tool  in  the  holes  provided  in  the 
ring,  the  ends  may  be  drawn  together,  as  shown  in  Fig.  51G,  and,  with  a  slight 
additional  leverage,  the  ends  of  the  rings  can  be  made  flush. 

Before  proceeding  further,  it  should  be  stated  that  the  object  of 
the  quick-detachable  rim  is  the  quick  removal  of  the  tire,  in  order 
to  allow  a  quick  repair  or  substitution  of  tiie  inner  tube.  On  the 
other  hand,  the  object  of  the  dcmnimtable,  reinountable,  removable, 
and  other  rims  is  the  removal  with  the  tire  of  the  rim  itself  to  allow 


year  rim.  This  rim,  as  will  h 
the  idea  being  to  remove  the 
hook  shape  with  a  shght  ridge 
This  is  on  the  fixed  side,  the 
against  it  as  a  stop.    The  tire 


GASOLINE  AUTOMOBILES 


657 


which,   in   turn,  pushes  the  locking  ring  tight  against  the  outer 

curved   part  of  the   hooked   rim.     WTien  in  this  locked   position, 

the  upper  part  of  the  flange 

hangs   over   the   locking   ring, 

so  that  it  cannot  rise  vertically, 

the  only  manner  in  which  it 

could   come  off.     This   rim   is 

shown  with  a  detachahle  tire  in 

position,  but  may  be  used  with  any  standard  clincher  tire  by  the  use 

of  extra  clincher  flanges.     Fig.  518  shows  the  rim  with  a  set  of  these 

flanges  in  position,  ready  to  take  a  standard  clincher  tire. 


Pi(.  SIO.     Univnsd  9.D,  Rim  No.  S  AiTBiijed  (or  CLncher  and  Dunlop  Tirea 

Qvick- Detachable  Number  2.  Figs.  519  and  520  show  the 
standard  quick-detachable  rim,  now  known  as  No.  2.  This  was 
adopted  by  the  Association  of  Licensed  Automobile  Manufacturers 


as  a  standard  and  gnea  the  abo\e  name.  It  has  the  feature  of 
accommodating  all  regular  clmcher,  or  Dunlop  tires.  In  Fig,  519,  it 
is  ahowD  at  A  ready  for  a  clincher  tire  and  at  B  ready  for  a  Dunlop 
tire,  the  adaptation  for  the  straight  sides  being  shown. 

The  two  parts  of  Fig.  520  show  sections  of  tires  in  place,  making 
clear  the  exact  use  of  this  reversible  flange.  A  shows  a  regular 
clincher  tire  in  place,  while  S  reveals  the  reversed  flange  in  place  with 
a  Dunlop  tire.    Both  Figs.  519  and  520  show  the  construction- of 


•//^/■////■//y/T^m^ 


fT».  S2l.     fVflioi 


*Popiil 


1  throuih  Three 

q.D.  UDivcruTltimii 

once  it  has  been  put  iii  place, 
flange  a  wider  seat  un  tlie  rim, 
wearin);. 

As  will  be  noted,  the  diffe; 
the  old  Goo<l.\t'ar  and  the  I'ni 
ring  and  the  shape  of  the  lot 
universal  rims  l>oeause  thev  ma 


■i>     i    —  ■ 


■  ■in     i 


GASOLINE  AUTOMOBILES 


659 


which  has  a  modified  Z-section,  with  a  lip  extending  over  the  outer 
edge  of  the  felloe  band.  The  third  section  differs  from  the  other  two 
only  in  having  the  outer  ring  and  locking  rin'g  combined  into  one,  and 
the  felloe  band  changed  to  suit  this.  This  combination  ring  is  held  in 
place  by  means  of  a  simple  swinging  latch,  which  is  shown  open  and 
closed  in  Fig.  522.  When  opened,  this  permits  raising  the  end  of  the 
ring,  to  which  the  shape  of  the  felloe  band  offers  no  resistance.  The 
whole  inner  ring  is  taken  off,  following  around  the  circumference  of 
the  wheel,  after  which  the  tire  is  easily  removed. 

Quick-Detachable    Clincher   Forms.     To   return   to   the   plain 
clincher  tire  and  the  Q.  D.  rim,  which  allows  of  its  ready  removal. 


W//y/^A^//A^A^A^A^^^//////y//A 


y//////^/h.9//////j. 


'////jfnfnnnna 


////////^/////i/i 


Fig.  523.     Popular  Fornis  of  9.D.  Clincher 
Rims,  Shown  in  SeotionA 


^///////y///////////////////^. 


Fig. 


vy/yy/y^/////////////////////////// 


524.     Throe  of  the  Moet  Widely  Used 
Strtiight  Side  Q.D.  Rims 


Fig.  523  shows  four  of  the  most  prominent  forms,  these  being  indi- 
cated simply  as  flat  sections  of  the  rim,  for  the  tire  is  the  same  in 
all  cases.  All  these  have  the  simple  clincher  edge  on  one  side,  with 
removable  ring  and  locking  device  on  the  other.  That  at  1  has  the 
same  locking  device  shown  at  2  in  Fig.  521,  the  Z-shaped  ring  extend- 
ing over  the  edge  of  the  band.  That  at  2  is  practically  the  same  as 
S  in  Fig.  521.  The  one  seen  at  S  is  similar  to  that  at  2  except  for  the 
detailed  shape  of  the  ring  as  well  as  the  lock  (not  shown).  The 
advantage  of  the  form  shown  at  ^  is  that  the  outer  ring  is  self-locking, 
that  is,  the  shape  of  ring  and  band  are  such  that  when  the  former 


C60 


(lASOLINE  AUTOMOBILES 


is  in  plaw  tin.-  tire  itself  lucks  it.  Its  only  disuHvantage  is  that 
it  is  harder  to  ii|)cnite  than  the  other  forms,  yet  despite  this  fact  it 
lias  hirn  rcrnTniiifnilfd  for  general  adoption  as  the  only  Q.D.  clincher 
rim  worth  ooTitimiinK. 

Q.I).  Ti/pr  fur  Siraighl  Sides.  To  close  the  subject  of  straight 
sidt  tires,  the  rims  of  tlie  quick-detachable  form  now  in  use  aside 
from  tliiise  already  shtiwii  are  seen  in  Fig,  524.  Here  these  are  seen 
to  be  iiicntical  with  /,  ^,  and  4  of  Fig.  523,  except  that  the  fixed 
side  is  arranged  for  a  straight  side  instead  of  being  made  with  a  clinch. 
Here  apiiii,  the  last  form  of  self-locking  type  has  been  recommended 
as  a  stan.lard. 

Demountable  Rims.  All,  or  practically  all.  demountable  rims 
come  under  niii.-  i>i'  two  headings — those  in  which  tlie  tire  can  be 
detached  on  the  wheel  without  demounting  (if  it  is  so  desired)  and 


GASOUNE  AUTOMOBILES 


Detroit;  Baker;  and  others,  the  wedges  carry  a  projecting  lip,  which 
makes  it  necessary  to  unscrew  the  nuts  far  enough  to  allow  the 
removal  of  the  wedge  so  as  to 
pick  this  lip  out  from  under 
the  tire-carrying  rim.  In 
others,  such  as  Empire,  S.U. 
No.  1  and  No.  2,  the  con- 
struction of  the  wedge  and 
rim  is  such  that  loosening 
them  frees  the  rim,  the  upper 
port  of  the  wedge  or  clip 
swin^ng  down  to  the  bottom, 
position  as  soon  as  loosened, 
because  of  its  heavier  weight 
and  the  fact  that  there  is  no 
projecting  edge  to  prevent  it. 
While  this  latter  construction 
makes  a  faster  operating  rim, 
it  is  an.  open  question  as  to 
whether  it  is  as  safe  as  the 
other  form.  These  two  con- 
structions are  shown  very 
plainly  in  Fig.  525,  in  which 
A  is  the  Michelin  with  lipped 
wedges,  and  B  the  Empire 
vith  plain  wedges. 

In  Pig.  526  is  shown  a 
pair  of  additional  demount- 
ables,  which  are  held  by 
the  local  wedge  method,  the 
difference  here  being  in  the 
form  of  a  wedge.  Note  that  1 
has  a  solid  clincher  rim  and 
£  a  straight  side  rim.  The 
base,  however,  is  the  same 
for  both  and,  as  will  be  seen 
by  examining  this,  has  two 
.  curves  in  its  upper  surface,  the  straight  ^de  rim  fitting  into  the  lower 


GASOUNE  AUTOMOBILES 


or  bottom  one,  while  the  clincher  form  of  rim  fits  into  the  uppci 
Note,  also,  that  the  wedges  are  the  same  for  these  two.  Thi.*  d 
the  demountable 
of  the  rim  prart 
universal  in  that 
owner  can  change 
clincher  to  straighi 
or  nVp  versa  b\'  s 
purchasing  the  exi 
of  tire-carrying 
no  change  in  the  v 
or  means  of  attach 
being  necessary, 
this  reason,  the 
band  shown  under 
two  rims  has  been 
gested  as  a  stnndai 
n<.m.,uiir,i.ic-i^«...n„u-  thr-  Bolls  dcmountables. 

!'n«-r.i.i  uf  CliiiiujiiKj  liiikiT  LiMtil  Hedge  Ti/)>e.  In  Fig.  o 
shown  tlic  ItiikiT,  which,  as  mentioned  previously,  is  of  tlie 
we<lge  type  of  denn 
able,  having  a  ti 
\crsely  split  rim  w 
must  be  renmved  I 
the  wheel  Jx-fore  the 
can  be  taken  off. 
haps  this  whole  ac 
will  be  shown  n 
clearly  by  the  prciy 
sive  series  of  views,  F 
52S  to  538,  which  si 
the  various  steps  in 
moving  and  replacin 
tire  and  tul>e  mounter 
a  Bakef  rim.  the  sanw 
"  Pry  "fl  H""  is  shown    in  section 

Ifiv  hiilts  except  the  two  nearest  the  vi 
:e  Iwisfcned  by  means  of  the  special  bi 


Fig.  520.     First,  all  the  ■ 
stem,  one  (in  eithet  avdv. 


GASOLINE  AUTOMOBILES 


■ 

P/**""^ 

1 

|| 

lit^ 

w^ 

*: 

^^aiaa^ 

Fla.  G30.    Third  Baker  Opention— Piiti 


until  the  wedges  swing  out  and, down,  as  shown  in  Fig.  528.    As 

mentioned,  previoiwlj-,  this  means  quite  a  little  loosening,  for  the 

wedges  have  a  long  lip 

which  projects  under  the 

tire-carrj'ing  rim.   When 

thia  has  been  done, 'and 

as  each  one  swings  down 

out   of   the   way,    it   is 

tightened  just  enough  to 

prevent  the  wedges  from 

swinging  back. 

This  done,  the  wheel 
b  jacked  up  off  the 
ground,  as  shown  in  Fig. 

529,  and  the  point  of  the 
tire  tool  is  inserted  be- 
tween the  felloe  band 
and  the  rim  carrying  the 
tire  at  the  point  opposite  the  valve,  where,  it  will  be  remembered,  the 
wedges  were  loosened,  and  the  rim  will  be  almost  free.  By  prying 
the  tire-carrying  rim  out- 
ward and  working  around 
it  toward  the  val\-e  and 
back  again,  it  will  finally 
be  loosened  to  a  |x»int 
where,  with  the  ^■alvc  at 
the  bottom,  the  rim  and 
tire  can  be  slipped  off 
without  lifting  it.  The 
extra  tire  and  rim  are 
now  put  in  place. 

This  is  shown  in  Fig. 

530,  where  the  re\erse  of 
the  operations  shown  in 
Fig.  529  and  just  de- 
scribed is  followed,  that 
is,  the  valve  stem  hole  is  revolved  to  the  top,  the  valve  stem  inserted, 
the  rim  pressed  into  place  all  around,  then  the  wheel  is  revolved  until 


Fw.  £32    Filth  Opetatinn— SUrtmn  to  Tn 

the  Rim  oul  of  the  Tirc-Heginning 

to  Pty  Short  End 


^s9 

Fig.  5^4.    Seventh  Operation— Prymg  und' 


Iperalion- 
EndoCRii 


the  Loom  End  of  Rim 


^imm 


GASOLINE  AUTOMOBILES  665 

the  valve  stem  comes  to  the  bottom,  so  that  the  two  wedges 
which  have  not  been  loosened  are  nearest  the  ground.  Then  the  jack 
is  let  down  and  removed,  the  whole  weight  of  the  wheel  coming  on 
the  bottom  point  where  the  wedges  are  already  tight,  never  having 
beeu  loosened. 

This  action  is  necessary  as,  with  the  weight  on  the  other  points 
where  wedges  are  still  loose,  it  would  be  necessary  to' work  against 
the  car  weight.  At  this  point,  as  Fig.  531  shows,  the  nuts  are  loosened, 
using  the  special  brace  until  the  wedges  can  be  inserted  under  the 
rim.  This  done,  the  nuts  are  tightened  to  hold  them  there.  This 
tightening  is  continued  until  the  little  studs,  or  lips,  in  the  rim  rest 
on  top  of  the  outside  edge  of  the  felloe  band,  using  the  tire  tool  to 
force  them  in,  if  necessary.  The  new  tire  carried  is  supposed  to  be 
ready  for  use,  that  is,  inflated  to  the  proper  pressure,  so  that  these 
four  actions  complete  the  work  of  making  a  roadside  change. 

