(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "Automobile Engineering"

This is a digital copy of a book that was preserved for generations on library shelves before it was carefully scanned by Google as part of a project 
to make the world's books discoverable online. 

It has survived long enough for the copyright to expire and the book to enter the public domain. A public domain book is one that was never subject 
to copyright or whose legal copyright term has expired. Whether a book is in the public domain may vary country to country. Public domain books 
are our gateways to the past, representing a wealth of history, culture and knowledge that's often difficult to discover. 

Marks, notations and other marginalia present in the original volume will appear in this file - a reminder of this book's long journey from the 
publisher to a library and finally to you. 

Usage guidelines 

Google is proud to partner with libraries to digitize public domain materials and make them widely accessible. Public domain books belong to the 
public and we are merely their custodians. Nevertheless, this work is expensive, so in order to keep providing this resource, we have taken steps to 
prevent abuse by commercial parties, including placing technical restrictions on automated querying. 

We also ask that you: 

+ Make non- commercial use of the files We designed Google Book Search for use by individuals, and we request that you use these files for 
personal, non-commercial purposes. 

+ Refrain from automated querying Do not send automated queries of any sort to Google's system: If you are conducting research on machine 
translation, optical character recognition or other areas where access to a large amount of text is helpful, please contact us. We encourage the 
use of public domain materials for these purposes and may be able to help. 

+ Maintain attribution The Google "watermark" you see on each file is essential for informing people about this project and helping them find 
additional materials through Google Book Search. Please do not remove it. 

+ Keep it legal Whatever your use, remember that you are responsible for ensuring that what you are doing is legal. Do not assume that just 
because we believe a book is in the public domain for users in the United States, that the work is also in the public domain for users in other 
countries. Whether a book is still in copyright varies from country to country, and we can't offer guidance on whether any specific use of 
any specific book is allowed. Please do not assume that a book's appearance in Google Book Search means it can be used in any manner 
anywhere in the world. Copyright infringement liability can be quite severe. 

About Google Book Search 

Google's mission is to organize the world's information and to make it universally accessible and useful. Google Book Search helps readers 
discover the world's books while helping authors and publishers reach new audiences. You can search through the full text of this book on the web 

at http : //books . qooqle . com/| 



Digitized by VjOOQIC 



Automobile 



Gasoline 



Commercial 



Digitized by VjOOQIC 



Digitized by VjOOQIC 



Digitized by VjOOQIC 



Digitized by VjOOQIC 



I 






2 « 

Si 

3* 



Digitized by LjOOQ IC 



1 



Automobile 
Engineering 

A General Reference Work 

FOR REPAIR MEN, CHAUFFEURS, AND OWNERS; COVERING THE CONSTRUCTION, 

CARE, AND REPAIR OF PLEASURE CARS, COMMERCIAL CARS, AND 

MOTORCYCLES, WITH ESPECIAL ATTENTION TO IGNITION, 

STARTING, AND LIGHTING SYSTEMS, GARAGE DESIGN 

AND EQUIPMENT, WELDING, AND OTHER 

REPAIR METHODS 



Prepared by a Staff oj 

AUTOMOBILE EXPERTS, CONSULTING ENGINEERS, AND DESIGNERS OF THE 
HIGHEST PROFESSIONAL STANDING 



Illustrated with over Fifteen Hundred Engravings 



SIX VQLUMES 



AMERICAN TECHNICAL SOCIETY 

CHICAGO 

1920 



Digitized by VjOOQIC 



Copyright, 1909, 1910, 1912, 1915, 1916, 1917, 1918, 1919, 1920 

BY 

AMERICAN TECHNICAL SOCIETY 



Copyrighted -In Great Britain 
AU Rights Reserved 



Digitized by VjOOQIC 



24*982 '^ (olUHLI 

MAY -4 1921 6 

Authors and Collaborators 



CHARLES B. HAYWARD 

President and General Manager, The Stirling Press, New York City 

Member, Society of Automobile Engineers 

Member, The Aeronautical Society 

Formerly Secretary, Society of Automobile Engineers 

Formerly Engineering Editor, The Automobile 



C. T. ZIEGLER 

Automobile Engineer 

With Inter-State Motor Company, Muncie, Indiana 

Formerly Manager, The Ziegler Company, Chicago 



MORRIS A. HALL 

Editor, Automotive Engineering 

Formerly Managing Editor Motor Life, Editor The Commercial Vehicle, etc. 
• Author of "What Every Automobile Owner Should Know" 

Member, Society of Automobile Engineers » 

Member, American Society of Mechanical Engineers 



DARWIN S. HATCH, B.S. 

Editor, Motor Age, Chicago 
Formerly Managing Editor, The Light Car 
Member, Society of Automobile Engineers 
American Automobile Association 



GLENN M. HOBBS, Ph.D. 

Secretary and Educational Director, American School of Correspondence 
Formerly Instructor in Physics, The University of Chicago 
American Physical Society 



HERBERT L. CONNELL, B.S.E. 

-HCate Lecturer, Automobile Division, Milwaukee Central Continuation School 
Editorial Representative, Commercial Car Journal and Automobile Trade Journal 
Member, Society of Automobile Engineers 
Member, Standards Committee of S. A. E. 
Formerly Technical Editor, The Light Car 



Digitized by VjOOQ IC 



Authors and Collaborators— Continued 



HUGO DIEMER, M.E. 

Professor of Industrial Engineering, Pennsylvania State College 
American Society of Mechanical Engineers 



HERBERT LADD TOWLE, B.A. 

Specialist in Technical Advertising 
Member, Society of Automobile Engineers 
Formerly Associate Editor, The Automobile 



ROBERT J. KEHL, M.E. 

Consulting Mechanical Engineer, Chicago 
American Society of Mechanical Engineers 



EDMOND M. SIMON, B.S. 

Superintendent Union Malleable Iron Company, East Moline, Illinois 



EDWARD B. WAITE 

Formerly Dean and Head, Consulting Department, American School of 

Correspondence 
Member, American Society of Mechanical Engineers 



C. A. MILLER, JR. 

Associate Editor, American Technical Society 
Formerly Managing Editor of National Builder 
Member, American Association of Engineers 



W. R. HOWELL 

President, W. R. Howell and Company, London, England 



WILLIAM K. GIBBS, B.S. 

Associate Editor, Motor Age, Chicago 



JESSIE M. SHEPHERD, A.B. 

Head, Publication Department, American Technical Society 



Digitized by VjOOQIC 



Authorities Consulted 



THE editors have freely consulted the standard technical litera- 
ture of America and Europe in the preparation of these 
volumes. They desire to express their indebtedness, particu- 
larly, to the following eminent authorities, whose well-known treatises 
should be in the library of everyone interested in the Automobile and 
allied subjects. 

Grateful acknowledgment is here made also for the invaluable 
co-operation of the foremost Automobile Firms and Manufacturers 
in making these volumes thoroughly representative of the very latest 
and best practice in the design, construction, and operation of Auto- 
mobiles, Commercial Vehicles, Motorcycles, Motor Boats, etc.; also 
for the valuable drawings, data, illustrations, suggestions, criticisms, 
and other courtesies. 



CHARLES E. DURYEA 

Consulting Engineer 

First Vice-President, American Motor League 

Author of "Roadside Troubles" 



OCTAVE CHANUTE 

Late Consulting Engineer 

Past President of the American Society of Civil Engineers 

Author of "Artificial Flight," etc. 



E. W. ROBERTS, M.E. 

Member, American Society of Mechanical Engineers 

Author of "Gas-Engine Handbook," "Gas Engines and Their Troubles," "The 
Automobile Pocket-Book," etc. 



SANFORD A. MOSS, M.S., Ph.D. 

Member, American Society of Mechanical Engineers 
Engineer, General Electric Company 
Author of "Elements of Gas Engine Design" 



GARDNER D. HISCOX, M.E. 

Author of "Horseless Vehicles, Automobiles, and Motorcycles," "Gas, Gasoline, 
and Oil Engines," "Mechanical Movements, Powers, and Devices," etc. 



AUGUSTUS TREADWELL, Jr., E.E. 

Associate Member, American Institute of Electrical Engineers 
Author of "The Storage Battery : A Practical Treatise on the Construction, 
Theory, and ttee of Secondary Batteries" 



Digitized by VjOOQ IC 



Authorities Consulted— Continued 



BENJAMIN R. TILLSON 

Director, H. J. Willard Company Automobile School 
Author of "The Complete Automobile Instructor" 



THOMAS H. RUSSELL, M.E., LL.B. 

Editor, The American Cyclopedia of the Automobile 

Author of "Motor Boats," "History of the Automobile," "Automobile Driving" 

Self-Taught," "Automobile Motors and Mechanism," "Ignition Timing and 

Valve Setting," etc. 



CHARLES EDWARD LUCKE, Ph.D. 

Mechanical Engineering Department, Columbia University 
Author of "Gas Engine Design" 



P. M. HELDT 

Editor, Horseless Age 

Author of "The Gasoline Automobile" 



H. DIEDERICHS, M.E. 

Professor of Experimental Engineering, Sibley College, Cornell University 
Author of "Internal Combustion Engines" 

>• 

JOHN HENRY KNIGHT 

Author of "Light Motor Cars and Voiturcttes," "Motor Repairing for Ama- 
teurs," etc. 

>• 

WM. ROBINSON, M.E. 

Professor of Mechanical and Electrical Engineering in University College, Not- 
tingham 
Author of "Gas and Petroleum Engines" 



W. POYNTER ADAMS 

Member, Institution of Awtomobile Engineers 
" Author of "Motor-Car Mechanisms and Management" 



ROLLA C. CARPENTER, M.M.E., LL.D. 

Professor of Experimental Engineering, Sibley College, Cornell University 
Author of "Internal Combustion Engines" 

ROGER B. WHITMAN 

Technical Director, The New York School of Automobile Engineers 
Author of "Motor-Car Principles" 

.Google 



Digitized by VjOOQI 



Authorities Consulted— Continued 



CHARLES P. ROOT 

Formerly Editor, Motor Age 

Author of "Automobile Troubles, and How to Remedy Them" 

W. HILBERT 

Associate Member, Institute of Electrical Engineers 
Author of "Electric Ignition for Motor Vehicles" 



SIR HIRAM MAXIM 

Member, American Society of Civil Engineers 
British Association for the Advancement of Science 
Chevalier Legion d'Honneur 
Author of "Artificial and Natural Flight," etc. 



SIGMUND KRAUSZ 

Author of "Complete Automobile Record," "A B C of Motoring" 

JOHN GEDDES McINTOSH ' 

Lecturer on Manufacture and Application of Industrial Alcohol, at the Poly- 
technic Institute, London 
Author of "Industrial Alcohol," etc. 



FREDERICK GROVER, A.M., Inst.C.E., M.I.Mech.E. 
Consulting Engineer 
Author of "Modern Gas and Oil Engines" 



FRANCIS B. CROCKER, M.E., Ph.D. 

Head of Department of Electrical Engineering, Columbia University 
Past President, American Institute of Electrical Engineers 
Author of "Electric Lighting," Joint Author of "Management of Electrical 
Machinery" 



A. HILDEBRANDT 

Captain and Instructor in the Prussian Aeronautic Corps 
Author of "Airships Past and Present" 



T. HYLER WHITE 



Associate Member, Institute of Mechanical Engineers 
Author of "Petrol Motors and Motor Cars" 



Google 



Digitized by UOOQ 



Authorities Consulted— Continued 



ROBERT H. THURSTON, C.E., Ph.B., A.M., LL.D. 

Director of Sibley College, Cornell University 

Author of "Manual of the Steam Engine," "Manual of Steam Boilers," etc. 



MAX PEMBERTON 



Motoring Editor, The London Sphere 
Author of "The Amateur Motorist" 



HERMAN W. L. MOEDEBECK 



Major and Battalions Kommandeur in Badischen Fussartillerie 
Author of "Pocket-Book of Aeronautics" 



EDWARD F. MILLER 

Professor of Steam Engineering, Massachusetts Institute of Technology 
Author of "Steam Boilers" 



ALBERT L. CLOUGH 

Author of "Operation, Care, and Repair of Automobiles" 

^* 

W. F. DURAND 

Author of "Motor Boats," etc. 



PAUL N. HASLUCK 

Editor, Work and Building World 
Author of "Motorcycle Building" 



JAMES E. HOMANS, A.M. 

Author of "Self-Propelled Vehicles" 

R. R. MECREDY 

Editor, The Encyclopedia of Motoring, Motor News, etc. 

S. R. BOTTONE 

Author of "Ignition Devices," "Magnetos for Automobiles," etc. 

LAMAR LYNDON, B.E., M.E. 

Consulting Electrical Engineer 

Associate Member, American Institute of Electrical Engineers 

Author of "Storage Battery Engineering" 



Digitized by VjOOQIC 



'I. 



Digitized by 



Google 



51 

3 * 
II 

p 



Digitized by LjOOQ IC 



Foreword 



THE period of evolution of the automobile does not 
span many years, but the evolution has been none 
the less spectacular and complete. From a creature 
of sudden caprices and uncertain behavior, it has become 
today a well-behaved thoroughbred of known habits and 
perfect reliability. The driver no longer needs to carry war 
clothes in momentary expectation of a call to the front. 
He sits in his seat, starts his motor by pressing a button 
with his hand or foot, and probably for weeks on end will 
not need to do anything more serious than feed his animal 
gasoline or oil, screw up a few grease cups, and pump up a 
tire or two. 

C, And yet, the traveling along this road of reliability and 
mechanical perfection has not been easy, and the grades 
have not been negotiated or the heights reached without 
many trials and failures. The application of the internal- 
combustion motor, the electric motor, the storage battery, 
and the steam engine to the development of the modern 
types of mechanically propelled road carriages, has been a 
far-reaching engineering problem of great difficulty. 
Nevertheless, through the aid of the best scientific and me- 
chanical minds in this and other countries, every detail 
has received the amount of attention necessary to make it 
as perfect as possible. Eoad troubles, except in connection 
with tires, have become almost negligible and even the 
inexperienced driver, who knows barely enough to keep to the 
road and shift gears properly, can venture on long touring 
trips without fear of getting stranded. The refinements 
in the ignition, starting, and lighting systems have added 
greatly to the pleasure in running the car. Altogether, the 
automobile as a whole has become standardized, and unless 
some unforeseen developments are brought about, future 
changes in either the gasoline or the electric automobile 
will be merely along the line of greater refinement of the 
mechanical and electrical devices used. 



Digitized by VjOOQ IC 



^ Notwithstanding the high degree of reliability already 
spoken of, the ears, as they get older, will need the atten- 
tion of the repair man. This is particularly true of the 
ears two and three seasons old. A special effort, therefore, 
has been made to furnish information which will be of value 
to the men whose duty it is to revive the faltering action of 
the motor and to take care of the other internal troubles 
in the machine. 

Q Special eifort has been made to emphasize the treatment 
of the Electrical Equipment of Gasoline Cars, not only be- 
cause it is in this direction that most of the improvements 
have lately taken place, but also because this department of 
automobile construction is least familiar to the repair men 
and others interested in the details of the automobile. A 
multitude of diagrams have been supplied showing the con- 
structive features and wiring circuits of the principal sys- 
tems. In addition to this instructive section, particular 
attention is called to the articles on Welding, Shop In- 
formation, and Garage Design and Equipment. 



Digitized by VjOOQlC 



Table of Contents 



VOLUME VI 
Gasoline Tractors . . By Charles B. Hay war d\ Page *ll 

Analysis of Tractor Mechanisms: Relation of Tractor to Automobile — 
Classes of Tractors: Development of Tractor Industry, Lack of Stand- 
ardization, Types of Tractors — Selecting Tractor: Demonstrations no 
Criterion, Financial Return, Size of Farm, Size of Tractor (First Cost, 
Margin of Safety, Power for Belt Work, Factors Governing Capacity) — 
Tractor Motors: Steam vs. Internal Combustion, Superiority of Four- 
Cycle Motor, Motor Parts, Four-Cycle Principle, Pressure and Temper- 
ature, Grouping of Motor Parts, Relation of Groups (Mechanical, Fuel- 
Supply System, Ignition System, Operations), Value of Skilled Operator — 
Valves and Valve Timing: Placing of Valves, Valve Details, Camshaft 
and Timing Gear, Timing Valves, Lead and Lag of Valve Movement, 
Need of Checking Valves, Sixteen-Valve Engine — Fuel Supply System: 
Fuels Available, Vaporizing Fuels, Proportion of Air to Gas, Spraying 
Process, Effect of Increasing Speed, Heating Requirements, Gasoline and 
Kerosene Carburetor, Need for Cleaning Air, Tractor Air Conditions Bad, 
Types of Air Cleaners (Air-Washer Type, Centrifugal Type, Felt Baffle 
Type, Attention Required) — Lubricating System: Effect of Temperature 
and Pressure, Types of Systems (Splash, Modified Splash, Force-Feed, 
Fresh-Oil), Necessity for Discarding Used Oil — Cooling System: Heat 
Efficiency of Motors, Types of Cooling Circulation, Protection of Radi- 
ator, Auto Experience Misleading — Ignition System: Importance of 
Ignition, Electrical . Principles, Types of Ignition Systems (Low-Tension 
Ignition, High-Tension Ignition), Make and Break Mechanism, Safety 
Spark Gap, Low-Tension Magneto, High-Tension Magneto, Spark Plugs, 
Wiring, Magneto Impulse Starter — Types of Motors: Horizontal Engine, 
Horizontal Opposed — Control Systems: Engine Governors, Tractor 
Clutches, Friction Drive — Tractor Transmissions: Automobile Practice, 
Types — Final Drive — Tractor Operation: Motor: Spare Parts — Trans- 
mission — Running Gear — Lubrication: General, Clutch, Running Gear — 
Valves — Pistons — Carburetors — Cooling System — Horsepower Rating — En- 
gine Troubles: Failure to Start, Operation, Engine Noises — Clutch and 
Transmission — Housing Tractor 

Commercial Vehicles . . .By Charles B. Hayward Page 181 

Introduction: Development of Field, Scope of Commercial Vehicle, Stand- 
ard Design, Classification — Electric Vehicles: Range of Use — Advantages 
— Power Efficiency — Electric . Delivery Wagon: Design, Motive Power, 
Shaft Drive, Worm Gear Transmission, Shaft and Chain Transmission, 
Unit-Wheel Drive, Current and Current Control, Brakes, Tires — Electric 
Tractors — Industrial Trucks — Electric Trucks: Classification, Character 
of Chassis — Gasoline-Driven Vehicles: Gasoline Delivery Wagons: Auto- 
car, White — Gasoline Trucks: Motor Design, Ignition, Carburetors, Cool- 
ing Systems, Lubrication, Motor Governors, Clutches, Transmission, Side- 
Chain Drive, Worm Drive, Front Drives, Four-Wheel Drives — Electric 
Transmission — Springs — Brakes — Trailers 

Electric Automobiles . . . By Charles B. Hayward Page 261 

Introduction — Storage Battery: Construction and Action of Typical Cell: 
Electrolyte, Hydrometer, Process of Charging, Discharge, Efficiency, Sul- 
phating, Restoring Sulphated Battery, Cell Capacity, Measurement of 
Capacity, Rate of Discharge, Safe Discharge Point — Types of Cells: 
General Characteristics, Ironclad Exide Type, Starting Batteries, Edison 
Battery — Motor: Essentials of Motor — Principle of Rotation — Armature 
— Capacity for Overloads — Parts of Motor — Motor Speeds — Transmission: 
Similarity to Gasoline Practice — Usual Gear Reductions — Chain Drive — 
Gear Drive — Worm Drive — Control: Counter E.M.F. — Controller — 
Methods of Control — Office of Shunt — Electric Brake — Care and 
Operation of Electrics: Charging Battery: Sources of Direct Current, 
Sources of Alternating Current, Methods of Charging, Testing Progress 
of Charge, Boosting — Care of Battery — Renewal of Battery — Putting 
Battery Out of Commission: Storage, Packing Battery, Standard In- 
structions for Storage Batteries — Sources of Power Loss — Tires and 
Mileage — Electric Indicating Instruments and Their Use 

Glossary Page 397 

Wiring Diagram Index Page 427 

Index Page 435 

•For page numbers, see foot of pages. 

tFor professional standing of authors, see list of Authors and Collabo- 
rators at front of volume. 



Digitized by VjOOQIC 



»*» 



Digitized by VjOOQIC 



o 1 

a* 
5?l 



*3 5* 

I a 

si 



Digitized by VjOOQIC 



Digitized by VjOOQIC 



GASOLINE TRACTORS 

PART I 



INTRODUCTION 

Relation of Tractor to Automobile. At first sight it appears to 
be rather a fortunate coincidence that the man to whom the trac- 
tor will prove of the greatest benefit is he who has found most 
advantage in the automobile — the progressive American farmer. 
The automobile has proved a veritable godsend to the farmer, and 
there is no question but that he has thoroughly mastered it. He 
appreciates that it is a piece of machinery and as such can only be 
kept in satisfactory operating condition by proper attention; and 
further, that even despite attention it is subject to breakdown at 
times. Having acquired this knowledge of an automobile by experi- 
ence, the prospective purchaser of a tractor naturally feels perfectly 
competent to judge the merits and demerits of the various types 
offered and to give the one he buys whatever attention it may 
need to keep it operating satisfactorily. This is a mistake and has 
proved a more or less costly one to many farmers who have pro- 
ceeded on such an assumption. The tractor is driven by a gasoline 
or kerosene engine, it has a gear set, clutch, and final drive — all 
counterparts of the automobile — but it is not an automobile 
any more than an aeroplane or a motorboat is, and the attention 
that will suffice to keep an automobile going will fall far short of 
what a tractor requires. Unlike an automobile, the tractor is 
always operating at full, or almost full, load. Moreover it oper- 
ates for ten, twelve, or even eighteen hours a day under this load. 
Its requirements are those of the mogul freight engine rather than 
those of the high-speed passenger locomotive. 

Need of Judgment in Selection of Tractor. Not every one can 
hope to operate a tractor satisfactorily, but the experience of those 
who have acquired the many thousand machines turned cut in the 
last few years shows that, given proper judgment in the selection 
of a tractor for the work it is to perform and the right kind of 

11 



2 GASOLINE TRACTORS 

attention to its needs, it wfll do all or more than b claimed for it. 
Buying a tractor may be likened ir some respects to building a 
house. Many people never succeed in building just the house 
they want until they have made two or three attempts. This is 
equally true of tractor purchases; many, farmers do not succeed 
the first time in buying the tractor they should have, but in the 
end the value of the experience gained usually offsets its cost. 

CLASSES OF TRACTORS 

Development of Tractor Industry. According to a recent issue 
of a directory of the industry one hundred and thirty-five different 
American manufacturers are building over two hundred models of 
tractors. This statement holds good only for the time at which it 
is written since both the number of manufacturers in the field and 
the number of models the old and the new entrants are turning 
out are constantly on the increase. The use of tractors on large 
farms dates back almost half a century, but up to less than ten 
years ago they were all of the steam-driven type. Their first cost 
as well as the expense of maintenance made them practical only 
on very large farms where skilled labor is constantly employed. 
This bit of history is mentioned merely to emphasize the infancy 
of the industry as it now exists, a factor that makes it exceedingly 
difficult to classify the product of all the manufacturers in the 
field and even harder for the prospective purchaser to make his 
selection of a machine. The business of building gasoline- and oil- 
driven tractors only dates back to about 1910, and for the first 
five years of its existence its progress was not very rapid. Conse- 
quently it is only during the last four years or so that most of the 
many manufacturers mentioned have entered the field in response 
to the great demand for tractors on the part of the farmers, caused 
by the acute shortage of farm labor and the corresponding increase 
in wages. 

Lack of Standardization. When an industry comes into 
existence almost overnight, as in the present instance, every manu- 
facturer proceeds along individual lines in the design of his machine 
with the result that the divergence in types is almost as note- 
worthy as the number competing. The tractor industry now finds 
itself in about the same position as did the automobile industry 

12 



GASOLINE TRACTORS 3 

fifteen years earlier in that the machines differ widely in design 
and construction, horsepower ratings bear little relation to the 
dimensions or speed of the motor, and weights for the same horse- 
power are often far apart. There is accordingly an entire lack of 
standardization where any of the essentials are concerned though 
efforts to remedy this situation by the Society of Automotive 
Engineers are already well under way. It is scarcely to be 
expected, however, that the recommendations adopted can come 
into general use for two or three years at least. Meanwhile, many 
thousands of tractors are being turned out annually, and the pro- 
spective purchaser must make his selection of a machine from 
those offered, since conditions make it impossible to wait for the 
perfected tractor to be produced several years from now. 

Types of Tractors. Regarded from the mechanical standpoint, 
the large number of machines now being built may be classified in 
groups according to some feature of design, such as the type of 
motor employed, the method of transmitting the power, the man- 
ner of securing traction, and the number of wheels, where the lat- 
ter are used. For example, when classified according to type of 
motor, there would be a group consisting of those tractors using a 
slow-speed two-cylinder engine adapted from stationary-engine 
practice, and a second group of those employing a high-speed four- 
or six-cylinder motor designed along lines that have been made 
familiar on the automobile. When classified according to trans- 
mission of power, the tractors using a drive through a clutch, 
which are in the majority, would fall in one group and those 
employing a friction type of drive in another. On the basis of the 
method of obtaining traction we would have a group consisting of 
tractors employing wheels, also in the majority, and a group com- 
posed of the so-called caterpillar, or tracklaying, type and its 
numerous modifications. A subdivision of the class using wheels 
can be made to cover three- and four-wheel types since many 
machines differ chiefly in this respect. As a matter of fact, sub- 
divisions of practically every one of these classes are possible. 
For instance, in some three-wheel machines there are two driving 
wheels, while in others but one is employed. These numerous 
differences are cited merely to point out the great range of varia- 
tion that exists. 

13 Digitized by VjOOQ IC 



4 GASOLINE TRACTORS • 

SELECTINQ TRACTOR 

Work Done on Demonstration No Criterion. Involving, as it 
does, an investment larger than that of almost any other single 
farm machine, the selection of a tractor should be made the sub- 
ject of as much study and investigation as the prospective buyer 
can possibly give. One of the commonest fallacies in tractor buy- 
ing is to judge the merits of the machine by the class of work it 
does, the term "work" in this connection being applied almost 
entirely to plowing since the latter represents the heaviest service 
to which the tractor is put. It should be borne in mind that the 
tractor is nothing more than the motive power, and neither its 
reliability nor its value as a farm machine can be judged from the 
character of the plowing it does on a demonstration. Good or 
poor plowing depends entirely upon the plow itself and the methods 
used in its handling, so that a poor tractor properly hitched to the 
right type of plow and in the hands of a skilled operator will do 
better work than the best tractor that can be built will turn out 
when handled improperly. The method of hitching the plows to 
the tractor governs not only the quality of work turned out but 
likewise the amount of power consumed in doing it, granting that 
the right type of plow is being used for the soil under considera- 
tion. It would be just as sensible to judge the value of a 
team of horses by the character of the furrows they turned in 
plowing. 

Financial Return. It has become customary to criticize Amer- 
ican farming methods as compared with European solely upon the 
difference in production per acre, the fact that the application of 
intensive cultivation by hand labor to very small areas is account- 
able for the disparity being lost sight of entirely. American agri- 
cultural methods produce more per acre for each man employed 
than is grown anywhere else in the world, and this is due solely to 
the application of farm machinery to production on a larger scale 
than has ever been attempted abroad. This has a direct bearing 
on the purchase of a tractor, since the capital required for the lat- 
ter must be invested for one of two reasons: either the tractor 
will enable its owner to cultivate the same number of acres more 
economically, or it will place him in a position to cultivate a 
greater number of acres with the same number of "hands." 



14 



. GASOLINE TRACTORS 5 

The impression has been more or less general that the first of 
these two reasons, "It will do the work cheaper/' is the chief one 
for purchasing a tractor. Investigations carried out by the Depart- 
ment of Agriculture, however, have shown that this reason is not 
valid. Taking into account the capital outlay required, the cost of 
operation, and the depreciation, and considering the average life of 
a tractor as seven or eight years, it has been found that plowing 
cannot be done any more cheaply with a tractor than with horses, 
but that the use of the tractor does enable the farmer to cultivate 
a substantially increased number of acres with the same number 
of men. Out of the large number of farms investigated, a major- 
ity of the owners found it necessary to increase their acreage after 
purchasing a tractor in order to use their machines most effi- 
ciently. In other words, the same crops could not be raised any 
more cheaply with the tractor than without it, but much larger 
crops could be raised by increasing the acreage under cultivation. 
This naturally applies more particularly to small farms, by which 
is meant those of 150 acres or less, taking the country as a whole, 
since what is considered a small farm in the Middle West would 
be thought quite the contrary in New England. 

Size of Farm. It goes without saying that a tractor will not 
prove a profitable investment on farms of such a size that all the 
land available for cultivation may be as easily worked by horses 
in the time allowed, which classification would cover all farms hav- 
ing 100 acres or less of cultivable land since only a portion of the 
total acreage is open to cultivation on any farm. Many farmers 
consider the purchase of a tractor on the assumption that its excess 
capacity can be taken care of by doing "custom work/' or plowing 
for neighbors. In a number of cases of this kind that were inves- 
tigated the charge made for this work was not sufficient to leave a 
profit after deducting the cost of operation and the interest on the 
investment, so that the farmer would have been better off without 
undertaking this extra work. As a means of paying for the trac- 
tor when the owner's farm is not sufficiently large to absorb its 
full capacity, this practice did not show a profit that would war- 
rant the investment in a tractor, since, as before stated, the 
charges were too low to cover the cost of operation, while 
increasing the rates to a point that would leave a profit would 

15 



6 GASOLINE TRACTORS 

result in a falling off in the demand as the renter could do the 
same work for considerably less with horses. 

Judging from the results of the investigations in question, it 
will not pay the owner of a 150-acre farm of which not more than 
100 are cultivable to invest in a tractor unless he can add from 20 
to 50 acres to that under cultivation. This, of course, is a general 
statement that may be subject to modification in numerous 
instances where specially favorable conditions make the use of' a 
machine advantageous. But this statement as well as the pre- 
ceding matter is intended chiefly to emphasize to the prospective 
purchaser of a tractor the fact that it is unwise to make the invest- 
ment required in anticipation of doing the same amount of work 
much more economically than it can be performed with horses. 

Size of Tractor. First cost is naturally the chief item con- 
sidered in the purchase of a tractor, and in this connection true 
•economy is to be found in the selection of a machine that is not 
only of good quality, properly designed and well built for the 
work it is to do, but that likewise has ample capacity to handle it 
without overloading. It will prove as expensive in the long run to 
pay for a good small machine that must be overloaded to do the 
work required as to buy a cheap machine of any size. In either 
case the repair bills and the time lost through delays at the height 
of the season are apt to make the buyer regret his choice, if, in 
fact, he is not led to condemn tractors altogether. In this con- 
nection, however, the skill and experience of the operator are fac- 
tors which have a very important bearing on the successful use of 
the machine and largely govern the amount of time that it is out 
of service due to breakdowns. This is dwelt upon at greater 
length in later paragraphs. 

Tests have demonstrated that at the maximum speed of plow- 
ing recommended for all tractors, that is, 2\ to 2\ miles per hour, 
a two-gang plow will not cover much more ground in a day of ten 
hours when drawn by a machine than when pulled by horses. In 
other words, the advantage of the tractor-drawn two-gang plow 
over horse work is so small that it usually does not pay to buy a 
machine whose maximum capacity is two plows. Whether it be a 
tractor or any other type of machine, it is not good practice to 
depend upon running it at its maximum capacity continuously. 



16 



GASOLINE TRACTORS 7 

The machine will not do as good work and it will be much more 
subject to frequent breakdown than where it has power in reserve 
to meet emergencies that will seriously overload a machine that is 
already working at its full output. 

The number of plows that any given machine is capable of 
pulling depends upon so many other factors besides its power rat- 
ing that it is often misleading to term a tractor a two-, three-, or 
four-plow machine, as the case may be. The depth of the furrow, 
the character and condition of the soil, and the method of hitching 
all influence this to such an extent that a machine capable of pull- 
ing three plows under favorable conditions might make a very 
poor job with two where the soil conditions were not so good or 
the plows were not properly hitched. 

Margin of Safety Needed. It should be borne in mind that 
any machine will give the most satisfactory service and have the 
longest useful life when operated continuously at not more than 75 
per cent of its rated capacity. Expense incident to delays as well 
as the cost of repairs will accordingly be minimized when a 
machine larger than is actually required is selected and is operated 
at less than its full capacity. Experienced tractor operators have 
proved this in many instances by investing in four-plow machines 
and pulling but three plows. It does not pay to load a machine 
to its limit since it cannot carry such a load continuously and give 
satisfactory service, so that in selecting a tractor the chief points 
to bear in mind are not to buy a lightly or cheaply built machine; 
and not to select a machine so small that it can only do the work 
required by working continuously at full load. 

Power for Belt Work. While plowing constitutes more than 
one-half the work for which the tractor is required, it would 
pay few farmers to invest in a machine for that purpose alone. 
All tractors are designed to be used as stationary power plants as 
well, and one-third or more of the service demanded of them con- 
sists of driving other machines, such as threshers or ensilage cut- 
ters, or, as it is usually termed, belt work. Unless a machine has 
ample power for this, it will not be found satisfactory since there 
is usually a tendency under such conditions to load it to the stall- 
ing point and when a cutter has been "choked down," much val- 
uable time is lost in getting it under way again. 

17 Digitized by G00gle 



8 GASOLINE TRACTORS 

A tractor that is not powerful enough to do all the work 
required of it is not likely to prove a satisfactory investment, 
though an error may also be made by going to the other extreme 
and selecting a machine of such a size that it is too expensive to 
operate on many of the jobs that a tractor of the proper size 
would perform economically. 

Factors Governing Capacity. Why a machine that will pull 
three plows very satisfactorily under some conditions will with 
difficulty do good work with only two bottoms in other locations 
will be readily apparent from a consideration of the difference in 
drawbar pull required for plowing different soils. The average 
resistance of soils is given approximately in Table I. 

While the figures in Table I have been drawn from experience, 
the draft of a tractor plow can only be approximated, since the 
condition of the plow itself and the method of hitching are of the 
greatest importance. The figures given are based upon the sup- 
position that the plow is clean, sharp, and properly hitched so as 
to cut easily. When a plow is dull or does not scour well, the 
power required to draw it will be substantially increased. This is 
equally true when a plow is not leveled or is out of line in any way. 

The draft likewise increases in proportion to the grade and 
the figures given are based upon plowing on level ground. For 
each 1 per cent rise in grade, that is, for each foot of vertical lift 
in each 100 feet of horizontal travel, 1 per cent of the combined 
weight of the tractor and the plows must be added to the draft. 
For example, assume a tractor weighing 5000 pounds and hauling 
four plows each weighing 250 pounds, making the total 6000 pounds: 
the maximum draft of the four plows in corn stubble, plowing 6 
inches deep, would be 3200 pounds, to which it would be necessary 
to add 60 pounds for each 1 per cent increase in grade. Even on 
rolling prairie land, which is ordinarily thought of as being level, 
the dips and hollows often represent 10 per cent grades for short 
distances, and in this case they would necessitate adding 600 pounds 
to the draft required. 

When planning to buy a tractor to do certain work, keep the 
figures given in the table in mind; consider the character of the 
soil, the grades, the depth of the furrow, and the horsepower rat- 
ing of the machine desired — and it is always well to discount that 

* ' Digitized by VjOOQIC 



GASOLINE TRACTORS 

TABLE I 
Average Resistance of Soils 



Coil 


Pounds per 


& Inches 


8 Inches 


Square Inch 


Deep 


Deep 


Sandy loam 


4-6 


600- 800 


750- 950 


Corn stubble 


6 


700- 800 


900-1000 


Wheat stubble 


8 


800- 900 


1000-1100 


Light clay 


12 


800-1200 


1000-1400 


Medium clay 


14 


900-1400 


1200-1500 


Heavy clay in good plowing condition 


16 


1600-2000 


1800-2100 


Sod or heavy clay, medium moisture 


18 


2500-3000 


2700-3100 


Gumbo — dry, hard 


36 


2600-3200 


2800-3300 



horsepower rating somewhat. It will also pay to keep these 
figures in mind when the over-enthusiastic salesman begins to make 
claims. 



ANALYSIS OF TRACTOR MECHANISMS 
TRACTOR MOTORS 

Steam Tractors vs. Internal-Combustion Tractors. Although 
tractors have been used in this country for almost half a century, 
they were all steam driven until less than ten years ago, so that 
the present widespread and rapidly increasing adoption of the 
tractor is due to the remarkable development of the internal- 
combustion motor, which, in turn, is largely the result of the great 
strides the automobile industry has made since 1900. The present 
work is accordingly confined to tractors with such motors since, 
although steam tractors will continue to be used on some of the 
very large farms on which they have been employed so long, they 
are not available to the average purchaser of a tractor and, at 
best, it will be only a matter of a comparatively few years before 
they will have been displaced by the internal-combustion type in 
most parts of the country. ' 

Superiority of Four=Cycle Motor. The experience of the auto- 
mobile manufacturer as well as that of the stationary oil-engine 
builder has demonstrated that of the several types of internal- 
combustion motors that may be used that based upon the so-called 
four-cycle method of operation combines the fewest drawbacks 
with the greatest number of advantages and is accordingly the 



19 



Digitized by 



Google 



10 GASOLINE TRACTORS 

most practical for general use. The two-cycle motor has never 
proved successful owing to its inefficiency where fuel consump- 
tion is concerned, while other types involve the use of excessive 
weights for the power generated. 

Motor Parts. Assuming the motor to have but one cylinder, 
a four-cycle motor consists of a cylinder, inlet valve and exhaust 
valve, piston, piston rings, piston pin, connecting rod, crankshaft 
and bearings, flywheel, camshaft, valve springs and crankcase. 
Its accessories are a carburetor (or fuel-mixing device), magneto or 
other method of generating electric current, spark plug for igniting 
the fuel, lubricating system, cooling system, and the necessary 
piping for supplying lubricating oil and for conducting the cooling 
water between the cylinder jackets and the radiator, the fuel mix- 
ture from the carburetor to the combustion chamber of the cylin- 
der, and the exhaust gases away from the latter after they have 
been burned. A circulating pump may or may not form a part of 
the cooling system according to the method of circulation employed. 
These auxiliaries, plus a fan to assist in the cooling of the water or 
oil in the radiator of the cooling system, complete the motor and 
the addition of any number of cylinders only involves the duplica- 
tion of those parts directly attached to or working in the cylinder, 
such as valves, pistons, and connecting rods with, of course, the 
provision of an additional crankthrow on the crankshaft for each 
additional cylinder. 

Four-Cycle Principle. Intake Stroke. The operation of the 
motor is based upon a cycle, or recurrence of operations, consisting 
of four distinct parts. Starting with the piston at the upper dead 
center, the first of these operations is the intake, or auction, 
stroke. The inlet valve has been opened through the revolution of 
the camshaft bringing the cam in contact with the valve tappet 
and raising the valve off its seat, Fig. 1. The piston is a gas- 
tight fit in the cylinder, being sealed by the piston rings, which 
press out against the cylinder walls, and by the presence of a 
film of lubricating oil between the piston and the cylinder. The 
downward travel of the piston accordingly creates a partial vacuum 
(negative pressure, or less than atmospheric) in the cylinder, and 
the atmospheric pressure (14.7 pounds at sea level), acting upon 
the liquid fuel in the carburetor, forces the liquid up through the 



20 



GASOLINE TRACTORS 



11 



spray nozzle of the carburetor and also draws a predetermined 
volume of air up through this spray, thus forming a fuel mixture 
which is forced into the cylinder. The action of the piston on 
this first part of the cycle is exactly the same as that of a pump 
in drawing water out of a well. The water is forced up into the 
pump, following the plunger owing to the decreased pressure in the 
pump barrel caused by the 
stroke of the plunger and to 
the outside pressure of the air 
on the surface of the water. 
Compression Stroke. 
When the piston reaches the 
limit of its travel, or lower 
dead center, the inlet valve 
closes and the piston in rising 
then compresses the fuel mix- 
ture against the head of the 
cylinder, the valves also being 
gas tight. This is the second 
part of the cycle, or the com- 
pression stroke, and gives to 
the fuel mixture what is known 
as the initial compression. This 
stroke has an important bear- 
ing on the power output of the 
motor since it renders the com- 
bustion of the fuel more rapid 
and complete and also in- 
creases the pressure developed 

when the Charge is fired. The Fi»j- 1-4. Strokes of Four-Part Cycle: 1. Intake; 

° # m 2. Compression; 3. Power; 4. Exhaust 

initial compression used in the 

average gasoline motor ranges from 50 to 80 pounds per square inch, 
and the higher it is, the more power the motor develops, other 
factors such as cylinder dimensions and number of cylinders being 
the same. In the case of gasoline, however, this initial pressure 
is limited to 90 pounds per square inch since the heat generated 
by compression above that point would cause the ignition of the 
mixture. In kerosene, alcohol, or low-grade fuel engines, it may 




21 



Digitized by 



Google 



12 GASOLINE TRACTORS 

be much higher, but in this case a compression release must be 
fitted to the engine in order that it may be turned over by hand 
for starting. 