When  it  is  desired  to  repair  the  tire  which  has  been  removed, 
it  is  carried  home  on  its  rim  just  as  taken  off  the  car  wheel,  and  the 
rim  is  removed  from  the  casing  as  follows:  Rim  and  tire  are  laid 
flat  on  the  garage  floor,  as  shown  in  Fig.  532,  so  that  the  outer  end 
of  the  diagonal  cut  in  the  inside  of  the  rim  which  is  farthest  from  the 
valve  stem  is  uppermost.  An  inside  plate  will  be  found  on  the  rim 
which  covers  the  two  rivet  heads  on  either  side  of  the  cut,  with  a 
central  hole  for  the  valve  stem.  This  plate  is  called  the  anchor  plate 
and  must  be  removed.  To  do  this,  begin  at  the  short  end  of  the  rim, 
which  does  not  have  the  valve  stem — as,  in  this  position,  it  will  be 
held  in  the  long  end — and  insert  the  sharp  end  of  the  tire  tool  or  a 
screwdriver  under  the  bead  or  between  the  bead  and  the  rim. 

These  two  actions,  as  shown  in  Fig.  533,  bring  the  two  short 
sides  of  the  rim  closer  together  and  thus  reduce  the  diameter.  When 
the  extreme  end  has  been  freed  in  this  way,  the  operation  is  repeated 
some  5  or  6  inches  farther  around,  that  is,  that  much  farther  away 
from  the  slit.  This  done,  a  considerable  portion  of  one  end  will  be 
free.  Then  turn  the  rim  and  tire  over  so  that  this  free  part  comes  ^t 
the  top  instead  of  at  the  bottom  and,  standing  on  the  part  which  is 
still  tight,  insert  the  tool  between  the  rim  and  the  entire  tire. 

This  frees  the  entire  end,  but,  to  make  sure,  the  tool  must  be 
moved  a  little  farther  along  so  as  to  free  more  of  it.  When  enough  has 
beerC  fceed  to  allow  grasping  it  with  both  hands,  as  shown  in  Fig.  535, 


Fig.  5^16,  the  rim  is  laiil  on  the  floor 
stem  hole  driiicil  in  it  is  raise*!,  ai 
the  beads  art-  piille<l  into  the  rim, 
together  somewhat  tightlj'  in  order 
tice,  it  soon  becomes  an  easy  matt< 
part  of  the  rim  underneath  the  tin 
The  inserted  end  of  the  rim 
end  of  the  tire  tool,  as  shown  in 


tlie  shape  of  the  joint  or  cut  in  it 
proper  place,  but  if  it  docs  not,  the 
pry  it  into  place,  or  a  hammer  ca 
drive  it  in. 

The  rim  Wing  fitted  snugly  i; 
ntatp  is  inserted,  l-'itr  !',:iK  tn  tirci--'>>f 


GASOLINE  AUTOMOBILES 


667 


tire  can  be  taken  off  the  rim.  However,  not  all  rims  are  split  on  a 
diagonal  as  is  this  one,  and  Fig.  539  is  presented  to  show  this  single 
feature  on  another  rim,  which  otherwise  is  somewhat  similar.  Here 
the  rim  is  split  at  right 
angles,  having  a  plain  thin 
rectangular  plate  A  attached 
to  the  free  end,  or  that  which 
is  removed  first,  while  the 
other  end  has  a  swinging  flat 
tapered  plate  with  a  cam- 
shaped  end  B,  the  action  of 
which  is  to  expand  the  rim 
to  its  fullest  diameter  and 
lock  it  there.  In  the  top 
figure,  it  is  locked — that  is, 
the  rim  is  expanded  as '  it 
would  be  when  in  use  and  just 
after  it  had  been  removed  for 
replacement.  When  the  rim 
is  to  be  remove<l  from  the 
tire,  the  latch  B  is  swung  out 
of  the  way,  as  shown  in  the 
lower  figure,  when  the  catch 
C  which  holds  the  two  ends 
together  can  be  opened  hy 
lifting  the  tire  with  this 
portion  at  the  bottom  and 
then  dropping  it  a  couple  of 
times.  This  done — usually 
this  action  will  be  accom- 
panied  by  the  free  end  spring 
inside  the  fixed  end — con- 
tinuation of  the  removal  is  an 
easy  matter.   The  rim  shown  ,.  t     i.     , 

''  Fm.  MU.     Serliunn  throunh  Two  Ponulur 

is  the  Stanweld  No.  20.  "f  D«no«nt«bic^u...n^h,>bi.  /ti,«» 

Comparison  of  Continuous  Holding  Ring  Tj/iw  ivilh  Local  iVedge 
Type.  To  return  to  demountable-detachable  rims,  these  ma\'  and  do 
include  a  number  of  those  quick-<letachable  forms  previously  shown 


«ii3  ucui^  Mtx-uiupiisnea  oy  ti 
band  of  a  pair  of  wedge-shapt 
made  and  applied  that  it  forn 
these  wedges,  while  the  other  i 
ring  is  used  with  the  flat  ou) 


Fic.  Ml. 


Dcmoimtoblc  Tire 


Itim  of  Fimb 


difference,  they  have  practicall 
band — that  is,  of  the  form  show 
standard  for  all  demountable-det 
example  of  the  clamping-ring  dc 
in  Fig.  541,  this  being  the  Fires 


GASOUNE  AUTOMOBILES 


it  became  known  that  the  Perlman  rim  patent  had  been  adjudged 
basic  by  the  courts,  and  that,  on  the  strength  of  this  decision,  an 
injunction  ^uid  been  issued  against  the  Standard  Welding  Company, 
of  Cleveland,  Ohio,  some  few  of  whose  rims  have  been  previously 
described.  Perlman's  original  patent  was  applied  for  on  June  29, 
1906,  and,  in  addition  to  this  record,  the  fact  was  established  that 
the  owner  had  a  Welch  car  which  had  traveled  over  150,000  miles 
and  on  which  were  a  set  of  the  original  rims.  The  case  dragged 
through  the  courts  and  was  discontinued  some  seven  or  eight  years 
ago.  Perlman  persisted,  however,  although  he  had  to  revise  and 
alter  his  application  many  times;  the  basic  patents  were  finally 
allowed,  and  issued  to  him  in  February,  1913.  This  means,  of  course, 
that  the  patent  will  not  expire  until 
the  year  1930. 

Perlman's  locking  elements  and 
the  principle  involved  are  shown  in 
Fig.  542,  which  is  a  section  through 
the  rim  and  felloe.  In  Perlman's  suit, 
it  was  claimed  that  the  wedge  end  of 
the  bolt  which  was  covered  in  his 
patent,  included  all  wedge-operating 
rims,  whether  actuated  from  the 
center,  as  in  Fig.  542,  or  from  the  side. 
This  contention  was  supported  by  the  ^*"''^"'  ^'"''''"'  "•"'" 

court,  and  negotiations  are  now  in  process  between  Perlman  and  man,^' 
manufacturers  of  the  so-called  local  wedge  tj-pe  of  rim.  As  this  would 
appear  to  cover  all  the  rims  shown  and  described  in  Figs.  525  to  541 , 
inclusive,  the  influence  of  this  decision  upon  the  industry  can  be 
imagined.  Moreover,  the  length  of  time  which  this  basic  patent  ha.-! 
to  run  precludes  the  possibility  of  delaying  action  by  prolongation 
of  suits,  as  has  been  done  in  similar  cases.  |A  notable  example  of 
^is  is  the  case  of  the  Selden  automobile  patents,  which  were  fought 
on  one  ground  or  another  o\'er  a  long  period  of  years. 

Standard  Sizes  of  Tires  and  Rims.  As  might  have  been  noted 
in  going  over  the  above  discussion  of  tires,  plain  rims,  detachable 
rims,  and,  finally,  demountable  rims,  all  these  different  coustructicms 
require  widely  differing  wheel  sizes.  It  has  been  proposed  to  stand- 
ardize wbeeb,  that  is,  the  outside  diameter  of  the  felloe  and  with 


n    "3,      TypI,.,  ,.,||^,  ^^j    _ 

by4-mcl,for.30-b,v3Hnch!: 


GASOLINE  AUTOMOBILES 


671 


widely  used  demountable  rims,  depicting  the  band  and  rim  in  each 
case.  The  drawing  should  be  read  crosswise,  each  horizontal  line 
showing   the   differences   to    be 


found  in  the  makes  mentioned  in 
that  particular  tire  cross-section 
size.  Thus,  the  D  sections  show 
the  differences  for  3i-inch  tires, 
E  those  for  4-inch  tires,  F  those 
for  41-  and  5-inch  tires,  and  G 
those  for  h\-  and  6-inch  tires, 
rims  for  which  are  not  produced 
by  all  makers. 

Other  Removable  Forms. 
Outside  of  the  regular  range  of 
wood  wheels  and  the  standard 
tires  for  them,  any  different  wheel 
calls  for  a  different  treatment. 
As  has  already  been  mentioned 
under  the  subject  of  Wire  Wheels, 
few  of  these  have  anj-thing  but  a 
solid  one-piece  clincher  rim;  first, 
because  the  wheel  itself  is  remov- 
able, thus  making  it  as  easy  to 
change  wheels  as  to  change  rims 
in  the  ordinary  case;  and  second, 
to  save  weight  and  complication. 

DemounUAlefor  Wire  Wheels. 
However,  demountable  forms 
have  been  produced  for  wire 
wheels,  one  being  shown  in  Figs. 
544  and  545.  This  is  the  G-R-C 
double  Q.D,  rim  as  the  makers 
prefer  to  call  it,  in  action  a  de- 
mountable-detachable form,  the 
clincher  rim  being  of  the  straight 
split  type,  in  fact,  a  Stanweld 
No.  20.  This  is  made  with  a 
double   wedging  surface  on   the 


/^^^^ 


dwid  luOpmtMB 


672 


GASOLINE  AUTOMOBILES 


outside  and  a  single  one  ou  the  iiiuide.  The  latter  cuntacta  witli 
another  on  the  false  rim  to  which  the  wire  spokes  are  attachw!,  as  dots 
also  the  inner  wedging  surface  on  the  outer  wedge.  The  outer  wedg^ 
ing  surface  is  made  so  as  to  come  just  above  a  fairly  dpep  slot  in  the 
false  rim.  In  this  is  placed  a  ring  with  a  double  wedgt-shaped  upper 
edge  and  a  square  lower  edge.  This  ring  is  Split  at  one  i>oiiit  and 
locked  in  the  highest  position  at  the  [mint  diaiiietrically  opposite. 

At  the  spht  point,  a  pair  of  bent-arm  levers,  Kig.  .54-4,  arc 
connected  to  the  two  ends.  Attached  to-a  middle  i>oint  of  each  of 
these  is  one  end  of  an  inverted  L- 
fihaped  member,  llic  center  and 
up(»er  part  of  whieli  form  h  bear- 
ing for  a  locking  stud,  which  is 
attached  to  one  end  of  the  rii^;. 
Above  this  is  placed  a  nut.  As 
will  be  noteil,  this  forms  a  toggle 
motion,  th«  action  of  which  is 
111  expand  tJie  whole  ring  when 
tlic  nut  is  screwed  down  and  to 
oontracl    it    when    the    nut    is 


GASOLINE  AUTOMOBILES  673 

up  the  inclme  at  the  bottom  of  the  cup,  against  the  wedge  on  the 
underside  of  the  rim,  the  amount  of  pressure  exerted  depending 
solely  upon  that  applied  to  the  bolt  head.  As  the  two  wedge  shapes 
oppose  each  other,  this  holds  the  rim  as  firmly  as  is  possible.  It 
will  be  noted  that  this  construction  does  away  altogether  with  the 
use  of  felloe  bands  or  false  rims  used  on  other  forms  of  rims  or  wKeels, 
thus  saving  much  weight.  Moreover,  a  great  part  of  the  weight 
is  saved  at  the  outside,  where  the  flywheel  effect  of  rapid  rotation 
is  thus  lessened.  Moreover,  the  absence  of  additional  metal  here 
would  give  the  tire  more  chance  to  radiate  its  heat,  and  thus  would 
preserve  it  better.  This  construction,  considering  its  many  advan- 
tages, should  have  a  wide  use. 

Similarly,  with  all  demountable  rims,  the  tendency  is  toward 
wider  use,  with  which  comes  lower  cost,  as  well  as  a  better  under- 
standing of  their  use,  abuse,  attachment,  and  detachment.  With 
the  standardization  of  tires  to  a  few  standard  sizes,  say  9  instead 
of  54,  it  will  be  only  a  few  years  before  all  kinds  of  rims,  including 
demountables,  will  be  standardized,  at  which  time  the  latter  will 
come  into  universal  use. 

TIRE  CONSTRUCTION 

Composition  and  Manufacture.  Tires  consist  of  two  parts,  the 
tube  and  the  shoe,  or  casing.  The  former  is  a  plain  ring  of  circular 
cross-section,  made  of  pure  rubber,  containing  an  air  valve,  and  is 
intended  only  to  hold  the  air.  The  shoe,  or  casing,  on  the  other 
hand,  provides  the  wearing  surface,  protects  the  air  container  within 
from  all  road  and  other  injuries,  and  constitutes  or  incorporates  the 
method  of  fastening  itself  to  thei  wheel.  In  its  construction  are 
included  fabric — preferably  cotton — some  pure  rubber,  and  much 
rubber  composition,  the  whole  being  baked  into  a  complete  unit  by  heat 
in  the  presence  of  sulphur,  which  acts  somewhat  as  a  flux  for  rubber. 

Considering  a  typical  tire,  there  enters  into  its  make-up,  starting 
from  the  inside,  six  or  seven  strips  of  frictional  fabric,  that  is,  thin 
sheets  of  pure  gum  rubber  rolled  into  intimate  contact  with  each 
side  of  the  cotton,  making  it  really  a  rubber-coated  material.  Next, 
there  is  the  so-called  padding,  which  is  more  or  less  pure  rubber,  has 
a  maximum  thickness  at  the  center  of  the  tread,  and  tapers  off  to 
nothing  at  the  sides,  but  usually  carrying  down  to  the  beading. 


FiK.  M7.     Section  Ihroiuili  Ammbled; 


GASOLINE  AUTOMOBILES 


C75 


triangle  resting  on  its  base;  around  the  wheel  it  is  curv'ed  to  fit  the  rim'. 
The  method  of  attaching  the  tire  has  a  considerable  influence  on  bead 
construction,  since,  in  the  clincher  type  of  tire,  in  which  the  shoe  must 
be  stretched  on  over  the  rim,  the  bead  must  be  extensible  in  order  to 
insure  easy  mounting.  In  the  quick-detachable  and  striight-side 
forms  of  tire  there  is  no  need  for  this  stretching,  so  the  bead  can  be 
made  of  stiff  and  rigid  material  as  well  as  cut  down  somewhat  in  size. 

The  straight-side  or  Dunlop  type  of  tire  is  seldom  made  with 
much  of  any  bead,  the  layers  of  fabric  being  carried  straight  down. 
A  more  modern  form  of  tire  has  a 
pair  of  woven-wire  cables  incor- 
porated in  the  bead  to  m^e  it 
stiffer  and  stronger,  and  this  is 
said  to  ha\'e  been  very  successful. 
As  has  been  pointed  out  pre- 
viously, this  could  be  done  only 
with  the  quick-detachable  form, 
not  with  the  clincher  type. 

In  both  the  clincher  and  the 
quick-detachable  forms,  the  bead 
holds  the  tire  to  the  wheel  by 
means  of  parts  of  the  rim,  which 
bear  on  it  from  above,  as  well  as 
side  wise,  the  internal  pressure 
when  the  tire  is  inflated  pressing 
it  against  these  p>arts  very  firmly. 

In  both  the  clincher  and  the  quick-detachable  forms,  the  bead 
holds  the  tire  to  the  wheel  by  means  of  parts  of  the  rim,  which  bear 
on  it  from  above,  as  well  as  sidewise,  the  internal  pressure  when 
the  tire  is  inflated  pressing  it  against  these  parts  very  firmly. 

Tire  Valves.  In  Fig.  547  there  is  shown  a  section  through  the 
tire  valve  but  on  a  small  scale.  As  this  is  a  very  important  part 
and  little  understood,  a  larger  view  is  shonTi  in  Fig.  54S.  This  is  in 
two  parts,  A  at  the  left  showing  the  valve  closed,  and  B  at  the  right 
indicating  the  position  of  the  various  parts  when  the  valve  is  open. 
Note  that  the  lower  part  of  the  valve  is  hollow,  so  that  air  inside  of 
the  tire  has  access  to  the  valve  seat.  Note  that  the  valve  is  held 
down  on  this  by  the  threaded  portion  above  it.    This  valve  seat 


which  normally  is  held  up  agai 
spring,  this  being  strong  enough 
can  pass  between  the  two.  Ti 
tightness.  The  spring  must  be 
together;  and  the  surfaces  mu:j 
held  together,  no  air  can  get  thr 

Actum  of  i'alre.  The  actii 
is  pumped  In,  it  passes  down 
meets  the  projection,  which  it  f 
the  spring  and,  when  there  is  ai 
internal  air.  As  soon  as  this  is  ] 
if  the  external  pressure  is  stoppe 
pump,  the  spring  and  the  intc 
back  into  place,  and  no  air  can  e 
of  the  pump,  this  is  repeated,  th< 
tire  is  filled. 

Leaky  }'alrex.  It  will  be  nc 
projection,  and  \'a!ve  seat,  the  ; 
valve  tight.  Thus,  when  a  valvi 
part  or  parts  of  it  are  not  in  gc 
screwed  down  far  enough,  air  ca 
so  that  leakage  mH\-  he  remedied  1 
down  into  tlie  stem.    If  the  valve 


GASOLINE  AUTOMOBILES  677 

by  taking  out  and  cleaning  the  spring,  also  stretching  it  as  much  as 
possible.  In  general,  however,  the  b^t  plan  of  action  with  a 
troublesome  tire  valve  is  to  screw  it  out  and  put  in  a  new  one.  These 
can  be  bought  for  fifty  cents  a  dozen,  and  every  motorist  should 
carry  a  dozen  in  a  sealed  envelope,  also  a  combination  valve  tool, 
Ai'lien  trouble  arises  with  the  valve,  or  a  tire  leaks  down  flat  with 
no  apparent  cause,  screw  out  the  valve  with  the  tool,  screw 
in  a  new  one,  make  sure  it  is  down  tight,  and  pump  up  again.  Tlie 
few  cents  it  will  cost  to  throw  away  a  valve,  even  if  it  should  hap- 
pen to  be  good,  will  be  more  then  compensated  for  by  the  time 
saved.  Another  point  is  that  the  whole  valve  assembly  is  so  very 
small  that  it  is  difficult  to  handle. 

Washing  tires  often  is  a  good  practice,  since  water  does  them  no 
harm,  while  all  road  and  car  oils  and  greases  will  be  cleaned  off, 
nearly  all  of  these  being  injurious.  Frequent  washing  will  also  serve 
to  call  the  attention  of  the  owner  to  minor  defects  while  they  are  still 
small  enough  to  be  easily  repaired,  and  thus  they  are  prevented  from 
spreading.  When  not  in  use,  tires  should  be  wrappe<l,  so  as  to  be 
covered  from  the  light,  and  put  away  in  a  dry  room  in  which  the 
temperature  is  fairly  constant  the  year  round.  They  will  not  stand 
much  sunliglit,  nor  many  changes  in  temperature.  Cold  hardens 
the  tires  and  causes  the  rubber  to  crack.  Heat  has  a  somewhat 
similar  effect  and  also  draws  out  its  life  and  spring. 

In  general,  of  all  things  to  be  cared  for  and  repaired  promptly-, 
no  one  thing  is  of  more  importance  than  the  tires.  If  this  rule  is 
kept  in  mind,  better  satisfaction  in  the  use  of  the  car  will  result. 
So,  too,  with  other  repair  work;  If  tools  and  appliances  are  made 
available  and  repairs  made  as  soon  as  needed,  the  car  will  be  better 
understood  and  give  more  satisfaction  than  if  the  opposite  course 
be  pursued.  A  few  months  of  use  of  a  car  will  do  more  to  emphasize 
this  than  any  amount  of  talk.  Keep  your  car  in  good  condition 
and  you  will  reap  the  benefits  of  the  little  work  you  do  upon  it. 

TIRE  REPAIRS 

Repair  Equipment 

Vulcanization  of  Tires  for  Repair  Man.    In  practically  all  of  the 

following  material  the  point  of  view  is  that  of  the  profe^ional  repair 

man,  or  of  the  garage  man  about  to  take  up  tire  repairs,  as  dis- 


678 


GASOLINE  AUTOMOBILES 


tinguished  from  that  of  the  average  owner  or  amateur  lepamr. 
lesser  tire  injuries  and  their  repairs  are  handled  from  ao  ami! 
standpoint  in  another  part  of  this  work. 

Vulcanization,  to  the  unitiated,  sounds  verj'  mystmous, 
it  really  is  nothing  more  or  less  than  cooking,  or  curing,  raw  g 


rubber.  Iii  the  processes  of  manufacture  a  tire  is  cooked,  or  cup 
all  the  component  parts  supposedly  being  united  into  one  compi' 
whole.  A  tire  is  repaired  preferably  with  raw  gum  or  fabric  prepai 
with  raw  gum,  and,  in  orfler  to  unite  this  to  the  tire,  vulcaniaat 
ir  curing  is  necessarv-    TWe  c\wvu?„  in  addition  to  uniting  the  pi 


MuasisfA. 


GASOLINE  AUTOMOBILES  679 

properly,  gives  the  proper  strength,  or  wear-resisting  qualities,  which 
raw  rubber  lacks. 

Types  of  Vulcanizing  Outfits.  Shaler  Vulcanizer.  This  curing, 
or  cooking,  is  done  by  the  application  of  heat,  in  a  variety  of  ways. 
Generally,  very  small  individual  vulcanizers  have  a  gasoline  or 
alcohol  cavity,  holding  just  enough  of  the  liquid  so  that  when  lighted 
and  burned  the  correct  temperature  will  be  reached  and  held  for  the 
correct  length  of  time.  The  larger  units  are  operated  by  steam  or 
electricity;  the  latter  is  preferred  for  its  convenience,  but  the  former  is 
used  by  the  majority  of  repair  men.  The  source  of  heat  is  immaterial 
so  long  as  the  correct  temperature  is  reached  and  maintained  for 
the  right  lengh  of  lime.  Too  hot  a  vulcanizer  will  burn  the  rubberr 
while  too  low  a  temperature  will  not  give  a  complete  cure. 

•  

For  the  average  small  repair  man,  the  outfit  shown  in  Fig.  549 
will  do  very  nicely,  at  least  to  start  with.  This  will  handle  a  single 
casing  or  six  tubes,  or  in  a  press  of  work,  both  simultaneously.  This 
outfit  is  operated  by  gasoline,  contained  in  the  tank  shown  above 
at  the  right,  but  the  same  outfit  can  be  had  with  pipe  arrangements 
for  connecting  to  a  steam  main,  or  for  electric  heating.  In  the  case 
of  either  gasoline  or  steam,  there  is  an  automatic  temperature  con- 
trolling device  which  is  a  feature  of  the  Shaler  apparatus.  As  shown, 
casings  are  repaired  by  what  is  known  as  the  "wrapped  tread  method", 
the  repair  being  heated  from  both  inside  and  outside  at  once,  the 
outside  being  wrapped.  Tubes  are  handled  on  the  flat  plate,  shown 
in  the  middle  of  the  framework,  the  size  of  which  is  4^  by  30  inches, 
this  being  suflBcient,  so  the  makers  say,  to  handle  six  tubes  at  once. 

Haywood  Vulcanizer,  For  larger  work,  a  machine  something 
like  the  Ha^'wood  Master,  shown  in  Fig.  550,  is  excellent.  This  is 
a  self-contained  unit,  carrying  its  own  gasoline  tank,  steam  generator, 
and  other  parts.  It  handles  four  casings  at  once,  while  the  tube 
plate  G,  5  by  18  inches,  is  large  enough  for  from  three  to  four  tubes, 
according  to  the  allowance  per  tube  made  in  the  Shaler  outfit.  The 
separate  vulcanizers  are  not  designed  for  the  same  part  of  a  casing, 
a  side  wall  and  bead  vulcanizer  being  shown  at  /),  a  sectional  vul- 
canizer for  large  sizes  at  E^  a  sectional  vulcanizer  for  small  and 
medium  sizes  at  F,  and  a  side  wall  and  bead  vulcanizer  for  both 
clincher  and  straight-side  tires  at  H,  The  gasoline  tank  is  marked 
C,  with  vertical  pipe  in  which  is  the  gasoline  cut-oflF  valve  K.-    This 


GASOLINE  AUTOMOBILES 


and  3J-inch  tires,  and  reliniDg  mold  for  4r,  4)-,  5-.  and  5J-inch  casings 
come  with  the  device. 

This  outfit  with  the  extra  molds,  described  but  not  shown,  gives 
a  very    complete   equipment  for  the  small  shop    doing   average 


Flc.  551. 


if  Vuloaiiini  Mold 


repairing.    In  fact,  when  a  shop  outgrows  this  type  of  equipment, 
it  must  specialize  in  tire  work  and  purchase  special  equipment. 

Separate  Casing  Molds  for  Patch  Worit.  In  the  way  of  sepa-  ■ 
rate  molds  for  casings,  an  excellent  example  of  the  localized  heat 
type  is  shown  in  Fig,  551 .  By  this  is  meant  the  form  designed  to 
vulcanize  a  small  short  section  of  a  tire.  The  illustration  shows 
five  sections  capable' of  handling,  respectively,  2i-,  to  3-inch  (motor- 
cycle), 2J-  to  3-inch  (small  car),  3^-  to  4-inch,  4J-  to  5-inch,  and  5^-  to 
6-inch  tires,  thus  covering  the  entire  range.  These  molds  have  a 
special  arrangement  in  that  the  heating  portion  is  divided  into  three 
sections,  into  each  of  which  steam  can  be  admitted  separately.  This 
allows  the  use  of  one,  two,  or  all  the  sections,  according  to  the  nature 
of  the  repair. 