Power Stroke. The third part of the cycle begins with the 
firing of the charge by the passage of a spark at the plug, and 
the piston then starts downward on the power stroke. Just before the 
piston reaches the lower dead center on this stroke, the exhaust 
valve is lifted by the camshaft and the remaining pressure in the 
cylinder, which cannot be utilized for driving the piston, is allowed 
to escape. A very large part of the heat value of the fuel is 
wasted in this manner through the exhaust, but the drop from the 
very high pressure at the moment of ignition is so rapid that no 
advantage is to be gained from lengthening the stroke beyond a 
certain point in an attempt to utilize a greater percentage of the 
pressure. 

Exhaust Stroke. The following upward movement of the pis- 
ton is termed the exhaust stroke and serves to clear the cylinder of 
the remaining burned gases in preparation for the succeeding suc- 
tion stroke, which recommences the cycle. Although it is one of 
the three idle sirokes of the four-cycle method of operation, the 
exhaust stroke is quite as important as those which precede it 
since, unless the cylinder is swept clear of the burned gases of the 
previous explosion as completely as possible, a volume of dead gas 
is left to occupy space which should be filled with fresh fuel and 
the amount of power developed on succeeding strokes is reduced 
in proportion. This is one of the chief defects of the two-cycle 
method of operation, in which compression immediately follows 
the power stroke, there being no exhaust stroke or suction stroke. 
As a result, a considerable percentage of the cylinder space is 
always filled with burned gases and the time available for the 
power stroke is so short that part of the fresh gas escapes unburned. 
In the four-cycle method, upon the completion of the exhaust 
. stroke, the exhaust valve closes and the inlet valve opens, begin- 
ning a new cycle. The relative positions of the piston and the 
valves during the compression, power, and exhaust strokes are 
shown in Figs. 2, 3, and 4. 

Pressure and Temperature. While even the most skilled 
operator of a traction engine need not be conversant with the 

22 



GASOLINE TRACTORS 13 

intricacies of its design nor with the scientific aspect of its opera- 
tion, a knowledge of what goes on inside the cylinder will be 
found an aid to a clearer understanding of the engine itself and 
the principles on which it works. The internal-combustion motor 
is a heat engine pure and simple, and each part of its cycle is 
attended by an increase or decrease in pressure and temperature. 
One is a function of the other, a given degree of pressure resulting 
in an equivalent rise in temperature, and this fact is taken advan- 
tage of in determining the pressure and the temperature in the 
cylinder by means of an indicator, the use of which need not be 
described here since it is only used by designers in the shop. 

Range of Pressure and Temperature. Some idea of the great 
range of pressure and temperature inside the cylinder during but 
two parts of the cycle, the compression and power strokes*, may be 
gained by assuming that the motor is operating on a summer day 
with the surrounding temperature at 70° F. The temperature of 
the entering mixture will then be raised to approximately 100° F. 
or more through the use of hot air in forming the fuel mixture by 
taking the air supply from a "stove" attached to the exhaust 
manifold or by using exhaust gases direct from the engine and 
also through having a water jacket surrounding the intake mani- 
fold. Without these heating devices the mixture would be con- 
siderably cooler than the atmosphere since the conversion of the 
liquid fuel into a vapor is attended by the abstraction of heat 
from the air. Assuming that the engine has been running, the 
end of the previous exhaust stroke leaves the interior of the 
cylinder at a temperature of approximately 260° F. and the incom- 
ing mixture is further heated by contact with the cylinder walls 
and the piston head. At the moment of intake the pressure in the 
cylinder is slightly less than atmospheric. During the compression 
stroke this pressure is raised to 50-85 pounds, depending upon the 
amount of initial compression given, and the temperature rises to 
a point between 800° and 900° F. Upon the gases being ignited, 
their tremendous expansion in the confined space raises the pres- 
sure to 225-250 pounds per square inch with an increase in tem- 
perature ranging from 2500° to 4000° F., depending upon the 
character of the fuel used. This pressure decreases very rapidly 
as the piston moves outward on the power stroke, the so-called 

2 ? 



14 GASOLINE TRACTORS 

terminal pressure, that is, the pressure at the end of the stroke 
when the exhaust valve opens, reaching 40 to 50 pounds with a 
temperature of approximately 1000° F. The exhaust stroke 
lowers the pressure to approximately that of the surrounding 
atmosphere with a decrease in temperature that is governed to some 
extent by the length of time that the engine has been running. 

Effect of High Temperature. The extreme range of tempera- 
tures inside the cylinder should impress upon the operator of a 
tractor engine the necessity for prompt attention if anything goes 
wrong. For example, in the presence of such great heat as is 
developed by the explosion it will be evident that failure of the 
lubrication or of the cooling system can cause serious damage in a 
very brief period. Pistons will score and scratch the cylinder 
walls, valves will warp, bearings will be burned out, and finally 
the pistons will bind hard and fast, all in the short space of a few 
minutes. In fact, five minutes will suffice to cause damage, the 
repairing of which will take a week and will represent a bill of 
three figures. 

Grouping of Motor Parts. Mechanical Group. The parts nec- 
essary to a four-cycle motor, whether of one or several cylinders, 
have already been outlined. Upon studying these, it will be 
apparent that they may be divided into groups and that each 
group has as its object the carrying out of a certain function in 
the operation of the motor. The foundation of all the groups is 
naturally the chief mechanical group consisting of the cylinders, 
valves, pistons, connecting rods, crankshaft, camshaft, crankcase, 
and flywheel. The functions of this group are to provide a 
container in which the fuel may be compressed and ignited and 
moving parts against which the force of the explosion may act — 
first, to produce linear motion in the stroke of the piston and, sec- 
ond, to convert that motion into rotary motion at the crankshaft. 

Auxiliary Groups. All the other groups really consist of 
auxiliaries, such as the carburetor, heating devices, and intake and 
exhaust manifolds, designed to mix the fuel with the proper pro- 
portion of air, warm it, conduct it to the cylinders, and lead it 
away from the latter after it has been burned. These parts con- 
stitute the second group, or fuel-supply system. The third group 
consists of the apparatus for igniting the fuel in the cylinders and 



24 



Digitized by VjOOQ IC 



GASOLINE TRACTORS 15 

is represented by the magneto (or other method of generating 
electric current), the spark plugs, the connecting cables, and any 
distributing or timing devices necessary when a battery instead of 
a magneto is employed. The fourth group is represented by the 
lubricating system, the function of which is to supply oil to all 
the moving parts; while the fifth group is the cooling system, con- 
sisting of the water jackets of the cylinders, the pump, the radia- 
tor, and the piping connections. On the traction engine there are 
further auxiliaries not necessary on an automobile engine, namely: 
the governor and the air cleaner. A large part of the work of the 
tractor consists in serving as a stationary power plant, and while 
doing belt work it is necessary that a steady engine speed be 
maintained under a wide range of load. Unless the engine were 
automatically governed under such conditions, it would stall when 
the load was increased and race when the load was relieved; and 
racing would be dangerous to the engine itself owing to the great 
stresses set up by the high speed. While not constituting a group 
in itself, the governor may be included in a further group consist- 
ing of the control system, in which the throttle and the spark 
levers represent the hand control, and the governor the automatic 
control of the engine. 

Interrelation of Groups. It will be apparent upon a little 
study of these different groups, or systems, that all are equally 
essential to the operation of the motor and that precedence cannot 
be accorded to any one as compared with the others since the 
failure of any one would prevent the functioning of the rest. An 
understanding of the relations that these groups bear to one 
another will go a long way toward making clear the principles on 
which the engine operates and also the manner in which the differ- 
ent systems must work together in order that it may run satisfac- 
torily. The interdependent functions of the groups are considered 
at some length in the following paragraphs. 

Mechanical Group. Unless the pistons are free to move in the 
cylinders and the crankshaft and the connecting rods on their 
bearings, no movement can result. This free movement of the 
pistons and other working parts is entirely dependent upon the 
lubricating system maintaining a constant supply of oil on all con- 
tacting surfaces. But unless the cooling system continues to 

i 

- Digitized by VljOOQ IC 



16 GASOLINE TRACTORS 

function properly, the fact that the lubricating system is working 
will not keep the motor running since the oil will be burned up on 
coming in contact with the cylinder walls owing to the high tem- 
perature inside the cylinder. 

Fuel-Supply System. Air must be drawn through the carbu- 
retor and mixed with the spray of liquid fuel issuing from the 
carburetor nozzle, but this cannot be done unless the inlet valve 
of the cylinder opens just before or when the piston reaches upper 
dead center on the exhaust stroke, as otherwise there will be no 
difference in pressure between the inside and the outside of the 
carburetor and no suction will result. Nor will the admission of a 
charge to the cylinder be effective unless the inlet valve closes 
when the piston reaches or just after it passes lower dead center 
on the upward stroke as otherwise, instead of being compressed ready 
for firing, the fuel mixture would again be forced out of the cylinder. 

Ignition System. Movement will naturally cease after the 
admission of a charge unless the electric spark takes place at the 
proper moment to fire that charge in order to produce the power, 
or third, stroke of the cycle. The entire failure of the spark will 
prevent further operation; its occurrence too early will stop the 
engine by driving the piston down in the reverse direction before 
it has completed its stroke on compression; and its occurrence too 
late will cause a substantial proportion of the power to be wasted 
although the motor will continue to operate. After the completion 
of the power stroke the mechanical system again enters since, 
unless the exhaust valve opens near the end of this stroke, the 
burned gases will remain in the cylinder and when the inlet valve 
opens, they will be blown back through the carburetor owing to 
the terminal pressure of 40 to 50 pounds per square inch remain- 
ing in the cylinder at the end of the power stroke just before the 
exhaust valve opens. Owing to the high temperature of these 
gases they may ignite the liquid fuel in the carburetor if blown 
back through it. This is known as a back fire, and while failure 
of the exhaust valve to operate is not as common a cause as either 
too lean or too rich a mixture, it is evident that back fire must 
invariably follow unless the exhaust valve does open. 

Summary of Operation. Continued movement of the mechani- 
cal parts of the motor is dependent upon the working of the lubri- 

26 Digitized by G00gle 



GASOLINE TRACTORS 17 

eating system. Lubrication fails unless the cooling system does its 
part to keep the temperature down to a point where the move- 
ment of the parts in contact is possible, as otherwise the oil is 
burned. Unless the inlet valve opens at the right time, the car- 
buretor cannot supply a fuel mixture to the cylinder, while a 
failure of the electric spark to ignite this mixture at the proper 
moment renders the admission of the fuel supply useless. Failure 
of the exhaust valve to permit the escape of the burned gases 
from the cylinder stops further operation by preventing the admis- 
sion of a fresh charge. 

Value of Skilled Operator. It is necessary to take up each of 
these systems in detail and learn the principles upon which its 
operation is based in order to understand more clearly the manner 
in which they must co-operate to produce satisfactory running of 
the engine and also in order to recognize the symptoms at once 
when anything goes wrong and to know the remedy to apply to 
keep the engine going and avoid laying up the machine at the 
time when it is most needed. In the numerous investigations 
undertaken by the Department of Agriculture, some of which 
have been referred to, it was brought out in a most striking man- 
ner that in the majority of cases where repair bills were lowest 
and the most satisfactory service was obtained from the tractor, 
it was due in very large measure to the fact that a skilled 
operator was on the job. 

It has not been a very uncommon thing in the past for manu- 
facturers to advertise that their machines can be driven by a child. 
So can a big mogul freight locomotive be run by any boy with 
strength enough to pull the throttle, but no railroad company 
would entrust valuable machinery to the care of a boy even were 
the danger of collision entirely absent. A tractor cannot be run 
satisfactorily by a boy or a girl, nor can it be so run by a man 
unless he takes the trouble to acquaint himself with its principles 
of operation instead of trusting to luck and experience to acquire 
the necessary information haphazard. In other words, he must 
qualify as a skilled operative by familiarizing himself thoroughly, 
with the sequence of operations responsible for the working of 
the motor and the principles upon which those operations are 
based. 

27 



18 GASOLINE TRACTORS ' 

VALVES AND VALVE TIMINQ 

Placing of Valves. By referring to the description of the four- 
cycle method of operation, it will be seen that it is necessary to 
draw a fuel charge into the cylinder on one stroke, compress it on 
the second stroke, fire it on the third, and exhaust the burned 
gases on the fourth to complete the cycle. There must accordingly 
be valves to control the entrance and escape of the gases, and 
these valves must open and close at certain intervals with relation 
to the rest of the cycle. The placing of these valves depends upon 
the type of motor, of which there are three in general use, namely: 
the L-head motor, in which the valves are all on one side; the 
T-head motor, in which the inlet valves are placed on one side and 
the exhaust on the opposite side; and the valve-in-head type, in 
which the valves are located directly in the cylinder heads. 

Valves in L-Head Motor. The L-head motor forming the 
power plant of the Fordson tractor is shown in Fig. 5 in phantom 
to bring out the details of the valves and valve-operating gear. 
In a motor of this type all the valves are placed on the same side 
of the motor so that in the line of eight valves an inlet and an 
exhaust alternate. The operation of the valves may be traced 
through their entire range of movement in this illustration by 
noting their positions in the different cylinders. Cylinder 2, for 
example, is on the first stroke of the cycle, the intake stroke. 
The inlet valve is accordingly open and the exhaust valve closed. 
Cylinder 1 is shown on the compression stroke, during which both 
valves remain closed. This is also true of the explosion stroke, as 
indicated by cylinder 3. On the fourth stroke of the cycle the 
exhaust valve opens to discharge the burned gases into the air, as 
shown by cylinder 4. (The cylinder numbers mentioned here 
refer to the cylinders counting from the forward end and not to 
the numerals shown on the illustration.) 

Valve Details. The valves used on automobile and tractor 
motors are variously referred to as mushroom and poppet valves, 
the former name referring to their shape and the latter to their 
method of operation. The valve proper consists of a head and a 
stem, and as the valve is subjected to high temperatures, it is 
either made of cast iron welded to a steel stem or is a piece of 
nickel steel or other heat-resisting metal. Unless some expedient 



28 Digitized by GoOgk 



GASOLINE TRACTORS 19 

of this nature is employed, the valve heads are apt to warp under 
the terrific heat, this being particularly true of the exhaust valves. 
The stem passes down through a guide drilled and reamed in the 
cylinder casting itself, and below the point where it leaves this 
guide the stem is surrounded by a heavy helical spring. This 
spring is held against the guide at its upper end and against a 
washer at its lower end. A key passing through a slot in the valve 
stem itself holds this washer in place. The valve is accordingly 
held down on its seat by a strong spring, and it is the pull of this 
spring that returns it to its seat with a snap, or pop, after it has 
been opened. The inch or so of the valve stem extending below 
the spring washer contacts with the valve push rod when the latter 
is lifting the valve off its seat, but in order that the valve may 
come down squarely on its seat when closing, the valve stem 
and push rod should not be in contact normally. This distance, 
or clearance, that must exist between the valve stem and the 
valve push rod is not indicated in the illustration since, in this 
case, the valve push rod also acts to a certain extent as a lower 
guide, the valve stem entering its upper end for a short distance. 

Camshaft and Timing Gear. At its lower end the valve push 
rod rides on a cam, and the position of this cam with relation to 
the camshaft determines the point at which the valve will open 
and close. There is, of course, a cam for each valve, and as their 
positions must remain absolutely fixed, they are usually drop- 
forged in one piece with the camshaft itself. While Fig. 5 shows 
all the details of the valves and valve gear of an L-head motor, it 
must be borne in mind that every manufacturer has his own 
designs and standards. For example, in most motors a cam fol- 
lower is introduced between the valve push rod and the cam in 
order to minimize the friction. This usually takes the form of a 
fork which is in a guide of its own and has at its lower end a 
roller which rides on the face of the cam. 

The inner end of the camshaft carries a gear known as the 
timing gear in that its position with relation to the smaller gear 
on the crankshaft, from which it is driven, determines the time at 
which all the valves open and close. In a T-head motor there are 
two camshafts and two timing gears, and there are also usually 
additional gears for driving the circulating pump and the magneto, 

1. 29 



20 GASOLINE TRACTORS 



J 
J 






£ § 



3 



30 



Digitized by VjOOQIC 



GASOLINE TRACTORS 21 

which make the timing-gear end of the average motor look very 
complicated to the layman. In the motor shown in Fig. 5 there is 
but a single timing gear, and it also carries the ignition timing 
cam which determines the occurrence of the ignition spark in the 
different cylinders. This is marked Comm. Roller on the illustra- 
tion. Just below the timing cam will also be noted zero marks on 
the time gears; these are check marks to enable the gears to be 
reassembled in the proper relation after a motor has been taken 
down for repairs. The gear on the crankshaft is but half the size 
of the camshaft gear since each cylinder has but one power stroke 
for every two revolutions. There are two power strokes per 
revolution in a four-cylinder motor, and the camshaft must 
accordingly be driven at half the speed of the crankshaft in such a 
motor. 

Timing Valves. In a motor making 1000 r.p.m. (revolutions 
per minute), 2000 strokes or reciprocating movements of the 
pistons must take place in sixty seconds, so that the entire time 
consumed in making each stroke at this speed is three-hundredths 
second. A full realization of what an exceedingly short period 
this is in which to perform any mechanical operation should make 
it unnecessary to emphasize either the need for accurately timed 
valves to ensure an efficient running motor or the necessity of 
closely watching all parts of the valve gear to take up any lost 
motion caused by wear, since very little slack is required to cut 
down the effective opening of the valve. For example, assume 
the maximum lift of the valve from its seat to be \ inch plus the 
clearance of ts inch provided between the valve stem and the 
tappet to permit the valve to seat positively. Then if wear or 
lack of adjustment be permitted to increase this clearance to ^ 
inch, the valve can only lift ^r inch, so that the effective opening 
is reduced 12^ per cent for every thirty-second of an inch lost 
motion between the valve tappet and the valve stem. 

It is nothing unusual to see automobiles brought to the 
repair shop with so much clearance between their valve tappets 
and stems that the valves barely leave their seats when the cams 
come around. A tractor motor would not be of much service in 
this condition si/ive it would not develop enough power to carry 
its load. If it were not for the fact that usually in driving an 



31 



22 GASOLINE TRACTORS 

automobile only a very small fraction of its power is used it 
would be impossible to keep a motor running after it gets in such 
a condition. A knowledge of the principles of automobile opera- 
tion will be an aid to the tractor operator but he will do well not 
to attempt to apply them literally to tractor handling since they 
fall far short of what is needed to keep a tractor running. 

In designing a motor, both the contour, or outline, to be 
given the cams and their position on the camshaft are fixed, and 
the finished camshaft is a single piece of steel the cam faces of. 
which have been ground to a high degree of precision. In timing 
a motor, it is accordingly only necessary to time the valves of 
one cylinder as the others must of necessity also be correct. This 
process is made very simple on the Fordson motor, since it is 
accomplished merely by the correct meshing of the timing gears. 
When the two zero marks on the driving and the driven gear 
coincide the camshaft is in the proper position to open the valves 
of all the cylinders in the correct , order. This, of course, has 
nothing to do with the proper adjustment of the tappet clearance, 
which must be looked after at each valve. 

Checking Valve Timing. A closer check is usually considered 
necessary than is afforded by the meshing of the timing gears 
just mentioned, and to provide this, the necessary data is marked 
on the flywheel of the motor while a reference point is also marked 
on the crankcase, Fig. 6. In the illustration, the line U.D.C. 1 
and 4 shown on the rim of the flywheel opposite the reference 
mrka on the crankcase indicates that that point represents upper 
dead center for the pistons of cylinders 1 and 4. The line E.O. 
2 and 3 indicates that when that line on the rim coincides with 
the reference mark, the exhaust valves of cylinders 2 and 3 open. 
Similarly, E.C. 1 and 4 and 1.0. 1 and 4 represent, respectively, 
the exhaust closing and inlet opening points of cylinders' 1 and 4, 
while LC. 2 and 8 gives the inlet closing point for cylinders 2 and 3. 
The rest of the points for the various cylinders are not shown. 

Lead and Lag of Valve Movement. While the strong spring 
brings the valve down on its seat with a snap the moment the 
valve tappet rides off the cam, the valve cannot be opened in 
this manner. It must be lifted against the force of the spring, 
and as the time available for both its lifting and its closing again 

32 



GASOLINE TRACTORS 



23 



is so very short, it must begin to open somewhat before the 
moment when it is to be fully open. This lead is given to the 
inlet valves to a degree dependent upon the speed of the motor in 
order that a full charge of fuel mixture may be drawn into the 
cylinder on the intake stroke. 

It is possible to start the opening of the inlet valve on the 
suction stroke before the exhaust valve has closed because of the 
fact that a gas, as well as a solid body, has inertia. Inertia is 
that property of all matter 
that tends to resist a change 
of state, whether that state 
be rest or movement. If a 
man runs full speed down 
a hallway and a door at 
the other end is suddenly 
closed, he crashes into the 
door because he cannot 
overcome his own inertia 
in time to stop. On the 
other hand, if, when stand- 
ing quietly at the roadside, 
he attempts to board an 
automobile passing at 
twenty miles an hour simply 
by grasping the part nearest 
to him, the consequences 
are apt to be extremely 
unpleasant if his hold is 
good. If it is not good, 
he stays pretty much in the same place although his arm gets 
a severe wrench. In the same manner a gas possesses inertia, 
varying with its weight and velocity, or lack of it. 

When the gas is flowing out through the exhaust valve at a 
high rate of speed, since it has had almost the entire exhaust 
stroke in which to accelerate, the opening of the intake valve 
has no effect on its movement. Nor is there any risk of the 
incoming fresh charge passing through the cylinder and out the 
exhaust valve because its inertia makes it as hard to start as 




Fig. 6. Reference Marks for Valve Timing 



33 



Digitized by 



Google 



24 GASOLINE TRACTORS 

the high-speed exhaust is to stop and it cannot attain any speed 
until the piston is well down on the suction stroke. Then it in turn 
is hard to stop, so that it is possible to hold the inlet valve open 
after the piston has actually passed the lower dead center and 
started upward on the compression stroke. This delay is termed 
the lag given the valve closing, and in the case of the inlet valve 
it insures filling the cylinder with the fresh charge to the maxi- 
mum extent as the fresh gas is rushing in at its highest speed just 
at that moment; and every fraction of a second, or of an inch on 
the stroke, that the valve can be kept open, the more efficient 
the motor will be. 

Need of Closely Checking Valves. While not of the high- 
speed type as compared with automobile motors, which run up to 
2000 r.p.m. or over, many tractor motors are high-speed types for 
the service they are designed to render since the tractor runs at a 
very considerable fraction of its load most of the time it is work- 
ing while the automobile motor seldom carries over 20 per cent of 
its full load and then only for very brief periods.- Many tractor 
motors are designed to deliver their rated output at 1000 r.p.m., 
and that is high speed for a motor which must carry 80 per cent 
of its maximum load for eight to ten hours a day. Wear of small 
parts such as valve tappets is apt to be rapid in such service, so 
that to keep such a motor up to a good degree of efficiency, the 
valve timing must be carefully checked and valve tappet clear- 
ances adjusted to ^ inch at fairly frequent intervals. This is 
about the thickness of a visiting card. Some manufacturers sup- 
ply a small metal gage for the purpose of testing this clearance, 
and it should be used often since under the continued vibration 
and jolting of a tractor adjustments are apt to shake loose. 

Sixteen-Valve Engine. Particular attention has been called 
to the important influence that the rapid filling and emptying of 
the cylinders has on the efficiency of the motor, and mention has 
been made of the different expedients resorted to in order to 
increase this. The limit of efficiency in this respect is reached 
when single valves are used for the intake and the exhaust by 
placing both these valves directly in the cylinder head, so that 
neither the incoming nor the escaping gases have to go-round any 
bends in entering or leaving the cylinder, while the combustion 

34 Digitized by G00gle 



GASOLINE TRACTORS 25 

chamber of the latter is entirely free of pockets or dead spaces. 
To increase the efficiency still further, multiple valves are used, 
with the result that a larger effective area of opening is obtainable 
with a given cylinder head than, could be secured by increasing 
the diameter of the single valves to the. maximum permitted by 
that of the head. In other words, four valves are placed in the 
head with their centers located at the corners of a square, so that 
the greatest possible amount of space available in the circle repre- 
sented by the combustion chamber is utilized for valve openings. 
Two of these valves are used for the intake, while the other two 
are employed for the exhaust. 

Twin City Multiple-Valve Engine. In Fig. 7, which illustrates 
the Twin City tractor engine, the application of multiple valves 
to a valve-in-head type of motor is clearly shown. These valves 
have a clear diameter of 1? inches and are operated by overhead 
rocker arms, each arm carrying two valves. The part sectional 
view at the left shows the intake side of the motor, while the end 
sectional view at the right illustrates the complete valve operating 
gear of both the intake and the exhaust valves. 

Another unusual feature of this engine is the use of cylinder 
liners. The upper half of the crankcase and the cylinders them- 
selves are cast in a single block. The liner is made with a flange 
which rests on a ground seat in the cylinder, so that when the 
liner is inserted, the upper face of the flange is flush with the 
upper surface of the cylinder casting and the cylinder head, when 
bolted on, holds it in place. This construction is clearly shown 
in the right-hand cylinder in the side elevation. These liners 
form the entire cylinder wall, so that the pistons do not come in 
contact with the cylinder castings at any point. The dimensions 
of this motor are 4J by 6 inches, and it is governed to run at 
1000 r.p.m., at which speed it is rated at 20 hp. 

FUEL SUPPLY SYSTEM 

Operating Principle of Internal-Combustion Motor. The prin- 
ciple upon which the internal-combustion motor works is that of 
utilizing the great expansion of a volume of hydrocarbon vapor 
ignited when in intimate contact with a sufficient volume of 
oxygen to permit of extremely rapid combustion. In other words, 



35 



Digitized by VjOOQIC 



26 



GASOLINE TRACTORS 



an "explosion of gas," so to speak, is the driving force back of 
the piston. The various phases through which the gas passes in 
being drawn into the motor, compressed, fired, expanded, and 
exhausted have been referred to briefly in connection with the 
description of the four-cycle method of operation. Mention has 
also been made of the fact that the carburetor, while not strictly 
speaking a part of the motor proper, is a very important acces- 
sory. The purpose of the present section is to make clear how 
the fuel mixture of gas and air is obtained from the different 
liquid fuels employed. 




Fig. 7. Side and End Sectional Views of Twin City Sixteen-Valve Motor 
Courtesy of Minneapolis Steel and Machinery Company, Minneapolis, Minnesota 

Fuels Available. While there are a number of liquid hydro- 
carbons that may be employed as fuel in the motor, owing to 
their cost but very few of them are available for tractor opera- 
tion. It is scarcely necessary to discuss what may be done with 
benzol, or alcohol, or any one of a number of other fuels since 
their present cost is prohibitive. The choice of a fuel is limited 
to petroleum and its derivatives, gasoline, kerosene, and distillate. 
Owing to the great demand for gasoline for other purposes its 
cost has reached a point where the difference between it and 
the cost of kerosene is more than sufficient to offset the disad- 
vantages of the latter. Some farmers prefer to pay the higher 
price for gasoline because of the greater ease of operating the 



36 



Digitized by 



Google 



GASOLINE TRACTORS 27 

motor with this fuel, hut they are greatly in the minority, and 
their plowing operations are generally on a comparatively small scale. 

Petroleum as it comes from the ground is a heavy viscous 
liquid combining in one fluid practically the entire range of 
hydrocarbons (combinations of the gas hydrogen and carbon) all 
the way from that compound so light that it is evaporated by 
exposure to the atmosphere befpre the oil ever reaches the refinery 
to the heavy residue that is left after all the refining operations 
have been completed and that is suitable only for making arc-light 
carbons or for similar purposes. So far as their value as fuel for 
the internal-combustion motor is concerned, the only difference 
between any two of the hydrocarbons contained in petroleum lies 
in their evaporation points, that is, the temperatures at which 
the different liquids can be converted into vapor. The exceedingly 
volatile fraction that passes off into the air as an invisible vapor 
practically as soon as the oil is exposed to the atmosphere would 
make an ideal fuel; it would hardly be necessary to have a carbu- 
retor in its present form in order to handle such a fuel. But this 
highly volatile fraction forms such a very small percentage of the 
oil that running a motor on it would be equivalent to using per- 
fumery essence at a dollar an ounce for the same purpose. 

Products of Distillation. Up to within a few years ago the 
crude oil as it came from the well was subjected to a refining 
process which consisted chiefly of subjecting it to a gradually 
increasing range of temperatures so that the oil was broken up 
into its various constituent hydrocarbons, the latter being led off 
into separate vessels where the vapor was again condensed. For 
example, the first heat evaporated the naphtha, which was led off to 
its own condenser; then followed gasoline, which was in turn recon- 
verted into a liquid in another condenser and was itself followed 
by kerosene, light lubricating oil, heavy lubricating oil, and so on 
down the scale. This process of refining, however, produced but 
5 to 6 per cent of gasoline from the Pennsylvania and Ohio crude 
oil and so much less from the Texas and California oils that it 
was hardly worth while to attempt to make gasoline in this 
manner from them. 

The great demand for gasoline led to the improvement of the 
process by the distillation of the oil under pressure as well as at 

37 Digitized by G00gle 



28 GASOLINE TRACTORS 

a high temperature, so that in addition to the effect of the heat 
in breaking the heavy oil into its components, it was also actually 
"cracked" by the pressure and a much greater yield of the lighter 
fuel oils obtained. The Burton and the Rittmann are the two 
processes generally employed, and their products are sometimes 
referred to as "cracked oils. ,, These methods produce a fuel that 
commonly passes under the name of gasoline, but which, owing 
to the much greater proportion of heavier oil that it contains, is a 
low-grade fuel compared with the gasoline of ten years ago. 
Kerosene is the next product, and then follow the various grades 
of lubricating oil. 

Vaporizing Fuel. In order that a fuel may be used in the 
motor, it must first be converted into a vapor. The require- 
ments of this process depend entirely upon the character of the 
liquid to be handled. In the case of the very volatile gasoline of 
which there appeared to be an unlimited supply when the auto- 
mobile first appeared twenty-five years ago, it is only necessary 
to expose it to the air, so that the rudimentary carburetors 
employed on those first automobiles consisted in large part of a 
receptacle for a pool of gasoline over which the air was drawn to 
carburet it. This air picked up the vapor rising from the surface 
of the gasoline pool and with it formed an explosive mixture. 
The mixing process naturally could not be carried out with any 
speed, and it could not be depended upon to be uniform in its 
action. Gasoline evidently began to go down the scale very 
early, since the next step was to provide a heavy wick or similar 
surface to greatly increase the area exposed to the air current 
which was to be charged with the gasoline vapor. But gasoline 
of any grade that could be evaporated in this manner is now a 
thing of the past. 

Spraying Necessary. When a liquid is not sufficiently volatile 
to evaporate when the surface of a pool of it is exposed to the 
air, the first step in causing it to evaporate is to break it up into 
a large number of globules and thus vastly increase the amount 
of surface exposed to the air. To break a liquid up in this man- 
ner, it is sprayed by being forced through a small orifice known 
as a jet, or nozzle. The different types of carburetor jets, or 
nozzles, ordinarily employed are illustrated in principle by Fig. 8. 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 29 

The jet A is known as a fixed jet, in that it has no means of 
adjustment; B may be adjusted by means of the screw shown 
and is commonly referred to as a needle valve. A valve of this 
type is generally employed in the so-called mixers, which term is 
merely another name for a device that serves the purpose of the 
carburetor but is lacking in the refinements of construction of the 
automobile carburetor. Jet C is simply a variation of B in which 
the needle valve adjustment is made from above instead of below, 
while in D a cone takes the place of the needle but serves the 
same purpose, that is, so adjusting the orifice that the liquid will 
be broken up into a spray so fine as to be practically a mist. 
The fixed jet A, while used abroad to a greater extent than here, 
is now becoming more generally used in this country on account 
of its simplicity. 

The principle of all the types is identical, namely, drawing 
the liquid through a fine orifice, with or without a baffle surface 
in the form of a needle or cone, so that the liquid, being under 
pressure, is sprayed out of the opening as a fine mist. The suc- 
tion stroke, or descent of the piston in the first part of the cycle, 
supplies this pressure by decreasing the pressure in the cylinder 
so that the atmospheric pressure on the liquid in the carburetor 
forces it through the jet. 

Mixing Gas and Air. As it comes out of the jet, or spray 
nozzle, the fuel is in an intermediate stage between liquid and 
vapor. To convert it into the latter, the descending piston also 
draws up past the spray nozzle of the carburetor a supply of air. 
The latter is given a whirling motion by the shape of the chamber 
it enters, with the result that it picks up the tiny globules or 
drops of gasoline and breaks them up further. With the volatile 
gasoline of earlier days this was all that was required to produce 
a true vapor, but with the lower grade fuel now common, and 
particularly with kerosene and distillate, the addition of heat 
is necessary. It is absolutely essential that the fuel mist and the 
air be thoroughly mixed for the double purpose of converting the 
fuel into a vapor and of bringing every particle of this vapor 
into direct contact with an equivalent particle of oxygen in the 
air, since it is oxygen that makes the rapid combustion of the 
fuel mixture possible. 

39 Digitized by VjOOQI 



30 



GASOLINE TRACTORS 



Proportion of Air to Gas. Unless there is sufficient air, the 
result is a slow-burning, or over rich, mixture that produces a 
great deal of black smoke and causes the power of the engine to 
fall off. It also causes the familiar back fire that is so startling 
to the beginner. This occurs because the fuel is still burning in 
the cylinder when the inlet valve opens to admit a new charge 
and the latter is ignited and blown back through the carburetor 
instead of being taken into the cylinder. If there is too much 
air, the mixture is thin, or poor. In such a case the power falls 
off and the engine may miss in different cylinders, often jumping 
from one to another in an erratic manner. A back fire will also 
occur with a lean mixture since it is likewise slow-burning. 





Fig. 8. Types of Carburetor Noszles or Jeta 

To produce an explosive mixture requires the mixture of 
approximately ten to fourteen parts by volume of air to one of 
fuel vapor, the proportions naturally varying with the character 
of the fuel itself. But to produce an efficient explosive mixture 
in a given engine requires a carburetor that has either been spe- 
cially designed for that particular motor or one that has been 
adjusted especially with a view to meeting the conditions imposed 
by that motor. 

The amount of air needed for any given fuel or for any motor 
also varies largely with atmospheric conditions at the time and 
place in question. It is solely the oxygen content of the air that 
is of value in helping to burn the fuel mixture rapidly, and at 
times the air is denser than at others. The denser it is, the more 
oxygen it contains and the less of it is required to form a good 
explosive mixture. Just after sundown in spring and fall the air 
cools off very rapidly, and an automobile engine will run noticeably 



40 



Digitized by 



Google 



GASOLINE TRACTORS 31 

better at that time than in any other part of the clay and for the 
same fuel consumption the amount of air used can be decreased. 
The contrary is true of high mountain districts where, owing to 
the altitude, the air is thinner and contains considerably less 
oxygen per cubic foot than at the sea level. In climbing from sea 
level to a height of several thousand feet, it is necessary to allow a 
greater proportion of air to maintain the given amount of oxygen 
required for the efficient combustion of the fuel. A tractor engine 
in Colorado would accordingly require a great deal more air to 
operate efficiently than would one working in Illinois, the same 
carburetor and the same fuel being used in both cases. 

Details of Spraying Process. Since the difference between the 
pressure in the interior of the cylinder when the piston is going 
down on the suction stroke and that of the atmosphere (14.7 
pounds per square inch at sea level) is not very great at the 
beginning of the stroke and as the time interval for charging the 
cylinder is very short, the spraying of the fuel into the incoming 
air must begin immediately. This is accomplished by carrying a 
small supply of the liquid fuel in- the float chamber of the carbu- 
retor. A typical carburetor float chamber is illustrated at the left 
of Fig. 9, which shows a simple form of carburetor in section. 
The fuel enters from below through a needle valve, the needle of 
which passes through the hollow copper float. As the liquid rises 
in this chamber, the float rises with it and in so doing forces the 
needle down into its seat by means of the small weighted levers 
shown. The levers are attached to a collar on the spindle of the 
needle. 

It will be noted that this float chamber communicates with 
the spray nozzle located in the mixing chamber just to the right of 
it. As a liquid always seeks its own level, the fuel rises to the 
same height in the spray nozzle as it does in the float chamber 
and the float is set to close the needle valve at a point where 
this fuel level is normally but a small fraction of an inch below 
the opening of the nozzle. The liquid is accordingly sprayed 
out of the nozzle under the influence of a difference in pres- 
sure of less than 1 pound to the square inch; that is, as soon 
as the pressure above the nozzle due to the suction stroke of the 
piston becomes less than that of the atmosphere on the supply 

41 



32 GASOJJNE TRACTORS 

of fuel in the float chamber, the liquid is forced out of the small 
opening. 

This spray, or mist, is then carried upward through the car- 
buretor and through the inlet valve into the cylinder by the cur- 
rent of air drawn in at the opening below the spray nozzle and 
extending to the right. Owing to the peculiar form given the 
chamber surrounding the spray nozzle (known as a Venturi tube), 
a whirling motion is imparted to the incoming air and its velocity 
is increased. The result is to mix the spray and air more thor- 
oughly and to convert the mixture more nearly into a true vapor. 

Effect of Increasing Speed. It is apparent that as the speed 
of the motor increases, the suction on the spray nozzle will become 
greater, and the interval between suction strokes, particularly in a 
motor having four or more cylinders, will be so short that the 
spraying action will be practically continuous. This tends to upset 
the balance of the mixture by causing an excess of the fuel spray 
so that the proper proportion of fuel to air is no longer main- 
tained and the power output of the motor suffers correspondingly. 
To overcome this, means for supplying additional air are provided, 
usually in the form of an auxiliary air valve designed to be 
operated by the difference in pressure between the inside and the 
outside of the carburetor. In Fig. 9 an auxiliary air valve of this 
kind is shown in the upper part of the illustration. It consists of 
an opening in the carburetor body covered by a diaphragm, or 
plate, tbe latter normally keeping the opening closed by means of 
the spring shown. As the pressure inside the carburetor decreases 
below a certain point owing to the increasing speed of the motor, 
the atmospheric pressure on this diaphragm overcomes the spring 
and allows an additional supply of air to enter and combine with 
the mixture, which then passes off, through the opening shown at 
the right, to the intake manifold. 

The carburetor shown in Fig. 9 is a single fixed-jet type with a 
simple auxiliary air valve, and it serves to illustrate the principles 
upon which practically all carburetors work, namely, spraying the 
liquid fuel in the form of a fine mist into an incoming current of 
air to which greater movement and increased velocity are imparted 
as it passes the spray nozzle. There are a great many different 
types of carburetors and an even greater number of different 



42 Digitized by CjOOQ 






jl 



I 



Digitized by VjOOQIC 



- D i g i tized by Cj(J )C 



p • 

2-5 






Digitized by VjOOQIC 



i 



8 



Digitized by VjOOQIC 



GASOLINE TRACTORS 



33 



makes, but all operate on these basic principles. In some instances 
two or more nozzles are used, the smaller being in action only 
while the motor is idling and the larger increasing the supply of 
fuel when the increased speed of the motor brings a greater pres- 




Fig. 9. Section of Typical Fixed-Jet Carburetor 

sure to bear and causes them to spray. In this case the principle 
is that of altering the amount of fuel in the mixture in accordance 
with the speed, the air intake to the carburetor remaining fixed at 
all times, while in the single-jet type described above the air sup- 
ply is increased with increasing speed. Still other types increase 
both the fuel and the air supply, a needle valve on the jet being 



43 



Digitized by 



Google 



34 GASOLINE TRACTORS 

connected with the auxiliary air valve, as in the Schebler carbu- 
retor shown in Fig. 10. The needle valve, or spray nozzle, is at E, 
and the needle is attached to a bell-crank lever, indicated by the 
dotted lines, which is attached at its other end to the spindle of 
the auxiliary air valve A. As the auxiliary air valve opens down- 
ward under the additional suction of increased motor speed, it 
lifts the needle E and permits a greater amount of fuel to spray 
through the jet at the same time that an increased supply of air 
enters through the valve A. While it is automatic in its action, 
this carburetor is also provided with a hand control, the connecting 
rod of which is attached at B. The movement of this adjustment 
is limited by the boss D coming against the stop C. When in this 
position, it is set for running and corresponds to the mark AIR, 
indicating that the full air supply is being given; at the other end 
the adjustment quadrant is marked GAS. This adjustment is 
used chiefly for starting. In this particular carburetor the float, 
which is not indicated in the illustration, surrounds the spray 
nozzle and consists of a shellacked cork ring. 

Heating Requirements. The process of converting a liquid 
into a vapor is one in which considerable heat is rapidly absorbed 
from the surrounding air, so that the temperature of the resulting 
vapor is lowered. With the highly volatile gasoline used in early 
days no artificial heat was necessary to offset this under summer 
conditions, and the simple carburetors then in use were not pro- 
vided with any heating devices. But when the car was run in 
cold weather, it was nothing unusual for the carburetor to become 
choked up with snow and ice caused by this refrigerating action of 
evaporation, and this also happened when aeroplanes first reached 
high levels. The lower the grade of fuel employed, the heavier it 
is and the higher its temperature of evaporation, so that heat is 
required even with gasoline fuel nowadays. Kerosene cannot be 
vaporized unless the temperature is raised very considerably above 
that of the surrounding atmosphere even on a hot summer day, 
since this fuel is not at all volatile and will not evaporate at any 
ordinary temperature. 

Gasoline. For a carburetor handling gasoline only heat is 
ordinarily supplied by water-jacketing the mixture chamber, a 
small amount of hot water from the cooling system of the motor 



GASOLINE TRACTORS 



35 



being circulated around this part of the carburetor. The water- 
jacket space and connection of the fixed-jet type of carburetor will 
be noted in Fig. 9. In addition, the main supply of air to the 
carburetor is heated by clamping a sheet-iron box or "stove" 
about the exhaust manifold and passing the air over this heated 
surface before conducting it to the carburetor through a flexible 
metal tube of large diameter. 

Kerosene. While the arrangements mentioned work efficiently 
on the automobile using gasoline as a fuel, they would not prove 




Fig. 10. Interconnected Air and Fuel Feed 
Courtesy of Wheeler and Schebler, Indianapolis, Indiana 

satisfactory for burning kerosene. A very high temperature is 
required to vaporize kerosene and the method of applying it is 
illustrated by the section of the Wilcox-Bennett kerosene carbu- 
retor, Fig. 11. The float chamber is shown at the lower left hand, 
while the mixing chamber, just to the right of it, is equipped with 
two needle valves. The lower of these is designed to admit water, 
which is required in the majority of engines using kerosene as a 
fuel. The kerosene needle valve is just above the water valve, 
and it will be noted that the mixing chamber above this valye 
is surrounded by a cast-iron radiator provided with fins. The 



45 



Digitized by 



Google 



36 GASOLINE TRACTORS 

function of this radiator is to absorb heat from the air pass- 
ing over the exterior fins and to radiate it to the fuel mixture 
inside. 

The passage in which this radiator is located is connected 
directly with a damper in the exhaust outlet of the motor, so that 
the exhaust gases may be passed directly through it and used to 
warm the air instead of merely utilizing some of the heat of the 
manifold for this purpose as is done in a gasoline carburetor. In 
other words, all or part of the exhaust of the motor is used for 
heating by shunting it through the carburetor instead of allowing 
it to escape through the muffler in the usual way. The method of 
accomplishing this in the Wilcox-Bennett carburetor is shown in 
Fig. 12 which also illustrates the connection of the air cleaner to 
the carburetor. The details of the radiator itself and the needle 
valves are shown by the part sectional view, Fig. 13, which 
illustrates these essentials of the carburetor in the no-load position 
at the left and in the full-load position at the right. By compar- 
ing the sectional views with the illustration of the complete car- 
buretor, Fig. 14, a better idea of the relative positions of its 
essential parts can be had. 

At the right in Fig. 14 there is a horn-shaped device surround- 
ing the exhaust passage and connecting with the mixing chamber 
of the carburetor just below the needle valves. By referring to 
Fig. 11 or Fig. 13 again it is seen that the object of this device 
is to conduct heated air to the mixing chamber. This hot air is 
required when the motor is running slowly or under light load, as 
this represents a condition under which a kerosene burning motor 
will not ordinarily run satisfactorily since it is apt to cool off too 
much. The passage connecting this hot-air horn to the mixing 
chamber is designed to be opened and closed by a weighted valve, 
which is indicated in the drawing by heavy lines. It has already 
been explained that the suction of the motor varies with its speed 
and increases very markedly as the speed of the motor increases. 
At low speeds the force of gravity is more powerful than that of 
the motor suction, so that the weighted valve remains at the bot- 
tom and the hot-air passage stays open; when the motor speed 
increases sufficiently, the suction lifts this valve and holds it in a 
position to close the hot-air passage. 



Digitized by VjOOQ IC 



GASOLINE TRACTORS 37 

Air and Fuel Balanced. The Wilcox-Bennett kerosene carbu- 
retor is designed to be automatically controlled by the speed of the 
engine, the amount of fuel, air, and water admitted being depend- 
ent upon the suction, which varies almost directly as the speed. 



Fig. 11. Section of Wilcox-Bennett Kerosene Carburetor, Shown at Full Speed Position 
Courtesy of Wilcox- Bennett Carburetor Company, Minneapolis, Minnesota 

It will be noted that the auxiliary air intake and its valve are at 
the upper left hand and also that this diaphragm valve is directly 
interconnected with the kerosene needle valve in the spray nozzle. 
A stand pipe is employed instead of one of the conventional forms" 
of nozzle previously illustrated. The stand pipe consists of a tube 



47 



38 GASOLINE TRACTORS 

whose entire circumference is drilled with a large number of fine 
holes, through which the fuel is drawn instead of through a single 
opening at the top. The lines to the right and the left of the 
kerosene needle in Fig. 11 indicate that the fuel is issuing from 
these openings. In this illustration are shown the essential parts of 
the carburetor in the position they assume at full speed: the dia- 
phragm of the auxiliary air valve being depressed, so that therg is a 
flow of cool air into the carburetor at this point; the kerosene needle 
valve is lifted well off its seat to supply the maximum amount 



Fig. 12. Method of Employing Exhaust Gases in Wilcox-Bennett Carburetor 
Courtesy of Wilcox-Bennett Carburetor Company, Minneapolis, Minnesota 

of fuel; the hot-air intake below is closed; and the water intake, 
also governed by the weighted valve previously mentioned, is open. 
It must be borne in mind that under the conditions given the 
exhaust of the motor is at its maximum both in volume and tem- 
perature, so that the kerosene mist, immediately after issuing 
from the standpipe and being whirled into the radiator chamber 
by the multi-bladed fan shown in Fig. 13, is at once Subjected to a 
degree of heat reaching at times as high as 900° F. Since this is 
too hot for efficient combustion, before passing into the cylinder, 
the temperature of the fuel is lowered somewhat by the addition of 
the volume of air entering through the auxiliary air valve. The 
.admission of water and its admixture with the fuel vapor in the 
form of steam serves to provide additional cooling, the necessity 
for which will depend upon the action of the motor. 



** Digitized by G00gle 



GASOLINE TRACTORS 



39 



Gasoline and Kerosene Carburetor. Since kerosene will not 
vaporize at ordinary temperatures, it is necessary to use gasoline 
for starting, the motor being run on this long enough to warm up 
sufficiently to permit the use of kerosene. The combination gaso- 
line and kerosene vaporizer used on the Fordson tractor is illus- 
trated in Fig. 15. Being designed especially for use on this one 
machine, it has been made much more compact than types which 
must be adapted to a number of different motors. Compactness 





1 Fig. 13. Detail of Radiator, Wilcox-Bennett Carburetor 

Courtesy of Wilcox-Bennett Carburetor Company, Minneapolis, Minnesota 

has been obtained by combining the heating unit directly with the 
exhaust manifold, a shunt valve being provided to by-pass the hot 
gases as required. ' 

The kerosene carburetor itself is shown at the lower left. It 
is of the conventional single-jet type, except that instead of being 
designed to produce a working fuel mixture in the carburetor 
proper it is only intended to make a heavy kerosene mist, with 
the result that only a small amount of air is drawn through it 
from the primary air tube. As shown by the black arrows inside 



4? 



Digitized by 



Google 



40 



GASOLINE TRACTORS 



the small white tube, Fig. 15, this rich mixture of kerosene and air 
is drawn through a heating coil in a chamber provided for that 
purpose in the exhaust manifold. From that point it passes to a 
mixing chamber above the inlet manifold, in which it is diluted to 
the proper consistency by the addition of air through the auxiliary 
air valve shown at the top of the illustration. This air valve is 
controlled in the usual way, that is, it varies its position with the 
speed of the motor itself. 

Just below the mixing chamber are located the gasoline con- 
nection and passage, which are placed at this point since no heat 

is necessary for starting on gaso- 
line and since the gasoline spray 
is converted into a fuel mixture 
in the same mixing chamber that 
is used for the kerosene. The 
gasoline vaporizing device is 
only in use for a minute or two 
when starting, the gasoline then 
being shut off. While gasoline 
is being used, the exhaust shunt 
lever is moved to the ON posi- 
tion, which permits all the 
exhaust gases to pass through 
the vapor-heating tube and gives 
the maximum heating effect. 
After the motor has been running 
on kerosene for a short time, 
the shunt lever is adjusted to 
suit the load conditions, the 
temperature of the mixture being 
lowered if the lever is moved toward the OFF position. When it 
is desired to run any motor idle on kerosene longer than momen- 
tarily, it is necessary to supply the maximum amount of heat and 
the ignition should also be retarded, as otherwise the plugs are 
apt to become badly sooted. No provision is made for supplying 
water directly with the fuel on the Fordson, but an air washer 
is used which serves the same purpose by moistening the main air 
supply. 



Fig. 14. Assembled View, Wilcox-Bennett 

Carburetor 
Courtesy of Wilcox- Bennett Carburetor Com- 
pany, Minneapolis, Minnesota 



50 



Digitized by 



Google 



GASOLINE TRACTORS 41 

Need for Cleaning Air. About fifteen years ago, when the 
automobile first began to assume such a degree of reliability 
where its ignition and carburetion mechanisms were concerned as 
to permit some degree of attention being given to ailments of 
other parts of the motor, carbon deposits were discovered on the 
pistons and in the combustion chamber. Ever since then there 
has been a great deal of discussion as to the conditions which 
cause these deposits and the methods of preventing them. A 
great deal of the discussion and most of the methods adopted 
have been misguided, if not entirely futile, since an analysis of 
these deposits made at an early day proved them to consist of 
road dirt and grit to the extent of 65 per cent or more, the bal- 
ance being simply burned and partly burned lubricating oil, which 
serves as a binder and causes the mass to adhere to the cylinder 
head or piston. In addition to giving rise to these troublesome 
carbon deposits, which frequently accumulate to such an extent 
that they cause pounding or even preignition, the fine grit which 
composes a large part of the dirt drawn through the carburetor 
also causes the pistons and cylinders to wear very much more 
rapidly than they would were the air free of this foreign matter. 
Notwithstanding these discoveries, none of the numerous remedies 
proposed has ever taken the preventive form of cleaning the air 
before it is used. 

Tractor Air Conditions Very Bad. There are several reasons 
why the troubles caused by dirt in the air have not assumed such 
proportions on the automobile that it has been considered neces- 
sary to use a preventive. Chief among these is the great improve- 
ment that has taken place in many thousands of miles of American 
roads, which have been made dustless in recent years. The general 
recourse to heated air taken from a small box, or stove, placed 
around a part of the exhaust manifold is another reason of equal 
importance, since this prevents the direct entrance to the carbu- 
retor of the air passing through the radiator. Before reaching the 
opening of the hot-air box on the exhaust manifold it must pass 
around various curves and strike different obstructions, which 
cause most of the heavier particles of dust to fall. Since the high 
speed of the machine permits it to run away from its own dust 
very effectively, it is only on very windy days, when the atmos- 

Digitized by VjOOQ IC 



42 GASOLINE TRACTORS 

phere is generally dust laden, that more than a very small amount 
finds its way through the radiator. 

None of these advantages obtain in the case of tractor opera- 
tion. Plowing must frequently be carried out under very dusty 
conditions, with the result that the entire machine operates in the 
midst of a cloud of dust from which it cannot escape. Under 
such conditions a large amount of dust and grit is drawn into the 
carburetor as the suction is very heavy owing to the motor operat- 
ing under full load most of the time. Unless this intake of dirt is 



Fig. 15. Holley Combination Gasoline and Kerosene Carburetor as Used on the Fordson Tractor 
Courtesy of Henry Ford and Son, Inc., Dearborn, Michigan 

guarded against, wear of the moving parts of the motor becomes 
excessive. 

Since, as previously mentioned, approximately fourteen parts 
by weight of air to each part of liquid fuel are required to make 
an efficient burning mixture, the equivalent in volume of 10,000 
gallons of air is needed for every gallon of fuel. In the case of a 
tractor burning 20 gallons of fuel in a day's work, a volume of air 
equal to 200,000 gallons must pass through the carburetor and 
cylinders in ten hours. The amount of dust that such a great 
volume of air can hold in suspension under the conditions of 

Digitized by VjOOQ 1C 



GASOLINE TRACTORS 43 

tractor operation makes the importance of thoroughly cleaning the 
air too apparent to call for any emphasis. 

Types of Air Cleaners. Air-Washer Type. It is apparent 
that two or three different principles may be taken advantage of 
to remove dust and grit in suspension from a moving mass of air. 
The first of these to suggest itself is that of actually washing the 
air by passing it through a body of water, and a number of air 
cleaners are based on this idea. The action of the air in passing 
up through the water is indicated in Fig. 16, and it will be noted 
that in addition to dropping its dust and other foreign matter the 
air carries with it quite a percentage of moisture, so that the 
washing" process is a further advantage in those motors that require 
considerable water to insure cool running when burning kerosene. 
When using gasoline, however, washing the air is apt to he quite 
the contrary since the excessive amount of water tends to cool the 
mixture too much to permit efficient operation. The air washer 
employed on the Fordson tractor is shown in section in Fig. 17. 
It consists of a water tank with a central intake tube and an air 
guide mounted on a float and surrounding the intake tube. The 
suction of the motor serves to draw air into the washer, and it is 
then deflected downward into the water by the air guide. In 
order that the air may pass through a considerable depth of water, 
the air guide is attached to the float shown so that the air will 
always enter the water at the same distance below the water level. 
The float keeps this distance constant by maintaining the outlet 
of the air guide at the same point at all times regardless of the 
amount of water in the bowl. The air guide mentioned also 
serves another purpose in that it serves to cut off the air supply 
when the water supply is allowed to fall so low 'that the float 
rests on the bottom of the bowl. 

Centrifugal Type. Mention has already been made of the faet 
that in compelling the current of air drawn through the radiator 
of an automobile to pass around several obstructions most of the 
heavier grit is allowed to drop before the air can reach the carbu- 
retor intake. By purposely giving the current of air a whirling 
movement this effect can be accentuated by. taking advantage of 
centrifugal force to throw the particles of dust to the outer edge 
of the container, where they drop into a receptacle. This is the 

53 



44 



GASOLINE TRACTORS 



principle upon which the air cleaner shown in Fig. 18 is based. 
By referring to the phantom view of the same air cleaner, Fig. 19, 
it is seen that after entering, the air is conducted through curved 
channels, from which it issues to again strike a large central cone, 
thus acquiring a whirling motion which tends to deposit on the 
sides of the cone all matter in suspension that is heavier than air. 

This matter then gravitates 
down the sides of the cone and 
finally drops off the edge into 
the glass receptacle placed 
below, which permits the oper- 
ator to note the accumulation 
of dust and remove it in good 
season. 

The same principle is 

also employed in connection 

with a receiving vessel, or 

dust collector, containing 

water. An air cleaner of this 

type is shown in Fig. 20, and 

a sectional view in Fig. 21. 

In the latter illustration the 

action of the air currents in 

entering and striking the 

central cone is more clearly 

indicated by the arrows. The 

air is first drawn into the 

outer casing and the spiral 

tubes at A. These tubes are 

set on the inner circumference 

of the casing, so that the 

action of the air causes the 

water to whirl rapidly and assume the position indicated by the 

dotted line, exactly as any liquid will do in a bowl when stirred in 

one direction very rapidly. The water, on striking against the 

lower projecting edges of the spiral tubes, is broken up into a fine 

spray through which the air passes in being cleaned. The washed 

air then rises and enters the opening C of the inner cleaner, where 



Fig. 16. Sectional View of Parrett Wet-Type 

Air Cleaner 

Courtesy of Parrett Tractor Company, 

Chicago Heights, Illinois 



54 



Digitized by 



Google 



GASOLINE TRACTORS 45 

it is again subjected to a violent whirling. This further tends to 
throw down any particles of dust or water which may have been 
carried along with the air, the accumulation of dust being deposited 
at the bottom of the tube B. In a short time enough dirt col- 
lects to form a mud seal for this tube, so that if the operator for- 
gets to renew the water supply, the cleaner will continue to 
operate as a dry type. 

Felt Baffle Type. The third principle available in cleaning air 
is that of the dust screen, and the method of employing this is 
illustrated in Fig. 22, which shows the device in partial section. 
It consists of a cylinder of wire gauze on which felt is stretched. 
The air strikes this in entering, and the dust it contains is repelled 
by the felt while the air passes through and on to the carburetor 
by means of a connection with this inner chamber. The vibration 
of the motor as well as the force of the current of air itself tends 
to shake particles of dust off the felt and prevent their clogging it, 
the dust dropping out through the holes shown. In cold weather 
these holes may be closed to conserve the heat, and the dust then 
collects in the outer chamber until removed by hand. 

Attention Required. Regardless of the type of air cleaner 
employed, the chief attention required is the frequent removal of 
the accumulation of dust, or mud in case an air washer is used. 
Neglect of this precaution simply makes conditions very much 
worse than they would be were no air cleaner employed, since the 
accumulation of dirt in the cleaner is apt to be drawn directly 
into the motor. Where an air washer is employed, the deposit of 
mud is converted into dust very quickly by the heat of the motor, 
though the partial shutting off of the air supply causes the motor 
to miss and lose power, thus providing a warning of the lack of 
water. 

LUBRICATING SYSTEM 

Effect of Temperature and Pressure. Where the lubricating, 
system is concerned, as well as regards other essentials, the novice 
in tractor operation will do well not to rely on his automobile 
experience to carry him through without a slip that will result in 
serious damage. There can be no comparison whatever between 
the 30-hp. automobile motor that runs for ten hours a day and is 
seldom called upon to deliver 50 per cent of its rated power and 

55 L. 



46 



GASOLINE TRACTORS 



O 
CO 

C 



a 
a 






< b 



O 3 

o o 



^ & £ J I 

< u. > u. CO 






h| 



g * 

00 



O °5 

o e 

U 

I 



56 



Digitized by 



Google 



GASOLINE TRACTORS 47 

the tractor engine of the same rating that is delivering 80 to 85 
per cent of its rated output all day long. 

The sole object of lubrication is^to prevent moving surfaces 
from coming into actual rubbing contact of metal to metal, in 
other words, to maintain a film of lubricant between the two 
surfaces on which they may actually 
be said to float, though the film 
itself may be only a few thou- 
sandths of an inch in thickness. 



Fig. 18. Wilcox-Bennett Fry-Type Fig. 19. View Showing Method of 

Air Cleaner Separating Dust from Air by Cen- 

Courtesy of Wilcox- Bennett Carbu- trifugal Force 

retor Company, Minneapolis, Courtesy of Wilcox-Bennett Carburetor 

Minnesota Company, Minneapolis, Minnesota 

The problem is accordingly the same in the automobile and the 
tractor engines, but the ease with which a film of lubricant may 
be maintained between "moving surfaces depends upon the sur- 
rounding temperature and the pressure under which the surfaces 
move in contact. When the temperature of the circulating water 
is seldom allowed to exceed 165° F., as in an automobile motor 
running under but a fraction of its maximum load, the vaporizing 
point of the lubricating oil is seldom reached. But in a tractor 
engine running for hours at close to its full load the circulating 
water is seldom much below the boiling point at sea level, 212° F., 
and the conditions of operation are such that every part of the 



Digitized by VjOOQ IC 



48 



GASOLINE TRACTORS 



engine is very much hotter than this. Under the heavy load the 
pressure between the piston and the cylinder wall is much greater, 
and the oil tends to squeeze out much more rapidly, so that it 
must be renewed with far greater frequency than is necessary in 
an automobile engine. 

Types of Lubricating Systems. Splash System. The earliest 
practical type of lubricating system used on the automobile engine 
was the splash system. The crankcase is filled with oil to a cer- 
tain level, and the big ends of the connecting rods dip into it and 
splash it all ov^r the interior of the motor. To keep up the sup- 







WATERS ^ - - H wT^*L_"LZ: 



Fig. 20. Wilcox-Bennett Wet Type 
Air-Cleaner 



Fig. 21. Method of Operation in Wilcox- 
Bennett Wet-Type Air Cleaner 
Courtesy of Wilcox- Bennett Carburetor Company, 
Minneapolis, Minnesota 



ply, 1 quart or more of oil is added at the beginning of a run, 
which results in having too much oil at the start and not enough 
at the finish. Moreover oil is not always oil so far as its lubricat- 
ing properties are concerned, since they are burned out of it by 
high temperature. Therefore after a few days' steady use the oil 
becomes practically useless, and only the extra quart or two added 
to keep up the level serves as lubricant. 

When the motor is run very cool, either with gasoline or ker- 
osene, a certain proportion of the fuel mixture is condensed in the 
cylinders and finds its way past the pistons into the crankcase, 
thus thinning the oil out and further reducing its lubricating 



58 



Digitized by 



Google 



GASOLINE TRACTORS 49 

value. This is particularly true of kerosene, which has the further 
disadvantage under such conditions of washing the film of oil off 
the sides of the cylinder walls as it gravitates to the crankcase. 
One instance is cited in which a manufacturer agreed to deliver a 
tractor under its own power, but after a few hours running so 
much kerosene found its way into the crankcase that the main 
bearings were burned out and the tractor had to be towed back to 
the shop for repairs before ever reaching its prospective owner. 
In another case that illustrates the fallacy of depending upon 
automobile precedents a factory man was called to the assistance 
of a farmer who reported that the 
bearings of his motor had burned out 
before the end of the first week's work. 
When asked what he had done to lubri- 
cate the motor, the farmer said that he 
had added oil as often as he did on his 
Ford. 

Modified Splash System. The simple 
splash system of lubrication is accord- 
ingly not practical on the tractor engine, 
though it is successfully employed on 
hundreds of thousands of automobile 
motors. A small percentage of the 
tractors now in use employ this system 
but as a rule it is improved 'by the 
addition of some means of constantly 
feeding fresh oil to the crankcase or 

of circulating it over the bearings Fig. 22. ^ e ^|J£Type Dry 
and depending only upon the over- 
flow from the latter to furnish splash lubrication. The cross- 
section of a Waukesha motor, Fig. 23, gives an excellent idea of 
how the dippers on the ends of the connecting rods distribute the 
oil to every part of the motor. Large receptacles over the main 
bearings are kept constantly filled, while the spray of oil thrown 
up reaches even to the valve stems. The crankcase is divided 
into compartments, as shown in Fig. 24, which illustration also 
shows the oil pan forming the bottom of the crankcase. The oil 
is raised by a small pump, forced through the wire gauze screen 

59 '"- Digitized by G00gle 



50 GASOLINE TRACTORS 



Fig. 23. Sectional End View of Waukesha Motor, Showing Operation and Interior Construction 
Courtesy of Waukesha Motor Company, Waukesha, Wisconsiri 



60 



Digitized by VjOOQ IC 



GASOLINE TRACTOBS 51 

S, and distributed to the different compartments of the bleeder 
tube, or pipe having openings A, B, C, and D. The overflow 
returns to the pump and is again distributed, so that this is what 



Fig. 24. Crank Case Oil Pan, Showing Compartments and Bleeder Tube 
Courtesy of Waukesha Motor Company, Waukesha, Wisconsin 



Fig. 25. Diagram of Combination Force-Feed and Splash Lubrication 
Courtesy of J. I. Case Plow Works, Racine, Wisconsin 

may be termed a circulating-splash system of oiling. A gage on 
the crankcase shows the level of the oil. In some systems of this 
kind the stroke of the oil pump is regulated to feed the oil slowly 
and it remains in the crankcase until consumed. 



Digitized by VjOOQ 1C 



52 GASOLINE TRACTORS 

Force-Feed Splash System. In the force-feed splash system 
reliance is not placed entirely upon the splash of oil in the crank- 
cage to reach all surfaces in need of lubrication, but a supply of 
oil is forced directly to the main bearings, camshaft bearings, and 
timing gears, and the overflow from these points is allowed to col- 
lect in the crankcase and serve for splash lubrication for the pistons, 
piston pins, connecting rods, and cams. Copper tubes are usually 
placed on the sides of the connecting rods to lead the oil to the piston 
pins, and in some cases this oil is also relied upon to lubricate the 



Fig. 26. Moline Circulating Pressure Force-Feed Lubrication 

cylinder walls, since it is forced out of the hollow pin on to the cyl- 
inder. An indicator in sight of the operator shows whether the 
oil is being supplied by the force feed. The partial section of the 
Case engine, Fig* 25, illustrates the details of a system of this type. 
Necessity for Discarding Used Oil. One of the chief draw- 
backs to all forms of splash systems of lubrication for the tractor 
is the difficulty of educating the farmer up to a realization of the 
saving that the constant renewal with fresh oil represents in 
repairs. Lubricating oil is the most expensive single item of sup- 



GASOLINE TRACTORS 53 

ply for the tractor, regarded solely from the standpoint of its cost 
per gallon, and the farmer dislikes to throw it away no matter 
how long it has been used. Some tractor manufacturers recom- 
mend that the crankcase be drained at the end of every day's 
work, washed out, and refilled with fresh oil. When oil has been 
used, its structure is broken dowQ by the high temperature. It is 
"cracked" — exactly as petroleum is in the pressure distillation 
process by which all petroleum fuels are produced nowadays — and 
it has lost its lubricating qualities. By taking a sample of oil 



Fig. 27. Combination Force-Feed and Splash Lubrication. Detroit Fourteen-Lead 

Chain-Driven Oiler 

Courtesy of Atdtman- Taylor Machinery Company, Mansfield, Ohio 

that has been used in the crankcase for several days and rubbing 
it between the fingers, the great difference between it and a sample 
of fresh oil will be noted. The average user does not like to 
drain the crankcase every day, and some practice the false econ- 
omy of draining it but once a season. It will be found much 
cheaper at the end of a season's work to have bought plenty of 
good lubricating oil and used it but once, than to attempt to 
economize by using it over and over 'again. Repairs always cost 
far more than oil. The used oil may be employed to lubricate other 
parts of some machines, such as the track of a caterpillar tractor. 

Digitized by VjOOQ IC 



54 GASOLINE TRACTORS 

Pressure-Circulated Lubrication. Following automobile prac- 
tice, some motors have the crankshaft drilled throughout its 
length and tubes connecting with this bore rising from the con- 
necting rod bearings, so that the pressure generated by the pump 
causes the oil to flow over these bearings constantly, the cylinder 
walls being lubricated by the overflow through the piston pins. 



Fig. 28. Force-Feed Oiler of Two-Cylinder Oil-Pull Engine 
Courtesy of Advance- Rumely Thresher Company, Inc., Laporte, Indiana 

In this system no dependence is placed on splash lubrication, and 
the connecting-rod big ends are not allowed to dip into the over- 
flow, as shown by the section of the Moline motor, Fig. 26. 

This system is also known as the dry-crankcase type in that 
the excess oil drops into a sump, or well, below the crankcase in 
which the pump is located, with the result that the entire supply 

Digitized by VjOOQ IC 



GASOLINE TRACTOES 55 

is constantly kept in circulation. More than one pump is some- 
times employed for this purpose, so that oil is drawn from differ- 
ent parts of the crankcase at the same time. The advantage of 
this method is that the location of the machine, as in climbing a 
hill, has no effect on the quantity of lubricating oil that reaches 
every part of the motor. 

Fresh-Oil System. A very considerable percentage of all the 
tractors now in use follow steam-engine practice in lubrication by 
feeding only as much oil as is required by each bearing, so that 



Pig. 29. Eccentric-Driven Force-Feed Oiler 
Courtesy of Hart-Parr Company, Charles City, Iowa 

the oil is consumed almost as fast as it is fed. This has the 
advantage of constantly renewing the lubricating film with fresh 
oil. To provide a factor of safety, however, the supply must 
actually be fed faster than it is used by the bearings in order that 
oil may accumulate in the crankcase, and unless this is drained off 
at frequent intervals, this system is open to the same objection as 
the ordinary splash system. 

The supply of fresh oil for a system of this type is carried in 
an external reservoir which also serves as the lubricator, in that it 
is fitted with a number of small plunger pumps, one for each lead, 



Digitized by VjOOQ IC 



56 GASOLINE TRACTORS 

or tube leading to the bearings. The lubricator is driven by a 
belt, chain, or rod (preferably the last named) from the camshaft 
of the motor, as shown in Fig. 27, which illustrates the Aultman- 
Taylor engine equipped with a fourteen-lead Detroit lubricator. 
Fig. 28 shows a similar lubricator on the Rumely two-cylinder 
motor, and Fig. 29 a Madison-Kipp lubricator on the Hart-Parr 
engine, an eccentric or crank and rod being employed to drive the 
lubricator pumps in both instances. 

Frequent Attention Necessary. On an automobile, it is noth- 
ing unusual for grease cups to go an entire season without being 
refilled, and during that time they have only been turned down 
once or twice. How radically different is the attention required 
by a tractor may be appreciated from the instructions for oiling 
an International tractor. When doing belt work, the grease cup 
on the pulley must be turned down every hour. There are eleven 
bearings on the fuel and water pumps, camshaft, front wheels, 
rear axle, and clutch that require turning down every two hours 
that the tractor is running. On another group of ten bearings the 
grease cups must be turned down twice a day, while three others 
must be turned down once a day. 

COOLING SYSTEM 

Heat Efficiency of Motors. While the thermal, or heat, 
efficiency of the tractor motor is high as compared with that of a 
steam engine, in which it is difficult to utilize more than 8 per 
cent of the available heat of the coal, it is an unfortunate fact 
that a very large part of the heat available in gasoline or kerosene 
must also be wasted since no method that will utilize more of it 
has yet been discovered. Considering the fuel value of the enter- 
ing charge as 100, about 40 per cent of this escapes through the 
exhaust valve at the end of the power stroke and during the suc- 
ceeding exhaust stroke. An additional 35 per cent that cannot be 
utilized to drive the piston by its expansion must be absorbed and 
quickly dissipated or it will soon overheat the motor and bind the 
pistons hard and fast in the cylinders. Thus only 25 per cent of 
the real value of the fuel is converted into power. These are 
simply average percentages which may be made poorer or better 
by the type of engine, some simple steam engines working in the 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 57 

open in cold weather and poorly protected not showing an effi- 
ciency to exceed 3 or 4 per cent, while a condensing Corliss type 



1.1 

a* 



E<5 
& - 



;? 



St 



unit would reach 17 per cent and a modern type Diesel oil engine 
35 per cent or better. 

Types of Cooling Circulation. To carry the great amount of 
excess heat away from the cylinder heads and exhaust valve ports 

67 



58 GASOLINE TRACTORS 

with sufficient rapidity to prevent these parts becoming over- 
heated, a body of cool water is kept in direct contact with them 
and is replaced by fresh water as quickly as it can absorb the heat. 
This water is contained- in the jackets — spaces cast in the cylinder 
walls and cylinder head for this purpose. The cool water is con- 
ducted to the lowest part of this water-jacket, passed up over the 
hottest parts of the cylinder, and then led to the radiator consisting 
of a bank or nest of tubes. These tubes are made of copper, 
which is an excellent conductor of heat as well as of electricity, 
and their cooling surface is greatly increased by surrounding them 
with thin copper fins which give up their heat to the air very 
readily. The movement of the water between the jackets and the 
radiator is termed the cooling circulation. 

Thermo-Syphon Circulation. The circulation of the water may 
be effected by the difference in the temperature of the water itself 
or may be brought about by forcing the water through the piping 
at high speed by a pump. The first method is known as thermo- 
syphon circulation and its operation is illustrated by the view of 
the cooling system of the Fordson tractor, Fig. 30. The radiator 
is shown in section, while the flow of water through the connecting 
pipes and the cylinder jackets and head is indicated by the arrows. 
After passing downward through the radiator, the water issuing 
at the bottom is considerably cooler than that at the top of the 
cylinder jackets, which has been absorbing its charge of heat. As 
water gets hotter, it expands and becomes lighter, so that it tends 
to rise. The water in the cylinder head jacket accordingly flows 
toward the radiator and is replaced by fresh water rising through 
the cylinder jackets. The hotter the water gets, the faster it 
flows, its movement being controlled entirely by the difference in 
temperature between the water entering and the water leaving the 
system at the coolest and hottest points. It will be noted in the 
illustration how short and direct the connections are and how 
large their diameter is as compared with the connections on a 
motor on which a pump is employed to provide forced circulation 
of the cooling water, Fig. 31. . 

Forced Circulation. On the majority of tractors a forced type 
of circulation is employed. In this type the water is moved around 
through the cylinder jackets and to the radiator ftpd back by 



.Google 



Digitized by VjOOQ I 



GASOLINE TRACTORS 59 

means of a centrifugal pump driven from the camshaft or one of 
the other auxiliary shafts of the motor. The body of water car- 
ried, the size of the cylinder jackets, and the diameter of the con- 
necting pipes may all be made much smaller than in systems 
where the water must move under the force of its own difference 
in temperature, as in the thermo-syphon system. But it is also 
apparent that the factor of safety is also somewhat lower in the 
forced circulation type than in the other. Any failure of the pump, 
fan, connections, or radiator must be detected and the engine 



Fig. 31. Pump and Connections of Forced-Circulation Cooling System Used 

on Heider Tractor Engine 

Courtesy of Rock Island Plow Company, Rock Island, Illinois 

stopped at once if serious damage is to be avoided. With an 
engine that is designed to be run constantly under such a high 
percentage of its maximum load for a number of hours as the 
tractor engine, the cooling and lubricating systems are of the 
greatest importance. This is true particularly of the cooling sys- 
tem since any failure in it involves the lubrication system as well, 
as the moment the temperature rises beyond control, the lubricating 
oil is burned to carbon and the damage is done. 

Protection of Radiator from Stresses. The tubular type of 
radiator is the most practical for tractor use owing to the neces- 



Digitized by VjOOQ 1C 



60 GASOLINE TRACTORS 

sity for withstanding constant vibration and also jolting and rack- 
ing, and it is good practice to support the radiator on a flexible 
mounting so that these stresses cannot affect it directly. This 
refers particularly to the straining and -racking due to the pas- 
sage of the tractor over very uneven surfaces. To prevent damage 
from this cause, some radiators are mounted on a pin and trun- 
nion, others have a three-point support, while still others are 
located at points on the frame where they will be subjected to the 
least stress from the twisting and bending due to rough going. 
In the illustrations in the section on motors the pumps and con- 
nections used on some of the machines are noticeable so that it is 
unnecessary to illustrate them here. 

Automobile Experience Misleading. When first undertaking 
the management of a tractor, the average operator is "very apt to 
be guided by his automobile experience and treat the heavier and 
slower-traveling machine in the same manner. This is apt to lead 
to serious errors as far as both the cooling and the lubrication are 
concerned. The tendency of most automobile engines is to run 
too cool to be efficient. In other words, if they could be run 
steadily at a higher temperature, less gasoline would be used and 
the smaller quantity passing through the cylinders would be 
employed more efficiently. But an automobile engine never runs 
steadily for any length of time and it is very seldom that more 
than a fraction of its normal power output is used at all. Except 
in pulling out of a mud hole or in climbing a very steep hill, it is 
rare for more than 25 per cent of the output of the motor to be 
needed in driving the car. Consequently its cooling system is very 
seldom called upon to work to capacity. 

There are few cars built that could climb a two- or three- 
mile hill mainly on second or even third speed without starting 
the water to boiling very violently, and if the hill were five miles 
long, few would be able to get up without a stop on the way to 
cool off the motor. Compared with the level road service that an 
automobile is usually called upon to perform, the tractor, par- 
ticularly when plowing, is performing the equivalent of mounting 
a steep hill on second or third, with the exception, however, that 
there is no summit to the hill and no opportunity to cool until the 
motor is shut down for the day. The cooling system accordingly 

70 



GASOLINE TRACTORS 61 

calls for close attention, any sign of overheating being noted 
immediately and the engine shut down at once to remedy the 
trouble. Fan belts and pumps must constantly be kept at a high 
state of efficiency since slippage at the fan or a leaky pump gland 
will reduce the cooling ability of the system all out of proportion 
to the apparent importance of the defect. When working under a 
heavy load, such as plowing or driving a good-sized thresher, the 
engine cannot be shut down too quickly upon the first indication 
of any trouble with the cooling system as under such conditions 
only a few minutes are required to destroy the film of lubricating 
oil between the pistons and cylinders and then the damage is done. 
With an automobile engine it is seldom necessary to add 
water to the cooling system even after a long run on a hot sum- 
mer's day. A tractor cooling system, on the other hand, may 
need water several times a day, and this is particularly true of the 
thermo-syphon type of circulation since the water will not con- 
tinue to circulate unless the entire system is filled to a certain 
level. The slower speed at which the water circulates in this type 
keeps it at a higher average temperature, so that evaporation is 
rapid. The manufacturers of the Fordson, for instance, recom- 
mend that the radiator always be filled before starting and replen- 
ished every time the machine is stopped for fuel or oil. As regards 
winter use, the same precautions apply as in the case of the auto- 
mobile, that is, the radiator must either be drained upon stopping 
the motor or an anti-freezing solution used. Since the latter 
reduces the boiling point considerably, evaporation is even more 
rapid when running under full load on anything but very cold 
days, so that it is better practice to drain the system. 

IGNITION SYSTEM 

Importance of Ignition. It has been previously stated that 
precedence cannot be given to any of the systems upon which the 
operation of the motor depends since the failure of any one means 
the stopping of the motor. It will be found in practical service, 
however, that there are various degrees of importance as far as the 
order in which the failure of these systems may be responsible for 
stopping the motor is concerned. Considered from this point of 
view, the ignition system heads the list in that it is apt to be the 



71 

' Digitized by 



Google 



62 GASOLINE TRACTORS 

cause of failure to operate more frequently than any of the others. 
There is no function of the motor, a knowledge of which is more 
important to the operator than familiarity with the principles 
involved in ignition, since without this knowledge it is always 
much more difficult to locate and remedy the trouble. Ignition 
breakdowns do not result in the serious damage that attends a 
failure of the cooling or the lubricating system, but they involve 
vexatious delays and the loss of much valuable time when the 
difficulty cannot be located quickly. The following brief review 
of electrical principles is confined wholly to those utilized in tractor 
operation, and they should be thoroughly mastered. 