In  Fig.  552  is  shown  how  it  is 
possible,  with  this  apparatus,  to  vul- 
canize the  tread  portion  only  by 
admitting  steam  solely  to  the  larger 
bottom  steam  chamber  around  the 
tread,  similarly,  with  the  right-hand 
head  or  side  wall  or  the  left-hand  bead 
or  side  wail.  When  a  complete  sec- 
tion is  to  be  vulcanized,  all  sections 
are  opened.  The  importance  of  this 
will  be  realized  in  a  simple  consideration  of  the  fact  that  the  tire  itself 
has  already  been  vulcanized  and  further  heat  is  not  only  not  good  for 
it,  but  is  distinctly  bad,  as  H  deteriorates  the  rubber.    Where  the  heat 


FiK.  5S2.    Section  i 


"'""■" '■"'W«lfl,i„tl,,,,i„,, 


GASOLINE  AUTOMOBILES 


two  casings  at  a  time,  and  at  least  two,  perhaps  four,  kettles  full 
an  hour,  that  is,  from  40  to  75  ca»ngs  a  day,  it  becomes  necessary 
to  use  a  larger  tj-pe  of  kettle,  made  in  vertical  types  only.  These 
consist  simply  of  large  round  steel  shells  with  hinged  heads,  into 


Fig.  oij.     hlislcr  Llvt[i«1I>  UuiWd  Inudt  Culni  Form 

which  the  tires  can  be  rolled  and  piled,  after  which  steam  is  admitted  to 
the  whole  interior.  They  vary  in  size  from  36  inches  inside  diameter 
by  24  inches  in  length  to  48  inches  diameter  by  40  inches  in  length. 

Inside  Casing  Forms.  Another 
requisite  of  the  tire  specialist  is  an 
inside  casing  form,  such  as  is  shown 
in  Fig.  555,  or  something  similar. 
Many  tire  repairs  are  inside  work, 
and  even  on  those  which  are 
external,  it  is  important  to  ha^'e  an 
inside  form  against  which  the  tire 
can  be  pressed  and  firmly  held  while 
vulcanizing.  This  particular  form 
is  heated  by  electricity,  the  wires 
being  shown  at  the  left;  it  is  14 
inches  long  and  has  an  external 
shape  to  fit  the  inside  of  all  casings. 

Side-Wall  Vulcanizer.    A  shop  doing  a  great  deal  of  work  can 
use  to  good  advantage  the  side-wall  vulcanizer  shown  in  Fig.  556. 


iide-WiUl  Vulcwum 


084 


tlASOLINE  AUTOMuBlLKS 


It  has  a  single  central  member  through  which  the  steam  passes,  and 
aho  has  bolted-on  w\t:  plates,  the  insides  of  which  are  formed  to  suit 
either  clincher  or  straight-side  tires.  In  the  figure,  the  side  plates  are 
not  both  in  place,  one  being  siiown  on  the  work  table  below.  The 
brace  shown  is  used  to  remove  the  damping  luits  quickly  and  easily. 
This  form  is  very  useful  on  all  side-wall  or  bead  operations.  It  applie.i 
greaterpressurealong  these  parts  of  the  tire  than  an  air  bag;  it  exactly 


OASOLINt;   AUTOMOBILRS 


wlieii  putting  on  a  complete  new  tread  the  mold  must  be  used  three 
times.  The  section,  Fig.  558,  is  numbered  as  follows:  casing,  2; 
inner  mold,  1;  new  tread  to  be  vulcanized,  3;  vulcanizer  proper,  4; 
clamp,  5;  and  steam  space  within  which  the  beating  is  done,  6. 

Layouts  of  Equipment  There  are  two  wa\-s  of  installing  an 
outfit  somewhat  like  that  just  described,  namelj',  by  the  non-return 
system  and  by  thp  gravity- 
return  system. 

Non-Return  Layout.  A 
typical  installation  according 
to  the  non-return  system  is 
-shown  in  Fig.  559.  A  steam 
trap  must  be  placed  in  the 
system  to  remove  the  water 
and  discharge  it  either  into 
the  sewer  or  into  a  tank  so 
that  it  can  be  used  again. 
In  the  figure  there  is  shown  a 
tube  plate,  a  three-<ravity 
Sectional  vulcanizer,  two  in- 
side molds,  and  a  medium 
size  kettle  of  the  vertical  tjpe 
placed  in  order  from  right 
to  left.  A  pres.'iure-reducing 
valve  is  shown  which  permits 
the  use  of  a  higher  pressure 
in  the  boiler,  thus  maintain- 
ing an  even  steady  pressure 
on  the  vulcanizers  regardless 
of  fluctuations  at  the  boiler.  ompan^.      tanapoin,      una 

GraeUy- Return  Laymd.  When  the  coil  steam-generator  or  flash 
type  of  boiler  is  used,  the  gravity-return  system  is  utilized,  this  being 
a  method  of  piping  by  means  of  which  the  condensed  steam  is  returned 
to  the  coil  heater  to  be  used  over  again.  This  makes  it  necessary  to 
set  the  apparatus  so  that  the  water  of  condensation  will  run  back  to 
the  coil  heater,  which  means  that  the  pieces  must  be  in  a  series,  each 
successi\e  one  being  set  a  little  lower  down  to  the  boiler.  Figs, 
500  and  5GI  show  a  side  view  and  plan  view,  respectively,  of  a  small 


GASOLINE  AUTOMOBILES 


GASOUNE  AUTOMOBILES 


plant  arranged  on  this  plan.  The  outfit  consists  of  the  coil  heater, 
which  may  be  fitted  to  bum  gas  or  gasoline,  two  inside  molds,  a  large 
tube  plate,   and   a   three-cavity   sectional  vulcanizer.     The  outfit 


Flf.  SW.    ElcTBtioa  of  anvity-ltetura  Vulc 


differs  from  Fig.  559  only  in  the  absence  of  the  kettle;  on  the  other 
hand,  the  tube  plate  in  Fig.  560  is  larger. 

Small  Tool  Equipment.  In  addition  to  these  larger  units,  the 
well  equipped  tire  repair  shop  should  have  a  considerable  quantity 
of  small  tools,  among  the  necessities  being  those  shown  in  Fig.  562, 
At  A  is  shown  a  flat  hand  roller  and  at  ff  a  conca\'e  roller.  C  shows 
an  awl,  or  probe,  which  is  used  for  opening  air  bubbles  and  sand  blis- 
ters. /)  is  a  smooth  stitcher;  F  a  rubber  knife,  of  which  two  sizes  are 
advisable,  a  large  and  a  small;  and  G  a  lO-inch  pair  of  shears  for 


trimming  inner  tube  holes,  cutting  sheet  rubber,  etc.  //  is  a  steel 
wire  brush  for  roughing  casings  by  hand;  a  preferable  form  is  a 
rotary  steel  wire  t\pe  driven  by  power  at  high  speed.     /  is  a  similar 


GASOLINE   A UT< )M< )H I  !.!■> 


H-iri-  briisli  fur  roughing  tubes;  and  J  another  bnisli  with  luiigei 
wires,  also  for  roughing  casings;  K  is  a  tread  gage  for  markiiig 
casings  to  be  retreadcd;  and  L  &  fabric  knifo  necessarj-  in  stepping 
down  plies  of  fabric.  M  is  a  pair  of  plug  pliers  for  placing  patches 
inside  of  small  tube  repairs;  iV  ia  a  ctineiit  brush  for  heavy  casing 
cement,  another  very  much  smaller  and  lighter  one— preferably  of 
the  camel's  hair  typi — being  used  for  tube  cement.     0  is  a  hand 


GASOLINE  AUTOMOBILES  689 

open  when  working  inside;  a  casing  mandrel  or  tire  last  of  east  iron 
for  holding  a  casing  when  making  repairs;  a  tread  roller  for  rolling 
down  layers  of  raw  stock  evenly  and  quickly;  a  considerable  amount 
of  binding  tape;  thermometers;  and  such  motor-driven  brushes, 
scrapers,  etc.,  as  the  quantity  and  quality  of  the  work  warrant. 

Materials.  Each  repair  shop  must  carry  such  a  supply  of  tire- 
repairing  material  as  the  nature  and  quantity  of  its  business  demands. 
Among  other  things  may  be  mentioned:  Tread  stock,  rebuilding 
fabric,  single-friction  fabric,  cushion  stock,  breaker  strips,  single- 
cure  tube  stock,  combination  stock,  cement,  quick-cure  cement, 
soapstone,  valve  bases,  valve  insides,  valve  caps,  complete  valves, 
vrdcanizing  acid,  various  tube  sections,  tire  tape,  cementless  patches, 
as  well  as  many  other  tire  accessories  to  sell.  Many  good  tire-repair 
shops  find  a  legitimate  use  for  special  tire-repairing  preparations  on 
the  order  of  Tire-Doh. 

Inner  Tube  Repairs 

In  general,  all  tire  repairs  come  under  one  or  more  of  the  following 
headings;  puncture;  blowouts;  partial  rim  cut  or  rim  cut  all  around; 
and  retreading  or  recovering,  and  relining. 

Simple  Patches.  Under  the  heading  of  punctures  are  handled 
all  small  holes,  cuts,  pinched  tubes,  or  minor  injuries.  Generally, 
these  can  be  repaired  by  putting  on  a  patch  by  means  of  cement, 
or  with  cement  and  acid  curing.  When  well  done,  this  method  is 
effective.  This  kind  of  a  job  seldom  comes  to  the  repair  man,  and, 
when  it  does,  it  is  principally  because  the  owner  is  too  lazy  to  do  the 
w^ork.  About  the  only  two  cautions  necessary  are  relative  to  clean- 
liness and*  thoroughness.  The  tube  and  patch  should  be  thoroughly 
cleaned.  Again  the  patch  should  be  large,  well  cemented,  and  the 
cement  allowed  to  dry  until  just  sticky  enough  to  adhere  properly. 
Many  a  simple  patch  of  this  kind  has  been  known  to  last  as  long  as  the 
balance  of  the  tube. 

Large  Patches.  ^  Cleaning  the  Hole.  Whenever  the  hole  or 
cut  is  large,  it  is  recommended  that  the  repair  be  given  more  serious 
attention  and  vulcanized.  The  ragged  edges  of  the  rubber  should 
be  trimmed  smooth  with  the  tube  shears  or  knife,  the  minimum 
amount  of  rubber  being  cut  away.  The  hole,  however,  should  be 
made  large  enough  to  allow  the  insertion  of  an  inside  patch.    Then 


690  GASOLINE   AUTOMODILKS 

thi'  tube  arounrf  the  holt"  shoulri  be  clMtoeii  thorniighly.  This  is  best 
flnnc  with  a  doth  wet  with  gasoline,  cleaTiing  not  only  the  outside 
!>ut  the  inside  around  tlie  hole  and  at  the  edges.  In  order  to  make  a 
gc»o<I  job  of  this,  it  shoulit  be  gone  over  several  times;  the  larger  the 
liole  the  more  care  shouKl  be  used  in  cleaning  around  it. 

Preparing  the  Patch.  Having  the  hole  well  cleaned  ant!  ready, 
these  cleaned  parts  should  be  painted  with  two  coats  of  vulcanizing 
cement,  which  is  allowed  to  dry.  This  must  be  thoroughly,  not  partly, 
dry.  Then  the  jiroper  patch  is  selected,  the  smaller  size  being 
sufficient  for  small  patches,  while  in  the  case  of  large  repairs,  the 
patch  should  be  from  5  to  1  inch  larger  all  around  than  the  hole. 
If  this  is  not  a  prepared  patch,  one  side  should  be  cemented  just  as 
tlic  tube  was  previously.  If  a  prepared  patch  is  used,  the  semi- 
cured  side  should  be  jilaced  in,  tliat  is,  with  tlie  sticky  or  uncured 
side  toward  the  tulie  from  the  inside.' 

When  the  cement  on  the  patch  is  just  sticky  euougli.  it  nhould  be 
inserted  and  the  tube  pressed  down  against  it  all  around,  slowly 
and  carefully  so  as  to  ^et  good  adhesion.  Next  the  cavity  about 
the  inside  patch  is  filled  «ith  gum  or  pure  rubber,  preferably  in  sheet 
form  as  it  comes  for  this  purpose.  This  is  filled  in  until  the  surface 
k  fliKl>       It   i<  nrof*-rnbl-'  tn  »«•  a  liHlp  vnlfBni^mcr  rpmenf  tn  KnU 


GASOLINE  AUTOMOBILES 


691 


a  slight  indentation  from  the  point  of  a  lead  pencil.  This  is  a  good 
test  to  use  at  first,  although  after  a  short  experience,  the  workman 
will  be  able  to  judge  of  the  condition  from  the  feeling,  color,  and 
general  appearance  of  the  patch. 

When  the  size  of  the  plate  is  small,  the  tubes  should  be  held  up 
above  it  out  of  the  way,  partly  to  allow  the  full  use  of  the  plate 
surface,  but  also  to  keep  the  tubes  from  being  damaged. 

Inserting  New  Section.  Preparing  the  Tubes.  In  case  th^ 
damage  to  the  tube  is  too  great  to  permit  the  use  of  a  patch,  for 
instance,  in  case  a  blowout  makes  a  wide  hole  perhaps  7  inches 
or  more  long,  in  an  othe^^'ise  good  tube,  it  is  advisable  to  cut  out 
the  damaged  section  and  insert  a  new  section  in  its  place.  Somer 
times  old  tubes  of  the  same  size  can  be  used  for  this,  but,  if  not, 
sections  can  be  purchased  from  the  larger  tire  and  rubber  companies. 