Electrical Principles 

Electric Current. Electricity is one of nature's forces possess- 
ing many of the characteristics of light and heat plus a number 
that are peculiar to it alone. Like light and heat, it may be pro- 
duced by artificial means in a number of different ways. The 
energy it represents may be utilized in different forms, such as 
current or as magnetism. For ignition purposes the electric cur- 
rent is either produced by a direct-current generator and chemically 
converted into another form in a storage battery from which it is 
taken for producing the spark required, or it is generated by a 
magneto, which is a simple form of alternating-current generator. 
Electric current may thus be direct or alternating, and in either 
case it possesses the property of being able to flow along or in a 
conductor. In the former case it flows in one direction around 
what is termed a circuit, the point at which it issues from the 
generator or battery being known as the positive, or +, pole, and 
the one to which it returns being the negative, or — , pole. The 
signs + and — are usually stamped on storage batteries to indi- 
cate what is known as the polarity of the battery, and they cor- 
respond to the north and the south poles of a magnet. Alternating 
current, on the other hand, pulsates, or alternates, first in one 
direction and then in the opposite, so that a pole which is positive 
at the beginning of an alternation becomes negative at its comple- 
tion since the current then rises and flows in the opposite direction. 
A direct current is of uniform strength in addition to flowing in 
one direction, while an alternating current rises from zero to its 

' '•* ----- 72 Digitized by G00gle 



GASOLINE TRACTORS 63 

maximum and then drops back to zero to rise again in the opposite 
direction. The majority of tractors are equipped with magnetos, 
which generate an alternating current, and from the character of 
such a current, as just outlined, the importance of properly tim- 
ing the magneto to the engine may be appreciated since the cur- 
rent for producing the spark is only present when an alternation 
is approaching its maximum, or peak. If the magneto is improp- 
erly timed to the engine, no spark will occur at the plug. 

Electrical Units. Electricity may be measured in units 
equivalent to the pressure and the rate of flow of any other form 
of energy and, carrying out the comparison, it also encounters 
resistance to its flow. The ampere is the electrical unit of quan- 
tity; the volt, that of force, or pressure; and the ohm, that of 
resistance. The electrical power unit is the watt, equal to the 
product of 1 ampere times 1 volt. The flow of an electric current 
may be compared directly to that of water under pressure in a 
pipe. The number of gallons delivered per minute is the equiva- 
lent of the amperes of current; the pressure under which it is 
delivered corresponds to the voltage of the current; and the 
resistance to flow represented by the friction of the water against 
the walls of the pipe corresponds to the resistance encountered by 
the current in a wire or other conductor. By increasing the pres- 
sure on the water, a greater volume is delivered in a given time. 
By increasing the voltage of an electric current, although no 
greater volume of current is delivered, the resulting power is cor- 
respondingly greater since electrical energy is represented by the 
product of the number of amperes times the voltage. Moreover 
when the pressure on the water is increased, a smaller proportion 
of the total head, or pressure, is lost in friction, and this is equally 
true of an electric current since the higher the voltage, the smaller 
the amount of electrical energy dissipated in the wire as resistance. 

Conductors. The flow of an electric current is v determined by 
the nature of the material comprising what is known as the cir- 
cuit. Some materials are very good conductors, such as silver, 
copper, brass, and aluminum; others are poor conductors, such as 
iron, nickel, and alloys containing a high percentage of these metals; 
while still other materials, such as glass, porcelain, mica, rubber, 
wood, and stone, will not conduct the current at all when dry. • 

^— — _ _ 73 . [ litized byC 



64 GASOLINE TRACTORS 

The latter are insulators and are used to prevent the passage of 
the current where this is not desired; for example, part of the 
spark plug is made of porcelain. The ability of a material to 
conduct electric current is determined by its size as well as by its 
nature. Given two pieces of wire of the same size, one of copper 
and the other of iron, the copper wire will conduct the current 
approximately thirty times easier than the iron. By increasing 
the iron wire to thirty times the size of the copper wire, both will 
then conduct the same current and voltage with the same amount 
of resistance. Iron and nickel are accordingly high resistance 
conductors, preventing the free flow of the current and converting 
a large part of the energy represented by the latter into heat, 



Fig. 32. Simple Series Circuit Representing Ignition System of Single-Cylinder Motor. 
The Parallel Lines are Ground Return through the Motor 

which explains why a piece of iron wire will not serve as well for a 
magneto or battery connection as the copper wire supplied by the 
manufacturer. In addition to the insulators already mentioned, no 
fabric such as silk, cotton, and wool will pass current when dry, 
while dry air is the best insulator known. 

Circuits. It has already been mentioned that a current flows 
from the positive to the negative pole of the source of energy, but 
in order for it to do so there must be a complete circuit of con- 
ducting material between the two, a current of low voltage being 
considered in this connection. The presence of any insulators in 
the path of the current accordingly prevents its flow, and since air 
is one of the best insulators, any break in the current such as a 
parted wire or a loose connection admits air and interrupts the 

Digitized by VjOOQ IC 



BORING THREE-WHEEL TRACTOR WITH FORWARD DRIVE AND 
UNDERSLUNG PLOWS 



HEAVY THREE-WHEEL TYPE OF TRACTOR 



Digitized by VjOOQ IC 



Digitized by VjOOQIC 



GASOLINE TRACTORS 



65 



flow of current. If the material comprising the conducting path, 
or circuit, be of high resistance, the flow of current will be either 
greatly reduced or prevented altogether in the case of the low- 
tension currents employed in ignition. If a conductor of high 
resistance, such as a very small piece of wire, occurs in the circuit 
of a storage battery, it is likely to melt owing to the heat generated 
by its resistance. 

Ignition Circuits. Ignition circuits are of but one kind, that 
is, series circuits in which all the pieces of apparatus, such as the 
magneto, the coil, and the plugs, form successive steps through 
which all the current must pass in order to complete the circuit. 
Simple forms of series circuits are illustrated in Figs. 32 and 33, 
which show a dry battery, coil, and plug used as a starting system 



YTA 



r^ 



s 



O 



> 



Fig. 33. 



Series Circuit Using Low-Tension Magneto for 
Single-Cylinder Ignition System 



for a tractor and a low-tension magneto, coil, and plug constitut- 
ing a complete ignition system. When a battery is employed for 
lighting to carry on night work as well as for ignition, two inde- 
pendent series circuits may be fed from the same source, the 
amount of current taken by each being determined by the resist- 
ance that it presents to the flow of the current. A multiple, or 
parallel, circuit is one in which lamps, motors, or other apparatus 
may be inserted at any point, each unit being connected to oppo- 
site sides of the circuit, so that any unit may draw current inde- 
pendently of the others. Connections may be taken at any point 
on opposite sides of such a circuit to form a branch circuit and 
the apparatus in the branch circuit connected in series, resulting 
in what is termed a multiple-series circuit. 



75 



Digitized by 



Google 



66 GASOLINE TRACTORS 

Voltage and Amperage. The pressure under which the cur- 
rent flows is termed its voltage, and this may be determined 
either by the source of supply or by the presence of a transformer 
in the circuit. In the case of a battery the voltage depends upon 
the number of cells connected in series with one another, while the 
amperage, or volume of current, is measured by that of any one 
cell in the series. For example, dry cells deliver a current at 1£ 
volts and ordinarily average 15 amperes for short periods. A 
battery of four dry cells in series would thus produce a current of 
15 amperes at 6 volts. If the cells were connected in multiple, that 
is, all the positives together and all the negatives together, the 
current would be increased but the voltage would be that of a 
single cell, so that there would be a current of 60 amperes at 1| 
volts. 

Storage Battery. In the case of a storage battery which 
delivers current at 2 volts per cell, the voltage required for igni- 
tion, that is, 6 volts, is obtained by connecting three cells in 
series, while the volume of current depends upon the capacity of 
the individual cells in the series, and this in turn is measured by 
their size. For ignition service cells of a battery are always con- 
nected in series, so that the positive of one cell must be connected 
to the negative of the next, and so on throughout the series, one 
terminal of the battery being positive and the other negative. 
Any cross connection in the series, such as the connection of the 
positive of one cell to the positive of the next, would cause one 
part of the battery to act against the remainder, with the result 
that no current would be delivered to the outside circuit. 

Magneto. The voltage of the magneto or any other mechani- 
cal current-generating device is determined by the speed of its 
armature. The magneto illustrates the fact that electricity and 
magnetism are different forms of the same force in that one may 
be readily converted into the other. By moving a magnet close to 
a coil of wire, a current of electricity is induced in the wire, while 
if a coil of wire is placed about a bar of iron or steel and an 
electric current is then passed through the wire, the bar becomes 
magnetic. Steel retains a considerable percentage of the magne- 
tism after the current ceases and is termed a permanent magnet. 
The fields of a magneto are formed of permanent magnets and 



.Google 



Digitized by VjOOQI 



GASOLINE TRACTORS 67 

supply the magnetism by means of which a current is generated 
when the wire on the armature is moved pa$t their pole pieces, 
that is, their north and south poles. Therefore a magneto will 
generate a current at any speed, but the amount of current and 
the voltage under which it flows depend upon the speed with 
which the armature is revolved. The strength of a magnet is 
represented by imaginary lines passing from one pole to the other, 
and these are termed lines of force. The voltage of the magneto 
current is determined by the number of times per minute that, the 
wires of the armature cut through the lines of force between the 
magnet poles. 

Low- and High-Tension Currents. The foregoing brief expla- 
nation has been confined to what are known as low-voltage cur- 
rents, the storage battery delivering current at 6 volts for ignition, 
while the magneto when running at full speed generates current at 
approximately 100 to 125 volts. Any current under* 500 volts is 
usually referred to as a low-voltage current. In connection with 
the explanation of insulators it has been mentioned that the 
interposition of any insulating material in the circuit, and partic- 
ularly a break or loose connection which creates an air gap, 
interrupts the flow of current. This is true of all low-voltage 
currents; all parts of the circuit must be not merely connected but 
in firm and positive contact, and the contact surfaces must be 
clean and bright since dirt is likewise an insulator. This is a 
principle frequently overlooked in the care of tractor and farm 
engines, which usually work in very dusty places; it is absolutely 
necessary to keep all connections clean and tight to insure the 
satisfactory working of the ignition system. 

Since even a loose connection will interrupt the flow of current 
in a low-voltage circuit, it is not suitable for the production of a 
spark unless the terminals representing the positive and negative 
sides of the circuit are actually brought into contact and then 
separated. What is known as the low-tension system of ignition 
is employed on thousands of stationary farm engines and also on 
many tractors having low-speed engines. Most stationary engines 
are run at low speeds, ranging from 200 or less to 450 r.p.m., 
while few tractor engines run below 600 r.p.m. at normal speed 
and most of them operate at much higher speeds. 



77 'OOQl 



68 



GASOLIXE TRACTORS 



5** 




■0* 



X 



— fl - - I 



X 



=® 



&* 



■gr 



x 



* case 



Types of Ignition Systems 
Low-Tension Ignition. While dry cells may be employed for 
ignition with a stationary engine equipped with a hit-and-miss 

governor that cuts off the cur- 
rent except on the power strokes, 
they do not give satisfactory 
service and therefore a magneto 
is generally used. The magneto 
chosen is the simplest type and 
consists of nothing more than 
the field pieces, or permanent 
magnets, and a simple armature 
having a single winding. It 
may either be rotated or given 
a quick partial revolution by 
a rod and spring, but in any 
it must be timed to the 
engine, so that the current in 
its armature is at the maximum 
value when the spark is to occur 
in the cylinder. While such a 
magneto produces ample cur- 
rent at a fair voltage it is not 
sufficient to produce a spark of 
the desired size for low-tension 
ignition, and therefore a spark 
coil is placed in the circuit. 

Spark Coil. The spark coil 
consists of a single winding of 
many layers of heavy insulated 
wire on a thick short core built 
up of fine iron wire that has 
been annealed until it is very 
soft, as in this condition it is 
capable of being magnetized and 
demagnetized very quickly. Such a coil acts on the principle of self- 
induction and produces a much hotter and larger spark than the 
magneto could unaided. Its working will be clear from Fig. 34, 




78 



Digitized by 



Google 



GASOLINE TRACTORS 69 

which shows a typical low-tension ignition system. Up to the 
time it is necessary for the spark to occur in the cylinder, the 
ignitor has its points in contact, so that the circuit is closed and 
current flows through the ignitor and the winding of the spark 
coil. Consequently the core of the coil is magnetized and stores 
up the equivalent of the current which magnetized it. When the 
circuit is broken by the sudden snapping of the ignitor, this mag- 
netism is instantly reconverted into electric current and adds its 
force to that of the current in the winding, and a much hotter 
spark results at the contacts. In fact, this is really a flash instead 
of a spark and is usually termed an arc; and it is so hot that it 
burns the contact points away rapidly, which is one of the dis- 
advantages of the low-tension system. 

High-Tension Ignition. In high-tension ignition the ignitor of 
the low-tension system is replaced by a spark plug with fixed 
electrodes, or terminals, separated by an air gap. But in order 
that the current may bridge this gap, it is necessary to raise it 
to a high voltage. This ranges all the way from 10,000 to 30,000 
volts, the higher voltage being necessary when the initial com- 
pression of the engine is high since a greater electrical tension is 
required to create a spark across a gap in compressed air than 
out in the open. 

Induction Coil. In the brief reference given to elementary elec- 
trical principles it has been mentioned that when a coil of wire is 
passed before a magnet, a current of electricity is induced in the 
wire. This also occurs either when one coil of wire in circuit 
through which a current is flowing is moved close to another in 
which there is no current or, the two coils being stationary, 
when the current is suddenly broken in the first. This is the 
basic principle of the transformer, or induction coil. As in the 
case of the spark coil, the effect produced is greatly increased by 
using a heavy core of soft-iron wire. The character of the current 
induced in the second coil depends upon the relation that the 
windings of the latter bear to those of the coil in which the 
current, termed the primary current, is flowing. If both coils 
have the same number of turns in their windings, the induced, or 
secondary, current will be approximately the same in amperes and 
volts as the primary current. By increasing the number of turns 

Digitized by VjOOQ IC 



70 GASOLINE TRACTORS 

in the secondary winding of the coil, the voltage of the induced 
current will be increased correspondingly. An induction coil 
accordingly consists of a comparatively few turns of heavy wire 
for the primary winding, which is closer to, though insulated 
from, the soft-iron core. The secondary coil consists of a great 
number of turns of very fine wire and surrounds the primary 
winding, but it must also be well insulated from the latter, as 
otherwise the high tension-current would tend to jump from the 
windings of one to the other. A coil in which this has occurred 
is said to be punctured and, as it is short-circuited, is useless for 
ignition until repaired. 

Mechanisms to Make and Break Circuit. Where batteries 
are employed for ignition or the magneto generates a current 
which, though alternating in its nature, is of such high frequency 
as to be practically continuous, as on the Fordson tractor, the 
induction coil must be equipped with a vibrator to make and 
break the circuit since current is only induced in the secondary 
winding when the circuit is broken or the current rises and falls 
from zero to maximum and the reverse, as in an alternating 
current of lower frequency. In what is known as the modern 
battery system, employing a storage battery kept charged by a 
small direct-current generator, a primary contact breaker in con- 
nection with the distributor takes the place of the coil vibrator 
and but one coil is used. 

Essential Parts of System. A high-tension system accordingly 
consists of a source of current, most often a magneto, a coil, a 
spark plug for each cylinder, and a distributor. The distributor 
always forms a part of the magneto and is driven by the magneto 
shaft, and in what is known as the true high-tension type of 
magneto the coil is also incorporated with it; that is, the magneto 
generates the primary low-tension current and also transforms it 
or steps it up to the required high voltage, the armature usually 
carrying both the primary and the secondary windings. Conse- 
quently with a high-tension magneto the complete ignition system 
consists of the magneto itself, the spark plugs, and the necessary con- 
necting cables, so that the entire system is practically self-contained. 

Condenser. A part of the high-tension system with which the 
operator is not likely to become acquainted unless something goes 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 71 

wrong with it is the condenser. In the form employed for igni- 
tion the condenser consists of alternate leaves of tinfoil and par- 
affined paper, the latter serving to insulate the sheets of tinfoil 
from one another. The tinfoil sheets are divided into two groups, 
which are connected to opposite sides of the contact breaker of 
the magneto, so that the condenser is in multiple with the breaker. 
(Magneto parts and construction are explained in detail in con- 
nection with the description of some of the standard makes 
employed for tractor ignition.) When parts in contact carrying 
current are suddenly separated, a flash, or arc, occurs owing to 
the tendency of the current to continue its flow across the break, 
as happens in a low-tension ignitor. This not only represents a 
loss of energy but tends to burn away the parts. To prevent 
this, a condenser is shunted about the contact, that is, connected 
in multiple with it. The current, instead of continuing across the 
gap in the form of an arc as the contacts open, flows into the 
condenser, which has the capacity to store a charge of electricity. 
Immediately upon the contact being made again so as to reclose 
the circuit, this stored charge flows back from the condenser into 
the circuit. 

Safety Spark Gap. In the explanation of circuits men* on 
has been made of the fact that a current divides or flows thrc igh 
different branches of a circuit in proportion to the resistance in 
those branches. In other words, it will always seek the path of 
least resistance. Consequently, if the air gap of a spark plug be 
made so large that it represents a resistance greater than the 
insulation of the windings of the coil, whether this coil be sepa- 
rate or on the armature of the magneto, the current will break 
down the insulation and short circuit the winding. The current 
burns away the electrodes of the spark plugs and the gap must be 
adjusted from time to time to correct this; at the most the gap 
should not exceed the thickness of a visiting card, or ■$? inch. 
As the gap widens, the spark becomes thinner and loses its heat 
value so that the ignition is less and less satisfactory. When at 
last the gap becomes so wide as to present a greater resistance 
than the coil insulation, the spark will jump across the safety 
spark gap provided to protect the coils. This gap is designed 
with an opening having a resistance that is considerably lefcs than 

81 Digitized by G00gle 



72 GASOLINE TRACTORS 

that of the coil insulation so as to allow an ample margin of 
safety for the coils. It is usually located under the arch of the 
magnets of a high-tension magneto and is mounted on the dis- 
tributor of a modern battery ignition system. The occurrence of 
a spark across this gap is an indication that one or more of the 
spark plugs have been burned open too far, though this will 
usually be evident from the poor ignition resulting. 

Low-Tension Magneto. Magneto ignition has proved the 
most dependable as well as the most enduring for tractor work 
since the excessive vibration and jolting make the use of the 
storage battery practically out of the question. Dry cells are of 
little value in any case for ignition, except where starting is con- 
cerned, and the necessity for them has been eliminated by the 
development of the impulse starter on the magneto, as described 



Fig. 35. Inside and Outside Views of Low-Tension Ignition Plug 
~ Used on Oil-Pull Tractor 

later. There are several types of magnetos in general use on 
the tractor and a brief reference is made to each of them. 

On tractors employing low-speed horizontal engines, low- 
tension ignition is standard equipment. It has the advantage of 
being extremely simple and all its parts can be made amply strong 
enough to withstand the strenuous treatment of tractor service in 
the field. Its chief disadvantage is the more or less frequent 
necessity for attention to the ignitors, though the hot flash pro- 
duced by the latter is better adapted to ignite low-grade fuels 
than the high-tension spark produced by a plug. The magneto 
employed with the low-tension system has but one winding and 
no contact breaker nor distributor. It is connected in a simple 
series circuit with a spark coil and the ignitors. The Bosch low- 
tension' magneto is the type employed on the Rumely tractor. 



82 



Digitized by VjOOQIC 



GASOLINE TRACTORS 73 

In Fig. 35 ape given two views of an ignitor, the view at 
the left showing the tripping mechanism outside the cylinder, 
while that at the right shows the details of the fixed and movable 



Fig. 36. Tripping Mechanism of Low-Tension Ignitor, Electrodes in Contact before Sparking 

electrodes between which the spark occurs when they are suddenly 
snapped apart. In Figs. 36 and 37 are shown the details of the 
tripping device, the former illustrating the mechanism with the 
electrodes in contact just before sparking. 

Timing of Law-Tension System. Since the magneto is directly 
connected in a simple series circuit with each ignitor, it is evident 
that both the latter and the magneto itself must be timed to 
produce the spark at the proper moment for the explosion. The 



Fig. 37. Low-Tension Ignitor Tripping Mechanism, Showing Adjustment Spacing 

ignitor is tripped by a push rod and cam on the camshaft in 
exactly the same maimer as the valves are operated, while the 
magneto itself is timed to the motor in much the same manner 

.. . _ 83 



74 



GASOLINE TRACTORS 



360° 



as is necessary in the case of a high-tension magneto. In the 
section on elementary electricity it has been explained how an 
alternating current rises from zero to maximum in one direction 

and then subsides and rises 
again in the opposite direc- 
tion. This is termed a sine- 
wave current, and is illus- 
trated by Fig. 38. The only 
part of this current that is 
of value for ignition is repre- 
sented by the few degrees in 
the revolution of the arma- 
ture that are indicated by 
the peaks of the alternations. In a simple magneto with an H 
armature, Fig. 39, this peak occurs at the point shown in the 
illustration, that is, the point when the core of the armature is 
entering the tunnel formed by the pole pieces attached to the field 
magnets at their lower ends. 

In Fig. 39 the armature is turning to the left and has just 
left the right-hand pole piece by ^ inch. From this point until 




Fig. 38. Sine Wave Alternating Cur- 
rent as Generated by Magneto 



f(i T»ON_£F*^ 



the center of the core of the 
armature is on a line with the 
upper part of the pole piece, the 
value of the current is close to 
the peak and is rising. The 
further revolution of the armature 
causes it to fall, and when the 
core reaches the lower part of the 
tunnel, it reverses and starts 
upward ia the opposite direction. 
The armature of the magneto 
must accordingly be set so that it 
is in the position shown in the 

Fig. 39. Sparking Position cf Armature illustration when the ignitor is 

about to trip. This is not the maximum, as the armature cuts 
the greatest number of magnetic lines of force a few degrees 
further around and thus produces the current of the greatest 
value at that point. This setting allows for the necessary advance 



PO/A/r-B* 



MAGN£T~3' 




W/V7 



f^-MAGNET-2 



84 



Digitized by 



Google 



GASOLINE TRACTORS 75 

of the sparking time, which causes the latter to coincide with the 
point of maximum value just mentioned. 

Causes of Trouble Few. There being only a current of very 
low voltage in any part of the system and only a single short 
wire being necessary to conduct this low-tension current to the 
ignitors, electrical troubles are rare with the low-tension system 
and are confined chiefly to failure of the ignitors, or make-and- 
break plugs, to spark owing to an accumulation of carbon, or 
soot, on the electrodes. Apart from this, any shortcomings of the 
system are apt to be purely mechanical rather than electrical. 
The tripping mechanism and springs must necessarily be light, 
but at the speeds at which they operate wear is more or less 
rapid, so that considerable attention is required to maintain them 
in efficient operating condition. This is the chief reason why the 
low-tension ignition is not applicable to the high-speed type of motor. 

As before stated, most of the electrical difficulties experienced 
with the low-tension system involve the ignitors, or make-and- 
break plugs. Unless the fuel is being burned very efficiently by 
the engine, they short-circuit very quickly through a deposit of 
carbon, although this also occurs at regular intervals even where 
it .is not possible to improve upon the running of the engine. 
Another cause of trouble is the sticking together of the electrodes 
by what is practically a form of electric welding. Carbon deposits 
must be scraped off carefully, electrode contact surfaces filed or 
scraped bright, and the remainder of the plug cleaned with kero- 
sene. After a considerable time in service the mica insulation of 
these plugs may become so impregnated with carbon dust or a 
mixture of oil and carbon dust that it is impossible to prevent it 
short-circuiting, in which case it is necessary to replace the mica 
insulation. The plugs are the source of the trouble in about 85 
per cent of the cases, but when they are in good condition, the 
magneto should be tested, first, to note whether it is generating 
or not and, second, to see whether it is properly timed to the 
engine. To provide sufficient current at a good voltage, the 
plug must snap, or break, just at the moment when the current 
in the armature of the magneto is close to the peak, Fig. 39. 
The maximum current and voltage are generated when the arma- 
ture has turned a few degrees further. 



85 



Googjc 



76 GASOLINE TRACTORS . 

Testing Low-Tension Magneto. To test the armature to find 
out whether it is generating or not, attach a short piece of copper 
wire to its terminal, place the bare end of this wire against the 
field magnet, and rotate the armature. Pull the wire away from 
time to time, and a good spark will follow if the magneto is in 
good order. If this proves to be the case and the spark still 
fails to occur at the plug, the position of the armature should be 
noted at the moment that the plug breaks, and if this does not 
correspond with the position shown in Fig. 39, the magneto 
should be retimed. The plug itself may be tested by taking it 
out and laying it on the cylinder. With the magneto running, 
the electrodes may be snapped apart. Should they fail to spark, 
all other parts of the system being in good working order, it is 
usually due to the insulation of the plug. A spare plug should 
be inserted and the insulation of the old one replaced as soon as 
the opportunity arises. By carrying spares, much valuable time 
in the field may be saved. 

High-Tension Magnetos. Two Types. Two types of high- 
tension magnetos are employed for tractor ignition: one in which 
both windings are placed directly on the core of the H-type 
armature, so that the windings, core, and condenser rotate 
together; and the other, the so-called inductor type in which the 
winding is stationary while the rotor in two parts revolves on 
either side of it. The first type illustrates the elementary elec- 
trical principle that rotating a coil of wire through the lines of 
force of a magnetic field will induce a current in the wire. The 
current thus induced in the primary winding of the coil on the 
armature is transformed to one of high voltage by the secondary 
winding which is also on the armature. The gear shown at the 
right-hand end of the armature is for the purpose of driving the 
distributor disc, the function of which is explained later. 

The rotor and winding of an inductor type of magneto, the 
K-W, are shown in Fig. 40, while a phantom view of the complete 
machine is given in Fig. 41. It will be noted in Fig. 40 that the 
rotor consists of two blocks of iron placed at right angles to one 
another with the winding between them. In Fig. 41 the con- 
denser is at the left of the winding, while the contact box and 
the distributor of the magneto are at the right. The operation of 



86 



GASOLINE TRACTORS 77 

the inductor type of magneto is based on the principle that 
rotating a magnet so that its lines of force cut the winding of a 
coil will induce a current in the latter. The magnet in this case 
is the rotor, the members of which form part of the magnetic 
circuit of the machine. They are most strongly magnetic when in 
the position at which the current of any magneto is at the maxi- 
mum, as previously explained in connection with the low-tension 
magneto. The rotor takes its magnetism from the permanent 
magnets of the field in the same way that an ordinary horseshoe 



Fig. 40. Rotor of K-W Inductor Motor 
Courtesy of K-W Ignition Company, Cleveland, Ohio 

magnet will render an iron nail magnetic as long as they are in 
contact. 

High- Tension Circuit. The wiring of a true high-tension 
magneto, that is, one that has both the primary and the secondary 
windings embodied in the magneto itself, is almost as simple as that 
of the low-tension type already described; in the high-tension 
system one wire is necessary for each plug and in the low-tension 
system a single cable connected to a busbar in contact with all 
the ignitors is needed. But in the high-tension system these wires 
carry current at very high voltage and the slightest defect in the 
insulation or the presence of dampness is apt to permit this high- 
tension current to leak away, usually without giving any sign of 
its escape. 

The primary circuit of a high-tension system consists of the 
primary winding on the armature, whether stationary or rotating, 



87 Digitized by G00gle 



78 GASOLINE TRACTORS 

the condenser, and the contact breaker. The secondary circuit 
consists of the secondary winding (whether located on the arma- 
ture of the magneto itself in the form of a coil placed under the 
arch of the magnets in the magneto or placed independently of 
the magneto), the distributor, the cables leading to each of the 
spark plugs, and the safety spark gap. It will be noted that 
each case represents but one side of a circuit. The other side 
is grounded, that is, the current returns through the metal of the 
magneto in the primary circuit and through that of the motor 



Fig. 41. Phantom View of Complete K-W Inductor Magneto 
Courtesy of K-W Ignition Company, Cleveland, Ohio 

and the magneto in the secondary. Thus a spark plug with a 
cable attached completes the circuit when it is screwed into the 
cylinder. 

Contact Breaker. Regardless of detailed differences in their 
construction or design, all high-tension magnetos operate on the 
same principles, and in every case the contact breaker is the part 
of the magneto on which its continued operation depends. In 
Fig. 42 is shown a complete high-tension ignition system con- 
sisting of a K-W magneto and its connections for a four-cylinder 
motor. The contact breaker details are plainly shown just below 
the distributor of the magneto: C is a cam carried on the end of 
the magneto armature shaft; R is a roller carried at the center of a 
hinged arm which is pivoted at its right-hand end and is designed 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 79 

to minimize wear on the cam. At its left-hand end this same 
hinged arm carries a platinum contact point designed to make 
contact with a similar point that is held stationary, but is adjusta- 
ble for wear. The hinged arm and the stationary contact point 
are attached to the contact breaker box A, which may be turned 
through a partial revolution in either direction to advance or 
retard the time of sparking. 

The circuit through the primary winding on the armature is 
completed when the contact points P are together, and it will be 



MAGNETO 

Fig. 42. Ignition Circuit of Four-Cylinder Motor 
Courtesy oj K-W Ignition Company, Cleveland, Ohio 

noted that they are in contact with each other as long as the 
cam C is horizontal, so that current is flowing in this circuit. 
When the cam C turns so that it becomes vertical, it corresponds 
to the position of maximum current in the armature winding and 
the circuit is suddenly opened at that moment. This breaking of 
the current provides the impulse necessary to induce the maxi- 
mum current and voltage in the secondary winding. At the same 
moment that the contact breaker opens, provided the motor is 
designed to turn to the right, or clockwise, the distributor contact 
B is passing close to S, which is the terminal representing the 
spark plug of cylinder 1. If it is a left-handed motor, the dis- 

89 Digitized-by G00gle 



80 GASOLINE TRACTORS 

tributor contact B will be at the sparking point for cylinder 4 
at S'. There is accordingly a path open for the high-tension 
current to the spark plug. As the distributor is driven directly 
from the armature of the magneto by gearing, Fig. 43, the dis- 
tributor contact is at a point corresponding to the cylinder that is 
to be fired each time the contact breaker opens. 

Firing Order. While these points on the distributor are num- 
bered consecutively from 1 to 4, the cylinders of a four-cylinder 
motor cannot be fired in that order since the cranks of a four- 
cylinder four-cycle motor are spaced at 180°. In other words, 
there are two in one plane and the other two are in the plane 



Fig. 43. Distributor End of K-W Magneto 
Courtesy of K-W Ignition Company, Cleveland, Ohio 

opposite, or half a revolution away. Consequently, cylinders in 
the same plane cannot follow one another in firing. This is made 
plain in the circuit diagram, Fig. 42. From this illustration it is 
evident that cylinders 1 and 4 have their cranks in the same 
plane, so that the cylinder to fire after cylinder 1 must be either 
2 or 3. It will also be noted that contact 3 of the distributor 
corresponds to cylinder 4 of the motor, so that the firing order 
of this motor is 1, 2, 4, 3. The firing order most commonly 
adopted for four-cylinder motors is 1, 3, 4, 2 since this produces 
a somewhat better impulse balance by distributing the successive 
explosions among cylinders at equidistant points on the crankshaft. 
In checking up the ignition or making any repairs it is important 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 81 

to know what the firing order of the motor is, and this will usually 
be found stamped on it in some conspicuous place. 

Care of Magneto. Since modern high-tension magnetos have 
their shafts mounted on ball-bearings, they require very little oil 
and that only at infrequent intervals. A few drops once a week 
in the case of some and once in two weeks with others is all 
that is necessary so far as lubrication is concerned. 

The contact breaker is the most important part of the mag- 
neto and is the one that should be looked to first whenever the 
magneto fails to deliver a spark at the plugs, all other essentials 
of the system being in good condition. Long continued operation 
at full load is apt to burn the contact points away to such an 
extent that they do not come together when the cam is in the 
horizontal position. Or they become so pitted and covered with 
oxidizing material, which insulates them, that the current cannot 
pass even though they make contact. The contact points should 
be kept true and bright with a very fine thin file or with a strip 
of fine sandpaper, taking care to remove all traces of dust from 
the contact box by cleaning it out with gasoline or kerosene. 
Since the points are made of very expensive material, when they 
are trued up no more metal should be removed than is necessary 
to bring the surfaces squarely together. Much better service will 
be obtained from the magneto if this operation is carried out at 
frequent intervals, say once a month when the tractor is being 
used steadily, instead of waiting until the points get in such a 
condition that the magneto will not operate at all. If the contact 
points burn away very rapidly, it is an indication that the con- 
denser has broken down and should be replaced. This is usually 
a job that must be referred to the magneto manufacturer. Apart 
from the attehtion required by the contact breaker, the only care 
that it is necessary to give the magneto is to keep it clean and well- 
oiled and see that its connections are always tight. 

Spark Plugs. Regardless of how well every other part of 
the ignition system is working, a spark will not occur in the cylin- 
der unless the spark plugs are in good condition. The spark 
plug is the business end of the entire system since its failure will 
render useless the perfect functioning of every other part. As 
will be noted in the sectional view, Fig. 44, a spark plug consists 

Digitized by VjOOQ IC 



82 GASOLINE TRACTORS 

of two electrodes with a gap between them across which the 
current must jump in order to ignite the fuel in the cylinder. 
One of these. electrodes is the outer shell of the spark plug itself 
and completes the circuit through the ground return when it is 
screwed into the cylinder head. The other, or central electrode, 
is connected directly with one of the points ©n the high-tension 
distributor of the magneto, so that the path of the current is 
down through this central electrode, across the gap to form the 
spark and back through the body of the motor to the magneto, 
which is also grounded by being bolted to the motor. 

Importance of Insulation. No spark plug can be any better 
than the insulation which separates the two electrodes since the 
entire operation of the plug depends upon its pre- 
venting the escape of the current before reaching 
the gap. Like any other force under pressure, elec- 
tricity will always seek the line of least resistance, 
and as compressed air has a higher electrical resist- 
ance than any solid insulator, the slightest leak in. 
the insulation will open a path for the current and 
no spark will occur at the gap. 

Heat, vibration, hot oil, and soot are all enemies 
of the insulation, and under their combined attack 
it is bound to break down sooner or later. Soot, 
or carbon, which is an excellent conductor of elec- 
tricity, is the commonest cause of spark-plug failure, 
H fiew 4 ofa S lpi?k al but it: does not necessarily put the plug out of 
Plug commission for good. It is particularly difficult to 

prevent the accumulation of carbon on the ends of the plugs in 
an engine burning kerosene, but a good cleaning with a fine wire 
brush and plenty of gasoline is usually all that is necessary to 
restore them to service. 

Common Plug Troubles. Apart from the difficulty of short- 
circuiting due to carbon collecting on the ends of the plugs, the 
commonest causes of trouble are due to a hidden breakdown of 
the insulation and to the burning away of the electrode points, 
so that the resistance of the gap becomes too great for the current 
to bridge. Porcelain is one of the best insulators known for the 
purpose, but it is difficult to make a porcelain that will with- 



92 



Digitized by VjOOQIC 



GASOLINE TRACTORS 83 

stand the intense heat and the vibration indefinitely, particularly 
as the material is already under stress due to the screwing down 
of the gasket nut of the plug in order to make it gas tight. 
When it becomes intensely hot, the vibration and pounding are 
apt to open fine invisible cracks in the body of the porcelain. 
The carbon is forced into these and forms a conducting path for 
the current. As this carbon cannot be cleaned out, the plug is 
useless until a new porcelain has been inserted. 

In the same manner, the hot oil carrying a considerable per- 
centage of carbon particles is forced into the mica insulation of 
a plug until it becomes so impregnated with this conducting 
material that it will no longer spark. Only the replacement of 
the electrode and its insulator will cure the trouble. Failure to 
spark due to the electrode points having been burned too far 
apart sometimes makes itself apparent by the current visibly 
passing over the outside of the plug. That is, instead of jump- 
ing the gap inside the cylinder, the current finds a path of less 
resistance across the surface of the insulator. This will sometimes 
occur when a plug gets extremely hot, even though the points 
are properly spaced, and since water is a good conductor, it will 
always take place if the slightest amount of moisture is allowed 
to fall on the porcelain of the plugs. Dirty oil will also provide 
a conducting path. When the electrode points have burned too 
far apart and no indication is visible at the plug itself, the spark 
will be noticed jumping the safety spark gap on the magneto. 

Under the continued heavy service of a tractor engine that 
is being used for plowing ten hours a day and six days a week, 
it will be nothing unusual to have to adjust the spark plug 
points two or three times a week, particularly where cheap plugs 
are used, since the electrodes are of common iron and burn away 
very quickly. It is poor economy to buy cheap spark plugs, though 
it is not so great a sin as to buy cheap lubricating oil. The latter 
besides damaging the motor in other ways will cause added 
trouble with spark plugs of any kind owing to the excessive 
amount of carbon that accumulates in the cylinders. Leakage of 
compression through the plugs must be prevented by turning 
down the nut at the base of the porcelain to seat it on the 
gasket, but this must be done carefully or the porcelain will break. 



93 



Digitized by VjOOQ IC 



84 GASOLINE TRACTORS 

Wiring. Moisture and oil are also enemies of the insulation 
of the high-tension cables that connect the distributor terminals 
of the magneto with the plugs. These cables must be kept clean 
and dry and their terminals at both ends must be kept tight 
with the cables in a position where they do not come into con- 
tact with one another or with the body of the engine ks far as 
possible since despite the thickness of the rubber and the cotton 
insulation the high-voltage current will find a path through it at 
the slightest opportunity. When the cables have become soaked 
with oil and dirt, it is better to discard them and replace them 
with an entire new set as the value of the insulation has been 
destroyed to a large extent. 

In order to make the cables flexible, they are made up of a 
large number of fine copper wires stranded together. When the 
cables become frayed at the ends next to the plug terminals, 
particularly, it is nothing unusual for one or more of these very 
fine strands of copper to project against the body of the plug or 
some other metal and thus cause a short-circuit that is not 
noticeable. Both ends of the cables should be well taped at the 
terminals to prevent this. Contact with any moving parts must 
be avoided as even a slight amount of wear on the insulation 
will lower its resistance to a point where the current will find a 
path through it. This is particularly true of cuts that penetrate 
both the cotton and the rubber, but which may be so small as 
to be imperceptible. Despite their size the current will leak 
through them if the cables come in contact with any metal 
parts since almost any path of this kind will present less resist- 
ance than does the gap of the spark plug, especially when the 
latter has been burned open too far. 

Magneto Impulse Starter. Owing to the fact that it is not found 
practical in the majority of instances to carry a storage battery on 
a tractor, while the average tractor motor cannot be cranked fast 
enough by hand to start it with the ordinary magneto, an attach- 
ment has been designed for the latter by means of which it may 
be caused to generate sufficient current for a hot spark regardless 
of the speed of the engine. This is known as an impulse starter. 
It consists of a spring mechanism, which, when the engine is 
cranked, is automatically released, causing the magneto armature 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 85 

to turn through a partial revolution much more rapidly than the 
crankshaft. 

Bosch. The details of the Bosch impulse starter are shown in 
Fig. 45, while Fig. 46 illustrates the magneto complete as equipped 
with the starter. Referring to the detail view Fig. 45, it will be 
noted that a dish-shaped flange is attached to the armature shaft 
and that this flange carries two cams on its periphery. In the 
view at the right is shown the crossbar member which forms an 
integral part of the starter driving shaft. The squared ends of 
this bar fit the openings of the flange mentioned. This bar floats 
on the helical springs shown, which are held in a circular recess 
and are secured to the starter shaft, which is also the main driv- 



Fig. 45. Details of Bosch Impulse Starter 

Courtesy cf American Bosch Maoneto Corporation* 

Springfield, Massachusetts 

ing shaft, as is made clear in the assembled view of the magneto. 
The operation of this starter is controlled by a latch forming part 
of the external engagement lever, which is shown projecting 
upward. When it is not desired to operate the impulse starter, 
this latch is held away from the cams by a trigger. Releasing the 
trigger drops the latch, and the starter, or coupling shaft, is 
revolved, causing the spring to be compressed. Since the crossbar 
is held stationary, the armature does not revolve. By moving the 
small lever to the release position, the springs are freed and they 
give a rapid partial turn to the magneto armature. When the 
engine speed exceeds 150 r.p.m., the speed at which the cams 
strike the lever is sufficient to cause it to fly up out of the posi- 
tion where it is held by the trigger, so that the magneto operates 

95 



86 GASOLINE TRACTORS 

in the usual manner. For starting large engines, it is customary 
to prime the cylinders with gasoline; the impulse starter lever is 
then moved over to the engaged position and let go. The engine 
is cranked to bring the piston in a cylinder that is about to fire a 
few degrees beyond the upper dead center on the firing stroke, 
and then the starter lever is pushed to the release position, caus- 
ing a spark to occur in the cylinder under compression. To facili- 
tate starting in this manner, a check mark may be made on the 
flywheel to indicate the starting position. 

Eisemann. In Fig. 47 is illustrated the mechanism of the 
Eisemann magneto impulse starter, in which a spiral spring is 
employed as the driving element. For greater clearness, this 



Fig. 46. Bosch Magneto Equipped with Impulse Starter 

Courtesy of American Dosch Magneto Corporation, Springfield, 

Massachusetts 

spring is indicated by dotted lines. The spring S is attached to 
the members // and C, the former being the housing attached to 
the magneto shaft and the latter the driving member; B is a fixed 
bar which is mounted on the base of the magneto; and T is a 
floating member, or trigger. When the motor is cranked slowly, 
the trigger T drops by gravity, engaging the bar B and temporarily 
preventing the rotation of the housing H. Since C is driven by 
the engine, cranking causes it to compress the spring, or wind 
it up, until the cam on C strikes the wedge W. This forces the 
trigger upward until it slips off the lower bar, thus releasing the 
housing H and causing the spring to give the armature a sharp 
partial turn. The right-hand illustration shows the relation of the 



96 



Digitized by VjOOQ IC 



GASOLINE TRACTORS &7 

members after the spring has been released and the magneto 
starter is in its normal running position. Stops are provided on 
the housing and the outer part of the driver C to prevent the 
armature from being turned past the position it must maintain to 
be properly timed to the engine. To hold the starter out of 
operation while the engine is running, T is heavily counterbalanced 
and as a result the action of centrifugal force on it draws the part 
T further in until the detent on it, shown just above the trigger 



Fig. 47. Impulse Starter on Eisemann Magneto 
Courtesy of Eisemann Magneto Company, Brooklyn, New York 

itself, enters the notch N in the driving member C, where it is 
held as long as the magneto runs at its normal speed. As this 
notch provides a positive drive for the magneto independently of 
the spring, the starter acts merely as a coupling when running. 

TYPES OF MOTORS 

Wide Range of Types. When gasoline-driven tractors were 
first placed on the market with a view to providing a machine 
that could be more widely used than the steam tractor, they con- 
sisted of little more than a single-cylinder stationary gasoline 
engine on wheels. While tractor design has advanced considerably 
since that time, it is still a long way from having reached any 
standard as far as the power plant is concerned. Meanwhile, the 
automobile engine has undergone tremendous improvement, while 
its manufacture is now carried out on a scale that was not dreamed 
of fifteen years ago. As a result, the tractor engine has been 
developed under the influence of two widely separated standards, 

Digitized by VjOOQ IC 



88 GASOLINE TRACTORS 

first, that of the stationary engine builder and second, that of the 
automobile engine manufacturer. There is, consequently, a wide 



Fig. 48. Two-Cylinder Horizontal Motor Used on 20-40 Oil-Pull Tractor 
Courtesy of Advance-Rumely Thresher Company, Inc., Laporte, Indiana 



Fig. 49. Interior of Crank Case, Oil-Pull Motor 
Courtesy of Adiance-Rumely Thresher Company, Inc., Laporte, Indiana 

range of engine types used for tractor propulsion. At one end of 
this range there is the descendant of the original stationary 
engine, made more compact and with additional cylinders to provide 

98 Digitized by G00gle 



GASOLINE TRACTORS 89 

the needed extra power without excessive weight, while at the other 
extreme there is the light, high-speed, multi-cylinder motor, which 
to all intents and purposes is practically an automobile engine. 
Horizontal Engine. Oil-Pull. To a large extent the horizon- 
tal engine is an outgrowth of stationary engine practice. A repre- 



Fig. 50. Section of Eagle Two-Cylinder Horizontal Motor 
Courtesy of Eagle Manufacturing Company, Appleton, Wisconsin 

sentative example is illustrated in Fig. 48, which shows the 20-40 
Oil-Pull engine. The cylinders are cast with separable heads and 
the valves, located in the latter, are operated by rocker anps. 
The carburetor, or fuel mixer, the magneto, the force-feed oiler, 
and the circulating pump are all placed on top of the motor for 

Digitized by VjOOQ IC 



90 GASOLINE TRACTORS 

greater accessibility. Since splash lubrication cannot be used 
owing to the position of the cylinders, force-feed oilers with leads 
directly to each of the bearings are commonly used on this type 
of engine. In Fig. 49, is shown a head-on view of the same motor 
with the crankcase removed, showing the crankshaft and bearings, 
the camshaft and timing gears. The magneto, the circulating 
pump, and the force-feed oiler are also driven by the gears. In 
this engine the cylinders are slightly offset to reduce the pressure 
on the cylinder walls during the firing stroke. 

Eagle. A clearer idea of the internal details of this type of 
engine is obtainable from the sectional view, Fig. 50, showing an 



Fig. 51. Avery Two-Cylinder Horizontal Opposed Motor 
Courtesy of Avery Company, Peoria, Illinois 

Eagle two-cylinder motor. The upper cylinder has been sectioned 
through the center line of the piston, showing the piston pin and 
the inside of the valve cages, while the lower one illustrates the 
complete piston with its rings and the removable valve cages in 
the cylinder head. Whether it be horizontal or vertical, one of 
the advantages of the valve-in-head type of motor is the ease with 
which the valves may be kept in condition, grinding-in being an 
operation that must be carried out at frequent internals on a 
tractor engine. 

Horizontal-Opposed Avery. The horizontal opposed ; ^« v )e was 
largely used on automobiles for several years during ti : early 
period of their development in this country. It provides better 
impulse and mechanical balance than the two-cylinder type in which 

Digitized by VjOOQ IC 



Fig. 52. Engine of Holt Caterpillar Tractor 
Courtesy of Holt Manufacturing Company, Inc., Peoria, Illinois 



Fig. 53. Parts of Tracklayer Traotor Engine 
Courtesy of C. L. Best Gas Tractor Company, San Leandro, California 



101 Digitized by G00gle 



92 • GASOLINE TRACTORS 

the cylinders are placed side by side and is accordingly freer from 
vibration. In Fig. 51 is illustrated the Avery two-cylinder motor 
of this type, which is also built with four cylinders in the larger 
sizes. A novel feature of the Avery motor that overcomes the 
disadvantage to which this type was subject on the automobile is 




Fig. 64. Automobile Type Engine of Parrett Tractor 
Courtesy of Parrett Tractor Company, Chicago Heights, Illinois 

the use of removable cylinder liners. Owing to the weight of the 
piston resting on the lower half of the cylinder wall the latter 
wore out of round more rapidly than would the cylinders of a ver- 
tical engine in the same service. This destroyed the compression 
and involved the reboring of the cylinders and the fitting of over- 
size pistons. The Avery cylinder liners are cast of harder metal 



102 



Digitized by VjOOQ IC 



GASOLINE TRACTORS 93 

than the cylinders themselves and may be given a part turn from 
time to time so as to distribute the wear over the entire wall, 
while the liner itself may be replaced readily; 

Vertical Motors. Holt and Tracklayer. All the horizontal 
motors described are specially designed for tractor service by the 
manufacturers of the tractors themselves and produced in their 
own shops. With comparatively few exceptions, most of the ver- 
tical types of tractor motors are the products of the various large 



Fig. 55. Section cf Moline Four-Cylinder Motor 
Courtesy of Moline Plow Company ; Moline, Illinois 

automobile motor factories and are designed along lines that 
closely follow practice in the automobile field. One of these 
exceptions is the Holt motor shown in Fig. 52, while another of 
very similar design is the power plant of the Tracklayer tractor. 
Some of the construction details of this motor are shown in 
Fig. 53, which illustrates a cylinder casting, cylinder head with 
valves, piston, piston pin, and the cylinder head and manifold 
gaskets. Both of these motors are specially designed and built 



103 Digitized by G00gle 



94 GASOLINE TRACTORS 

for tractor service and are of the slow-speed type best adapted for 
carrying a large percentage of their maximum load continuously. 
Parrett. The Parrett motor shown in Fig. 54, while also 
designed for this service, follows automobile practice more closely. 
It is shown with the cylinder head casting and the crankcase oil 
pan removed to illustrate the accessibility thus obtained. Its 
smaller size and greater compactness is accounted for by the fact 

that it is a high-speed type, de- 
signed to produce its normal rated 
output at 1000 r.p.m. 

Moline. Another motor of this 
class is the Moline, which is shown 
in longitudinal section in Fig. 55 
and in cross-section in Fig. 56. 
These illustrations are taken from 
the Moline instruction book and 
the identification figures serve to 
make clear the functions of the 
various parts of a motor. From 
1 to 5 in Fig. 55 they refer to 
the lubricating system, as follows: 
1, oil level in crankcase; 2, suction 
pipe to oil pump; 3, oil pump; 4, 
oil conduit drilled through the 
crankshaft; and 5, oil lead to crank- 
pin bearings. Numbers 6 and 7 
are the driving pinion and gear of 
the timing gear; 8, a bevel gear for 
the belt pulley of the tractor; 9, a 

^ZS^^£f£St' valve ****•> 10 > the valve mech - 

Mdine, Illinois anism chamber; and 11, the oil 

cap filler and breather. The latter admits air to the crankcase and 
is a necessary feature of all motors but is usually located directly 
on the crankcase itself. It is one of the points that must be care- 
fully guarded against the entrance of dust and grit to the interior 
of the motor. 

In Fig. 56 1 is the oil screen; 2, the suction pipe to the oil 
pump; 3, the oil hole to the crankpin bearing; 4, the crankshaft* 



104 



Digitized by VjOOQIC* 



GASOLINE TRACTORS 95 

5, the crankpin; 6, the combustion chamber of one cylinder; 7, a 
valve; 8, the valve spring; 9, the rocker arm of the valve linkage; 
and 11, the rocker arm stud; 10 is the intake passage. The details 
of the crankshaft and piston assembly are shown in Fig. 57, in 
which 1 is the oil outlet hole from the drilled crankshaft at the 
forward crankshaft bearing; 2, the oil intake hole at the rear 



Fig. 57. Crankshaft and Piston Assembly of Moline Motor 

crankshaft bearing; 3, a series of threads designed to work the oil 
backward into the crankcase and prevent its entrance into the 
clutch housing; 5, the helical half-time gear for driving the cam- 
shaft and auxiliaries; and 6, the bevel pinion for driving the belt 
pulley. The bolts for fastening the flywheel to the crankshaft 
flange are identified by 4» 



105 r^ 

^Google 



Digitized by VjOOQI 



Is 

tt 

H 

gi 

if 



Digitized by VjOOQIC 



GASOLINE TRACTORS 

PART II 



CONTROL SYSTEM 
ENGINE GOVERNORS 

Need of Governors. Plowing. In order that a tractor may 
be operated most economically, it must be capable of one-man 
control since, in plowing, conditions are continually encountered 
where the driver's attention must be centered on the management 
of the plows and the steering of the machine to the exclusion of 
everything else. Moreover the demands upon the engine are con- 
tinually varying even when the soil conditions are apparently uni- 
form for long stretches. Stones, roots, and extra heavy patches 
of sod all impose considerable extra load on the engine that can 
be met satisfactorily only by an automatically controlled throttle 
if a uniform plowing speed is to be maintained. 

Belt Work. A far greater load variation is encountered in 
belt work than in plowing, as in the former the engine may be 
running practically idle at one moment and be almost choked 
down by overloading the next, whereas in the latter there is 
always a load on the engine and therefore the danger of racing is 
absent. Irregular speed under changing load, racing of the idle 
engine, and tardy opening of the throttle to meet the increased 
load, all of which are unavoidable with hand control, represent 
conditions of operation which not only reduce production at the 
machine being driven but are very bad for the engine itself as 
they result in overheating, prevent proper lubrication, and, not 
infrequently, result in burned-out bearings. In any case the pro- 
vision of a governor on the engine releases a hand for other and 
more productive labor. The majority of tractors go into service 
in the hands of an unskilled operator, and unless there is a governor 
on the engine, his course of instruction is likely to be marked by 
the occurrence of more or less damage that automatic control 
would prevent. 

Digitized by VjOOQ IC 



98 GASOLINE TRACTORS 

Centrifugal Governors. Despite almost innumerable attempts 
to displace it, the centrifugal principle first taken advantage of 
more than a century ago to control the speed of a steam engine is 
still in almost universal use for this purpose. Most tractor 
engines are equipped with what is commonly termed a fly-ball 
governor, though the details of the mechanism and the character 
of the throttle valve it is employed to control differ more or less. 
In its simplest form such a governor consists of two weights on 
the end of oppositely placed arms which are pivoted on a spindle 
connected to the throttle valve, either directly or through suitable 
linkage, so that any movement of the weights is communicated 
directly to the throttle. On a stationary engine the governor may 



Fig. 58. Simplex Engine Governor 
Courtesy of Duplex Engine Governor Company, Brooklyn, New York 

be placed upright and is not subjected to vibration or jolting, so 
that gravity alone may be depended upon to keep the weights in 
their normal position, but on the tractor springs are usually 
employed, and the governor may then be placed in any position. 
When running below a certain speed, either gravity or the pull of 
the spring is sufficiently strong to keep the weights together against 
the shaft or close to it. But as the speed increases, centrifugal 
force acts on the weights and tends to make them assume a posi- 
tion at right angles to the shaft. The faster the engine runs, the 
closer the weights approach to this position, but as their move- 
ment brings about a proportionate closing of the throttle, the 
engine is not given an opportunity to increase its speed. A well- 
balanced governor of this type will operate so sensitively that 



108 



Digitized by VjOOQ IC 



GASOLINE TRACTORS 99 

there will be practically no perceptible change in speed between 
idling and full load. So far as the tractor is concerned, centrif- 
ugal governors are of two general types, those that are an inte- 
gral part of the design of the engine and are built right into it 
and those that are in the nature of auxiliary devices designed to 
be attached to the inlet manifold between the carburetor and the 
intake valves. 

Auxiliary Types. The Simplex governor, shown in Fig. 58, 
and the Pierce, illustrated in Fig. 59, are, examples of governors 
designed to be adapted to any make of motor, the only modifica- 
tion necessary depending upon the details of the drive, since the 
governor must be driven directly from the motor itself. In the 



Fig. 59. Section of Pierce Engine Governor 
Courtesy of Pierce Governor Company, Anderson, Indiana 

Simplex the governor weights, which are housed in the casing just 
under and to the left of the oil plug shown, operate a grid valve 
the openings of which appear in the intake manifold flange at the 
left. The driving attachment, designed in this instance for a 
flexible shaft drive, appears at the right. Fig. 60 shows the 
attachment of a Simplex governor to a Continental motor, the 
drive in this case consisting of a solid shaft and bevel gears 
operating from the camshaft. The governor is set for the maxi- 
mum speed to which the motor on which it is mounted is best 
adapted and is then sealed, as shown at the left end. As the 
governor mechanism runs in a bath of oil, it requires no attention 
except to replenish the oil from time to time. 

109 



Fig. 60. Installation of Simplex Governor on Continental Motor of Bullock Tractor 
Courtesy of Bullock Tractor Company, Chicago, Illinois 



Fig. 61. Installation of Pierce Governor on Buda Motor • 

Courtesy of Pierce Governor Company, Anderson, Indiana *r* 



1,0 Digitized by G00(£le * 



GASOLINE TRACTORS 101 

The Pierce governor, which is shown in horizontal section, 
operates a conventional butterfly type of throttle valve such as is 
used in the majority of carburetors. This valve is shown at the 
left, while the weights and the driving attachment are at the right. 
Between the two is the spring against which the centrifugal force 
of the revolving weights must act to close the throttle. Just above 



Fig- 62. Built-in Governor of Creeping-Grip Tractor 
Courtesy of Bullock Tractor Company, Chicago, Illinois 

the left-hand end of this spring will be noted a screw adjustment 
by means of which the speed for which the governor is set may be 
altered. Increasing the tension of the spring by screwing this in 
permits an increase in the speed of the motor since the weights 
must then revolve at a higher speed in order to overcome the pull 
of the spring. This is the principle upon which the adjustment of 



in 



Digitized by VjOOQ IC 



102 GASOLINE TRACTORS 

all centrifugal governors is based. One method of attaching the 
Pierce governor is illustrated in Fig. 61, which shows it mounted 

on a Buda motor and driven 
through bevel gearing from the 
camshaft. 

Built-in Types. The part 
sectional end view of the engine 
of the Creeping Grip tractor, 
Fig. 62, illustrates an excellent 
example of a built-in governor. 
This is driven from a transverse 

Fig. 63. Governor and Magnetic Unit of »haft which takes its power 

co^VfJZJ^ ESU. th ™S h helical cut 8**™* from 

Chicago,- iuinmB t h e timing gear of the motor, the 

3ame shaft also serving as the magneto drive. In expanding, 

the revolving weights draw in the sliding shaft shown, which is 

linked to a bell-crank lever at its outer end. The lever is attached 

to the throttle, which will be noted just to the right of the carbu- 



Fig. 64. Emereon-Brantingham Motor, Showing Governor 
Courtesy of Emerson- Br antingham Company, Rockford, Illinois 

retor. This bell-crank lever is also attached by linkage to a dash 
pot to prevent the governor from "hunting," or "surging," as it is 



112 



Digitized by VjOOQIC 



GASOLINE TRACTORS 103 

variously termed, that is, fluctuating violently over a wide speed 
range. This governor is designed to control the speed of the 
motor between a minimum and a maximum of 400 to 700 r.p.m. 
and is adjustable by means of the hand lever shown in Fig. 63, 
which illustrates the combined governor and magneto unit before 
attachment to the motor. 

In Fig. 64, which shows the complete power plant of the 
Emerson-Brantingham 12-20 tractor, is illustrated another type of 
built-in governor, the details of which are clearly shown. This 
governor is driven by a belt and is of the usual steam-engine type 
in which the weights are carried on leaf springs, the movement 
being transmitted to the throttle through the linkage shown. 

TRACTOR CLUTCHES 

Functions of Clutches. Since the internal combustion motor 
cannot be started under load and will stall if the load be applied 
too suddenly, even though the engine is developing its full power, 
it is necessary to employ a means of picking up the load gradually 
as well as of connecting or disconnecting the motor from the load 
as desired. This means is the clutch; and clutch problems on the 
tractor are the same in kind but greater in degree than those 
encountered on the automobile since the load to be started is so 
much greater. An automobile need start its own weight only and 
in doing so it encounters but slight rolling resistance, whereas the 
tractor must not only get a very much greater weight under way 
but in starting it must overcome the far greater resistance repre- 
sented by the plows or other load and also that of the ground 
itself. 

As a general rule the types of clutches employed on tractors 
are the same as those used on automobiles, but they are given a 
considerably increased area of contact surfaces and these surfaces 
are held together under much higher spring pressures in order to 
carry the heavier load. Regardless of its type, the principle of 
the friction clutch is based upon holding the driving surface 
(directly connected to the motor) and the driven surface (directly 
connected to the transmission or speed reduction gear) in contact 
under a pressure per square inch that is greater than that exerted 
by the engine in carrying the load. When the pressure required 

113 



104 GASOLINE TRACTORS 

to carry the load exceeds that exerted by the clutch spring, the 
contact surfaces slide upon one another and the clutch is said to 
slip. Unless this slipping took place, some one of the links in the 
transmission between the wheels or tracks and the engine would 
have to give way or the engine itself would be stalled by the load. 
It is accordingly the function of the clutch to slip, first, to insure 
gradual engagement in picking up the load and, second, to pre- 
vent damage to the transmission or the motor when the load 
becomes excessive. The latter function, how r ever, is more impor- 
tant in theory than in practice since an excessive load almost 



Fig. 65. Transmission Unit of Illinois Tractor Showing Multiple-Disc Clutch 
Courtesy of Illinois Tractor Company, Bloomington, Illinois 

invariably stalls the motor before the clutch begins to slip, unless 
its surfaces have become glazed through wear or its spring has 
weakened. 

Types of Clutches. In practically every case the flywheel of 
the motor itself forms the driving member of the clutch. The 
driven member may be a cone faced with asbestos-wire fabric, a 
plate faced with similar friction fabric, or a contracting band 
similarly faced which is mounted so as to contact with the rim of 
the flywheel itself or with that of a smaller drum attached to the 
flywheel; or friction-faced shoes may be arranged to expand 
against the inner face of the flywheel. The moving force in every 
case is the clutch spring. In the order mentioned, these types are 
known as the cone, plate, contracting-band, and expanding-band, 



114 



GASOLINE TRACTORS 



105 



or expanding-shoe, clutches. Where a greater contact area is 
desired than is afforded by the diameter of the flywheel, a series 
of plates or discs is employed. These plates are divided into two 
groups, one of which is carried on spindles or bolts attached to 



4S6&ST05 *!"<* 




Clutch StAfrBx 



-Tfcirrt on Fl«* wHtei ib ettete 5ur-srA{Ttc 

Fig. 66. Section of Dry-Plate Clutch As Used on Moline Tractor 
Courtesy of Moline Plow Company, Moline, Illinois 

the flywheel and forms the driving member, while the second 
group is similarly mounted on members attached to the clutch 
shaft and forms the driven member. When in engagement, the 
two groups are pressed together by the clutch spring in the same 
manner as m other types of clutches. This clutch is known as the 



115 



Digitized by 



Google 



106 t GASOLINE TRACTORS 

multiple-disc type, and in some instances it operates in a bath of 
lubricating oil, the latter being squeezed from between the plates 
as they come in contact, thus ensuring gradual engagement. In 
Fig. 65 is shown the multiple-disc clutch of the Illinois tractor, 
the clutch being the small group of plates shown at one end of the 
transmission unit. 

Plate Type. The sectional diagram, Fig. 66, not only serves 
to illustrate the details of the dry-plate clutch but also makes 
clear the principles of clutch operation. This is the Borg and 
Beck clutch as used on the Moline tractor. One of the asbestos 



Pig. 67. Main Clutch of Holt Caterpillar Tractor 
Courtesy of Holt Manufacturing Company, Inc., Peoria, Illinois 

rings shown is attached to the flywheel, while the second ring is 
carried on the driven clutch member, while between the two is the 
clutch disc, which is a ring or disc of steel also attached to the 
clutch shaft. By means of the collar and toggle levers which mul- 
tiply the force exerted by the spring, this clutch disc is clamped 
between the two asbestos rings when the clutch is engaged. The 
backward pressure, or reaction of the spring, is taken on the ball 
thrust bearing shown, this being an essential of all types of cone 
or plate clutches since otherwise this back pressure of the spring 
would cause considerable frictional resistance to the revolution of 

Digitized by VjOOQ 1C 



GASOLINE TRACTORS 107 

the clutch shaft. The screw marked A is an adjustment to main- 
tain the distance B indicated, this distance being necessary for 
the complete release of the clutch when disengaged. 

Expanding-Shoe Type, The Lauson tractor clutch affords an 
example of the expanding-shoe type which calls for very little 



Fig. 68. Friction Transmission of Heider Tractor 
Courtesy of Rock Island Plow Company, Rock Island, Illinois 

explanation. Against the inner face of the flywheel are two 
pivoted shoes which are counterbalanced. These shoes are faced 
with asbestos brake lining and are designed to be held in contact 
with the inner face of the flywheel rim by means of the toggle 
mechanism shown. The spring has the same location as in other 



117 Digitized by G00gle 



108 GASOLINE TRACTORS 

types of clutches, while its purpose, like that of other clutches, is 
to hold the clutch friction surfaces together under a pressure 
greater than that exerted by the engine in driving the tractor 
under load. The main clutch of the Holt caterpillar tractor is of 
a similar type, Fig. 67. 

Contracting-Band Clutch. Neither the contracting-band nor 
the cone clutch calls for much description. The contracting-band 
clutch is practically a duplicate of the usual brake mechanism in 
which a friction-lined band is pressed against a revolving drum to 
bring the latter to a stop. In the case of such a clutch the object 
is to bring the contracting band to a stop on the drum, which is 



Fig. 69. Bevel Friction Transmission of Square Turn Tractor 
Courtesy of Square Turn Tractor Company, Norfolk, Nebraska 

the flywheel, so that both the band and the flywheel revolve 
together, this really being the only difference between the brake 
and the clutch mechanism. The contracting band is attached to 
the clutch shaft, or driven member, and when in operation, 
revolves with it, thus carrying the load. This clutch is used in 
connection with a planetary type of transmission and is accord- 
ingly familiar through its employment on many thousand Fords. 
Cone Clutch. In the cone clutch the inner face of the fly- 
wheel is turned to a bevel of approximately 30 degrees to form 
the driving member into which a cone-shaped member with the 
same bevel and lined with asbestos or other friction facing is 



118 



GASOLINE TRACTORS 109 

pressed by the spring. Owing to the necessarily limited area of 
friction contact in this type of clutch, a high spring pressure is 
necessary where a heavy load must be transmitted. 

On the automobile this spring pressure is very much less than 
on the tractor owing to the slight resistance encountered by the 
machine in starting, so that the clutch may readily be disengaged 
with the foot through the medium of a short lever and pedal, but 
on any tractor except a very light one the effort required to do 
this would be excessive. The usual method of clutch operation on 
the tractor is accordingly by means of a long hand lever provided 
with a ratchet or locking detent, so that the clutch may be held 
out of engagement. Since it does not benefit the spring to keep it 
compressed, the clutch should not be locked out of engagement 
any longer than is necessary to shift the transmission gears to 
neutral, when the clutch should again be allowed to engage. 
Holding the clutch out of engagement overnight or while the 
tractor is standing in the field subjects the clutch spring to abuse 
and will soon result in weakening it to the point where the clutch 
slips whenever any extra load comes on it. 

Friction J)rive. While all the types of clutches mentioned 
are, in a sense, a friction drive in that friction is depended upon 
to transmit the power, the so-called friction drive is one in which 
the load transmitting members revolve independently of one 
another except for a single point, or line, of contact. This is 
made clear by the illustration of the friction transmission of the 
Heider tractor, Fig. 68. The flywheel is the driving member, as 
usual, but in this case its entire outer rim is covered with a 
special friction facing consisting of hard fiber. The flywheel 
rotates between two large steel discs, either one of which may be 
pressed against it. In this instance the left-hand disc is used for 
forward movement and the right-hand disc for backing, or reverse. 
It is also apparent that the point at which the flywheel makes 
contact with the disc determines the speed at which the latter and 
the tractor itself are driven. 

In the position shown the tractor speed will be the lowest 
provided, since the flywheel is in contact with the outer edge of 
the disc, so that the relation of the two is that of a small gear to 
a large one and the speed of the latter is reduced. As the fly- 

1,9 • ■• Digitized by G00gle 



110 GASOLINE TRACTORS 

wheel moves toward the center of the driven disc, the relationship 
between the two becomes that of driving and driven gears which 
approach closer and closer to the same size, so that the speed of 
the driven member is increased. This movement of the flywheel 
is accomplished by mounting the motor itself on slides on the 
frame and moving it backward or forward by means of a large 
hand lever, ^he direction of movement of the tractor depends 
upon which disc is pressed against the flywheel. 



Both Wheels Forward **** vrneet* newer sen ueji wneei torwora 



<v»g/M »r /sect never sea 



Fig. 70. Details of Operation of Bevel Friction Transmission 
Courtesy of Square Turn Tractor Company, Norfolk, Nebraska 

Bevel Frwtion Drive. The form of friction drive employed on 
the Square Turn tractor is shown in Fig. 69. In this drive the 
principle is exactly the same as already outlined, except that 
friction-faced (fiber) conical members take the place of the fly- 
wheel as the driving member and corresponding cones of iron are 
the driven members. The design is also modified to permit of 
driving either rear wheel independently or both in different direc- 
tions at the same time in order to turn short corners. The small 
diagrams showing the different relations in which the driving and 
driven members may be placed, Fig. 70, explain the operations 
much better than a description. A separate hand lever controls 



120 



Digitized by VjOOQIC 



GASOLINE TRACTORS 111 

each of the driven discs, or traction members. Moving both of 
them forward drives the machine ahead through both driving 
wheels; pulling them back reverses the movement; and each may 
be used independently, so that one drives forward while the other 
is backing, thus turning the machine as if on a pivot. 

TRACTOR TRANSMISSIONS 

Speed vs. Weight. The power generated in an engine, 
whether by the expansion of steam or that of the ignited gases in 
an oil engine, is converted into mechanical energy by applying it 
to the movement of weight, and the power itself is represented by 
the extent of that weight and the number of times per minute 
that it is moved. Hence, for a given power the slower the speed 
at which the engine runs, the heavier must be the weight moved 
since it is set into movement a smaller number of times per min- 
ute. By increasing the speed, or number of impulses per minute, 
the weight moved can be correspondingly reduced. This fact 
explains why 25 hp. may be generated by a single cylinder sta- 
tionary gas engine running at 250 r.p.m. or by a four-cylinder 
motor running at 1000 r.p.m. and why one motor is scarcely more 
than one-eighth the size of the other, although their power output 
is the same. The single cylinder engine will weigh 2 tons or more 
and will have flywheels of large diameter weighing more than the 
total weight of the smaller engine, but both move the same amount 
of weight per minute. 

Automobile Practice. On the automobile the object of the 
designer is to keep the total weight down as much as possible con- 
sistent with reliability, so that light high-speed motors running up 
to 2000 r.p.m. or higher are employed. Such motors are practical 
for automobile use because the speed ratio between the driving 
and driven members — the motor and the rear wheels — is not 
excessive despite the high speed of the motor. 

Tractor Practice. But on the tractor, where the maximum 
speed in plowing cannot exceed three miles per hour and is pref- 
erably less than that (2J miles per hour is recommended by the 
Society of Automotive Engineers and most tractors are designed 
to plow at 2\ miles per hour), the higher the speed of the motor, 
the greater the number of steps required in the gear reduction, and 
each step represents a loss of power in friction as well as addi- 



121 Digitized by G00gle 



112 GASOLINE TRACTORS 

tional parts to wear out. Since the tractor is not subject to the 
same weight limitations as the automobile, there is no advantage 
in employing a light high-speed motor. Generally speaking, the 
slower the speed of the motor consistent with the avoidance of 
excessive weight, the better adapted it is to tractor use. The 
slow-speed motor running at 450 to 750 r.p.m. also has the further 
advantage of subjecting its moving parts to less rapid wear in 
service and, other things being equal, should require less attention 
to keep in satisfactory running condition. 

Function of Transmission. In the section on tractor motors 
it has been pointed out that the types in general use belong to 
two distinct classes: those which have developed with the station- 
ary engine as a basis; and those that are an outgrowth of auto- 
mobile practice. In either case the engine will only develop its 
normal rated power when allowed to run steadily at a rate close 
to its maximum speed. A gear reduction must accordingly be 
interposed between the motor and the driving members of the 
tractor; the speed of the motor determines how great this reduc- 
tion must be, while the space and the limit of weight available 
determine what form it will take. Whether consisting of a com- 
pact unit such as is used on the automobile or of large pinions 
and gears occupying the entire space between the frame members 
of the tractor, this speed reducing mechanism is usually termed 
the transmission. This name includes everything between the clutch 
and the final application of the power to the wheels or the tracks, 
which is termed the final drive. 

Wide Range of Types. Since tractor motors differ so widely, 
there is naturally a correspondingly wide range of types of trans- 
missions, the latter varying all the way from what is practically a 
duplicate of the gear train used on heavy steam tractors, or road 
rollers, to the light and compact gear box used, on high-speed 
automobiles. A few illustrations of typical examples of each class 
will suffice to give an idea of how widely this feature of the trac- 
tor varies on different designs. In comparing these, it should be 
borne in mind that while increased width of gear face affords a 
larger wearing surface to carry the load agd large gear diameter 
means fewer steps in the reduction, these advantages may be offset 
by the exposure of the gears to dirt and mud. 

122 Digitized by G00gle 



GASOLINE TRACTORS 113 

The great differences in size and weight, in many cases where 
the same amount of power is to be transmitted, are accounted for 
by a similarly great difference in the character of the materials 
used. Small pinions and gears running at high speeds must be 
made of alloy steels, hardened and toughened by heat treatment, 
and must be run in a bath of oil. Large broad-faced gears, on 
the other hand, may be made of steel castings or even cast iron, 
and it is the usual practice to run them to a great extent without 
protection. 

Speeds. Since the speed range of the average farm tractor is 
necessarily very low, its requirements are usually covered by the 
provision of but two forward speeds and one reverse. A few 
machines are provided with three speed transmissions, but this is 
the exception and is due to the use of either a high-speed motor 
or an automobile-type transmission. On low gear, which is equiva- 
lent to a forward speed of about one mile per hour, the speed 
reduction between the motor and the driving wheels of the tractor 
may range all the way from 40-1 to 80-1, that is, the motor 
makes 80 revolutions to a single turn of the driving wheels in the 
second case mentioned. Such a great difference between the motor 
speed and that of the machine itself necessitates a number of gear 
reductions, each one of which involves a power loss in itself and 
also presents an extra wearing surface that needs replacement 
sooner or later. Generally speaking, the lower the speed of the 
motor consistent with the avoidance of excessive weight, the less 
loss there will be in the transmission of the power to the rear 
wheels or tracks, as the case may be. The point below which it 
does not pay to reduce the motor speed appears to line between 
400 and 500 r.p.m., as beyond that the weight increases all out of 
proportion to the advantage gained, while the upper limit lies 
between 700 and 800 r.p.m.; that is, a low-speed motor would 
govern between these limits, say 450 to 750 r.p.m., and its trans- 
mission would be designed to take care of the difference between 
750 r.p.m. and the number of turns per minute made by the 
driving wheels, which would depend upon their diameter. 

A high-speed motor, on the other hand, would run at 1000 to 
1200 r.p.m. and its power would fall off very rapidly the moment 
its speed dropped below 800 r.p.m. To avoid an excessive number 

123 Digitized by G00gle 



114 GASOLINE TRACTORS 

of gear reductions, the driving wheels of a tractor equipped with a 
high-speed motor would usually be made comparatively small, 



Kg. 71. Friction Drive of the Port Huron 12-25 H.P. Faro Tractor 
Courtesy of Port Huron Engine and Thresher Company, Pvri Euro,. Alici jm 



124 



GASOLINE TRACTORS 115 

' which is a disadvantage since such a tractor is constantly climbing 
the grade formed by its small wheels sinking into soft earth, or 
depressions, and is accordingly expending £ large fraction of its 



Fig. 72. Plan View of Avery Transmission 
Courtesy of Avery Company, Peoria, Illinois 

power in lifting itself rather than in driving ahead. It does not 
necessarily follow that a tractor equipped with a high-speed motor 
always has small driving wheels, since the reduction in speed 
required may be taken care of in the final drive. 

125 Digitized by G00gle 



116 GASOLINE TRACTORS 

Heavy Types. Those transmissions which, as already men- 
tioned, represent a continuance of the practice followed for years 
on heavy steam tractors and road rollers are known as heavy 
types. Such a transmission is shown in Fig. 71, which gives a plan 
view of the Port Huron 12-25 friction-driven tractor. It also 
affords an example of a tractor with a comparatively high-speed 
engine equipped with large driving wheels. There are three gear 
reductions in all: the first will be noted at the left; the second is 
from this transverse shaft to a central gear on a shorter transverse 
shaft which also carries two small pinions meshing with the bull 



Fig. 73. Transmission ana Differential of 75 HP. Tracklayer Tractor 
Courtesy of C. L. Best Gas Tractor Company, San Leandro, California 

gears. Ordinarily the bull gears are attached directly to the driv- 
ing wheels, but in that location it is difficult to protect them, 
while in the present design they are completely encased. 

Since a tractor must make very short turns and both wheels 
must be driven when going straight ahead, a differential is indis- 
pensable. When rounding a short turn, it will be evident that the 
wheel on the outside of the curve must travel a much greater dis- 
tance than that on the inside and that if both were driven at an 
equal speed, one would be forced to slip and impose a heavy 
strain on the machine. If the ground condition were such that 
the wheel would not slip, rounding the turn would be difficult. 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 



117 



In the Port Huron tractor illustrated the differential is located in 
the second transverse shaft which carries the pinions meshing with 
the bull gears. As changes in speed are effected through the fric- 
tion drive, the gears of this transmission are constantly in mesh. 

The Avery transmission shown in Fig. 72, is another example 
of the heavy type, the illustration showing the relation of the 
horizontal motor to the transmission. The two forward speed 
reductions are represented by the two pinions of different sizes 
carried directly on the crank- 
shaft of the motor, while the 
reverse speed is the pinion 
just forward of these. The 
transverse shaft just under 
the rear end of the motor 
embodies the differential the 
housing of which will be noted 
at the right. This shaft also 
carries the pinions meshing 
with the bull gears. The com- 
plete power plant is carried on 
a sliding frame, and the differ- 
ent speed changes are effected 
by moving the motor so as to 
bring the different pinions into 
mesh with the large gear car- 
rying the differential. 

Intermediate Types. Be- 
tween the heavy types just 
described and what is prac- 
tically a motor-truck transmission, there are a number of trans- 
missions that conform to some degree with automobile gear-box 
practice but are built on much heavier lines, for example, the 
transmission of the Best 75 hp. tracklayer type tractor shown in 
Fig. 73. Sliding gears are employed for the speed changes, and a 
bevel pinion and driving gear on the counter-shaft which incorpo- 
rates the differential, the internal bevel gear of which shows plainly 
in the illustration. A typical automobile-type transmission is the 
Cotta, Fig. 74, as used on the Four Drive tractor. 



Fig. 74. Cotta Automobile Transmission of Dog- 
Clutch Type As Used on Four-Drive Tractor 
Courtesy of Cotta Transmission Company, 
Rod: ford, Illinois 



127 



Digitized by 



Google 



118 GASOLINE TRACTORS 



Fig. 75. Transmission and Spring Drive Differential of 10-30 Oil-Pull Tractor 
Courtesy of Advance- Rumely Thresher Company, Inc., Laporte, Indiana 



Fig. 76. Transmission of Turner Tractor 

Courtesy of Turner Manufacturing Company, Port Washington, 

Wisconsin 



128 



Digitized by VjOOQIC 



GASOLINE TRACTORS 119 

A clearer view of the details of the mechanism of a differential 
is shown in Fig. 75, which illustrates the Rumely 16-30 transmis- 
sion. One of the features of this differential is the use of a series 
of eight springs for taking up the shock of starting which will be 
noted just inside the large gear. Upon engaging the clutch, these 
springs must first be compressed before the load falls upon the gear 
teeth, thus cushioning the latter. Other similar transmissions are 
the Turner, Fig. 76, the Hart-Parr, Fig. 77, and the Nilson, Fig. 78. 