\    \ 


Fig.  563.     Sketch  Showing  Method  of  Iiucrting  New  Section  in  Innide  Tube 


In  the  repair,  proceed  as  follows:  After  cutting  out  the  damaged 
section,  bevel  down  the  ends  very  carefully,  using  a  mandrel  to 
work  on  and  a  very  sharp  knife.  As  the  appearance  and,  to  a  large 
extent,  the  value  of  the  repair  will  depend  upon  these  lx»vele<l  ends, 
this  should  be  done  in  a  painstaking  manner.  •  Next  select  the  tube 
section  and  cut  it  to  size,  that  is,  from  5  to  G  inches  longer  than  the 
section  which  was  cut  out  and  which  this  patch  is  replacing.  This 
allows  2i  to  3  inches  for  the  splice  at  each  end.  '  Bevel  the  ends  of 
the  tube  as  well,  and,  after  l>eveling  ail  four  ends,  roughen  thern 
with  a  wire  brush  or  sandpaper. 

Making  the  Splice.  Having  the  tuixf  and  repair  section  i>evelwi 
and  buffed,  the  ends  to  be  joined  should  lie  coated  with  one  heavy 
or  two  light  coats  of  acid-cure  splicing  cement.  With  the  tul>e  and 
patch  property  placed  on  the  mandreLs — tulie  on  the  male  aiul  patcli 
on  the  female — turn  back  the  end  to  be  repaired  ntul  tlie  eiui  to  lie 


I 


GASOLINE  AUTOMOBILES 


times  very  useful,  as  shown  in  Fig.  564.  Here  the  pinched  tube 
and  l)l(iwout  are  indifatwl,  the  results  of  these  on  the  inner  tube 
and  also  their  method  of  reiwir  haviiif;  just  been  described-  These 
troubles  together  with  punctures,  leaky  valves,  and  porous  rubber 
in  the  tubes  about  cover  the  extent  of  iiu)er  tube  troubles.  Because 
of  their  more  complex  construction,  casings  have  more  numerous 
and  more  varied  troubles,  which,  consequently,  are  more  difficult 
to  repair.  Tlie  more  common  casing  troubles  are  blisters,  blowouts, 
rim  cuts,  and  worn  tread,  the  latter  indicating  the  necessity  for 
retreading.  These  will  be  described 
in  order. 

Sand  Blisters.  The  sand  blister 
shown  on  the  side  of  the  tire.  Fig,  5fJ4, 
is  brought  about  by  a  small  hole,  such 
as  an  unfilled  puncture  hole,  in  com- 
bination with  a  portion  of  the  tread 
coming  loose  on  the  easing  near  this 
hole.  Particles  of  sand,  roa<i  dust, 
dirt,  etc.,  enter,  or  are  forced  inf<i, 
this  hole  and  move  along  the  opening 
provided  by  the  loose  tread.  S(H)n 
this  becomes  continuous  and  tlie 
amount  of  dirt  within  the  break  forces 
the  surface  rubber  out  in  the  form  of  a 
round  knob  known  as  a  sand  blister. 
This  is  cured  by  cutting  open  the 
blister  with  a  sharp  kn»fe  on  the  side 
toward  the  rim  and  picking  out  all 
dirt  within.  When  the  rt'cess  is 
thoroughly  cleaned,  the  hole  an<l  the 
radial  hole  in  the  tire  tread  nearb\- 
should  be  filled  with  some  form  of 
self-curing  rubl)er  filler,  a  number  of  kinds  of  which  are  sold.  The 
double  benefit  of  this  is  to  close  the  hole  so  that  the  trouble  is  not 
repeated  and  to  keep  out  moisture  which  would  ultimately  loosen  the 
entire  tread. 

Blowouts.     The  blowout,  which  is  perhaps  the  most  important 
casing  repair,  may  be  made  in  two  ways:   the  inside  metho<l,  in  which 


1 

7t- 

1    { 

f 

-   1 

- 
_ 

* 

Mclhod  n[  Pni 


ISZ 


OASOLINE  AUTOMOBILES 


the  whnle  repair  li*  elTected  on  tbe  inside;  the  combinatton  insule 
ami  outride  mt-t)irNl. 

Itulde  lit}Kiir  MiHi'hU.  Refer  back  to  Kg.  oG4  for  tlie  general 
tire  coD.struction  a.m\  t'l  Fig.  505  fur  this  particular  case,  the  iiiside 
of  the  tire  is  held  open  by  means  of  tire  hook.<)  and  the  inside  fabric 
layers  or  plies  removed  fwr  a  liberal  distance  on  each  side  of  the 
opening.  As  shown  in  Fig,  565,  a  Iraser  amount  of  the  second  layer 
should  be  taken  than  of  the  first,  and  still  less  of  the  third  and  eaoli 
subsequent  one.  On  .'^J-and  4-inch  tires  it  is  not  advisable  to  remove 
more  tlian  two  plies;  on  4j-inch  tires  three,  as  shown;  and  on  the  larger 
sizes  tour  plies.  The  edge  of  each  layer  of  fabric  should  be  beveled 
down  thin,  as  well  as  the  material  directly  around  the  blowout. 


GASOLINE  AUTOMOBILES  695 

Ins^ide  and  Outside  Method,  In  the  inside  and  outside  method, 
the  material  is  removed  from  the  outside,  stepped  down,  and  beveled 
in  the  same  manner  as  for  the  method  just  described.  Fig.  566  shows 
a  tire  with  a  medium  size  blowout,  which  has  been  stepped  down 
for  a  sectionat  repair,  four  plies  having  been  removed.  The  rule  for 
the  number  of  plies  to  remove  is  about  the  same  as  before,  except  that 
in  the  larger  sizes  this  should  depend  more  on  the  nature  of  the  injury. 
It  should  be  noted,  however,  that  in  this  case  the  plies  have  all  been 
removed  right  down  to  and  including  the  bead.  This  is  done  to  give 
the  new  fabric  a  better  hold  and  to  make  a  neater  job  and  one  that 
will  fit  the  rim  better.  Give  the  whole  surface  two  good  coats  of 
vulcanizing  cement,  allowing  it  to  dry  thoroughly. 

Apply  the  same  number  of  plies  of  building  fabric  as  were 
removed,  with  the  addition  of  chafing  strips  of  light-weight  fabric 
at  the  bead.  Over  this  building  fabric  apply  a  thin  sheet  of  cushion 
gum,  slightly  wider  than  the  fabric  breaker  strip;  then  a  thickness 
of  fabrid  breaker  strip  over  this;  and  then  over  this  fabric  another 
sheet  of  gum,  slightly  narrower  than  the  previous  sheet.  All  this, 
however,  should  be  built  up  separately  and  applied  a^  a  unit  and 
not  one  at  a  time,,  as  described.  These  several  plies  should  be  well 
rolled  together  on  the  table.  All  edges  should  be  carefully  beveled  off, 
especially  the  edges  of  the  new  gum  where  it  meets  the  old,  as  it  is 
likely  to  flow  a  little  and  leave  a  thin  overlap  which  will  soon  pick 
loose. 

No  fabric  is  removed  from  the  inside,  but  the  hole  is  cleaned,  its 
edges  beveled,  then  filled  with  tread  gum,  and  the  inside  reinforced 
with  a  small  patch  of  building  fabric;  over  this  lay  two  plies  of 
building  fabric  of  considerable  size.  Now  the  whole  casing  is  placed 
in  a  sectional  mold,  a  surface  plate  applied  to  the  outside,  and  heat 
applied  both  inside  and  outside.  This  will  heat  the  tire  clear  through 
and  make  a  good  thorough  job  of  curing. 

Rim-Cut  Repair.  Partial  Cut.  To  repair  a  partial  rim  cut, 
one  or  two  plies  of  the  old  fabric  are  removed,  unless  it  is  severe, 
when  three  plies  may  be  taken  off.  This  is  removed  right  down 
clean  as  explained  under  Blowout  Repairs,  and  the  cement  and  new 
materials  applied  in  the  same  way,  with  the  omission  of  the  fabric 
breaker  strip.  However,  care  should  be  used  to  carry  all  building 
fabric  layers  not  only  down  around  the  bead  to  the  toe  but  up  on 


This  it)  ii)a<k-  on  tlic  t;il>l<-  iiiui  tlit 
When  compli'tcd,  viiltaiiizc  in  a 
bag  and  lioati  molds  or  ciicllcss  aii 
wrap,  and  viilcanixc  in  hcator  or 
not  vulcanizt-tl,  ami.  with  tiie  ends 
rial  loosened  to  show,  may  Iw  seen  i 
Retreading.  Uctrcailinj;  is  a 
carefully,  ni)t  only  Ix-eaiise  of  tlie 


GASOLINE  AUTOMOBILES 


697 


tihould'be  cleaned  off  right  down  to  the  carcass,  and  the  latter  cleaned 
thoroughly.  As  the  rubber  sticks,  a  rotary  wire  brush  will  be  found 
useful  and  quick.  However,  this  should  be  used  carefully  so  as  not  to 
gouge  the  carcass.  After  buffing,  the  loose  particles  of  rubber  should 
Iw  remo\ed  with  a  whisk  broom  or  dry  piece  of  muslin.  In  this 
cleaning  work  the  carcass  should  be  kept  clean  and  dry.  Apply  two 
foats  of  vulcanizing  cement  and  allow  both  to  drj-;  the  first  should  be 
a  light  coat  to  soak  into  the  surface  fabric;  the  second  should  be  a 
heavy  coat. 

Building  Up  the  Tread.  In  building  up  the  tread,  it  should 
not  be  made  as  heavy  as  the  former  tread,  as  the  old  worn  and 
weakened  carcass  cannot  carry  as  heavy  a  tread  as  when  new. 
Furthermore,  it  takes  longer  to  vulcanize  a  heavy  tread  and  presents 
more  opportunity  for  failure.  In  the  building-up  process,  the  pro- 
portioning of  weiglits  is  important,  and  should  be  taken  from  the  tab- 
ulation below,  which  represents  ^ears  of  experience  in  tire  repairing: 


ir 

Fabric 
<in.) 

Second 

Third 

'ffi 

S' 

h^i/j^ 

ComploM 

3 

2 

31 

•See  Note 

3  plies 

31 

2 

31 

4 

•See  Note 

4  plies 

3 

4 

•See  Note 

4  plies 

41 

4 

5 

4  plies 

41 

5 

5 

o; 

•St*  Note 

.i  plips 

51 

51 

G 

73 

•Sec  Note 

0  plies 

G 

■ll 

G 

'' 

111  uf  i-aK  aftcc  buffiug  anil  Tt 


This  tread  strip  is  built  up  on  the  table  with  exceeding  care, 
all  edges  being  rolled  down  carefully.  When  tlie  strip  has  been 
propure<l  anti  the  carcass  is  remlj'  for  it,  one  end  should  be  centered 
on  the  careass,  and  then  the  balance  of  the  strip  applied  an)un<l  the 
circumference,  being  careful  to  center  it  all  around,  as  the  workman 
in  Fig.  508  is  doing.     After  it  has  been  applieil  all  around,  it  should 


;.\Si»IJXE   AUTOMOBILES 


I  St  <if  kelincr. 


ISv 


11,\ ,  ;i]l  air  pot-kets  opened  with  a  sharp  pointed 
tlic  edges  of  the  plies  rolled  down  with  the 
W'luii  ready,  vulcanize  in  a  kettle,  using  an 
in-  applied  to  a  split  curing-rim,  and  wrapped — 
i)jH-r] — all  around. 

Many  a  casing  which  appears  good  on  the  out- 
i-  iiii>itfe  Ix-cause  of  fabric  breaks  on  the  insido 
■iiii  be  saved,  or  its  life  temporarily  prolonged, 
ly  tlie  application  of  a  reliner.  By  this  is  not 
iH-arjt  the  prepared  canvas  and  fabric  reliner 
\lii(Ii  can  be  put  in  dry.  but  a  regular  built-up 
trip  of  building  fabric,  \Tilcanized  in  place  so  aa 
to  be  an  integral 
part  of  the  tire. 
For  ordinary 
breaks,  use  a 
single  ply  of 
building     fabric 


GASOLINE  AUTOMOBILES  699 

out,  perhaps  he  could  not  do  a  better  thing  than  to  tak^  an  old  tire 
apart  to  see  just  how  it  is  constructed.  This  will  give  a  much  more 
clear  idea  than  any  number  of  diagrams,  sketches,  or  photographs. 

The  tire  repair  man  should  remember,  too,  that  this  is  no  longer 
a  game,  but  that,  bj'  means  of  scientific  apparatus  and  the  appli- 
cation of  correct  principles,  it  has  been  brought  up  to  a  high  state 
of  perfection;  an  expert  can  predict  with  reasonable  accuracy  what 
will  happen  in  such  and  such  a  case,  if  this  and  that  are  not  done. 
In  short,  the  tire-repairing  business  within  the  last  few  years  has 
been  brought  up  to  a  stage  where  it,  or  any  part  of  it,  is  a  dependable 
operation.  The  tire  repair  man  should  handle  all  his  work  from 
this  advanced  point  of  view;  it  will  pay  the  largest  dividends  in 
the  long  run. 

SUMMARY.  OF  INSTRUCTIONS 

Q.    What  are  the  units  comprising  the  final-drive  group? 

A.     Universal  joints;  driving  shaft;  final  gear  reduction;  axle- 
shaft  differential;  axle  enclosure;  torque  rod,  or  tube,  or  substitute 
tor  this:  radius  rod,  or  tube,  or  substitute  for  this;  brakes;  wheels;  and 
_  tires. 

Q.    Why  are  these  called  the  final-^rive  group? 

A.  Becausethey  constitute  the  final  drive  of  the  car,  beyond  the 
power-producing  unit,  the  engine;  the  connecting  and  disconnecting 
unit,  the  clutch;  and  the  speed-changihg  unit,  the  transmission. 