Pig. 77. Transmission of Hart-Parr Tractor 
Courtesy of Hart-Parr Company, Charles City, Iowa 

Special Types. In Fig. 79 is shown a plan view of the trans- 
mission of the Twin City 25-45 tractor, a feature of which is the 
use of toothed, or dog, clutches, the details of which are clearly 
shown. This view also shows the contracting-band clutch used on 
this machine. The dome just to the right of and forward of the 
flywheel houses the engine governor. Automobile practice is 
closely approached in the Yuba transmission, Fig. 80, and in the 
Holt caterpillar transmission, the gear box of the 10-ton Holt 



.Google 



Digitized by VjOOQI 



Fig. 78. Transmission of Nilson Tractor 
Courtesy of Nilson Tractor Company 



Fig. 79. Contracting-Band Clutch and Transmission of Twin City Tractor 
Courtesy of Minneapolis Steel and Machinery Company, Minneapolis, Minnesota 



130 



Digitized by VjOOQlC 



Fig. 80. Dual Automobile Type Transmission of Yuba Tractor 
Courtesy of Yuba Manufacturing Company, McrysvUle, California 



Fig. 81. Transmission of 10-Ton Holt Caterpillar 
Courtesy of Holt Manufacturing Company, Inc., Peoria, Illinois 



131 Digitized by GoO< 



122 GASOLINE TRACTORS 

tractor being shown in Fig. 81. Both these types are of the selec- 
tive sliding-gear type generally used in automobiles, the Yuba 



Fig. 82. Worm Drive of Sandusky Tractor 
Courtesy of Dauch Manufacturing Company, Sandusky, Okia 



Fig. 83. Transmission of Iluber Light Four Tractor 
Courtesy of Iluber Manufacturing Company, Marion, Ohio 

transmission clearly showing the individual clutches which are 
used in the tracklaying machine to enable the operator to drive 
either track separately when turning. A feature taken directly 



132 



GASOLINE TRACTORS 123 

from automobile practice is the use of the worm drive, Fig. 82. The 
Huber, Fig. 83, is a type that is in a class by itself. Its details 
and method of operation are clearly indicated in the illustration. 
Final Drive. As in the case of the automobile there is a 
further speed reduction between the engine and rear wheels in the 
final drive, but as the speed reduction between the tractor engine 
and its driving members, whether the latter be wheels or tracks, 
is so great, this cannot take the form of a small pair of bevel 



Fig. 84. Sectional View of Emerson-Brantingham Company Transmission, Showing Oil Level 
Courtesy of Emerson-Brantingham Company \ Rocl;ford t Illinois 

gears. The usual method is to employ bull gears, or internal gear 
rings of large diameter which are bolted to the driving wheels and 
with which small pinions on the ends of the transverse shafts of 
the change-speed gear mesh. In some instances automobile prac- 
tice is followed by using a live axle. This is a combination of a 
sliding change-speed gear of the selective type with a planetary 
gear. The sectional view of the Emerson-Brantingham transmission, 
Fig. 84, clearly shows the relation of the selective sliding gears and 
the oil level necessary for lubrication. 



133 



Fig. 85. Details of Final Drive, or Trick of Holt Caterpillar Tractor 
Courtesy oj Holt Manufacturing Company ', Inc., Peoria, IUinoU 



Fis. 8G. rind Dilve of C. L. Best Tracklayer Tractor 
Courtesy of C. L. Best Gas Tractor Company, San Leandro, California 



I 



Fig. 87. Details of Final Drive of Yuba Ball-Tread Tractor 
Courtesy of Yuba Manufacturing Company, MarysviUe, California 



134 



Digitized by 



Google 



GASOLINE TRACTORS 126 

final drive in tracklaying machines is usually through large 
sprockets on the ends of the transverse shaft, these sprockets 
meshing in the track itself. The track runs on rollers or balls 
and passes around an idler at the end of the tread, this idler 
being made adjustable so as to vary the tension on the con- 
tinuous track. The details of the Holt caterpillar, the Best 
tracklayer, and the Yuba ball-tread machines of this type are 
shown in Figs. 85, 86, and 87, which make the principles of 
operation so clear that further explanation is unnecessary. 

Only a brief mention has been made of a few of the differ- 
ent types of transmissions and final drives employed on tractors, 
there being so many that it would be out of the question to 
attempt to describe all of them, particularly since not a few 
have numerous special features. The foregoing examples, how- 
ever, cover the principles employed in practically all tractor 
transmissions and suffice to make clear the manner in which 
these principles are applied. 

TRACTOR OPERATION 

GENERAL INSTRUCTIONS 

Tractors Different in Design but Alike in Care Required. In 

the foregoing pages an attempt has been made to outline briefly 
the principles of tractor operation with just sufficient references 
to actual types to make the text clear. At the present stage of 
development it is hardly possible to select any one manufacturer's 
product as typical of tractor design in general or as embodying 
throughout those features of design which are most likely to become 
standardized during the next five years of development. There are 
so many different makes on the market and frequently so many 
models of each make that it would require a volume larger than the 
present one merely to give a brief description of all of them. Con- 
sequently, no extended descriptions of any tractors are given here. 
While designs and details of construction differ so widely 
and so frequently, all oil or gas engine tractors are based on 
certain underlying principles and all call for the same kind of 
care. The remainder of this article is accordingly devoted to 
an outline of the methods of handling tractors in service with a 

, 18fi Google 



126 GASOLINE TRACTORS 

view to pointing out clearly just the kind of care the machine 
needs to keep it running efficiently. To facilitate reference, this 
information is put in the form of questions and answers grouped 
under the particular subjects which they cover. 

Degree of Care Necessary. Before taking up the detailed 
consideration of tractor operation it is well to revert for a moment 
to the comparison between the automobile and the tractor in 
order to emphasize the great difference in the conditions of oper- 
ation of the two. It is a great mistake for the owner or operator 
of a tractor to conclude that because he can keep his car running 
for weeks at a time and subject it to the severest kind of service 
without being called upon to give it more than passing atten- 
tion at infrequent intervals, the same amount of care will suffice 
to keep the tractor running equally well. The most severe 
service to which an automobile can be subjected is trifling com- 
pared to what a tractor must undergo in plowing ten hours a 
day. No comparison between the two is possible. The atten- 
tion demanded in running a tractor is really only comparable to 
that required by a marine engine which is run steadily at full 
power. 

It is naturally impracticable to employ more than one man 
to run the average tractor so that the single operator must 
assume the combined tasks of the oiler, engine-room attendant, 
and engineer on watch in the engine room of a steamer. He 
must see that every part is constantly lubricated, must watch 
all moving parts in sight from time to time and keep all his 
senses on the alert all the time to detect the first indications of 
overheating or faulty operation as evidenced by the sounds 
produced. 

Parts Giving Most Trouble. Over two thousand tractor 
owners sent in reports in answer to a questionnaire forwarded to 
them by the Department of Agriculture. In answer to the ques- 
tion "What part of your tractor gives you most trouble?" more 
than seven hundred mentioned some part of the motor and of 
that number considerably over one-half gave the ignition as the 
chief source of delay. A leading tractor manufacturer substan- 
tiates this by stating in his instruction book that the motor is 
responsible for fully 75 per cent of all tractor troubles and that 



Digitized by VjOOQ IC 



GASOLINE TRACTORS 127 

70 per cent of the motor trouble is due to the ignition. A 
resume of the answers sent in to the questionnaire follows: 



Magnetos 


299 


Cylinders and pistons 


61 


Spark plugs 


110 


Clutch 


59 


Gears 


108 


Valves and springs 


43 


Carburetor 


104 


Lubrication 


29 


Bearings 


80 


Starting 


28 



The figures given in each case represent the number of tractor 
owners who gave the part in question as the chief cause of their 
troubles in operation. These figures do not, however, give any 
idea of the relative importance of the parts as sources of trouble. 
Failure of the magneto, or even of a spark plug, brings the 
tractor to a halt, but the trouble may usually be remedied in a 
very short time and no damage is caused, whereas a breakdown 
due to faulty lubrication, or to the failure of the cooling system, 
which is not mentioned at all, will usually involve the loss of 
anywhere from a day to a week besides a heavy repair bill. 

Supply of Spares Necessary. The cost of an ample supply 
of spare parts is small compared with the time that is saved 
when the part most needed is right at hand and can be installed 
without delay, so that a number of spares of the most necessary 
parts should be considered part of the investment and be bought 
at the same time as the machine. L T nless it be an ocean-going 
steamer, there is hardly another piece of machinery that per- 
forms such strenuous service so far from a repair and supply 
base as does the tractor. It would be just as foolish for the 
chief engineer of a steamer to leave port without any spare 
parts in the storeroom and still expect to arrive at his destina- 
tion, regardless of what happened, as it is for a farmer to pur- 
chase a tractor and expect to get through his first, second, or 
any other season of plowing or threshing without vexatious delays 
unless he has on hand spares of the parts most frequently needed. 

Manufacturer's Service Poor. While it would not be just to 
generalize by saying that the service rendered the purchaser by 
every manufacturer of tractors is poor, this is true in many cases 
and must always remain so for the farmer who is located miles 
from the nearest dealer representing i>e factory. It is nothing 
unusual to waste from half a day to a day, telephoning and 

Digitized by VjOOQ IC 



128 GASOLINE TRACTORS 

waiting for a part to be sent out or driving in for it. The 
dealer may be off for the day in some other part of the county, 
making a demonstration or closing a sale, and there may be no 
one in his place of business to render the desired service. Mean- 
while, the machine is standing idle. There are few replacements 
that the experienced driver of a tractor cannot make without 
other assistance than that provided by the usual farm shop, so 
that if the parts are on hand little time will be lost in getting 
the machine under way again. 

Parts Needed. While the make of the tractor in question 
will determine the character of many of the spares that should 
be carried by its owner, there are some that are needed with all 
makes. These are valves, valve springs, and small parts needed 
in connection with the valves, ignitors, or make-and-break plugs 
for low-tension ignition systems, also ignitor trip rods, or rather 
the small parts which compose the fittings of the rod rather than 
the rod itself, since the latter is not subjected to wear. Spare 
connecting cables cut to length and fitted with terminals, whether 
for high- or low-tension systems, will often be found valuable. 
Extra fan belts and spark plugs should hardly be called spare 
parts in this connection since they are absolute necessities at 
comparatively short intervals. Hose connections between the 
motor and the radiator are also in the same class. Where a 
motor is equipped with die-cast main bearings or connecting-rod 
bearings, a spare set will often prove to be worth many times 
its cost in the saving of plowing or threshing time, since even 
well-attended machines do suffer breakdowns from burnt-out bear- 
ings at times. Extra piston rings as well as an extra piston 
and a connecting rod are likely to be called for sooner or later. 
The magneto is a pretty expensive piece of equipment and, more- 
over, it is usually so reliable that it will continue to work season 
after season without giving any trouble. But when it does break 
down, it is sometimes beyond the ability of the tractor operator 
to make the repair. Where two or more tractors are operated on 
a farm and the same magneto is standard on all of them, it 
would pay to invest in a spare, though at any time but the 
height of the season the laying up of one tractor would probably 
not cause any trouble. 



138 



Digitized by VjOOQIC 



GASOLINE TRACTORS 129 

The foregoing discussion has been confined to enumerating 
motor parts or accessories that should be carried as. spares since 
they are common to practically all motors. So far as the rest 
of the machine is concerned, the owner must either learn from 
experience what parts are likely to wear out rapidly and need 
replacement at short intervals, or he must depend upon the 
manufacturer's representative to give him this information. 
Naturally, the maker and his salesmen do not wish to give the 
impression that any of the machine's parts will need replacement 
in a short time, and in a good many instances they are as much 
in the dark as the purchaser is, since jt may be that the model 
has just been placed on the market and there has been no oppor- 
tunity to learn its weak points in actual service. 

Both the time spent in getting information of this kind and 
the money invested in the necessary spare parts will return very 
substantial dividends when the occasion arises to use the parts. 
There are some parts that may never be used, such as a steering 
knuckle. Get the manufacturer's representative to give you a 
frank opinion. Point out your position, when isolated, and do 
not content yourself with his first recommendations. Insist on 
finding out what are the weak parts of every important unit. 
The factory man has a good line on this by the extent of the 
demand for certain replacement parts. It will usually be found a 
paying investment to purchase a stock of almost all of them 
rather than take chances on getting the particular part most 
needed at a time when the tractor is worth a good many dollars 
an hour to you. 

LUBRICATION 

MOTOR LUBRICATION 

Q. What grade of lubricating oil should be used for a slow- 
speed tractor motor; for a high-speed type? 

A. Every responsible tractor manufacturer goes to consider- 
able expense to determine just what grade of lubricating oil is 
best adapted to his own engines. His investigation covers every- 
thing from a chemical analysis and flash test of every grade of 
oil recommended for his use to actual tests in service extending 
over considerable periods of time. The tractor owner should 

130 



130 GASOLINE TRACTORS 

accordingly never use anything but the oil recommended by the 
manufacturer. 

Q. In a motor having any form of splash lubrication, that 
is, one in which part of the supply is carried in the crankcase 
pan, how often should the oil be drained from the crankcase? 

A. The recommendations of different tractor manufacturers 
range all the way from every day to once in two weeks, many 
giving one week as the maximum period of time the same oil 
should be used. 

Q. How often should the oil in a circulating system be 
completely replaced with a fresh supply? 

A. It should be replaced at the intervals given above for a splash 
system since the service demanded of the lubricant is the same. 

Q. Does oil lose its lubricating qualities through use, and 
how can this be determined? 

A. High temperature and pressure completely change the 
character of lubricating oil and destroy its lubricating qualities. 
The lubricating quality of an oil depends upon its viscosity, that 
is, its body, upon which depends its ability to hold apart surfaces 
under pressure by a film of lubricant. Dip the finger ends in 
some old oil from the crankcase and rub together under pressure. 
The oil will have a thin watery feeling and the finger tips may 
be pressed into close contact through it. Try the same experi- 
ment with some fresh oil, and it will be noted that a sliding 
film is formed between the fingers despite the greatest pressure 
that can be put upon them to squeeze it out. 

Q. What influence has the effect of high temperature and 
pressure on the length of time during which the oil should be 
allowed to remain in the crankcase? 

A. Both the temperature and the pressure conditions differ 
widely in different engines so that in some the oil literally wears 
out much faster than in others and should accordingly be replaced 
oftener. The tractor manufacturer has learned from experience 
the proper period of time for his motors, and his recommenda- 
tion is based on a desire to avoid having his customer pay for 
the same experience. 

Q. Next to labor and fuel, lubricating oil is the most 
expensive item of tractor maintenance. Is it really economy to 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 131 

replace what appears to be good oil as often as the tractor 
manufacturer recommends it? 

A. The cost of repairs due to a single breakdown from 
failure of the lubrication would usually buy anywhere from one 
to five or more 50-gallon barrels of oil, without taking into 
account the loss of time due to the tractor being out of service. 
It is the highest form of economy to follow the maker's instruc- 
tions in this respect; if these are to discard the oil at the end 
of every day's service, it will be found far cheaper in the end to 
do so. Many tractor owners do not regard it as necessary to 
clean out the crankcase more than once or twice a season, but 
instead of saving oil they are simply running up repair bills. 

Q. What other causes tend to destroy the lubricating quality 
of the oil? 

A. Another cause is leakage of the fuel past the pistons so 
that the supply of oil in the crankcase is thinned out by the 
gasoline or kerosene. This is particularly true of kerosene, espe- 
cially if the motor be run at a low temperature so that the kero- 
sene vapor condenses into a liquid. The admixture of carbon and 
dirt with the oil also tends to destroy its lubricating quality. 
Compare the color of oil that has been used for some time with 
fresh oil; the difference is due entirely to the foreign matter that 
has become mixed with it. 

Q. What attention does a force=feed lubricator require? 

A. The sight feeds should be watched frequently to note 
whether oil is constantly passing through them or not. To make 
certain of this, dirt should be wiped from the glasses at least 
once a day. While this type of lubrication has the great advan- 
tage of constantly feeding fresh oil to the bearings almost as fast 
as it is consumed, its factor of safety is not so high as that of 
the splash or circulating type. In other words, failure of the 
part is apt to follow immediately upon a stopping of the feed 
since it usually receives no lubrication from any other source. 
The lubricator must accordingly be watched closely and the 
engine stopped at once if any of the feeds has become clogged. 

Q. How often should such a lubricator be supplied with fresh oil? 

A. The maker's instructions may be followed but a still 
better practice is to get into the habit of keeping the lubricator 



141 



132 GASOLINE TRACTORS 

constantly filled; that is, of filling it twice or oftener a day, if 
necessary, rather than waiting until the supply runs low. A 
gage glass on the side of the lubricator shows the amount in it. 
The plunger pumps which force the oil to the bearings will 
always work better when there is an ample supply. 

Q. What other precautions should be taken with a force- 
feed lubricator? 

A. When it is driven by a belt, close watch should be kept 
on the belt to see that it does not become too loose, since any 
slackening of the belt slows down the pumps and supplies less 
oil to the bearings. 

Q. How often should a force-feed lubricator be cleaned out? 

A. Two or three times a season should ordinarily be ample, 
but this will depend to some extent upon the care that is exer- 
cised in handling the supply of oil itself. Unless the oil supply 
is kept in a covered oil tank, more or less dust and other foreign 
matter is bound to find its way into it. The presence of dirt 
in the oil will make itself apparent by clouding the inside of the 
sight-feed glasses, making them difficult to read. Oil having 
visible foreign matter, such as small specks of grit, short ends of 
straw, or chaff, in it should never be put into the lubricator 
without straining, as it is liable to clog the pump valves. 

Q. How is a force-feed lubricator cleaned out? 

A. By disconnecting the leads and flushing it out thoroughly 
with gasoline or kerosene. The leads should be disconnected at 
both, ends and also flushed out, blowing through them to see 
that they are clear from end to end. 

Q. Are some of these leads more apt to clog up than others? 

A. Those that supply oil to the pistons are most likely to 
clog owing to an accumulation of carbon in the ends opening 
into the cylinder. They should be taken off at shorter intervals 
anc^ all carbon removed in the tube itself as well as in the open- 
ing through which the oil passes through the cylinder wall. 

Q. What attention does a circulating system require? 

A. A circulating system requires replenishing of the entire 
supply after washing out at intervals, as directed in the manu- 
facturer's instructions; examination at short intervals of the oil 
pump; and frequent washing off of the oil pump screen. Keep 

Digitized by VjOOQ l6 ' 



GASOLINE TRACTORS 133 

the sight-feed glasses clean and shut down immediately if an oil 
stream fails to appear in any of them (some tractors have but 
one, others several). 

Q. What general precautions should be observed in clean- 
ing out a lubricating system of any type and in handling oil? 

A. Always avoid the use of waste or rags from which lint 
will detach itself in wiping out the crankcase or any part of the 
system, since these threads will invariably clog an oil pump or 
feeder tubes. All cans or other vessels used in handling oil should 
be kept covered to prevent dust falling in them and should be 
wiped clean before using. Dust is simply fine grit, and its pres- 
ence in the oil converts it into a grinding compound which will 
quickly cut away bearing surfaces. 

Q. What other lubrication does the motor require? 

A. This will depend entirely on the type of motor. Where 
it has overhead valves as used on many tractor motors, the rocker 
arm spindles and pin should be oiled at least once or twice a 
day with a hand oiler. This applies as well to any other external 
moving parts not lubricated by the oiling system of the motor. 
The grease cups on the fan and on the pump should be turned 
down at least once a day. Some tractors are equipped with 
gravity oilers for this purpose. 

CONTROL SYSTEM LUBRICATION 

Q. How is the clutch lubricated? 

A. On some tractors it is enclosed in the same housing as 
the motor and runs in a bath of oil. Where it is not housed in, 
grease cups are usually provided on the clutch, and these should 
be turned down at least once a day. No oil should be allowed 
to fall on the facing, as this would reduce the holding power of 
the clutch and cause it to slip. 

Q. What attention is required to keep the transmission 
properly lubricated? 

A. When the transmission is of the enclosed type, running 
in oil, it should be kept filled to the height given in the maker's 
instructions and with the grade of lubricant recommended. Don't 
attempt to use cup grease, or a home-made compound of grease 
and oil or graphite, as the different materials will separate, nor 

143 



134 GASOLINE TRACTORS 

should heavy steam cylinder oil be used, since it contains animal 
fats and will become acid, attacking the steel faces of the gears. 
The pressure between the gear teeth in a transmission is very 
high so that the oil wears out in time and should be replaced at 
intervals of two to three months. Watch the transmission hous- 
ing for leaks and renew felt washers or other provision for pre- 
venting leaks. 

Q. How are open transmission gears lubricated? 

A. Where gears are run without a housing, they are not 
intended to be lubricated and care should be taken to see that 
no oil or grease gets on them as it will hold dirt and grit and 
cause the teeth to wear out much faster. The gears should be 
kept free of mud and dirt, but an oily rag or waste should never 
be used for this purpose. This also applies to the bull pinion 
and gear except where completely housed in. 

Q. What attention is required to lubricate other moving 
parts of the tractor? 

A. Grease cups are usually provided on all other moving 
parts, and they should be turned down as instructed by the 
maker. In some instances the directions are to. screw these cups 
down as often as twice a day; in others, once an hour. 

ENGINE PARTS 

ENGINE BEARINGS 

Q. How long will motor bearings run without developing 
sufficient play to require adjustment? 

A. This will depend largely upon the motor itself and tj^e 
service demanded of the tractor. If it is being run constantly 
with an overload, they will need attention much sooner than 
when the machine is not called upon to carry more than 75 per 
cent of its load for the greater part of the time. In any case 
the bearings should be examined at least once a week; some 
makers recommend that they be tested for looseness as often as 
twice a week when in constant service. 

Q. How can the bearings be tested for looseness? 

A. They should always be examined just after the motor 
has been shut down and is still hot; the amount of play will be 



Digitized by VjOOQ IC 



GASOLINE TRACTORS 135 

greater when all the parts are cold but some of this will be taken 
up by the thickened oil film then present and their condition 
cannot be determined as satisfactorily. The connecting-rod bear- 
ings are the first to show signs of looseness. Take the handhole 
covers off the crankcase and turn the motor until two of the 
connecting-rod ends are close to the openings. If there is much 
play, it will be evident upon grasping the connecting rod and 
attempting to lift it, but this amount would usually cause a 
knock in operation. Take a small bar and pry the bearing 
upward from below, keeping the other hand on the rod to detect 
any movement. Do not confuse the side play of the bearing 
with looseness of the bearing itself as a small amount of side 
movement ?.s allowed on all connecting-rod bearings. Apply this 
test to the other two connecting rods also. A bar may also be 
used to detect any looseness of the main or crankshaft bearings. 

Q. Will it do any harm to allow a certain amount of play 
in these bearings? ' 

A. Nothing will be apt to run up a big repair bill quicker 
than running the motor with the bearings too loose. Every 
reversal of movement pounds the crankshaft and in time will 
cause crystallization of the steel with consequent breakage of the 
shaft. The resulting vibration is also detrimental to every other 
part of the motor. 

Q. How are the bearings adjusted when a test reveals 
play in them? 

A. Most motor bearings are provided with shims, that is, 
small strips of metal placed between the halves of the bearing 
and through which the bolts pass to hold the bearing together. 
Take off one or more shims on each side of the bearing and 
screw down the nuts again tightly. To obtain a proper adjust- 
ment, you must be able to set up these nuts as far as they will 
go without binding the shaft. Open the pet cocks or the com- 
pression release, where one is provided on the engine, and try 
the adjustment by cranking the motor by hand. It will be very 
difficult to turn the motor over if the bearings are too tight. 
They should be adjusted so that the motor turns easily, indi- 
cating that there is sufficient space between the bearing halves 
and the shaft to permit the formation of an oil film between 



Digitized by VjOOQ IC 



136 GASOLINE TRACTORS 

them. The shaft should be tested for play, as already described, 
to prevent making the adjustment too loose. 

Q. When a bearing is too tight, is it good practice to ease 
off the nuts and let the shaft run that way? 

A. A bearing is not properly adjusted unless the nuts can 
be set up hard on the bearing caps, all adjustments being made 
by removing or re-inserting shims, or laminations of metal only a 
few thousandths of an inch thick. One or two shims should be 
removed from each side at a time and the adjustment tested. 
Care must always be taken to see that the bearing cap is replaced 
on the bearing from which it was taken and that it is put back 
in the same way. 

Q. Is it ever necessary to adjust the piston-pin, or wrist- 
pin, bearing? 

A. This is the bearing which holds the upper end of the 
connecting rod in the piston and if the motor is properly lubri- 
cated with clean oil, it will seldom require any attention. In 
some motors the pin is held fast in the sides of the piston and 
the connecting rod moves on it, and shims are provided on the 
connecting-rod bearing for adjustment. In others the upper end 
of the connecting rod is clamped fast to the pin, and the pin 
moves in bronze bushings in the sides of the piston or bears 
directly on the piston walls. Allowing the big-end connecting- 
rod bearings and the crankshaft bearings to become too loose so 
that the motor knocks is the chief cause of lost motion in the 
wrist-pin bearing. Where the pin bears in the piston walls this 
may wear the holes out of round so that they have to be rebored 
and bushed to make a good bearing. 

Q. When the connecting rod or crankshaft bearings of a 
motor require adjustment at frequent intervals, what is the cause 
of the trouble? 

A. The cause is faulty lubrication: failure to clean out the 
crankcase at the proper intervals, with the result that the oil 
loses its lubricating qualities and the dirt that becomes mixed 
with it cuts away the bearing surfaces. 

Q. Where bearings have become worn to the point where it is 
no longer possible to adjust them properly, is it practical for the 
average operator of a tractor to replace them with new bearings? 



146 



Digitized by VjOOQIC 



GASOLINE TRACTORS 137 

A. It is not practical unless he has had experience in the 
work, since it requires accurate lining up and scraping in of the 
bearings to a close fit. Unless this is carried out properly, such 
heavy stresses will be imposed on the crankshaft that it will 
break sooner or later. Therefore it is poor economy to attempt 
this repair without actually having had experience in making it; 
it is one of those things that cannot be learned from an instruc- 
tion book. It is necessary to see it done in the shop more than 
once and the first attempt should be made under the supervision 
of one who has had experience. 

VALVES 

Q. What attention is required to keep the valves in good 
operating condition? 

A. The valve stems must be lubricated one or more times 
a day, except on motors provided with special means for doing 
this automatically. The clearance between the valve tappet and 
push rod, or between the end of the rocker arm and the valve 
stem, depending upon the type of motor, must be adjusted at 
frequent intervals and the valves themselves must be ground as 
often as is necessary to keep them tight. 

Q. Why Is adjustment of the clearance necessary, and 
what should this be? 

A. The constant hammering of the tappet or rocker arm 
against the valve stem tends to increase this clearance as well as 
to wear away the parts, thus increasing the distance. The greater 
this distance is the less the valve will lift when operated, so that 
less fuel is admitted on the intake stroke and some of the exhaust 
gases are left in the cylinder on the exhaust stroke, thus cutting 
down the power. This clearance should be just sufficient to 
allow the valve to close. completely under the pull of its spring 
when the tappet or rocker arm is released by the cam. It should 
be tested and adjusted w'th the motor hot, since, if made very 
close when cold, the expansion of the parts is apt to prevent 
the valve from closing properly. An ordinary visiting card or a 
piece of tin plate makes a good gage; it should be possible to 
slip this between the tappet and stem easily. In any case the 
clearance should not exceed -gV inch. 

14T 



138 GASOLINE TRACTORS 

Q. How often should the valves be ground? 

% A. When a tractor is being used ten hours a day and six 
days a week, they will doubtless require grinding once every four 
to six weeks, depending more or less on the motor itself; some 
motors run very much hotter than others and in some the pro- 
vision for cooling the exhaust valve is inadequate, so that more 
frequent attention is necessary. 

Q. How may the valves be tested for leakage without 
taking the motor down? 

A. Turn the motor over by hand about one-third of a revo- 
lution, until two of the pistons are within an inch or two of the 
upper dead center. At this point the pressure in the cylinder 
that is then on the compression stroke should be highest. Hold 
the piston up against this pressure, just exerting sufficient pull 
to cause the piston to move if the compression leaks away. In 
a motor that is in good condition, there should be no perceptible 
movement due to leakage in the course of two or three minutes, 
and if the pull of the hand is slackened, the piston should tend 
to push the starting crank down again under the influence of 
the pressure in the cylinder. Apply the test to each cylinder in 
turn and any difference in the compression-holding power of the 
different cylinders will be noticeable. 

Q. When the usual adjustment of the clearance does not 
correct a loose and noisy valve action, what is apt to be the 
cause of the trouble? 

A. The pin of the cam roller has probably worn so that 
there is considerable lost motion between the roller and the pin 
on which it turns. The only remedy is to replace the roller 
and pin or maybe the tappet complete. Any lost motion at 
this point permits the roller to move upward the distance repre- 
sented by the wear before the tappet itself can lift. While the 
play at any one point may be very small, when it is increased 
by an equivalent amount at two or three other points, the total 
is sufficient to reduce the effective valve opening considerably, 
with a corresponding decrease in the power. When nfew parts 
are not readily obtainable, this condition may be remedied by 
boring out the holes of the cam roller and the rocker lever and 
fitting them with bushings. 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 139 

Q. When grinding valves, is it necessary to continue the 
operation until the entire valve and seat have taken on a polish? 

A. No; the operation may be considered complete when 
both the valve and the seat are smooth all around and com- 
pletely free from any sign of pitting. A polished surface may 
give a little closer fit, but the difference is not enough to com- 
pensate for the time necessary to produce it. The grinding 
operation should always be finished by the use of the fine grind- 
ing compound. 

Q. In case a motor has been allowed to run until the valve 
seats have become very badly pitted, is it necessary to cut these 
down by grinding alone? 

A. No; a valve-seat reaming tool should be employed for 
cutting away the metal until the pitting has almost disappeared, 
and the remainder of the operation should then be carried out 
by grinding in the usual manner. No more metal than necessary 
should be removed with the reamer as cutting too deep will 
simply shorten the life of the cylinder casting. Valves are made 
in two standard tapers, 45 degrees and 60 degrees, and care 
must be taken to see that the angle of the reamer blades corre- 
sponds to that of the valve seat before beginning to cut. 

Q. Is there any way of testing the tightness of the valves 
before putting them back into the motor? 

A. When the valves are in cages, they may be tested by 
pouring some gasoline into the cage and noting whether it leaks 
past the valve or not. 

Q. Does a rapid loss of compression under such a test 
always definitely indicate that the valves are at fault? 

A. No; the piston rings may be worn or the lubrication 
may be poor, so that there is not a good compression seal in 
the cylinder. To definitely ascertain the trouble, take out the 
spark plugs and pour an ounce or two of heavy cylinder oil into 
each cylinder. 'Turn the motor over fifteen to twenty times 
with the plugs out to work this oil down on the pistons, replace 
the spark plugs and repeat the test as first described. Failure 
to hold compression will then mean poorly seating valves almost 
invariably, since, with a fresh oil seal, even loose piston rings 
will hold compression when the motor is being turned over by 



149 



140 GASOLINE TRACTORS 

band. The necessity for putting in this oil indicates that the 
oil in the crankcase or the circulating system needs renewing. 
This test for loss of compression should be carried out with the 
motor cold. 

Q. What is the best method of grinding the valves? 

A. With a valve-in-head type of motor, take the valve 
cages over to the bench so that there is no risk of getting any of 
the grinding compound into the cylinders. Use nothing but the 
specially prepared grinding compound designed for this purpose; 
ordinary emery and oil should never be employed as it will score 
the valve and its seat. When a special valve grinder is not at 
hand, a screw driver bit in an ordinary brace makes the best 
grinding tool. Smear some of the compound on the valve, drop it 
on its seat and turn it first one way and then the other, making 
about a quarter turn in each direction without exerting much 
pressure. When the compound has been squeezed out, put in 
more and continue the operation, repeating this for fifteen to 
twenty minutes. Wash the valve and seat off with kerosene and 
examine to see if all signs of pitting have been removed and the 
valve has a bright uniform band around its entire circumference. 
The presence of any breaks in this ring indicates low spots and 
calls for further grinding. Never turn the valve completely 
around when grinding, making only a quarter turn, since the com- 
plete turn will score the seat. Be careful to flush of! every trace 
of the grinding compound with kerosene when through to prevent 
any trace of it getting into the cylinder. Otherwise, the engine 
will be ruined. Where the valves cannot be taken away from the 
motor for grinding, the greatest care must be exercised to prevent 
any of the compound from getting into the cylinders or down into 
the valve guides. 

Q. Why is it necessary to grind the valves at such short 
intervals? 

A. The exhaust valves in particular are subjected to exceed- 
ingly high temperatures that pit the metal face of the valve. 
Once this pitting starts, it proceeds rapidly and if the valves are 
allowed to run too long without grinding, these pits in the valve 
face will be so deep that new valves will be necessary. They will 
also be deep in the valve seat with the result that a correspond- 



160 Digitized by G00gle 



GASOLINE TRACTORS 141 

ingly longer time is required to grind them out. By grinding at 
the proper intervals, only fifteen to twenty minutes will be 
required for each valve, whereas if they are allowed to run too 
long, it may take an hour or more to get each valve and its seat 
into proper condition again. The motor will also run very much 
better and deliver more power if the valves are kept in good con- 
dition. 

Q. What is the cause of a valve leaking very badly at 
times? 

A. Hard particles of carbon from the cylinder may lodge in 
the pitted face of the seat or valve and prevent if from closing 
tightly. Even though the valve be held off its seat only a few 
thousandths of an inch, it cannot hold any compression. 

Q. What is the cause of a valve binding so that it will hot 
operate? 

A. Worn valve guides will sometimes permit sufficient side 
play to cause the valve stem to become bent. Lack of lubrication 
and an accumulation of dirt and carbon in the valve guide will 
cause the valve stem to expand to a point where it binds hard 
and fast in the guide. 

Q. What causes a valve head to warp so that the valve 
must be replaced? 

A. It may be caused by overheating of the motor due to 
partial failure of the cooling system, such as may be caused by a 
slipping fan belt, trouble with the circulating pump, shortage of 
water in the system, or the clogging of some of the pipes or the 
radiator. An accumulation of sediment or scale in the jackets or 
the radiator may have the same effect. 

Q. Do valve springs ever need replacement? 

A. In the course of a season's use, the temper may be 
drawn sufficiently to make the valve action sluggish, particularly 
in a motor that runs very hot, but ordinarily the valve springs do 
not often need replacement. 

Q. Is it ever necessary to check the valve timing of the 
engine? 

A. It is never necessary except in reassembling the engine 
after it has been taken down. Since the camshafts are made with 
the cams integral, no relative movement of the cams is possible 



151 



142 GASOLINE TRACTORS 

and it is only necessary to time one cylinder. Most engines have 
reference points by which the valve timing may be checked when 
reassembling the engine. 

PISTONS 

Q. What attention do the pistons require? 

A. The piston rings will wear to such a degree that the 
pistons no longer hold the compression and there is a substantial 
falling off in the power. 

Q. How often should it be necessary to replace the piston rings? 

A. This will depend entirely upon the care that is taken to 
keep dirt out of the lubricating oil and to prevent its entrance to 
the motor through the carburetor. If the oil is handled carelessly, 
containers being allowed to stand uncovered and a film of dust 
settling on them, or if the carburetor is not provided with an air 
cleaner, a great deal of grit will find its way into the motor and 
will grind the piston rings down rapidly and also the bearings. 

Q. How may the pistons be tested for tightness? 

A. The valves being in good condition, preferably recently 
ground, the test may be made as previously described for testing 
the valves; or, with the handhole plates off the crankcase, have an 
assistant turn the motor over slowly and note whether there is any 
sound of air blowing down past the pistons into the crankcase. 
Put a few ounces of fresh oil into each cylinder through the spark 
plug openings, replace the plugs, and repeat the test. Loss of 
compression may be due entirely to poor lubrication. Drain the 
crankcase, wash out with kerosene, and replenish the oil supply; 
and test in the same manner. 

Q. Is wear of the piston rings the only cause for loss of 
compression, aside from pitted valves? 

A. An accumulation of carbon under the piston rings may 
be holding the piston ring joints apart or the latter may have all 
worked into line so that the pressure is escaping through them. 
If, with good tight valves, there is still a loss of compression after 
putting fresh oil into the cylinders, i£ is an indication that the 
piston rings need attention. 

Q. Does the compression fail in all the cylinders equally, or 
is one of the cylinders likely to be worse than the rest? 

152 



GASOLINE TRACTORS 143 

A. The wear is likely to be uneven, so that one or two of 
the cylinders will be found very much worse than the rest. Some- 
times only one cylinder will fail to hold compression. Test in the 
same manner as described for the valves, pulling the crank up 
very slowly to note the resistance offered by each piston in turn 
as it comes up on the compression stroke. It may be found much 
easier to move one of the pistons than the others. When this is 
the case, it will be necessary to fit new rings on that piston. 

Q. How are new piston rings fitted? 

A. Oversize piston rings are supplied for this purpose. 
They are slightly larger (a few thousandths of an inch) than those 
originally supplied with the motor in order to compensate for the 
wear of the cylinder. Take the old rings off by inserting thin 
strips of steel (old table-knife blades or discarded hack saws are 
excellent for the purpose) at three or four points around the piston 
and under the ring. Scrape and wash out all carbon and gummed 
oil in the slots. Do not use a file for this purpose. First try the 
new rings by fitting them in the cylinder, which operation will 
show how much will have to be taken off to allow them to enter 
the bore. They must be small enough to insert an inch or two 
into the cylinder, since it is turned somewhat larger for a short 
distance at the end. If the rings are too large, take a few cuts 
with a fine file across the faces of the joint, being careful to keep 
the surfaces square and parallel. Very little must be taken off 
each time and the ring tried in the cylinder again. The job must 
be carried out with painstaking care as unless it is properly done 
the new rings will be no better than the old ones. When they 
have been properly fitted, use the same strips to place them on 
the piston, care being taken not to spring the rings out of round 
in putting them on. 

Q. When fitting rings in the cylinder as a preliminary to 
putting them on the piston, should the break come together for a 
good fit? 

A. No; allowance must be made for the lengthwise expan- 
sion of the ring due to the high temperature, and this allowance 
must be greater for the top ring than for the lower ones as it 
becomes hotter. Depending upon the diameter of the cylinder, 
it is customary to allow xgoo to tooo inch between the ends of the 



153 Digitized by G00gle 



144 GASOLINE TRACTORS 

topmost ring and y^hr to tHtt inch for the other two. Bearing 
shims are often stamped with the thickness in thousandths of an 
inch and may be used as a gage. Unless this allowance is made, 
the expansion of the ring will cause it to bind against the cylinder 
wall and may cause scoring. 

Q. Must the piston ring be a tight £t In the piston slot? 

A. Allowance for expansion must also be made here. After 
scraping the piston slots free of carbon and washing them out 
with kerosene so that they are perfectly clean, insert the ring and 
see that it turns freely in the slot. A piece of coated catalog 
paper has a thickness of ttAht to Tiftnr inch and it should be possi- 
ble to insert a piece of this paper between the ring and the slot. 
If the rings are too tight they will bind on the piston and cause 
damage as mentioned above. Unless they can be moved freely in 
the slots, they will have to be made smaller by taking metal off 
the bottom edge of the ring. Smear some valve grinding com- 
pound on a flat metal plate or a smooth piece of hardwood plank 
and rotate the ring in this under pressure with the hand. Be sure 
to wash off all traces of the grinding compound before trying on 
the piston again. 

Q. Do the pistons themselves ever have to be replaced? 

A. The same condition that causes rapid wear of the piston 
rings, that is, dirt in the lubricating oil, will also cause equally 
rapid wear of the pistons. When this wear amounts to tHtf to 
jibs inch, the piston will rock on the piston pin in the cylinder 
and produce a distinctive noise, known as piston slap, which can- 
not be traced to any other cause. At first, it is likely to be attrib- 
uted to a loose bearing, and as it increases it will greatly resemble 
a bearing knock. When one piston reaches this stage, it is better 
to replace all of them with oversize pistons. The cylinders should 
be examined carefully for scoring and tested to see if they have 
worn out of round as it may be necessary to rebore them or to 
replace the cylinder casting to make a good job of it. 

Q. Can the pistons be tested for looseness without taking 
the motor down when a knock cannot be traced to any other 
cause? 

A. The amount of wear that will cause considerable piston 
dapping is so small that it would be difficult to detect it without 



.Google 



Digitized by VjOOQI 



GASOLINE TRACTORS 145 

having the cylinder and piston on a bench where the fit can be 
examined closely. The average driver would never attribute the 
loud knocking caused by a loose piston to the apparently slight 
amount of play that i3 revealed when the piston is examined. 

Q. What causes besides dirt in the lubricating oil will 
bring about rapid wear of the pistons or scoring of the cylinders? 

A. Other causes are the use of a poor grade of oil, using the 
same oil too long, or any other condition that results in inefficient 
lubrication, such as overheating due to partial failure of the cooling 
system. Unless there is a good oil film between the piston and 
the cylinder, the metal comes into actual contact and scoring fol- 
lows. Too thin an oil will be burned away by the heat of the 
explosion as fast as the film is formed on the cylinder, while too 
heavy an oil may not reach the upper end of the cylinder bore 
owing to failure to pass the piston rings. Worn piston rings will 
permit particles of carbon from the combustion chamber to work 
between the piston and the cylinder wall. Partial failure of the 
lubrication system, such as the clogging of an oil lead in a force- 
feed system, the clogging of the screen or of the pump in a circu- 
lating system, or an insufficient supply of oil in a splash system, 
will result in scoring. 