Q.    What  is  the  function  of  the  universal  joint? 

A.  In  the  final-drive  group,  it  is  used  to  transmit  power  at  an 
angle,  as,  from  a  horizontal-transmission  shaft  to  an  inclined-driving 
shaft. 

Q.    How  does  it  do  this? 

A.  The  construction  is  such  that  the  driving  shaft  is  attached 
to  one  set  of  pins,  while  the  driven  shaft  is  attached  to  another,  the. 
axes  of  these  intersecting  in  a  common  point.  As  tlie  driven  shaft  can 
turn  about  its  pins  in  one  plane  and,  with  the  complete  joint,  about  the 
driving  shaft  pins  in  another,  as  well  as  combinations  of  the  two, 
complete  freedom,  or  universal  movement,  is  assured. 

Q.    What  are  the  power  losse£  in  a  universal? 

A.  In  a  wellniesigned  and  fitted  universal  joint,  working  pratv 
tically  at  zero  angle,  there  is  no  loss,  but  as  the  angle  increases,  the  loss 
increases  until  at  about  20  degrees,  it  may  reach  2  or  3  oer  cent. 


n.  1  lie  engine  levei  vanes  lit 
varies  up  and  down  through  a  coi 
rear  end  carries  perhaps  K.5  per  cei 
road  shocks  because  of  this  fact, 
front,  or  engine,  end  as  quiet  and 
These  considerations  necessitate  a  i 
ends,  30  that  one  can  move  free 
distances,  while  the  other  moves 
distances.  In  addition,  the  rear  e 
away,  so  that  freedom  in  a  sidewiw 
way  in  which  these  necessities  can 
universal  joints. 

Q.    What  is  a  slip  joint? 

A.  One  which  will  allow  slidi 
within  the  other.  Thus,  under  cer 
and  fall  of  the  rear  end  may  mean  a 
to  and  from  the  front  portion.     W 

Q.    What  is  the  usual  form  of 

A.  Generally,  this  take^  the 
sqiiared-out  housing,  although  son 
to  give  a  slight  universal  action. 

Q.    What  is  the  modern  form 

A.  A  thin  flexible  disc  of  steel 
with  the  drivinE  shafts  bolted  to  t 


GASOLINE  AUTOMOBILES  701 

Q.    What  is  the  biggest  advantage  of  these  to  the  repair  man? 

A.  They  allow  the  removal  of  a  driving  shaft,  or  a  unit  on  either 
side  of  such  a  joint  much  more  quickly  and  easily,  with  less  work, 
than  any  other  form,  similarly,  in  replacement  after  the  repair  is 
completed.  In  addition,  they  have  no  loose  parts  to  be  lost  or  mis- 
laid with  consequent  trouble  and  delay  of  the  work. 

DRIVING  SHAFTS 

Q.    What  is  the  usual  type  of  driving  shaft? 

A.  The  usual  driving  shaft  is  of  small  diameter  and  solid. 
Cold  rolled  steel  is  used  on  the  lower  priced  cars,  but  forged  steel 
machined  at  the  ends  (at  least)  is  used  on  the  better  cars.  On  many 
of  the  most  expensive  machines,  the  shaft  is  fairly  intricate  in  shape 
and  is  machined  all  over  after  forging,  sometimes  ground  after  har- 
dening. 

Q.    What  would  be  the  advantage  of  a  spring  shaft? 

A.  Being  flexible,  it  would  cushion  the  shocks  so  that  none  of 
these  reached  the  engine.  Such  shocks  as  are  induced  by  jerking 
the  throttle  wide  open,  or  stepping  on  the  accelerator  pedal  suddenly 
or,  on  the  other  hand,  a  sudden  application  of  the  brakes. 

Q.    What  is  its  real  disadvantage? 

A.  Being  small,  the  owner  of  the  car  and  the  driver  would 
always  mistrust  it,  and  would  not  feel  free  to  drive  as  they  would  with 
a  larger  and  more  dependable  shaft. 

Torque  and  Radius  Rods 

Q.    What  is  torque? 

A.  Torque  is  turning  effort,  or  force,  applied  to  rotation,  in  the 
case  of  an  automobile,  to  rotation  of  the  driving  shaft,  and  from  it  to 
the  rear  axle  and  wheels  by  means  of  the  final  reduction  gears. 

Q.    What  is  a  torque  rod? 

A.  A  rod,  bar,  or  tube,  provided  to  take,  not  the  torque,  but  the 
equal  opposite  reaction  from  the  torque  application  to  the  final  drive. 

Q.    What  is  the  manifestation  of  this  torque  reaction? 

A.  A  tendency  of  the  driving  shaft  and  driving  bevel  gear  to 
rotate  up  and  around  the  bevel-driven  gear  in  a  counter-clockwise 
direction. 

Q.    How  does  the  torque  rod  absorb  this?  ^1 

A.     By  extending  this  forward  and  attaching  it  to  a  frame  cross 


A.  In  one  of  three  w 
transmit  it  directly  to  the  fra 
both  torque  and  driving  effor 
member,  then  to  the  main 
which  are  modified  in  attaci 


Q.    Which  is  the  best  f 

A.  The  use  of  radius  r 
stresses  directly  to  the  frame, 
the  most  expensive,  the  lieavii 
parts. 

Q.    Which  is  the  most  s 

A.     The  use  of  the  spring 

also  reduces  tlic  easy-riding  q 

which  should  be  flexible  for  i 

rigid  in  order  to  transmit  torqi 

Q.    Which  is  th?  cheapef 

A.     Undoubtedly  the  use 

it  eliminates  all  ad<!itional  ]>a 

fonn  of  springing  end  in  place  i 

FIN, 

Q.    What  are  the  usual  m 


GASOLINE  AUTOMOBILES  703 

A.  Fqf  pleasure-car  use,  the  spiral  bevel  form,  and  for  motor 
trucks,  the  worm. 

Q.    Why  Is  the  spiral  bevel  popular  on  pleasure  cars? 

A.  Because  of  its  many  advantages.  It  Is  just  us  simple  as  the 
straight  l>evel,  needs  no  additional  parts,  is  more  ({uiet,  perhaps  mora 
efficient,  is  less  likely  to  cut  or  wear,  can  be  removed  as  readily,  and 
has  other  minor  advantages. 

Q.    Why  is  the  worm  popular  for  trucks? 

A.  It  has  all  the  needed  qualities;  it  is  etRcient,  silent,  easy  to 
handle,  and  allows  bigger  gear  reductions  than  any  other  form. 
Furthermore,  various  gear  reductions  are  interchangeable  by  changing 
other  parts,  and  the  worm  lias  other  ad\'antag€s. 

Q.    Why  is  the  worm  not  used  more  on  pleasure  cars? 

A.  Because  it  is  not  so  well  adaptai  ti»  high  speeds  of  50  to  60 
miles  an  hour  and  higher,  which  may  be  demanded,  and  because  the 
large  retiuction  between  engine  and  rear  axle,  which  is  its  biggest 
advantage,  is  not  needed  on  pleasure  cars. 

Q.    What  are  the  three  mostly  used  forms  of  rear  axle? 

A.     The  full  floating,  semi-floating,  and  three-quarter  floating. 

Q.    Which  is  the  best  form? 

A.  From  an  engineering  standpoint,  the  full  floating  is  undoubt- 
edly the  best,  but  it  is  also  the  most  complicated,  with  the  largest 
number  of  parts,  and  the  most  expensi\'e  to  construct. 

Q.    Which  is  the  most  simple  form? 

A.  The  semi-floating  form  is  the  most  simple,  but  it  lacks 
advantages  which  the  majority  of  car  owners  want.  It  is  the  cheapest 
to  make,  but  is  ma*Ie  so  thn>ugh  the  lack  of  these  advantages. 

Q.    Which  is  the  compromise  form? 

A.  The  three-quarter  floating  fonn  seems  to  offer  a  maximum 
number  of  advantages  with  the  minimum  of  disadvantages.  It  has 
practically  alt  the  aiivantjvges  of  the  full  floatiag  with  less  cost.  It 
has  all  the  advantages  which  the  semi-floating  lacks  and  costs  but 
little  more. 

Q.    Which  is  the  most  popular  form? 

A.  The  floating  still  has  the  greatest  num)>er  of  makers,  but  the 
three-quarter  form  is  rapidly  gaining  in  popularity  and,  in  another 
year,  will  displace  the  full  floating  as  the  most  popular,  both  as  to 
the  number  of  makers  and  as  to  the  actual  number  of  cars. 


Q.    What  is  a  differential 

A.     A  inccliaiiioal  (!cvi«T  I 

(lifTcrciit  (listaiut's  wlicn  tiimiii] 

Q.     How  is  this  done? 

A.     By  a>ml>iiiiiti(iiis,  or  u 

one-half  being  fixed  t<»  ench  half 

of  gears  connet'ting  the  two.     .' 

or  stand  still  and  have  their  g< 

transmitte<I  all  to  one  wheel,  hal 

Q.    What  is  the  usual  diffe 

A.     The  usual  .iifferential 

spur  gears,  the  bevel  fonn  being 

Q.    What  is  undesirable  in 

A.     Present  tiiffercntials  hi 

for  resistanee  not  distanct;.     Thi 

want  to  slip,  to  slip  on  icy  i>la('cs 

the  diFercntial  making  a  bail  niai 

Q.    If  the  differential  work 

A.     In  such  a  cas<',  since  tt 

enci;  in  distance,  and  tlicre  was 

place,  the  [Kiwer  wonld  he  tran 

One  would  slip,  hnt  tt)c  iitlicr  m 

the  iM>wer  to  pull  tlic  car  olF  the 


GASOLINE  AUTOMOBILES  705 

present  differciitinls  has  never  been  explained,  but  can  be  readily 
proved  by  the  simple  process  of  building  a  car  without  a  difTerentiaL 

Q.    What  forms  of  bearings  are  used  in  rear  axles? 

A.  Ail  the  different  kinds  of  bearings  are  used  in  rear  axles: 
plain  bull,  plain  straight  solid  mller,  striiight  flexible  roller,  tapered 
roller,  a  few  plain  bnmze  bearings,  ball-tlirust  forms,  and  others. 

Q.    Which  form  is  most  popular? 

A,  There  is  little  choice  between  the  two  forms  of  roller  and  the 
ball  bearing.  In  fact,  the  majority  of  axles  use  several  <litferent  forms 
of  bearings;  so  it  is  difficult  to  compare  the  work  of  the  various  bearing 
tj-pes. 

Q.     How  can  a  broken  spring  clip  be  repaired? 

A,  A  good  substitute  for  a  spring  clip  can  be  made  from  two 
flat  plates  and  four  bolts  to  reach  from  one  plate  to  the  other.  The 
purpose  of  the  spring  chp  is  to  hold  the  spring  to  the  axle;  this  combi- 
nation will  do  the  same  thing. 

Q.     How  would  you  line  up  a  rear  axle? 

A,  With  a  try-square  and  plumb  bobf  workiiip  downward  from 
the  main  frame,  determine  the  distance  from  the  rear  end  of  the  frame 
to  the  back  side  of  the  rear  axle,  on  each  side  i>f  the  car.  Jf  the  two 
do  not  agree  exactly,  the  axle  is  out  of  square  by  the  difference,  or  by 
half  this  difference  on  each  side.  I>o(iseu  the  spring  holts,  set  the  axle 
correctly,  tighten  the  Ixtlts,  and  check  up  the  measurements  again. 

BRAKES 

Q.    What  are  tlie  two  general  t^es  of  brakes? 

A.  The  eontracting-band,  which  is  an  external  brake,  and  the 
internal-expanding  shoe. 

Q.     How  are  these  used? 

A.  There  is  no  set  rule;  some  designers  use  only  the  internal- 
expanding  form,  claiming  this  is  more  powerful  and  dependable; 
others  use  only  the  band,  claiming  this  Is  cheaix'r  to  make  and  repair 
and  just  as  good;  still  others  take  no  side  but  use  both  forms. 

Q.    Has  there  ever  been  any  agreement  in  relation  to  brakes? 

*  A.     I'p  to  about  a  year  ago,  it  was  general  practice  to  use  the 

internal-expanding  shoe  brake  for  the  emergency,  nr  hand,  brake. 

This  was  the  case  whether  the  band  form  was  usei!  for  the  fnot,  or 

running  brake,  iir  another  expan<liiig  sIkk-. 


A.  Except  f«>r  the  teiiitei 
been  l<K-ate<l  as  mudi  as  possthlt 
that  this  gave  the  m(jst  direit 
braking  forte. 

Q.     How  are  brakes  arrani 

A.  When  bwth  brakes  an- 
sharply  dividefi  into  two  camps, 
as  a  band  form  on  the  outside 
a  smaller  lighter  drum,  a  more  c 
expensive  because  the  dnim  is 
brakes  side  by  side,  making  both 
inside  a  wide  <lruni,  claiming  th 
and  that  the  brakes  are  better  pr 
l>eeause  entirely  enclosed,  and  tl 
attention. 

Q.    \\'hat  is  the  electric  bra 

A.  A  new  de\ice  which  su 
motor  for  hand  or  foot  applicatii 
action  by  a  finger  lever  on  the  s 
through  suitable  resistanir,  betwe 
the  motor  rotates  a  cable  is  wount 

Q.    Is  this  a  powerful  form? 

A.  Not  only  very  powerful 
care  must  Iw  o-uvl  ii.  ...."i.:---  ^^ 


GASOLINE  AUTOMOBILES  707 

ward  again;  this  action  soes  not  release  the  brakes  but  does  apply 
more  force,  that  is,  it  can  be  worked  continuously  until  sufficient 
power  is  applied  to  stop  the  vehicle,  a  peculiarity  of  this  particular 
form. 