Cylinder scoring may be due to the piston ring binding 
owing to failure to allow for expansion in fitting or to the piston 
sticking owing to an accumulation of carbon under it. The wrist 
pin may become loose and move endways so that it scrapes against 
the cylinder wall; or in assembling the piston and connecting rod, 
the wrist pin may be so placed that it presses the piston unevenly 
against one side of the cylinder. Carelessness in valve grinding 
that results in some of the compound getting into the cylinder will 
cause serious scoring sooner than almost anything else. 

CARBURETOR 

Q. What attention does the carburetor need? 

A. It should be drained at frequent intervals to remove the 
accumulation of sediment. Care should be taken to prevent dirt 
from getting into the fuel, and the latter should be strained as it is 
poured into the tank. In making needle-valve adjustments, the 
needle must never be screwed down hard on its seat, since this is 



155 



Digitized by'GoOgle 



146 GASOLINE TRACTORS 

likely to turn a shoulder on it so that proper adjustments cannot 
be made with it. 

Q. When the carburetor floods, what is the usual cause of 
the trouble? 

A. The usual cause is dirt lodging under the needle valve in 
the float chamber. Where a hollow copper float is used, it may 
have sprung a leak, causing it to sink. 

Q. How should the carburetor be adjusted to give the maxi- 
mum power with the most economical fuel consumption? 

A. Definite instructions covering every make of carburetor 
cannot be given, but the same principles can be applied to all. 
With the motor running, cut down the fuel supply gradually until 
the motor begins to run irregularly or to miss. The fuel mixture 
is thus made leaner, and in some cases the motor will back fire 
through the carburetor when the mixture becomes too lean. 
When the point of adjustment has been found at which the motor 
is not getting sufficient fuel, turn back slightly until just enough 
fuel is being supplied to permit it to idle regularly. This is 
termed the low-speed adjustment and some carburetors have no 
other, that is, only the fuel supply can be regulated. Others have 
a high-speed adjustment as well; this controls the air supply and 
takes the form of an adjustable auxiliary air valve. Speed the 
motor up and release the tension of the auxiliary air valve spring 
until the point is reached where too much air is being admitted 
and the mixture again becomes too lean. Then turn back slowly 
until as much air is being admitted as is possible without causing 
irregular operation. 

Q. Does the working of any other part of the motor influ- 
ence the carburetor adjustment? 

A. Unless all other parts of the motor are in good working 
condition, it will be found impossible to make a satisfactory car- 
buretor adjustment. Valves in need of grinding, excessive clear- 
ance between valve tappets and stems or rocker arms, worn piston 
rings or pistons, and worn valve guides will all influence the adjust- 
ment of the carburetor. Air drawn in through worn valve guides, 
a leaky intake manifold, or a leak at the throttle valve of the 
carburetor will weaken the mixture and make it too lean, so that 
the motor loses power and overheats. With the motor running, 



156 



GASOLINE TRACTORS 147 

take a squirt can and put some gasoline on the intake manifold 
gaskets and around the valve stems and note whether it is drawn 
in or not. New gaskets will remedy trouble of this nature at the 
manifold. Whenever the manifold has to be taken down, it is 
always better to replace the gaskets, since it is difficult to make 
used gaskets tight. 

Q. The float valve and needle adjustment being in good 
condition, what is the cause of the trouble when a regular flow 
of fuel cannot be obtained at the nozzle in the mixing chamber? 

A. The supply line may be partially clogged or the vent hole 
in the top of the carburetor may be stopped up. This is a small 
opening designed to admit air in order that there may be atmos- 
pheric pressure on the fuel in the float chamber. If this clogs up, 
a partial vacuum is formed. In a gravity system the air vent on 
the tank may have become stopped up and the fuel will not flow 
to the carburetor owing to the lack of atmospheric pressure on top 
of the supply. In a pressure or a vacuum tank supply system the 
trouble may be with the pump, or with loose joints, or with the 
tank itself. 

Q. When difficulty is experienced in making a satisfactory 
low-speed adjustment, what is likely to be the cause? 

A. The needle valve may have been forced down on its seat 
so that a burr or ring has been formed on the needle. The latter 
should be taken out and repointed. 

Q. Is an air cleaner indispensable in connection with a 
tractor carburetor? 

A. It will save its cost and the time required to attend to it 
many times over. Without it, pistons, rings, and bearings will 
grind out very rapidly, and trouble will be experienced with 
accumulations of carbon, more than half of which will be nothing 
more nor less than dirt drawn in through the carburetor. 

Q. What attention does the air cleaner require? 

A. Frequent cleaning is the only attention needed. When 
the cleaner is of the dry-air type, the engine should always be 
shut down before emptying it. If it is a washer type, see that it 
is constantly supplied with plenty of water. Clean out either 
type twice a day or oftener, if necessary, rather than wait until it 
is fulL Analyses of carbon accumulations taken from automobile 

157 Digitized by G00gle 



148 GASOLINE TRACTORS 

cylinders have shown them to consist of 65 per cent, or more, of 
road dirt. 

Q. How can an over-rich mixture be detected? 

A. Note the color of the exhaust from the muffler. The 
presence of black smoke indicates that too much fuel is being fed; 
blue smoke, too much lubricating oil; and grayish-white smoke, 
poor combustion of kerosene usually due to an excess of water. 
An over-rich mixture, particularly when kerosene is being used, will 
cut the lubricating oil from the cylinder walls and cause scoring 
unless remedied. 

Q. What is the object of feeding water with the fuel? 

A. To assist in keeping the temperature of the engine down 
to the proper point for satisfactory working. The steam generated 
rapidly absorbs a great deal of the heat and has the further 
advantage of preventing the formation of carbon in the cylinders. 
It also causes better combustion, particularly in the case of kerosene. 

Q. Should water be fed with the fuel regardless of the 
grade of oil employed? 

A. Little or no water is necessary when using gasoline, but 
the majority of motors will not operate satisfactorily on kerosene 
without it. 

Q. Is there any danger of feeding too much water, par- 
ticularly when the motor is running very hot and appears to 
need it? 

A. Excess water fed with the fuel is liable to lower the 
temperature to the point at which kerosene recondenses to a 
liquid; in such a case considerable of it works its way past the 
pistons and down into the crankcase. This destroys the film of 
lubricant on the cylinder walls and is liable to cause damage, not 
alone to the cylinders themselves but likewise to the bearings; 
thinning the oil in the crankcase destroys its lubricating qualities. 
If the motor appears to be getting too hot, the trouble should be 
remedied by locating the fault in the cooling or the lubricating 
system and not by attempting to overcome it by increasing the 
amount of water fed. 

Q. What indication is there of excessive water in the fuel? 

A. A grayish white smoke will appear at the exhaust indi- 
cating that the kerosene is not being completely burned in the 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 149 

cylinders. Cut down the water supply very gradually until the 
smoke disappears, the motor being kept running at a good speed, 
since if run too slowly on kerosene the combustion of the latter 
will not be complete owing to the drop in temperature. 

Q. Are all tractor motors provided with hand-controlled 
apparatus for feeding water? 

A. No; some carburetors are designed to feed water auto- 
matically as it is needed, while in others the use of a wet air 
cleaner is depended upon to supply the proper amount of water 
required. 

Q. Where hand control is provided, should the water be 
fed as long as the engine is running? 

A.- It is better to shut it off five minutes or so before the 
motor is to be stopped, and the fuel should be switched from kero- 
sene to gasoline at the same time, as this will leave the motor in 
better condition and facilitate restarting. 

Q. What precautions should be taken with the water sup- 
plied for this purpose? 

A. Clean rain. water should be used, and it is well to strain 
it through two or three thicknesses of cloth to prevent the entrance 
of any dirt. 

COOLING SYSTEM 

Q. When the engine overheats despite the fact that the 
cooling system is working properly, what is, the cause of the 
trouble? 

A. It may be due either to an over-rich or an over-lean 
mixture. In either case combustion is slow instead of taking the 
form of the explosion required to produce the maximum power. 
The mixture continues to burn throughout the stroke and in the 
exhaust passages' and muffler. Flame issuing from the exhaust is 
an indication of this condition. The ignition may be retarded too 
far and bring about the same condition. 

Q. What are some of the causes of failure of the cooling 
system? 

A. Among the causes are the following: insufficient water 
supply; fan belt slipping; pump running too slow when driven by a 
belt; insufficient lubrication; leaks in radiator or at pump packing 
permitting water to escape or air to enter; and clogging of radia- 

16f Digitized by G00gk 



150 GASOLINE TRACTORS 

tor, circulating pipes, or water jackets with an accumulation of 
sediment. The cooling system should be drained at frequent 
intervals and flushed out with clean water. An accumulation of 
carbon in the cylinders will also cause the engine to overheat and 
if allowed to become very bad, will cause preignition, which 
imposes very heavy stresses on all moving parts of the engine. 

Q. When hard water has to be used in the cooling system 
and scale forms, how can this be removed? 

A. A strong soda solution made by adding several pounds of 
common washing soda to enough boiling water to fill the system 
should be used for a day or so in place of ordinary water. The 
system should then be drained and flushed out. The use of rain 
water will prevent the formation of scale. Particles of iron rust 
in the water when the system is flushed should not be confused 
with scale; these will always be found, even if the system is 
drained every day. 

Q. Do the flexible-hose connections ever cause any trouble? 

A. The inner plies of the hose sometimes become detached 
owing to the high temperature of the cooling water and either 
partially or wholly clog the passage. The passage is liable to 
become wholly clogged with the pump type of circulation owing to 
the much smaller diameter of the hose used. To guard against 
trouble of this nature, use nothing but the hose connections sup- 
plied by the manufacturers as replacements since this hose is 
specially made to withstand hot water. Ordinary hose will dis- 
integrate rapidly when employed for this purpose and should 
never be so used except to tide over an emergency, being replaced 
with a new connection as soon as possible. 

Q. Is partial or total failure of the cooling system the only 
cause of overheating? 

A. No; there are numerous other causes of overheating. 
The motor may be run with the ignition retarded; the lubrication 
may not be efficient; or carbon may have accumulated in the 
combustion chambers, as pointed out in a previous answer. 

Q. How can carbon be prevented from accumulating in the motor? 

A. After the motor has been shut down for the day and is 
very hot, take out the spark plugs, turn the motor over by hand 
until all the pistons are at approximately the same height, and 



160 



Digitized by VjOOQ IC 



GASOLINE TRACTORS 151 

pour into each cylinder about an ounce of kerosene, letting it 
stand this way over night. Do not use more than this amount of 
kerosene (a tablespoon will hold about an ounce) on the theory 
that if a little does good, more will do better, since more kerosene 
will cut the lubricating film off the cylinder walls and thin the oil 
in the crankcase. 

Q. How can the fan belt be kept ingood condition? 

A. Make adjustments only when the motor is hot and do 
not put any more tension on the belt than is necessary to prevent 
slipping. A belt that is set up too tightly will wear very quickly 
besides imposing undue stresses on the pulley bearings. Keep the 
leather soft by applying neatsfoot oil from time to time. 

Q. How often should the radiator and cooling system be 
drained? 

A. Two or three times a season are sufficient in summer if 
clean rain water is being used and it is strained before being put 
into the radiator. In winter it will be found better practice to 
drain the entire system every night rather than to depend upon 
an anti-freezing solution, since the latter lowers the boiling point 
of the water to such an extent that it is likely to boil away. In 
any case, if alcohol is used in the anti-freezing solution, it is 
likely to boil out of the water, so that the latter cannot be left in 
over night with safety. Some tractors are cooled by oil, and in 
cold weather it is necessary to thin this oil with kerosene before it 
will circulate freely. 

Q. When it is discovered that a considerable quantity of 
the water has boiled away and the motor is very hot, is it good 
practice to fill up with cold water immediately? 

A. This should not be done, particularly in winter, as the 
fresh supply is likely to be very cold and the sudden contraction 
would impose severe stresses on the radiator joints, starting leaks. 

Q. What attention does the pump of a circulating system 
require? 

A. See that the glands are kept tight. The appearance of a 
drop of water at the gland indicates the beginning of a slow leak. 
Give the gland nut a partial turn to tighten it; if water still 
appears, it will be necessary to repack the stuffing box. Use oil- 
soaked cotton wick or graphite packing. 

161 



162 GASOLINE TRACTORS 

HORSEPOWER RATINQS 
Q. Why are tractors rated as 10-20, 16-30, etc., always 
giving two horsepower ratings? 

A. Tractors are designed to be used for belt as well as for 
field work. In doing the latter, the tractor must use a substantial 
percentage of its power to move itself. . The lower rating accord- 
ingly expresses the amount of power available for plowing. When 
standing, as in performing belt work, the only losses are caused by 
whatever transmission gearing is interposed between the engine 
and the belt pulley, so that almost the entire output of the power 
plant is available for driving other machinery. 

Q. What constitutes an overload, and why do all manu- 
facturers warn the tractor user so strongly against subjecting 
the machine to overloads? 

A. Considerable confusion exists as to the meaning of the 
term horsepower. For a few minutes, as in pulling out of a hole, 
a heavy draft horse is capable of exerting COO to 800 pounds draw- 
bar pull, which is the equivalent of more than 1 hp., but the 
same, horse cannot exert much more than an average of 100 pounds 
drawbar pull at a speed of three miles an hour in hauling a load 
all day. The fact that a tractor having a field rating of 16 hp. 
may be pulled out of a bad place by three heavy horses does not 
indicate that the team is capable of doing as much work as the 
machine. The animals can only exert this much power for a very 
short period. The tractor will generate an amount of power at 
the drawbar equivalent to fourteen or fifteen horses at the usual 
plowing speed and will keep it up all day. A load such as 
twelve horses could haul all day would represent the practical 
working maximum for such a machine. A heavier load than this, 
apart from emergencies which call for all the power the machine 
can produce for only a very short period, would represent an over- 
load for that tractor. In other words, the tractor should not be 
steadily subjected to & load amounting to more than 75 per cent 
of its capacity. Manufacturers warn tractor owners against over- 
loading their machines because tractors will wear out very quickly 
under the excessive strain and will nol give satisfactory service 
during the machine's greatly reduced useful life. Regardless of 
the plow rating of the tractor, as for instance, three-plow or four- 



162 



Digitized by VjOOQIC 



GASOLINE TRACTORS 153 

plow, the number of plows used should depend upon the nature 
of the soil. When the latter is very heavy, or the plowing has to 
be done on an up grade, fewer plows should be used. More and 
better work will be done by not subjecting the tractor to any 
greater load than it can pull without exerting more than 75 per 
cent of its power. 

ENQINE TROUBLES 
FAILURE TO START 

Q. What are some of the commoner causes of failure to 
start? 

A. Over 95 per cent of all failures to start are due to either 
lack of fuel or lack of the spark to ignite it. Part of the remain- 
ing 5 per cent are due to the failure of the two to come together 
at the right time, while the rest may be put down to faults hav- 
ing no connection with either the carburetor or the magneto. 

Q. Does lack of fuel in this connection mean an empty 
tank and nothing more? 

A. While a great deal of energy has been expended to no 
good purpose in trying to start an engine that was connected to 
an empty gasoline tank, lack of fuel implies a great deal more 
than that. It does not do much good to have a full tank unless 
the fuel is actually getting into the cylinders every time the 
engine turns over. There may be a stoppage between the tank 
and the carburetor or between the latter and the cylinders. A 
plugged air vent either at the tank or at the carburetor will pre- 
vent the liquid fuel from reaching the carburetor nozzle. A 
stopped-up carburetor nozzle will not vaporize any fuel, while a 
broken throttle connection which leaves the throttle closed will 
not permit any spray from an open nozzle to reach the motor, or 
at least not enough to render starting easy. Air leaks at the 
carburetor, the manifold, or the valve stems will weaken the 
mixture considerably. 

Q. Is it not as hard to start with too much fuel as with 
too little? 

A. Flooding the cylinders makes starting very difficult, and 
when this has occurred, the only remedy is to shut off the supply 
entirely and crank the motor for a few minutes to clean out the 

Digitized by VjOOQ IC 



154 GASOLINE TRACTORS 

cylinders. Priming too freely is a bad practice, since the liquid 
gasoline cuts the lubricating oil from the cylinder walls and 
destroys the compression to such an extent that in an old engine 
it is next to impossible to start even though the fuel and the 
spark come together in the right place at the right time. This is 
one of the unspecified causes responsible for part of the 5 per 
cent of the failures to start mentioned previously. There will be 
a weak explosion every time a cylinder should fire, but not 
enough power will be produced to cause the engine to take up its 
cycle and run. 

Q. When the cylinders have been flooded by over-priming 
with gasoline, what should be done? 

A. Close the throttle and open the air valve or choker, so 
that no gasoline is drawn through the carburetor. Take out the 
spark plugs and put 2 or 3 ounces of heavy cylinder oil into each 
cylinder. Replace the plugs and turn the motor over for two or 
three minutes with the ignition off. 

Q. Has the position of the throttle lever any effect on the 
fuel supply at starting? * 

A. Some engines can only be started readily with the throttle 
at a certain position, usually not more than one-third open and 
sometimes considerably less. On a cold morning opening the 
throttle too far is liable to allow too much gasoline in liquid form to 
find its way into the cylinders, so that the effect is the same as 
that of over-priming or flooding. 

Q. How should an engine be primed? 

A. Gasoline should be carried in a squirt can for this pur- 
pose and not more than a teaspoonful should be squirted into each 
cylinder through the pet cocks. If the engine does not start after 
priming two or three times, look for some other cause of fuel or 
ignition failure. If the engine starts and only turns over a few 
times and then stops, the cause is likely to be lack of fuel as 
indicated by the fact that it ran on what was injected into the 
cylinders. In priming the float in the carburetor is also depressed 
by means of a button or lever provided for the purpose. This 
floods the carburetor and causes the gasoline to overflow through 
the nozzle into the mixing chamber. The moment any gasoline 
leaks out of the carburetor, the float should be released, since 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 155 

otherwise the cylinders will be flooded. Never prime the car- 
buretor just as the engine is starting, as this will produce an 
over-rich mixture and probably cause & pop back which may ignite 
the gasoline in the carburetor. 

Q. Is water in the gasoline a frequent cause of failure to start? 

A. It may not be a very frequent cause, but the occurrence 
of any water in the gasoline will make it difficult to start the 
motor. Being heavier than gasoline the water sinks to the bot- 
tom of the tank and there may be enough of it to partly fill the 
carburetor. The remedy is to drain the carburetor, taking out 
a half-pint or so. 

Q. What effect does the use of kerosene as fuel have on 
the starting of the motor? 

A. It has no effect, if the matter is properly handled. At 
least five minutes before the engine is to be stopped the kerosene 
should always be shut off and the engine allowed to run on gaso- 
line so that all traces of kerosene will be cleaned out of the 
cylinders and the manifold. If this has not been done, it will 
take considerable cranking to start the engine, and it may also be 
necessary to inject 2 or 3 ounces of fresh oil into each cylinder to 
renew the compression seal since the kerosene condenses in the 
cylinders as soon as they get cold and then runs down past the 
pistons into the crankcase. 

Q. Will an adjustment of the mixture make starting any 
easier? 

A. The actual adjustment of the carburetor itself should 
never be disturbed for starting purposes, as, if this is done, 
either the carburetor will seldom be properly adjusted for efficient 
running or a great deal of time will be spent unnecessarily in 
making adjustments. Moreover the carburetor parts will soon 
wear badly and make efficient adjustment impossible. Most car- 
buretors are provided with a choker which, when closed, causes all 
the air to be drawn past the nozzle, thus increasing the suction 
and giving a rich mixture. This should be closed for starting and 
opened the moment the motor gets under way. Ordinarily the 
running mixture is too lean to make starting easy. 

Q. What are the commoner causes of failure to start 
through ignition trouble? 

165 



166 GASOLINE TRACTORS 

A. Among the causes are the following: a ground op short- 
circuit in the wiring; points of plugs burned too far apart; moisture 
on the distributor of the magneto; failure of the contact points in 
the breaker box of the magneto to separate when the cam strikes 
the hinged lever; impulse starter of magneto stuck or spring 
broken; putting plug cables on wrong plugs when a change has 
been made just before attempting to start; badly sooted plugs; 
spark lever advanced too far; and loose connections, particularly 
where a separate coil is used with the magneto. 

Q. What simple test can be made to determine whether 
the spark is occurring in each cylinder at the proper time? 

A. Take out the plugs, leaving the cables attached to them, 
and lay the plugs on the cylinder head. Then turn the motor 
over slowly and note whether or not the sparks occur at the 
plugs in the proper sequence. Note whether there is a strong 
blast of air from one of the spark plug holes each time the motor 
is turned over; if not, pour an ounce or two of fresh oil into each 
cylinder. The failure to start may be due to lack of compression. 

Q. If, when the spark plugs are thus placed, no spark 
occurs at them, where should the trouble be sought? 

A. Take off the cover of the contact breaker of the magneto; 
have an assistant turn the motor over slowly, and note whether 
the points of the contact breaker separate twice per revolution 
(four-cylinder motor). If they do separate, note whether the 
faces of the contact points are clean and square. If they are 
blackened or pitted, clean and true them up with a very fine file 
or a strip of fine sandpaper, and then so adjust them that they 
come together firmly when the cam is horizontal and do not 
separate more than -fa inch when the cam is vertical. By giving 
the motor a sharp turn beyond a compression point a spark will 
be noted between the points; or the impulse starter may be used 
and the result noted. 

Q. Assuming that a spark takes place between the contact 
points of the magneto, but none occurs at any of the spark plugs, 
where should the trouble be sought? 

A. Open up the distributor of the magneto and wipe it free 
of any moisture or dirt that may have accumulated on it. Turn 
the motor over and note whether the distributor brush revolves as 

166 Digitized by G00gk 



GASOLINE TRACTOBS 167 

it should. Adjust all the spark plug gaps to not more than Vs 
inch; see that the plugs are properly cleaned and that they are 
lying on their sides on the cylinder heads, so that only their 
bodies come in contact with the metal. If they are so placed 
that the central electrodes are touching, the current will pass 
through them without causing a spark, since there are then no 
gaps for it to jump. In case none of these tests produces a 
spark at the plugs, there is more than likely to be some internal 
trouble with the magneto, though this is of comparatively rare 
occurrence. 

Q. When the impulse starter fails to operate, what is likely 
to be the cause of the trouble? 

A. Either the mechanism has become gummed up with oil 
and dirt or the spring has broken. Cleaning out the impulse starter 
with gasoline and re-oiling will remove the former cause. 

Q. When the engine fails to start after having been primed 
once or twice and cranked several times, in what order should 
the cause of the trouble be sought? 

A. This will depend largely upon weather conditions. In 
very cold weather it is quite likely that nothing but the low tem- 
perature is the cause of difficulty in starting. Results will usually 
follow continued cranking, as this warms the engine up somewhat 
and makes it turn over easier, with the result that the first weak 
explosions may cause it to take up its cycle. In warm weather, 
if a start does not follow several attempts at cranking, test the 
ignition first and then the fuel supply, applying the different tests 
already outlined and in about the order given. 

Q. Are there any other points in the ignition system that 
are likely to be responsible for failure to start? 

A. If, when turning over, the motor produces a spark at the 
contact breaker but none at the plugs, investigate the magneto 
switch. It may have become broken or its connections may be 
faulty. See that it is in the right position, since many tractor 
motors can only be stopped by short-circuiting the magneto by means 
of the switch. In case the switch is in the S TOP position, no spark 
will occur at the plugs. On some tractors the spark-advance lever 
takes the place of the switch; by fully retarding it the magneto is 
short-circuited, and the motor cannot be started. 

167 Digitized by G00gle 



158 GASOLINE TRACTORS 

Q. Do the magnets of the magneto lose so much of their 
strength that no current is produced? 

A. In time, the heat and vibration are liable to weaken the 
magneto, but this is far from being a common source of trouble. 
If, after making the tests mentioned, no spark is produced, take 
off the distributor plate of the magneto and rest a screwdriver 
blade on the gear casing so that its end comes within | inch of 
the collector ring. Turn the motor over, and note whether a 
spark jumps this gap. A J-inch spark at this point will indicate 
that there is no falling off in the power of the magneto. If a 
spark cannot be produced in this way, there is something wrong 
with the magneto itself, and it should be sent to the manufac- 
turer for repairs. Ordinarily remagnetization is only necessary if 
the magneto has been taken apart and the magnets allowed to 
stand without a "keeper," or piece of soft iron across their ends, 
or if they have been removed from the magneto and reassembled 
in the wrong way. 

Q. When the contact points have become so badly pitted 
and burned away that they cannot be properly adjusted after 
cleaning and trueing up, what should be done? 

A. One or both of the contacts should be replaced and 
adjusted properly. The magneto manufacturer usually supplies a 
special wrench for this purpose, one end of it serving as a gage 
for the proper gap between them. The lock nut of the movable 
point should always be screwed down firmly after the adjustment 
has been made or it will back off owing to the vibration. 

Q. Are there any connections on the magneto which are 
likely to become short-circuited or grounded? 

A. When the wire is brought out through the side of the 
magneto, the insulation may become so worn that the metal 
touches the side of the opening, causing a short-circuit. In the 
inductor types of magneto, such as the Remy and K-W, this is 
most likely to occur at the grounding screw where the wire is 
fastened to the side of the magneto. In shuttle-wound types, 
such as the Eisemann, Kingston, and Bosch, the break may be 
at the point where the wire is fastened to the armature or where 
it is fastened to the collector ring. 

Q. Can the contact breaker become short-circuited? 



168 



Digitized by VjOOQIC? 



GASOLINE TRACTORS 159 

A. Metallic dust or filings will be liable to cause this; the 
remedy is to clean out the inside of the box with gasoline. When- 
ever an adjustment is made, the contact points must always be 
redressed so as to come together squarely. For this purpose use 
only the small file supplied by the manufacturer, and take off just 
as little of the platinum as possible, since it is worth consider- 
ably more than gold. 

Q. How can the contact-breaker box be tested for a short- 
circuit? 

A. Remove it from the magneto, place a piece of paper 
between the points, and then hold the box within | inch of the 
shaft while the magneto is turned over with the other hand. No 
spark should occur; if it does, it indicates that the insulation of 
the adjustable contact point is poor and should be replaced. 
The test should then be repeated with the paper removed so that 
the points are in contact; a spark should then occur when the 
armature is turned over, the breaker box being held within f 
inch or less. 

Q. Does oil getting on the parts injure the magneto in any 
way? 

A. If allowed to get between the contact points in the 
breaker box, it will insulate them. On the shuttle-wound types of 
magneto there is a collector ring and brush, and allowing any oil 
to get on them will prevent the operation of the magneto alto- 
gether. Oil usually carries more or less dirt with it, and if 
allowed to get on the distributor, it is liable to cause leakage of the 
high-tension current, so that no spark occurs at the plugs. 

Q. How often should the contact points of the magneto 
need attention? 

A. This will depend more or less on the particular type of 
magneto and the engine, but they should be inspected at least 
once every thirty days while the tractor is in service steadily and 
trued up with the sandpaper or special file whenever the slightest 
irregularity of their surfaces is evident. Taking off a little at fre- 
quent intervals will keep the points in much better condition and 
will save the costly platinum, since once the points start to pit 
this process proceeds very rapidly. Emery should never be used 
on the points. 



Digitized by VjOOQ IC 



IdO GASOLINE TRACTORS 

Q. Is excess oil in the motor ever a cause of failure to start? 

A. When there is so much oil in the motor that considerable 
of it finds its way into the combustion chambers, it will collect on 
the spark plug points and insulate them, if unburned, or short- 
circuit them, if carbonized. The fact that the motor apparently 
ran satisfactorily just before being shut down the last time is not 
conclusive evidence that the spark plugs are in good condition. 
The magneto generates a high voltage when running at full speed, 
and the motor will often continue to operate in spite of poor con* 
ditions whereas it cannot be started again, once it has become 
cold, without first remedying the faults. 

Q. What is the commonest cause of failure to start a motor 
equipped with low-tension ignition? 

A. Dirty plugs, or ignitors, are probably the most frequent 
cause. As in the case of the high-tension spark plugs just men- 
tioned, the engine may continue to run with the plugs in poor 
condition, but once it has been shut down and allowed to become 
cold, the magneto will not produce a spark at the dirty plugs at 
the low speed at which the engine is cranked. Whenever an 
engine with this type of ignition is difficult to start, the first 
thing to do is to examine the plugs. Give them a thorough clean- 
ing with gasoline and a wire brush, taking out the moving contact 
to remove any soot that has been forced into the bearing. These 
plugs may be tested by laying on the cylinder head, contacts up, 
and snapping the contact with a small piece of wood while an 
assistant turns the motor over so that the magneto is generating. 

Q. What other attention do these plugs require? 

A. The contact points burn away rapidly and need frequent 
dressing up to keep their contact faces from becoming pitted. 
They should be trued up in the same manner as directed for the 
magneto breaker-box contact points, and while the material is not 
so expensive, no more than necessary should be taken off. The 
operation should be repeated at frequent intervals to keep the 
plugs in good condition. 

Q. How may the low-tension magneto be tested to find 
out whether it is generating or not? 

A. Place a screwdriver blade against the single terminal of 
the magneto and hold the end against some metal part of the 

Digitized by VjOOQ IC 



GASOLINE TRACTORS 161 

motor while the motor is cranked. Move the tip of the screw- 
driver over the metal while maintaining contact with the terminal . 
at the other end and sparks will be noted at the tip. A similar 
test may be made by disconnecting the cable leading from the 
coil. Rub the metal terminal of this cable over different adjacent 
parts of the motor so that contact is made and broken while the 
engine is being cranked, and much larger sparks will be noted. 

Q. If, after making tests successfully, no spark is obtain- 
able at the ignitor plug itself, what is the cause of the trouble? 

A. The plug is likely to be at fault. Oil that has been used 
for any time carries in solution a considerable percentage of 
carbon in a finely divided state. When hot, this oil is thin and 
is forced into the insulation of the plug, short-circuiting it, 
though apparently there is nothing wrong with it. The only 
remedy is to renew the insulation of the plug. 

Q. Though a test of the ignitors shows them to be in good 
working condition, the motor still fails to start and examination 
shows every other part to be working properly, so that the fault 
is evidently with the ignition, what is the cause? 

A. Either some part of the ignitor tripping mechanism has 
failed, so that the contacts do not separate, or the timing has 
become deranged, so that the separation takes place at the wrong 
moment. In the latter case the spark is occurring in the cylinder, 
but it is taking place either too soon or too late to fire the charge. 
Check up the timing of the ignitor mechanism in accordance with 
the maker's instruction book. 

Q. How can the dry cells ordinarily used for starting with 
low-tension ignition be tested? 

A. A pocket ammeter, or so-called battery tester, should be 
used for this purpose. Hold the tips on the cells only long enough 
to allow the instrument needle to come to rest, since the ammeter 
represents a dead short-circuit on the battery and will run it down 
very quickly. If the reading of the ammeter shows less than 10 
amperes, the batteries are of no further use for starting purposes 
and should be renewed. Any other method of testing will only 
show whether the battery is actually dead or not, and dry cells 
may make a fairly large spark through the coil but will give a 
reading of only 2 to 3 amperes on the instrument and will fail to 

Digitized by VjOOQ IC 



162 GASOLINE TRACTORS 

ignite the charge in the cylinder. Batteries when this low give 
out very quickly. If the switch has been left on the battery side 
inadvertently, give the cells ten to fifteen minutes to recuperate 
and then test again. 

Q. What is likely to go wrong with the wiring of a low- 
tension system? 

A. About the only thing that can happen to this wiring is a 
loose connection at the magneto, at the ground on the motor, at 
the ignitor connection, or at the switch. The switch itself may 
become short-circuited and thus prevent any current from reach- 
ing the plugs. 

Q. Does the tripping mechanism of a low-tension system 
require frequent attention? 

A. The trip-rod mechanism should be inspected from time 
to time to see that it is working normally, as the vibration is likely 
to knock it out of adjustment. The spiings should be replaced 
whenever they show any signs of weakening. 

RUNNINQ TROUBLES 

Q. What causes the engine to emit smoke? 

A. Among the causes are the following: an over-rich mixture 
caused by faulty adjustment of the carburetor; and flooding of the 
carburetor due to a leaking metal float or a water-logged cork 
float. In either of these cases the smoke will be black. Oil get- 
ting into the combustion chambers in excess, caused by feeding 
too much oil or by broken or stuck piston rings, will produce a 
blue smoke. Feeding an excessive amount of water when burning 
kerosene or running the engine too cold will produce a white or 
gray smoke, indicating that the kerosene is not being entirely 
consumed. 

Q. What is the cause of back firing through the carburetor? 

A. A slow-burning fuel mixture is being fed, that is, one 
either too lean or too rich, usually the former, so that there is 
still flame in the cylinder when the valve opens. At times this 
will occur to such an extent that the flame issues from the exhaust 
pipe at the end of the muffler. This is an indication that the 
mixture is too rich, since it is still burning after being exhausted 
from the cylinder. One of the valves may not be closing properly; 

172 Digitized by G00gle . 



GASOLINE TRACTORS 106 

it may be held off its seat slightly by an accumulation of carbon, 
op its stem may have become bent, so that the spring cannot 
close it. When the ignition has been dismantled, reassembling 
the cables on the wrong plugs so as to alter the firing order will 
cause a back fire, but in this case the engine cannot be started. 
An air trap in the fuel line or partial clogging of the latter will 
also cause this at times. 

Q. What are the commoner causes of missing? 

A. The most frequent cause is a defective spark plug. 
Owing to the heat and the vibration the porcelain of a plug will 
break, but the cracks will be so small that they are invisible. 
The pressure forces carbon-laden oil into these cracks and the 
plug becomes short-circuited, though apparently in good order. 
Test by short-circuiting the plugs in turn with a wooden-handled 
screwdriver. When short-circuiting a plug causes no perceptible 
difference in the running of the engine, replace it. Pitted and 
badly worn contact points in the magneto breaker box will also 
cause irregular running. (See the directions given under Failure 
to Start.) Missing may also be caused by the fuel mixture being 
too rich or too lean, partial stoppage of the fuel line, water in the 
gasoline, defective insulation or loose connections, carbon dust on 
the distributor plate of the magneto, or a sticking valve. 

Q. In what other ways may spark plugs fail besides the 
porcelain cracking? 

A. Very frequently the electrodes burn too far apart, so that 
the current is unable to jump the gap, or if it does, the spark is 
weak and irregular. Plugs become foul through an accumulation 
of soot in them,- and to clean a badly sooted plug out thoroughly, 
it may be necessary to take it apart. The insulation of a mica 
plug will fail in time through the hot oil and carbon being driven 
into it under pressure, and the only remedy is to replace the 
insulator. Leakage around the gasket sometimes occurs, and 
when it is not sufficient to cause a hissing noise, it will be indi- 
cated by the porcelain of the plug becoming very dirty. Squirt a 
little oil on the porcelain when the engine is running and bubbles 
will form at the gasket if the plug is leaking. Cheap plugs are 
made with iron electrodes, and the latter burn away so fast that 
it may be necessary to adjust the gap once a day. 



173 



164 GASOLINE TRACTORS 

Q. What is the cause of preignition? 

A. Usually an accumulation of carbon in the combustion 
chamber. This carbon deposit often takes the form of small 
cones which become incandescent when the engine is running 
under full load so that the fresh mixture is ignited the moment 
it enters the cylinder. When running on kerosene, the piston 
head may become so hot as to produce the same result. In 
either case, preignition will be evidenced by a heavy pounding 
and the engine should be stopped at once as this imposes a very 
heavy stress on all the moving parts. Increasing the amount of 
water fed with the fuel will remedy it when it is due to over- 
heated pistons and the use of kerosene. Otherwise, the engine 
will have to be cleaned out to remove the carbon. 

Q. How can the accumulation of carbon be prevented? 

A. By using only the grade of oil recommended by the 
manufacturer of the tractor; cleaning it out and putting in a 
fresh supply as often as directed; keeping the piston rings in good 
condition, so that an excessive amount of oil cannot find its way 
into the combustion chambers; and keeping the carburetor 
properly adjusted, so that too rich a mixture is not used. Feed 
the proper amount of water when burning kerosene. In spite of 
these precautions, more or less carbon will always accumulate in 
the cylinders. This amount can be kept down to a minimum by 
pouring a few ounces of kerosene into each cylinder at the end of 
a day's run when the engine is still very hot and leaving this in 
the cylinders over night. Before starting up in the morning, the 
compression seal should be renewed by putting a few ounces of 
fresh oil into each cylinder. 

Q. When the engine fires regularly but the explosions are 
so weak that very little power is produced, what is the cause of the 
trouble? 

A. Some of the commoner causes are as follows: spark plug 
points burned too far apart; excessive clearance at the valve stem 
tappets or rocker arms, so that only a fraction of the fuel required 
is being admitted; valves in need of grinding; poor compression 
caused by oil not being renewed at sufficiently short intervals; 
broken or stuck piston rings; leaks around spark plugs; use of a 
fuel mixture that is too lean or too rich, so that slow burning 



Digitized by VjOOQ IC 



GASOLINE TRACTORS 165 

results instead of an explosion; a weakened or broken valve 
spring; clogging of the passages of the muffler with carbon; or 
any obstruction in the exhaust piping. 

Q. What causes the engine to run regularly for a time 
and then to misfire badly? 

A. This may be caused by switching to kerosene before the 
engine has run long enough on gasoline to become thoroughly 
warmed up; a valve with a bent stem that operates properly at 
times and then sticks during a few revolutions; air leaks around 
the valve stems or in the intake manifold; dirt in the carburetor, 
so that the nozzle is partly clogged at times and free at others; 
defective insulation or a loose connection which interrupts the 
circuit from time to time owing to the vibration of the engine, 
causing it to change position; water in the gasoline; carbon on the 
distributor plate of the magneto; or faulty spark plugs which will 
permit the engine to run regularly when idling but which will fail 
the moment the load is applied. A spark plug with fine cracks in 
the porcelain will fail under load owing to the greatly increased 
pressure in the cylinder, but will often spark regularly when the 
engine is running without load. A loose connection or weak spot 
in the insulation is the most puzzling of these causes since it is 
often the most difficult to find. 

Q. What causes the engine to stop suddenly? 

A. This is generally due to a failure of the ignition, owing 
to a break in the circuit caused by a connection dropping off, the 
switch suddenly opening under the vibration, or some part of the 
wiring becoming short-circuited. Clogging of the fuel line or of 
the carburetor nozzle or an empty tank will also result in the 
engine stopping. Where the stoppage is due to failure of the fuel 
supply from any cause, the engine will not usually come to as 
sudden a stop as when the ignition fails. The contacts in the 
breaker box of the magneto may have stuck together. If the 
cooling or the lubricating system fails, it will also take more time 
to bring the engine to a stop and there will be noises that give 
ample evidence of the cause of the trouble. The engine should be 
shut off the moment these noises occur for otherwise it will be 
forcibly stopped by the binding of the pistons, thus putting the 
engine out of commission. 

175 Digitized. by G00gle 



166 GASOLINE TRACTORS 

ENQINE NOISES 

Q. How are the different engine noises that signify trouble 
in the operation of the motor characterized? 

A. Experienced motor mechanics give a different term to 
each one of several distinct classes of noise indicating faulty 
operation, such as knock, hammer, pound, and slap, and to the 
ear that is familiar with them each can be distinguished. 

Q. What do these different noises signify to' the experi- 
enced ear? 

A. A knock is the first indication of looseness in a bearing, 
usually a connecting-rod big end, and the sound is generally that 
of a sharp metallic blow. When it is allowed to develop or when 
looseness in the crankshaft bearings develops, the sound becomes 
louder but not so sharp and is more aptly described as hammer- 
ing, owing to its similarity to the blow of a sledge. Pounding is 
caused by preignition and by overheating and is so violent as to 
rack the whole motor very badly. Slap is the result of worn 
pistons, the skirts or lower ends of which are banged against 
the cylinder walls every time the motor fires. The noise pro- 
duced is very similar to that of a knock and is often mistaken 
for the latter, though an experienced mechanic will seldom go 
wrong on this. In addition to the noises mentioned, there is 
another that is readily distinguished by the experienced ear, and 
that is the clatter caused by a loose valve motion, indicating 
that an excessive amount of clearance has been allowed to develop 
between the valve tappets and stems or in the rocker arms. To 
the inexperienced ear all strange noises will be knocks and it may 
seem to be drawing too fine distinctions to differentiate between 
knocking, hammering, and pounding, but familiarity with a motor 
will enable the operator not only to make these distinctions but 
to know as well what causes the different noises. 