Q.    What  is  the  vacuum  brake? 

A.  A  new  form  which  utilizes  the  suction  of  the  engine  to  create 
a  vacuum  in  a  special  braking  cylinder,  the  movement  of  a  piston  in 
which  applies  the  brake.  The  amount  of  action  depends  on  the 
amount  of  suction,  that  is,  regulated  by  the  amount  the  valve  is 
opened,  and  this  is  dependent  upon  the  pressure  applied  to  the  finger 
lever  or  toe  button,  whichever  is  used. 

WHEELS    ' 

Q.    What  are  the  usual  forms  of  pleasure-car  wheels? 

A.  The  plain  wood  form  and  the  wire  wheel  comprise  99  per 
cent  of  all  pleasure-car  wheels;  the  wood  forms  about  three-quarters 
and  the  wire  about  one-quarter  of  the  total. 

Q.    What  are  the  tendencies  in  wheel  sizes? 

A.  On  small  cars  the  tendency  is  toward  larger  and  larger  sizes, 
but  on  the  larger  heavier  cars  the  tendency  is  away  from  the  very  large 
sizes  of  a  few  years  ago.  The  latter  tendency  has  been  brought  about 
by  the  standardization  of  tire  sizes,  and  the  elimination  of  38s,  40s, 
and  larger  sizes  formerly  made. 

Q.    What  are  the  different  forms  of  wire  wheels? 

A.  The  double-spoke  form,  which  is  lacking  in  lateral  strength; 
the  triple-spoke;  and  the  quadruple-spoke.  The  two  latter  make  up 
in  strength  what  the  former  double-spoke  form  lacked.  Except  for 
number  of  spokes,  these  do  not  look  any  different  to  the  casual 
observer. 

Q.    What  is  the  sheet-steel  wheel? 

A.  A  form  in  which  the  whole  wheel  construction  consists  of  a 
pair  of  sheet-steel  members.  These  are  given  a  slight  taper,  some- 
times have  holes  through  them  for  ventilation  and  to  make  them 
lighter,  and  frequently  are  painted  to  resemble  wood-spoke  wheels. 
The  steel  sheets  are  made  thin  enough  to  be  flexible. 

Q.    What  is  the  pressed-steel  wheel? 

A.  A  newer  form  in  which  a  simulation  of  one-half  the  entire 
wheel  spokes,  hub  and  all,  is  pressed  out  of  thin  sheet  steel,  and  a  pair 


yf.     nnKn  H  the  most  po 

A.     The  wood  form  is  stii 

vantages  for  heavy  truck  use, 

Q.    What  are  the  advanta 

A.     Greater  strength,  pan 

ventilation  am)  removal  of  heat 

for  the  tire  so  that  it  holds  its  sh 


Q.    What  are  the  general  d 

A.     Pneumatic,  cushion,  an 

Q.    What  is  the  principle  o 

A.     The  pneumatic  tire  has 

full  of  air,  the  tire  gaining  its  res 

is  HO  wnstrurted  as  to  have  a  c 

span!  sf>  that  it  gives  a  cushion  ef 

solid  mas-t  o{  riibI»«T,  its  only  give  i 

Q.    Is  there  a  distinct  tield  1 

A,     Yes.     Pneumatics  are  i 

ligliter  trucks  or  delivery  wagon; 

slow-spec<l  electric  pleasure  cars  a 

UHod  only  on  the  heavy  trucks. 

Q.    What  is  the  big  disadvai 

A.      Its  liahilitv  to  nnncfiir» 


OASOUNK  AUTOMOBILES  700 

Q.    Describe  the  clincher  type? 

A.  This  is  made  with  a  bead  or  hard  portion  at  the  base,  which 
forms  a  projection  around  which  the  clincher  rim  fits.  The  rim  has 
tlie  shape  of  a  flattened  U  with  the  en<is  ciirlcti  in,  and  the  bends  on 
tlie  tire  fit  into  these  curle<I  ends  or  chnches. 

Q.    What  is  the  advantage  of  this? 

A.  The  clinclitT  form  is  held  firmly  on  the  rim,  while  the  stiffness 
of  the  bead  contributes  more  rigidity  of  form  and  permanence  of 
shape  to  the  whole  tire. 

Q.    Describe  the  straight-side  form. 

A.  This  type  of  tire  has  no  bead,  the  fabric  forming  the  side 
walls  being  carried  straight  down  to  form  the  base  without  additional 
thickness  of  material. 

Q.    What  are  the  advantages  of  this? 

A.  Its  simplicity  and  lighter  weight,  with  greater  air  space  are 
the  advantages  of  the  straight-side  form.  In  addition,  in  the  newly 
standardized  rim  forms,  the  form  of  rim  adapted  to  the  straight-side 
tire  is  more  sim[>le,  lighter  in  weight,  and  lower  in  cost  than  any  other. 
It  has  been  found  by  experience  that  the  holding  power  of  the  beads 
was  unnecessary  as  the  inflated  tire  could  not  come  off  the  wheel 
whether  it  had  a  bead  or  not,  since  its  diameter  at  the  base  could  not 
be  increased  in  any  possible  way  sufficiently-  to  pass  over  the  larger 
size  rim. 

Q.    What  is  an  oversize  tire? 

A,  In  the  stnndanlization  of  tirci  and  rims,  for  each  even  tire 
size,  which  is  called  a  standard,  there  is  an  oversize  made  which  will  tit 
on  the  same  rim  without  any  other  clianftes. 

Q.    What  is  the  difference  between  standard  and  oversize  tires? 

A.  All  standard  tires  are  made  in  even  inches  of  outside  diam- 
eter, and  all  oversize  tires  are  ma<le  in  <Mld  inches  of  outside  diameter, 
S(»  that  the  rule  for  oversizes  is  this:  An  oversize  is  one  inch  larger  in 
diameter  and  J  inch  larger  in  cross-section,  that  is,  the  Font  size 
is  3()  by  .'ij.  the  oversize  for  this,  according  to  the  rule,  is  31  by  4;  an 
tt\-erage  large  car  size  is  -Mi  by  4^,  the  oversize  for  this  is  37  by  5. 

Rlm> 
Q.    What  are  the  general  different  rim  forms? 

A.     lliniH  are  generally  divided  into  these  forms;  plain,  which  Is 


uMi  Lfc  ajijjiieu  easily.  1  ne  aem 
in  combination  with  the  others,  t 
of  the  wheel  by  which  the  entire 
trouble,  and  then  are  replaced  I 
beencarried  for  this  form. 

Q.    What  are  the  advantage 

A.     All  roadside  work  is 

blowout  occurs,  the  driver  simpl 

and  rim,  and  puts  on  the  square  ti 

lets  down  his  car  by  means  of  tht 

damaged  tire,  is  carried  at  the  reai 

in  the  convenience  and  comfort  ( 

station  for  that  purpose.    It  savt 

when  these  are  of  the  greatest  va 

able  rims,  supplied  on  the  car  bj' 

operated  with  all  these  convenient 

Q.    How  are  demountable 

A.     Nearly  all  demountable^ 

separate  bolts  to  press  these  into  p 

the  bolt  and  wedge  are  combined. 

TIRE  I 
Q.    What  is  vulcanization? 

A.     Vulcanization  is  the  curi 


GASOLINE  AUTOMOBILES  711 

ual  tire-curing  mold  the  central  space  for  the  tire  is  surrounded  by 
etal,  with  &  hollow  annular  space  outside  of  this  into  which  the 
iam,  which  is  generally  used,  is  introduced.  The  heat  from  this 
mm  penetrates  the  metal  inside  and  vulcanizes  the  tire. 

Q.    Are  all  vulcanizers  operated  by  steam? 

A.  Practically  all  the  larger  ones  are,  but  many  of  the  smaller 
rms  of  the  portable  type  bum  gasoline  in  the  heating  space,  others 
e  electric  resistance  coils. 

Q.    What  is  the  advantage  to  the  private  owner  of  a  vulcanlzer? 

A.  When  a  tire  is  cut  badly,  he  can  apply  raw  rubber  as  a  patch 
repair,  and  then  vulcanize  this  for  the  double  purpose  of  curing 
.d  of  uniting  it  with  the  older  part  of  the  tire.  In  this  way,  tire  life 
much  prolonged  at  little  expense. 

Q.    Is  vulcanization  profitable  as  a  business  for  a  repair  shop? 

A.  It  is  said  to  be  highly  profitable,  after  suitable  equipment 
a  been  purchased  and  a  trade  built  up.  It  is  said  to  be  a  more 
•ady  and  stable  business  than  any  other,  for,  as  soon  as  an  owner  has 
en  convinced  of  the  value  of  vulcanization  of  tubes  and  casings,  he 
11  bring  in  all  his  tire  repairs. 

Q.    What  U  a  sand  blister? 

A.  A  small  opening  in  a  casing,  into  which  sand  has  entered  and 
ntinues  to  enter  until  the  outer  surface  is  swelled  up  just  like  a 
ister.    If  neglected,  this  will  ruin  the  casing. 

Q.    How  should  a  sand  blister  be  cared  for? 

A.  By  the  immediate  removal  of  the  sand  and  the  cleaning  of 
e  cavity,  after  which  it  should  be  filled  with  a  tire-repairing  cement 
tire-filling  compound.  The  sand  can  be  removed  by  cutting  a  small 
>le  in  the  underside  of  the  blister  with  a  sharp  penknife. 


INDEX 


INDEX 


Adjustable  crankshafi   llangcH.     !<:; 
Adjutttliig  annular  bearings....  421 

Adjusting  clutch   pedals :17S 

Adjusting  fans    302 

Adjusting  pumps    303 

Adjusting  spring    hangers 544 

Adjusting  tension  ot  valves...  257 
Adjustment  of  air  and  gasoline 

supply    106 

Adjusinieni    ot    connecting-rod 

bparlngs  6!< 

Adjustment  of  nozzle I!)S 

Air  i^oollng  300 

air  Ja<^ketB    301 

blowers  and  fans 301 

flanges,  or  fins 300 

Internal  cooling  and  scaveng- 
ing     301 

Air  Jackets   301 

Alignment  of  front  wheels r>03 

Antl-freezIng  solutions 2^9 

Automatic  gear-cutting  machine  423 

Auxiliary  air  valve 107 

Axle  bearings    501 

B 

nail  and  Ball  carburetor 151 

tlall   tiearlngs    334,502 

Bearings   Tfi.  330 

ball  bearings    334 

bearing  wear 77 

combined    radial    and    i  bi  nsi 

bearings  337 

crankshaft    jioundlng   7S 

handy   wrench    80 

holding  for  bearings  caps...  70 

plain  bearings   331 

roller   bearings    332 

test  tor  tightness 78 

Becker  gear-cutting  machine. . .  424 

Bending  oil  pipes .32!i 

Bennett    carburelor    185 

Bent  needle-valve  stem ....  I9G 


t>Sgl> 

Bevel  gears    42K 

Bevel  type  of  friction  disc 402 

BUgram  gear-ulanlng  niacbine.   4ZT 

Blowers  and   fans 301 

Blowouts  in  tire  repair 6»3 

Brake  adjustments  '. . . .  613 

Brake  lubrication   613 

Brakes    604 

brake  adjustments    613 

brake  lubrication   613 

brake  troubles  and   repairs..   617 

elassiflcat  ion     605 

double  brake  drum  for  safely  610 

electric   613 

external-contracting  605 

function    604 

hydraulic    614 

Internal-expanding    60G 

methods  ot  brake  operation.  GtO 
recent  developments   613 

Brown  and  Sbarpe  gear-cutting 
machine    423 

Browne.Branford    carburetor.. .   132 

Browne  carburetor — one  adjust- 
ment       130 

Bushing  removers  56 

C 

('able  iind  rope  drives 402 

Cadillac  carburelor    1T4 

Cams 232 

Can!  Ilever    ; , . . .  534 

Carburetor    9!) 

rlasBlflcatlon    101 

effect  ot  heavier  fuels W 

floats  lOS 

function  of  ihe  carburelor..  9ti 

needle  valves  104 

throttle  valves  103 

Carburetor  adjustment,  general  19T 

Carburetor  and  carburetlon, . .  R9 
Carburetor   operation    and    ad- 

lustm«DtB    112 


Hiir  oiiTallon  Hiid 
ifiiicnia  ii'Oinliiiiedi 
iiiKl   BhII  ciirlJiircU.r 


13Q 


i-iniillai*  railiiirpior lU 

larlmreiorsi  on  Kord  i^ars 122 

Curtpr  car  In  I  ret  HI'   .  .    ,,,....  170 

lli'iiiif  bSk  gpneratiir 193 

KilwardK  ciirhnrplnr- 137 

forelRTi   kerosfiii'  ciirljiiii'iors  181 

"H  &  S'  diiiilpx  carliuielor.  189 

Hoilvy    carhiirplni-    ,         ,  ,12i>.  180 

.loliiisoD  .iii-l'iiieUiT 167 


I'Brburetor  Iroiiblps  and  reinp- 
dies   (conlinuedl 
emalleBt  detail   iintxtrlani. . .  2 
throttle  loose  on  shaft 1 

Carter  carburetor  1 

t-steel  wheels 8 

Chain  drive  for  camshatts. .. .  2 

Changing  tires  G 

Interchangeable     Continental 

tires  fl 

Interchangeable     .M  i  c  hcltn 


Tfrf 


possible   tire   cbBngeE.  , .  .. ,  .  G 
aiieed  changes  due  to  changed 


CharacterisllcE  o(  good  oils. .- .  3 
Characlerlsllce   of   pislon   rings 

chassla  group    5 

characteristics  of  parts 5 

frames  5 

shoclt  absorbers 5 

springs    S 

Checking  up  cylinder  bore... 


INDEX 


Pa««' 
Commercial-car     wheels     (con- 
tinued) 
modern    status    of    spring 

wheel    642 

requisites    636 

wheel  troubles  and  repairs..  643 

wood    637 

Commercial  vehicles,  construc- 
tion of  frames 523 

Composition    and    manufacture 

of  tires  673 

Cone  clutch 352 

Connecting-rod  bearings  63 

Connecting-rod  troubles  and  re- 
pairs         65 

Connecting  rods    61 

Contraoting-band  clutch   364 

Cooling  systems 286 

air  cooling    300 

cooling   troubles  and  adjust- 
ments      302 

water   cooling    286 

Cooling    troubles    and    adjust- 
ments      302 

Cork  inserts   375 

Oankcase    arms    and    engine 

supports   87 

Crankcase  construction  84 

Crankcase  materials    87 

Crankcase  oil   329 

Crankcase   troubles  and   reme- 
dies         88 

Crankcases    84 

Crankshaft  bearings 75 

(Crankshaft  and  bearing  troubles 

and  remedies   76 

Crankshaft  and  connecting-rcd 

bearing   shims 75 

Crankshaft  lapping 83 

Crankshafts  72 

Curing  excessive  lubrication..     60 

Curing  noisy   tappet 252 

(^ut-outs    286 

Cutting  valve-key  slots 258 

Cycles  of  engine  operation 11 

Cylinder   and   crankshaft    sub- 
group    22 


rage 
Cylinder    forms    and    construc- 
tion      22 

Cylinder  heads    39 

Cylinder   multiplication    12 

Cylinder  repairs   31 

.    cylinder   heads    39 

grinding  out  cylinder  bore..  41 
locating  noises  by  means  of 

stethoscope 37 

making  gaskets  38 

methods  of  cylinder  lapping.  41 

removal  of  carbon 31 

repairing  cracked  water  jack- 
ets      43 

replacing  pistons  in  cylinders  46 

simple  dead  center  indicator  42 

welding  breaks  In  cylinders.  43 

working  in  valve  cages 46 

D 

Demountable  rims    660 

Deposits  of  carbon  in  cydinder     15 

Deppfi  gas  generator 192 

Disc  clutch   356 

Double  brake  drum 610 

Double  carburetors    for    multi- 
cylinder  motors Ill 

Double-nozzle  type  109 

Dragging  brakes  617 

Driving  reaction   579 

Dummy  brake  drum 618 

E 

Edwards  .carburetor 137 

Electric  brakes    613 

Electric  drive    404,  489 

Electric  transmissions    405 

Electrically  operated  gears 393 

Eliminating  noises  in  gasoline- 
car  brakes 620 

Elliott  type  of  front  axle 492 

Engine   group    3 

carburetion  sub-group  3 

cooling  system 5 

cylinder  and  crankshaft  sub- 
group         3 


exliauBt  system   5 

flj-whpcl 7 

ignlilou  syBiem   

iulcl  nuct  elhausi   valKs... 

llgbttng  system  

lubrlcailoD  sjatem 

siarilDg  system 

Engine  Iroubies  and  re^Mlrs. . 

Exhaust  systeoi XT!I 

ExbBUSl-Tslve  setliiie  .-  . .  U9 
Expanding-baDd,  or  rilis  ilUrh  SE& 
External  lubricetion IIS 


Failure  of  clutch  lo  lokp  bold.  3 
Failure  or  tuel  lo  flaw  fii^m  full 

grSTlTy  lank  ...  I 

Failure  lo  slarl  ensine.        .,    . 

Fans . .  3 

FpIIowk   gear   aha(iiT 4 

Fiprce  dutch 3 


Frame*    

daesca  of  trainee B1 

afflirart   mi    iiprlii«» 

(ntnut  imuhloA  and  ixnnlrS' 

sentml  clunclitisiLcB  

prv«M>d-«Ji-«l   rraiova 

rigid  (raaieB , .  (I 

vub-lrames 

twudvBL-y  In  dexicn 

(jpHK  of  fraiiw* tl 

FrirUotialpIiiiesbockabMrtiQr..  fii 

FtMR  drirw   « 

Ftvtmg   irrlcl    plus  and   biuh- 

ttigs j 

Krletton    | 

FroBt  axles  || 

axle  bnarlBpi B 

luaiMiatB    ,  (j 

iTtiahlc*  niMl  rxpoirs 6 

iyp»» t 

Kront-nkeel  drlte...... ^I 

tmnnH   .,,-...., 4J 

dlHoulllcs  of  tnttianilsaloii..  41 

rrti-llnn.dllai>  tnnamtHbm  M 


liS'DEX 


l»age 
H 

"H  &  N"  duplex  carburetor 189 

Handling   clutch    springs 373 

Handling  shaft  in  machines...  81 

Handy  spring  tool 417 

Heating    410 

Heating  charge   209 

Helical  and  herringbone  gears.  429 

Hoists  and  cranes 18 

Holding  crankshaft    81 

Holding     valve     springs     com- 
pressed     * . . .  25G 

Holley    carburetors 125,  180 

Hydraulic  brakes    614 

Hydraulic  gear    403 

I 

Individual  clutch 395 

Individual  pump  pressure  feed- 
ing     317 

Inlet  manifold  design  and  con- 
struction       205 

Inner  tube  repairs 689 

inserting  new  sections 691 

large  patches   689 

simple  patches 689 

Inside'  casing  forms 683 

Interchangeable    Continental 

tires   652 

Interchangeable   Michelin   tires  651 

interlocking  devices 391 

Internal    cooling   and   scaveng- 
ing     301 

Internal-expanding  brakes 606 

Internal-gear  drive  for  trucks.  585 

J 

Jacking-up  troubles   594 

Johnson  carburetor   1 67 

K 

Kingston   carburetors    127 

Knight    sleeve   valves 272 

Knocking  in  engine 15 

L 

T^rge  patches  in  inner  tube  re- 
pairs       689 


Page 
I^rge  patches  in  inner  tube  re- 
pairs (continued) 

cleaning  hole   681» 

preparing  patch  690 

vulcanizing  patch   690 

layouts  of  equipment  for  tire 

repairs    685 

Leaks  in  gasoline  line 205 

Lemoine  type  of  front  axle 494 

Ix)cating  rear-axle  trouble 602 

Lock  on  fuel  line 219 

I^nguemare  carburetor    139 

I^st  motion  and  backlash 469 

Lost  motion  in  wheel 469 

Lubricating        multiple-disc 

clutches    379 

Lubricating  transmission  gears  420 

Lubrication  of  other  parts 321 

Lubrication  troubles  and  reme- 
dies      325 

bending  oil  pipes 329 

care    of    lubricant     in     cold 

weather    325 

mammoth  grease  gun 325 

oil  filtering  outfit 328 

oil  settling  tanks 328 

oil  tank  and  outfit  for  testing 
bearings   *  326 

M 

Machining  crankcases  89 

Magnetic   clutch    364 

Making  gaskets  38 

Mammoth  grease  gun 325 

Mandrel  for  turning  pins 57 

Marvel  carburetor 157 

Master  carburetor    134 

Material  for  crankshafts 72 

.Mending  breaks 8$ 

Misfiring,  causes  of 203 

Missing  of  explosions 15 

Mixing  gas-engine  cylinder  oil 

with  fuel    330 

Modem  selective  types  of  slid- 
ing gear  382 

Modern  tendencies  in  design..     85 


splHsIi   lubrii.-ariun 

MouDiliif!  iiiaron  on  jarh^- 

.Muffler 

Muffler  [ruNblvs  .  .     , 

Miiltiiili^disc  oluKh-s  failing  ■, 

buld   

.MiiItiiiIt^no2;!l>-  ii.t|>iir>-'(.r^ 


Nolfiy  I 


"il    nilciiiiK    oiirn' 

OtiK    HIJll     KVttHI-H. 

Ciit  MciiliiiK  riink^. 


I'age 


Radiators  and   piping 289 

Railway  car  Deeds 39.", 

Rayfleld  carburetor   147 

Rear-axle  boualngs   uS9 

Rear-axle  lubrication   594 

Rear  asles    ">6!l.  "iST 

assembling    599 

dlaasaembllng  rear  consinic- 

-  tlon    698 

transQilssioo  5G9 

irrmlilfi!   iind   repairs 594 

truss  rods   597 

tyijea  of  rear  axlea 581 

Rear-end  changes  In  framea...  523 

rtear-wheel  bearings    593 

Renioval  o[  carbon 31 

Removal    and    replacement    of 

pistons    53 

Removing   valve    252 

Removing   valve   spring '. .  253 

Repairing  cracked  waier  Jackets  43 
Repairing    poppet    valves    and 

valve  parts  2ri2 

Repairs,  engine  IG 

Replacements  302 

Replacing  clinch  leathera 371 

Replacing  pistons  In  cylinders  46 

K^-iTv-.   i;iiil(s   217 

Retreading  In  tire  repair 696 

Retreading  vnlcanizers  684 

Reversed  Elliott  type  of  (ronl 

axle. 492 

Rigid    frame 513 

RInia   654 

clincher    654 

demountable  (160 

kinds  654 

other  removable  forms (171 

Perlman  rim  patents 668 

plain    654 

quick-detachable   Gu4 

standard  sizes  of 669 

Riveting  frames   527 

Roller  bearings    332,602 


Sagging  of  frames >• 

Sand  blisters  in  tire  repairs...  6 

Saving  balls   4 

Scbebler  carburetors  I 

Selective  type  of  sliding  gear.  3 

Senil-elipiic   sjirings 5 

Semi-reversible  gfar    4 

Senrab   tarbiirctor    1 

Shackles  and  spring  boms  tor 

springs   1 

Sheet-steel  wheels   6 

Shock  absorbers  5 

coll  springs 5 

friction  a  1-plate  type  5 

fund  Ion    5 

general  classes  of  absorbers  a 

hydraulic  suspensions  5 

overload  springs  b 

Side-wall  vnlcanlzer 6 

Simple  (Ire  patches 6 

Single-punip   pressure    feeding.  3 

Sliding  gears    3 

Slip  Joints  6 

Slipping  clutch    3 

Spindle  troubles  and  repairs. ,  5 

Spiral  bevels    t 

Spiral  gears 4 

Splash   lubrication    3 

Spring    construction    and    ma- 
terials    6 

Spring  lubrication 5 

Spring  troubles  and  remedies.  5 

Springs r. 

Spur  and  bevel  type  of  steerlnfc 

gear  4 

Spur  gears    4 

Siiiiidard  filzps  ofilresandrlms  6 
Steering-gear  assembly  (roubles 

and  repairs  4 

Steering  gears 330,  4 

Steering  group 

Steering  rod,  or  drag  link i 

Steering  levers  In  front  of  axle  4 

Steering  wheels  4 

Stewart  carburetor 1 


Bunaerman  ufpiy  rarburetor. . 


Tables  of  valve  settlnsa 23) 

Taking  out  a  valve 261 

Tank  placing  211 

Testing  oils  for  acid,  etc 323 

Testing  alze  at  new  piston 59 

Tbree-quarter  elliptic  springs.  332 

Three-quarter  floating  axle 5SS 

Throttle  loose  on  shaFt IH 

Throttle  and  spark  levers 471 

Throttle   valves   103 

Throwing   in   clutch 379 

Timing  Knight   motor 276 

Tire  repairs 677 

inner  tube  repairs 68S 

Inside    casing   forms 6S3 

layotits  ot  equipment 6Sn 

materials  GS9 

outer  shoe,  or  casing  repairs  6A2 

retreading  vulcanizers    6R4 

side-wall  vulcanlier  6S3 

small  tool  equipment GST 

types  or  vulcanizing  oiilflts..  679 

Tire  valves  675 

Tires   645 

Torque  bar  and  lis  function...  577 

Tracing  a  ring  knock 76 


Washing  

Water  cooling    

anti-freezing  solullons  

circulation  

radiators  and  piping 

Water-Jackel  Jng    106 

built-on  jackets    

Integra.!  Jackets 

welded  applied  jackets 

Webber  aulomatlc  carburetor.  . 
Welding  breaks  In  cylinders.  . . 

Welding  shafla  and  cases 

Wheel  pullers   

Wheel  sizes    

Wheel  troubles  and  repairs,.. 

Wheels   

Whiton  gear-rutUng  machlnp,. 
Wire  wheels  


Wobbling  wheels    507 

Wood  frames   515 

Wood   wheels    624,637 

Working  In  bearings 416 

Working  In  valve  cages 46 

Workstand  equipment  595 

Worm-gear  types    455 

Worm  gears  .' 432 

Z 

Zenith  carburetors   117 

adiustmenta  117 

changing  the  compenHalor. . .  118 

changing  the  main  Jet IIS 

duplex   model  adjustments,.  120 
horizontal     type    of  adjust- 
ments and   changes 119 

slow-speed  adjustmeni    11!) 

lo  replace  main  Jet IIR 


NOV  1      1918 


3  9016  02111    1862