Q. Which of these noises calls for immediate attention on 
the part of the operator to prevent damage to the motor? 

A. A very good rule to follow is to shut the motor down 
the moment any of these ijoises is heard and correct the trouble, 
but those that call for immediate attention to prevent serious 
damage are hammering and pounding. The first indicates a very 
loose bearing which may result in a broken crankshaft if allowed 



.Google 



Digitized by VjOOQI 



GASOLINE TRACTORS 167 

to run a moment longer than necessary, while pounding not only 
imposes exceedingly heavy stresses on every part of the motor 
but may also be the first sign of failure of either the cooling or 
the lubricating system. The cause may be nothing more serious 
than lack of sufficient water when burning kerosene or the fact 
that the spark lever may be advanced too far. 

QOVERNOR 

Q. What causes the engine to race when the load is thrown 
off? 

A. The governor needs adjustment, or the connection between 
it and the throttle has parted. 

Q. What attention does the governor ordinarily need? 

A. This depends largely upon the type of governor. Some 
are housed in and the lubrication provided for by filling the 
housing with oil; such a governor needs very little attention, 
except to adjust it when it permits the engine to idle too fast. 
An adjusting screw is provided for this purpose. With the engine 
running, turn the screw gradually until the engine slows down 
to a point where it idles satisfactorily. The governor spring 
weakens in time, and the adjustment is provided to permit of 
increasing the tension. Apart from this, the only regular atten- 
tion required by those types which are not automatically lubri- 
cated is to oil the bearings at regular intervals and see that the 
connecting linkage is in good order. 

CLUTCH AND TRANSMISSION 

Q. What provision is made for taking up wear in the clutch? 

A. The friction surface, which is usually asbestos on a wire 
foundation, should be replaced when worn sufficiently to require 
it. After considerable service the spring pressure may let up 
sufficiently to cause unsatisfactory operation of the clutch. An 
adjustment is provided for increasing the tension of the spring, 
and this should be tightened just enough to make the clutch hold 
under load; but it is not good practice to attempt to make up for 
a badly worn friction facing by increasing the tension of the 
spring. Replace the facing first. This, of course, does not apply 
to the type employing metal to metal contact surfaces. Apart 

Digitized by VjOOQ IC 



168 GASOLINE TRACTORS 

from this, the chief attention required is lubrication, which should 
be carried out in accordance with the manufacturer's instructions, 
some clutch mechanisms calling for oil as much as two or three 
times a day. 

Q. Is it good practice to let the machine stand with the 
clutch out of engagement? 

A. No; as it only weakens the clutch spring and shortens 
its life. Whenever the machine is to stand more than a few 
moments, the gears should be shifted to neutral and the clutch 
allowed to engage. It is particularly bad practice to let the 
machine stand over night with the clutch out of engagement. 

Q. Are a worn friction facing and a weak spring the only 
causes of a slipping clutch? 

A. Allowing oil or grease to fall on the friction faces of the 
clutch will cause it to slip badly. 

Q. What attention does the transmission require? 

A. Maintain the oil level as indicated in the manufacturer's 
instructions and use only the oil called for by the latter. Drain 
as often as instructed, and' wash out with gasoline or kerosene 
before refilling. This is usually two to three times a season, 
though some types may require it oftener. When the case has 
been cleaned out, inspect the gear teeth carefully for breaks, 
and see that any chips or foreign matter are removed. By 
filtering the old oil through several thicknesses of cloth, it may 
be used for other farm machines which do not require the same 
high degree of lubrication as the tractor. 

Q. Does the differential require any special form of attention? 

A. The differential is frequently combined with the trans- 
mission, so that it is lubricated by the same supply of oil. Where 
it is separate from the transmission, the attention required is the 
same as that just mentioned for the transmission. 

HOUSING TRACTOR 

Q. Does it pay to build a special shelter for a tractor? 

A. It will undoubtedly be found a good investment, since 
the cost of a building large enough to shelter the tractor and 
provide a working bench beside it will usually be less than the 
^dded depreciation incurred by leaving it exposed to the weather. 



.Google 



Digitized by VjOOQI 



GASOLINE TRACTORS 169 

Q. When the tractor is put up for the season, what atten- 
tion should be given it? 

A. Before putting the machine away for the winter, the valves 
should be ground, the bearings adjusted, the valve mechanism 
and the magneto overhauled, the oil drained from the crankcase 
and the transmission, and the latter washed out and provided 
with a fresh supply of oil. Wash the cylinders and pistons by 
putting a pint or more of gasoline in each cylinder and running 
the motor for half a minute. Then put a pint of fresh oil in 
each cylinder and turn the motor over by hand a few times to 
spread it over the surfaces; otherwise, the cylinders and pistons 
may rust. Coat all exposed parts with grease and cover the 
machine with a tarpaulin or old canvas. Make a list of all 
replacement parts necessary and order them at the time the 
machine is put away in order that they may be installed during 
the winter. 



Digitized by VjOOQ IC 



Digitized by VJ.OOQlC 



COMMERCIAL VEHICLES 



INTRODUCTION 

Development of Field. While the development of the com- 
mercial car was slow at first owing to the numerous shortcomings 
of early types, it has advanced with wonderful rapidity during the 
past few years and bids fair to supersede, in a comparatively short 
time, the use of the horse-drawn vehicle for business purposes, not 
only in the large cities but also on the farm. As in the case of the 
pleasure car, Europe led in the development of the automobile for 
transportation purposes, chiefly with military necessities in view, as 
without power-driven vehicles it would be impossible to move the 
enormous food and ammunition supplies required by an army of 
present-day proportions. However, American manufacturers have 
advanced so rapidly in the production of commercial cars during the 
past few years that in 1916 the registration of New York City alone 
showed a greater number of these vehicles than were reported by the 
census of 1915 for the whole German Empire and more than half the 
number reported in service in Great Britain during the same period. 

Scope of the "Commercial Vehicle". It is important to know 
the reasons for the revolution which is now in active progress, as well 
as to become familiar with the prevailing practices in America and 
abroad in the construction, operation, and maintenance of that large 
and varied class of automobiles employed exclusively for business 
purposes. Regardless of type, class, or method of propulsion, these 
are commonly referred to as "commercial vehicles". This classifi- 
cation embraces not only motor delivery wagons and trucks for the 
transportation of merchandise, but also taxicabs, omnibuses, sight- 
seeing vehicles, motor road trains, farm tractors, emergency repair 
or tower wagons for street-railway service, and also vehicles for 
special municipal service — ambulances, patrol wagons, fire engines, 
street-sprinkling and garbage-removal wagons, and the like. In fact, 
it may be said that any automobile not devoted to pleasure is a com- 
mercial vehicle, and, as was to be expected, the first types of these 

181 



2 COMMERCIAL VEHICLES 

vehicles were merely pleasure cars transformed to suit the needs of 
the occasion. To a certain extent, this still continues to be the case. 

Standard Design. Whether it be electric-, steam-, or gasoline- 
driven, the general design of the motive power, as well as that of its 
transmission to the driving wheels, is practically the same in the 
commercial vehicle as it is in the pleasure car, except that the chain 
drive has now almost disappeared on the latter, and all the com- 
ponent parts — bearings, frames, axles, steering gear, and compen- 
sating mechanism — are the same. In other words, the chassis in 
both cases is composed of similar members. For the sake of brevity 
in the present treatise, it is assumed at the outset that the reader 
has become familiar with motor-car engineering so far as it relates to 
pleasure-car construction; that he understands, from previous study 
and the actual handling of machines, the theory of the operation of 
the internal-combustion engine; that he is conversant with the dis- 
tinguishing characteristics of the several types of engines as well as 
with their advantages and limitations; and that he is acquainted with 
the types of transmission systems ordinarily employed on pleasure 
cars — in brief, that he understands any reference to component parts, 
to their functions, and to their relation to one another, without the 
necessity of explanation. 

In common with the pleasure car, the commercial vehicle is 
capable of traveling at various speeds wherever road conditions will 
permit it to go. Both comprise in a single entity a wheeled vehicle 
suitable for transportation purposes, fitted with an independent, self- 
contained power plant, and both present the same engineering prob- 
lems so far as they relate to the construction of the motor, its control, 
and the transmission of its power to the road wheels, the design of the 
running gear, and the control of the vehicle itself. Divergence in 
practice is encountered with the consideration of the purposes for 
which each vehicle is designed. The pleasure car is not intended to 
be a very efficient vehicle. Its carrying capacity bears a compara- 
tively insignificant ratio to its total weight, and, usually, the car is not 
designed to work under the same severe and continued conditions 
of service that are the first requirements of the commercial vehicle 
It must be capable of high speed with its maximum load of passen- 
gers and must combine reliability with endurance to an extent 
sufficient to meet the demands of its owner when on pleasure bent. 

Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 3 

Classification. In order to make the subject as clear as possible 
and to facilitate reference on the part of the student, industrial motor 
vehicles as a whole have been classified, first, by their motive power; 
and second, by the uses for which they are intended. Thus there 
are, today, in the order of their relative importance: 



Motive Power 



Types of Vehicles 



Electric vehicles -, 

Gasoline-driven vehicles 
Gas-electric vehicles 
Steam vehicles 

Industrial electric trucks 

Delivery wagons 

Trucks, vans, and similar freight carriers 

Passenger vehicles — stages, busses, taxicabs, sight-seeing 
cars, etc. 

Municipal vehicles — patrol wagons, ambulances, fire appa- 
ratus, garbage-removal wagons, street sprinklers, etc. 

Special types — railway tower wagons, emergency repair 
wagons, farm tractors, road trains, etc. 

This classification has been made advisedly, for, though kerosene 
and alcohol are being experimented with as fuels for the internal- 
combustion engine and particularly for commercial purposes, by 
far the greater majority of types marketed at present are driven 
by gasoline fuel. 

Each of the foregoing principal divisions is susceptible of further 
subdivision, but this is neither necessary nor desirable. Commer- 
cial motor vehicles are now built for almost every conceivable 
purpose involving freight hauling or the transportation of pas- 
sengers and include many special uses, such as hauling huge reels of 
telephone cable and drawing the cable through the underground 
conduits, transporting and hoisting safes and pianos, delivering coal 
with special dumping wagons, and the like. They differ only in the 
special equipment with which they are provided for the service in 
view, and, as their construction otherwise is the same, it would only 
lead to confusion to attempt to consider them separately. 

ELECTRIC VEHICLES 

Range of Use. Owing to the general recognition of its simplicity 
and economy, which has been brought about by a co-operative 
propaganda fostered by the electric lighting and power companies, 



183 



4 COMMERCIAL VEHICLES 

the growth *of the use of the electric commercial vehicles during the 
past few years has been little short of phenomenal. One New York 
firm alone uses nearly 350 electric delivery wagons, several have 
nearly 100, while no fewer than forty-five have "fleets" of 10 cars or 
more. All told, there are several thousand electric vehicles in New 
York City and more than 100 garages and charging stations, while 
the demand for current has been so^ great that the minimum for 
charging batteries has recently been reduced to $10 per month. 
Current is supplied at a preferred rate under special contract, which 
calls for the charging of the batteries during those hours of the night 
when the load on the central stations is lowest. 

Advantages of the Electric Type. Simplicity. One of the chief 
advantages of the electric vehicle, when judged from the purely com- 
mercial point of view, is its great simplicity, which, to a very large 
extent, solves the labor question that has proved such a deterrent to 
the adoption of the gasoline vehicle for commercial service. As the 
duties of the driver of an electric vehicle do not extend beyond its 
actual starting, stopping, and guidance while under way, anyone 
who has been accostumed to the use of horses can master its operation 
in the course of a few hours. This also appears to be equally true 
of men who have never driven any type of vehicle previous to their 
taking the wheel or steering tiller of an electric. Apart from the actual 
mechanical control of the vehicle, the driver's only other care is to 
keep informed as to the state of charge of the battery by watching 
the voltmeter, in order to prevent running the car with the batteries 
exhausted, as this is very detrimental to their continued usefulness. 
However, as the batteries of most commercial vehicles are charged 
every twenty-four hours and the car run is planned to lie within its 
traveling radius on a single charge, with a factor of safety allowed in 
addition, this is not a very onerous duty. The further requirement 
of noting the current consumption on starting and running, as indi- 
cated by the ammeter, in order that any defect in the operation of the 
running gear of the car may be detected and remedied, is also a very 
simple one, so that an unskilled driver is available at a correspond- 
ingly lower charge for labor cost in the operation of the vehicle. The 
adoption of the ampere-hour meter showing the actual consumption 
of battery energy has simplified the task of the driver still 
further. . 

184 ' W ^ Digitized by G00gle 



COMMERCIAL VEHICLES 5 

Efficiency and Long Life. Broadly speaking, short runs with 
many stops are the province of the electric, so that probably 80 
per cent of all average city deliveries come within its economic field. 
Its labor cost is much lower than that of the gasoline car, since an 
unskilled hand can operate it efficiently, while one man at the garage 
can take care of nearly twice as many electrics as of gasoline cars. 
The electric is easier on tires, owing to its reduced speed, insurance 
rates are lower, and its depreciation can be figured on a much more 
favorable basis, as it has been shown to have an average effective 
life of ten years. The fact that all its moving parts revolve has a 
most important influence on its low maintenance cost and reliability, 
many electric trucks showing an average of 297 days in service of 
the 300 working days in a year. 

Power Efficiency. The amount of power available on a single 
charge of the batteries without unduly increasing the weight is so 
limited that in the design of the electric great care must be taken 
to eliminate friction and other sources of power loss at every possible 
point. This is further necessitated by the gradually decreasing 
efficiency of the batteries with age. Starting with 80 per cent 
when new, the efficiency may drop rapidly to 50 per cent or below 
unless the batteries are properly maintained, which is likewise true 
of the transmission efficiency of the running gear of the vehicle; so 
that while unskilled labor may be employed for the operation of the 
vehicles this is not the case where their maintenance is concerned. 
Power losses due to the tires are also an important factor, and as 
the pneumatic tire can very seldom be considered for commercial 
service, the same degree of efficiency is not obtainable from the busi- 
ness electric wagon as from the pleasure type employing the same 
motive power. Road conditions must also be considered — despite the 
fact that electrics are employed almost exclusively for city or near-by 
suburban service — as mud, snow, and ice in winter, and poor pave- 
ments at any time cause an increase in the current consumption. 

ELECTRIC DELIVERY WAGON 

General Specifications. Whether considered from the point of 
view of design and construction or from that of operation, the 
electric delivery wagon is, without doubt, the simplest vehicle in 
the commercial field. As already mentioned, its operation may be 



Digitized by VjOOQ IC 



6 COMMERCIAL VEHICLES 

mastered in a comparatively short time, either by the ex-horsedriver 
or by a person who has never had any experience in the control of a 
vehicle, so that the labor cost — always an item of importance in this 
field — may be materially reduced without fear of the equipment 
suffering in consequence. It is usually customary with manufac- 
turers of these vehicles to adopt a standard form of design, which is 
employed throughout in every size listed by the same maker, the only 
differences being those of dimension, load capacity of the vehicle, 
and capacity of the battery to take care of the increased weight. 

Package delivery wagons and express wagons of the electric 
type have a useful load capacity ranging from 1000 to 2000 pounds, 
though a very few of less than 1000 pounds' capacity were employed 
at first. The 40-mile run is standard and is based on an average 
speed of 10 to 20 miles an hour, including stops, as the necessity 
for frequently stopping and re-starting the car in delivery service 
has an important bearing on the mileage of which the car is capable 
on a single charge. The latter is naturally figured on the maximum 
efficiency of the car as a whole, so that in practice this is seldom 
fully realized, owing to the deterioration of the batteries in service. 

Design. The electric has progressed through the stages repre- 
sented by the angle-iron frame, the armored wood frame, and the modi- 
fications of the two as employed on gasoline cars to the now generally 
current type of pressed-steel frame. This frame has the advantage 
of being extremely strong for its weight. It is composed of side and 
transverse members produced in hydraulic presses- directly from 
steel plates of about A -inch thickness, these members being riveted 
together and further reinforced by gussets at the corners. On 
account of the height of the vehicle, the frames are made perfectly 
rectangular and without either a drop or narrowing forward. 

The types of suspension employed also show the same variations 
as are to be found in the gasoline-driven cars, some of the smaller 
electrics having the full elliptic springs ordinarily employed on 
wagons, while intermediate and heavy vehicles have either straight 
semi-elliptic springs front and rear or a half-platform type of sus- 
pension in the rear. A study of the Baker and General * Vehicle 
types of delivery wagons and trucks will show how closely they 
approach, as a whole, to what is considered general practice in the 
automobile field. 



Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 7 

Because of the heavy loads carried and of the fact that solid 
tires are used, the entire running gear has to be planned on a very 
liberal scale. This is likewise true of the springs. While it is desir- 
able that the latter afford as much protection to the mechanism as 
possible, sufficient stability to carry the load is of more importance 
than flexibility, as the comparatively slow speeds do not occasion 
the violent shocks met with in the pleasure car. 

MOTIVE POWER 

Type of Motor. As already mentioned, the motive power of 
the majority of smaller electric vehicles consists of a single motor, 
and, in several makes, such as the Waverley, G.V., G.M.C., and 
Detroit, this practice extends to heavy units, with a corresponding 
increase in the efficiency of the vehicle as a whole. In order to keep 
down theweight as well as the space occupied, these motors are very 
small for their power output, and consequently have to be wound for 
high rotative speeds. They are usually of the series type of the 
General Electric or the Westinghouse make and are designed to 
carry heavy overloads for short periods, to enable the car to pull out 
of a bad place, to start with full load on a heavy grade, or to meet 
similar emergencies, the motor, under such conditions, delivering 
an amount of power greatly in excess of its normal rating. 

Motor Suspension with Chain Drive. Since the use of spur-gear 
drives has decreased, the motor is usually suspended from the frame 
by means of transverse members riveted to the side rails and is 
placed near, or slightly forward of, the center of the chassis, in 
order to give the best distribution of weight. This is an advantage 
not obtainable when the motors are hung from the rear axle or too 
close to it. In view of the high speed at which the motors run — 1800 
to 2000 r.p.m. or more — a reduction in two stages is necessary to 
avoid the employment of excessively large sprockets. The first step 
is from the motor to a countershaft by means of a single silent chain 
of the Morse or the Renold type, the motor being suspended in such a 
manner that it may be moved a short distance one way or the other 
to permit the adjusting of this chain to the proper tension, Fig. 1. 
The large sprocket on the countershaft, which serves to cut down the 
speed in the proportion of about 1 to 5, also embodies a differential, 
or compensating, gear of the usual bevel or spur type, thus making 

■' 187 



8 COMMERCIAL VEHICLES 

it possible to employ a solid one-piece axle instead of weakening 
the latter by inserting the balance gear in it. This is an important 
feature, as the rear axle must bear 60 to 70 per cent of the total weight 
of both the car and the load. Erom the countershaft, chains are run 
to each of the driving wheels. The relative positions of the counter- 
shaft and the rear axle are maintained by heavy adjustable radius 
rods, attached forward to the outer ends of the countershaft and, at 
the rear, to the axle. These rods take the stress of the drive off the 



Fig. 1. Motor Suspension and Silent-Chain Drive on Baker Trucks 

springs and counteract the tendency of the chains to draw the rear 
axle toward the countershaft, under the pull of the motor. 

Motor Suspension with Shaft Drive. On light delivery wagons of 
the shaft-driven type, three methods of motor suspension may be 
noted. In the first method, the motor is place^ just forward of the 
rear axle, its housing being practically integral .with that of the axle. 
Either a worm drive permitting of a single-speed reduction or a two- 
speed gear through spur gears is employed. As the motor moves with 
the axle and their relations are fixed, flexible joints are not required. 
A modification of the first method consists in placing the motor under 
the car at about the center and mounting it on a flexible suspension 
so that it can move under stress without disturbing it& alignment; 
while the third method provides for taking such stresses on universal 
and slip joints interposed between the motor and the rear axle. 



188 



Digitized by VjOOQIC 



COMMERCIAL VEHICLES 



Digitized by Cj'OOQ IC 



10 COMMERCIAL VEHICLES 

The relative locations of the various essentials of a delivery 
wagon of the single-motor side-chain-drive type are clearly shown 
in Fig. 2 that illustrates a G.V. chassis of 4000 pounds' capacity, this 
being the same except for the difference in size. 

Worm-Gear Transmission. While the power is transmitted 
through a combination-chain drive, i.e., silent chain for the first 
reduction and roller chains for the final drive, on the majority of 
delivery wagons, the practice of utilizing the worm drive, which has 
recently been adopted on the pleasure cars, has also been taken up 
in this field on the light vehicles. An example of this is represented by 



Fig. 3. Rear Axle of Commercial Electric Delivery Wagon 

the G.V. 1000-pound delivery wagon, equipped with a single motor 
driving through a propeller shaft having two universals and with 
a David Brown (British) type of worm-gear rear axle. On machines 
of this class, it is customary to mount the motor on a flexible support, 
which permits it to adapt itself to variations in the angularity of 
the propeller shaft, thus reducing the load imposed on the universal 
joints and, at the same time, avoiding the effects of torsional stresses 
on the motor. As the location of the motor is such as to prevent 
the suspension of the battery below the frame in the usual cradle, 
it is carried forward under a bonnet, or hood, and the wheel-base of 



Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 11 



Fig. 4. G.M.C. Chassis with Combination Shaft and Chain Drive 

the chassis correspondingly lengthened. This is not the case with 
the Commercial worm-driven delivery wagon, as in this instance the 
motor is placed almost directly on the rear axle, as shown in Fig. 3, 
thus eliminating the propeller shaft and the necessity for universal 
joints. The spring suspension of the motor will be noted protruding 
above its forward end. 



Fig. 5. Motor, Drive Shaft, and Jackshaft Assembly for G.M.C. Electric Wagon 

Digitized by VjOOQIC 



12 COMMERCIAL VEHICLES 

Shaft and Chain Transmission. The G.M.C. (General Motors 
Company) electric embodies a combination of shaft and chain drive, 
as shown by the chassis, Fig. 4. This drive incorporates an ingenious 



Fig. 6. Details of Motor Mounting, Brake, and Drive, G.M.C. Electric Delivery Wagon 

feature consisting of the use of a spring steel shaft, as shown by the 
detail view, Fig. 5. The design of these cars, as shown by the chassis, 
is standard for all capacities ranging from a 1000-pound delivery 



Fig. 7. Chassis of Waverley 5-Ton Electric Track, Showing Battery Installation 

wagon up to a 6-ton truck, and, in each case, the section of this shaft 
is calculated to transmit the power necessary, with a predetermined 
degree of flexure in starting, which serves to cushion the mechanism 

Digitized by VjOOQIC 



COMMERCIAL VEHICLES 18 

as well as the tires. The pin attachment at the motor and the bevel- 
gear-driven countershaft eliminate the necessity for universal joints 
in this member while still permitting a rigid mounting of the motor 
on its sub-frame. As will be noted in Fig. 6, which shows the details 
of the complete drive, this sub-frame is carried in bearings on a 
tubular transverse member, thus allowing for relative movement in a 
longitudinal plane, the shaft itself compensating for torsional stresses. 
Unit-Wheel Drives. Mention has already been made of the 
abandonment of two-motor drives on comparatively light cars, as 
well as the successful employment of a single motor on vehicles up 
to 5 tons' capacity, as in the case of the Waverley 5-ton chassis, 



Fig. 8. Two-Motor Axle with Spur-Gear Drive, Commercial 2-Ton Truck 

Fig, 7. The Commercial electric is an exception to this in that it 
shows the successful employment of two motors on cars as small as 
one-ton capacity. The rear axle of this car is a complete self- 
contained unit, as will be seen upon referring to Fig. 8 illustrating 
the drive of a 2-ton Commercial. The form of mounting employed 
is clear in the illustration, while Fig. 9 shows the details of the gear 
reduction between the motor and the driving wheel. This concern 
also makes a four-wheel drive, which is employed on vehicles of 3 J to 
7 tons' capacity. On these machines, both front and rear axles are 
alike. One of them is illustrated in Fig. 10, in which it will be noted 
that the motor and the driving wheel are an integral unit pivoted in 

193 



14 COMMERCIAL VEHICLES 

the axle to permit of utilizing all four wheels for steering. The speed 
reduction in this instance is simply a double spur-gear train meshing 
with an internal gear cut on a drum in the rear wheel. 

Couple-Gear Truck Drive. A particularly ingenious example of 
the ease and directness with which electricity lends itself to special 



Fig. 9. View of Spur-Gear Reduction of Commercial Electric Drive 

forms of construction is to be found in the drive of the Couple-Gear 
truck, so called because all four wheels are not only driven by electric 



Fig. 10. Two-Motor Axle of Four-Wheel Drive of Commercial Heavy Trucks 

motors but are utilized for steering purposes. These vehicles are 
built as straight electrics, using a storage battery as the source of 



194 



Digitized by VjOOQIC 



COMMERCIAL VEHICLES 15 

current; and as gas-electric vehicles, a gasoline engine and generator 
forming the power plant, the remainder of the design and construc- 
tion being the same in both cases. Fig. 11 illustrates the detail of 
the axle design employed, each wheel being carried on a steering 



, Fig. 11. Couple-Gear Axle for Unit-Wheel Drive 

spindle, and all four wheels coupled to act in unison, permitting the 
car to turn in a very short radius. The parts shown on the right- 
hand spindle in the illustration are the fields of the motor, the wind- 



Fig. 12. Dismounted Couple-Gear Truck Wheel, Showing Motor Parts 

ings being just visible in the armature tunnel. They are made in 
this form, as the motor is practically a part of the wheel. 

The motor is built directly into the wheel, as will be apparent 
from the illustration of a dismounted wheel shown in Fig. 12. The 



195 



16 COMMERCIAL VEHICLES 

motor is of bipolar type, designed with flat fields in order that it may 
fit within the wheel without unduly increasing its section, and is held 
by its attachment to the axle. The wheel accordingly revolves about 
the motor, being driven by the two small pinions which are noticeable 
on opposite ends of the armature shaft and which mesh with the 
circular racks attached to the periphery of the wheel. The brushes 
are carried in a yoke bolted to the outer half of the field casting, so 



Fig. 13. Walker Electric Chassis, Showing Combined Motor Axle 

that the removal of the latter makes everything accessible. The 
cables for the motor current are led through the hollow axle. Apart 
from this feature and the employment of a four-wheel steer, the 
vehicle itself follows more or less conventional lines. 

Balanced Drive. The transmission on the Walker cars, known 
as a "balanced drive", is another radical departure from current 
practice in this respect. These cars are built in capacities ranging 
from 750 to 7000 pounds and have been in successful service for a 



19S 



Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 17 

number of years. As will be noted in Fig. 13, a single motor is 
employed, and it is built practically as an integral part of the rear 
axle, the housings of which form the fields. The armature of the 
motor is at right angles to the driving wheels, and its shaft is extended 
both ways to form the drive. At the outer ends, this shaft carries 
small spur pinions which mesh with two large gears. The latter, 



Fig. 14. Details of Walker Electric Wheel Drive 

in turn, mesh with an internal gear bolted to the inner face of the steel 
rims of the driving wheels themselves. The detail of this is made 
plain in Fig. 14, showing one of the wheels with the outer protecting 
disc removed. It will be apparent that this constitutes not only 
an unusually compact motor unit and transmission, having the great 
advantage of being always in direct line with its drive, but that it 
likewise dispenses with a differential, as the wheels themselves are 
balance gears. 

Digitized by VjOOQ IC 



18 COMMERCIAL VEHICLES 

CURRENT AND CURRENT CONTROL 
Battery Equipment. As the motors commonly employed are 
wound to take current at 80 to 85 volts, the battery consists of 44 
cells, divided into three or four groups of cells held in separate oak 
boxes, or "trays", as they are termed, to facilitate handling. This 
voltage is standard, regardless of the size of the vehicle, the latter 
being compensated for by changing the capacity of the battery. 
Thus, for light delivery wagons, each cell contains three positive and 
four negative plates of medium size, giving an 85-ampere-hour dis- 
charge capacity, while a 1000-pound wagon is equipped with a bat- 
tery having nine-plate cells with a capacity of 112 ampere hours; a 
2000-pound wagon, eleven-plate cells of larger dimensions, giving 
140 ampere hours; and so on in accordance with the size of the 
vehicle and the load it is designed to carry. Most electric vehicles 
have the battery underslung, i.e., carried in a cradle supported from 
the frame of the chassis. The cradle is enclosed in a battery box for 
protection against mud and water and has hinged doors at the ends 
through which the battery may be introduced or removed. By this 
arrangement, the weight of the battery, which is the heaviest single 
item in the entire construction, is distributed evenly between the 
forward and rear wheels, which leaves the entire floor space of the 
wagon available for the load. In special types, such as the G.V. 
1000-pound worm-driven delivery wagon, the usual practice in the 
pleasure-car method of carrying the battery under a hood forward is 
followed. All the wiring between the battery, controller, and motor 
is carried beneath the floor and is protected from injury by running 
it through iron conduits. 

Controller. In the case of delivery wagons and light trucks, 
the controller itself is placed either beneath the seat or under the 
footboards and is similar in construction to those employed on street 
cars, but much smaller in size, owing to the low voltage and com- 
paratively small amount of current to be handled. It is operated by 
a small hand lever and usually provides four speeds ahead and two 
reverse, all of which are obtainable by moving the same lever, 
although a special lock, or catch, must first be operated before the 
vehicle can be moved backward. This usually takes the form of a 
pedal, or kick plate, which may be depressed with the heel and must 
frequently be held down while reversing. When released, it auto- 
Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 19 

matically returns the controller to the ahead position, in order to 
prevent the vehicle from being backed inadvertently. 

Departures from the usual method of placing the controller are 
to be found in some of the medium-capacity vehicles, such as the 
Baker, in which the controller is located on the steering column just 
below the footboards; in the Urban, it is placed in a special dash 
compartment, the lever being on the steering wheel. This compart- 
ment also contains the ampere-hour meter, a type of instrument 
which records in watt hours the amount of power drawn from the 
battery and, at the same time, 
indicates the available amount 
remaining at any time. Ampere- 
hour meters are coming more and 
more into general use on both 
pleasure and commercial electrics, 
and a detailed description of the 
instrument and its use is given 
in connection with electric pleas- 
ure cars. In service, this dash 
compartment is protected by an 
aluminum plate through which 
the dial of the meter appears. On 
the Commercial, the controller is 
mounted directly on the steering 
column and is operated by a sec- 
ond smaller wheel, Fig. 15. The 

. 11 *x if • ii i. J.Y. F*£« 15. Commercial Electric Controller on 

Controller ltselt IS thus above the Steering Column 

footboards, and by the removal 

of the protective housing shown becomes very accessible. In cases 
where it is necessary to provide for handling heavy currents, a 
railway type of controller is employed. 

A novel controller installation that gives instant accessibility is 
found on the G.M.C., as shown in Fig. 16. The controller proper, 
as well as all wiring terminals, fuses, and meters are mounted under 
a short hood, the resistance being suspended just beneath the con- 
troller, while the charging receptacle is below the center of the bumper. 
This view illustrates the forward side of the dash, while Fig. 17 shows 
the side facing the driver. The connection between the control lever 

199 



20 COMMERCIAL VEHICLES 

over the steering wheel and the controller is through a shaft and 
a bevel gearing, as shown in Fig. 16. In the illustrations, this lever is 



Fig. 16. Controller Installation of G.M.C. Electric Delivery Wagon 

at the neutral position, successive movement from this point forward 
giving five speeds ahead and two reverse speeds backward. The 



Fig. 17. Simple Control of G.M.C. Electric 



G.V. control is equally compact, being mounted in a steel box form- 
ing the driver's seat, as shown in Fig. 18. The safety switch and 



200 



COMMERCIAL VEHICLES 21 

the plug connection for an inspection lamp are seen on the outside at 
the left. Inside are, first, the switch connections, then the fuses, and, 
next, the fingers of the controller. At the upper right hand (driver's 
left) is the control lever, while just visible below the box is the 
resistance. 

Safety Devices. In view of the fact that the average driver of 
an electric delivery wagon or a truck is either a graduate from the 
reins or has had no experience in handling vehicles at all, it has 
become customary to provide safety devices which, to a large extent, 



Fig. 18. Controller Box of G. V. Electric Delivery Wagon 

/ 

prevent accidents that might otherwise result from this lack of 
experience. 

Cvt-Ovt Switch Connected to Brake. The brake is usually inter- 
connected with a cut-out switch which automatically shuts off the 
power independently of the controller simply by the application of 
the former. While the brakes are sufficiently powerful to stop the 
machine even with the current on, forgetting to shut off the current 
would either blow out the fuses or result disastrously to the motor. 

Circuit-Breaker and Hand Sivitch. A circuit-breaker is provided 
on some cars to obviate the necessity for frequent replacing of the 
fuses, this being the usual practice in street railway and other electric 
work. Frequently, a hand-operated cut-out switch is also installed 



201 



22 COMMERCIAL VEHICLES 

to permit of inspecting or working on the controller without the 
necessity of disconnecting the battery, as a failure to do so where 
no switch is provided is apt to result in painful burns, owing to the 
large amount of current. 

Charging Circuit- Breaker. Another safeguard is an automati- 
cally operated circuit-breaker to protect the battery from being 
overcharged. This is used in connection with the Sangamo ampere- 
hour meter, which is described under the head of "Meters". Unlike 
the Anderson device described previously, which can be employed 
only where connection can be had to the field coils of the generator, 
this circuit-breaker operates exactly the same as the circuit-breaker 
in a generating station, which opens the line when an excess amount 
of current passes through it, except that in this case its operation is 
not controlled by the number of ampere turns on the circuit-breaker 
itself, but by a trip switch actuated by the ampere-hour meter when 
its dial records that the battery is fully charged. 

Devices to Prevent Accidental Starting or Tampering. Devices 
are provided to prevent the accidental starting of the vehicle when 
not anticipated by the driver; also to guard against tampering by 
the ubiquitous small boy. On the G.V. 1000-pound worm-driven 
delivery wagon, for example, the emergency brake cannot be locked 
on except when the "running switch" is in either the neutral or the 
charging position, and cannot be released until thrown into the run- 
ning position. Moreover, this switch can be thrown to the running 
position only when the controller is at the "off" point, or neutral 
position. The interconnection of the brakes and the controller 
"throw-off" allows the driver to use both hands for steering, in an 
emergency and, at the same time, to cut off the power and apply 
both brakes with his feet. This emergency-brake lock compels the 
driver to turn off the current by throwing the running switch to 
neutral when leaving the car; it also prevents the brake from being" 
released by an unauthorized person, as the driver can take the switch 
handle with him. As the brake cannot be released until the switch 
is thrown on, the driver is reminded of that fact. The running- 
switch lock prevents the accidental starting of the vehicle, which 
might happen if the controller had been tampered with during Jthe 
driver's absence, and if, upon his return, he threw the running switch 
on without first looking at the controller handle. 

202 



COMMERCIAL VEHICLES 23 

Brakes. Owing to the comparatively low speeds, the braking 
equipment in the earlier designs usually consisted of a single set of 
drums attached to the driving wheels. Against the inner faces of 
these steel drums bronze shoes were expanded by means of a pedal 
and the usual brake rigging beneath the car. As was the case in 
practically all early chain-driven cars, the braking drums carried the 
driving sprockets on their outer faces. 

But in this, as in many other essentials, practice has been 
improved along the lines followed in the gasoline car. It is now cus- 
tomary to employ two sets of brakes, one for regular service and one 
for emergencies. Usually, both sets of brakes are carried in drums 
on the driving wheels, either side by side or concentrically, a friction 
facing of asbestos on a woven-wire foundation being employed. In 
some cases, the service brake operates on a drum carried on the 
armature shaft of the motor. 

Tires. While solid rubber tires are most generally employed, 
they are not necessarily so, as pneumatic tires are to be preferred 
where the merchandise to be carried is of a light or fragile nature 
or where speed is one of the chief features of the delivery service. 
They not only reduce the liability to breakage, but also lessen the 
cost of maintaining the vehicle in repair. However, as there are 
comparatively few branches of commercial service in which the pneu- 
matic tire is economically practicable, its use is very limited. The 
solid tires employed vary in size from two to four inches, and for 
weights in excess of the capacity of the latter, they are used in twin 
form on the rear wheels. 

SPECIAL FORMS OF THE ELECTRIC 

Electric Tractors. The huge street-cleaning or garbage-removal 
truck, shown in Fig. 19, is drawn by a 5-ton G.V. electric tractor, 
the combination being along lines somewhat similar to the front- 
driven electrics adopted by the Paris street-cleaning department for 
the same purpose, except that the latter have a two-wheel tractor 
and are fitted with a specially designed covered steel body. One use 
of the electric tractor built along the lines just referred to is shown 
by the Couple-Gear propelled steam fire engine, Fig. 20. Part of 
the battery is carried on the frame and the remainder is suspended 
beneath it, the power consisting of two Couple-Gear motor wheels 



,Goosk 



Digitized by VjOOQI 



24 COMMERCIAL VEHICLES 



Fig. 19. Five-Ton G. V. Electric Tractor Hauling Garbage Wagon 

mounted on steering spindles and operated by a street-railway type 
of controller which will be noted at the left of the driver. The entire 
power plant is a comple'te unit, which is bolted directly to the engine 
without further alteration than the removal of its front truck. 



Fig. 20. Couple-Gear Tractor Drawing Steam Fire Engine 

Digitized by VjOOQiC 



COMMERCIAL VEHICLES 25 

Industrial Trucks. One of the most important developments 
of the past few years has been the widespread adoption of the so-called 
industrial truck. In a broad sense, the term represents a classification 
rather than a type, as there are several different types of chassis built 
for this purpose. Probably the first of these to be placed in service 
was the Lansden dock truck, designed for handling cargo on steam- 
ship piers. In addition to this, there are baggage and mail trucks for 
use in railway depots, also truck cranes and tractor trucks, and it will 
be apparent that they are designed for service where no other form of 
power than electricity would be either convenient or permitted. The 
battery truck crane, the baggage truck, and the tractor trucks are 
merely modifications of the simple freight truck, their functions vary- 
ing somewhat in each case. The baggage truck has a field of its own 
in the handling of baggage and mail, some being of the drop-frame and 
double-platform type and others having the battery and mechanism 
placed below the loading platform, which is made of railway-car 
height. 

The simple industrial, or freight, truck is built in sizes and capaci- 
ties suitable for moving loads on piers, in freight sheds, warehouses, 
factories, and industrial establishments generally. Its short wheel- 
base permits it to pass through congested spaces, going backward or 
forward with the same facility, while it is capable of ascending gradi- 
ents of 10 to 25 per cent. On piers and at railway terminals it can 
deliver its load on the deck of a vessel or in a box car. The capacity 
of such trucks seldom exceeds 2000 pounds, this figure being found 
the practical limit for trucks capable of the widest range of action. 
The loading space of a truck of this capacity is 28 square feet, while ' 
the total area required for movement is only 34 square feet, the 
machine having an extreme width of 4 feet and an extreme length 
of 8 feet, so that an industrial truck can be operated wherever a hand 
truck can go, while the former will ascend grades impossible to the 
latter. 

Fig. 21 shows a standard G.V. 2000-pound industrial truck, of 
which there are several hundred in use. Both the battery and the 
driving mechanism are suspended below the platform, which has 
rounded corners and is extended to protect the mechanism at every 
point. Its speed on hard level surfaces is 7 miles per hour; its average 
radius, 25 miles on one charge of the battery, the current consumption 

- .-• 205 ■ Digitized by G00gk 



26 COMMERCIAL VEHICLES 

for a full charge amounting to 6 to 8 kilowatt hours. For grades up 
to 10 per cent, only one motor is employed. When equipped with 
two motors, each rear wheel is driven by an individual motor geared 
to a housed spur gear fastened to the wheel. A spring-returned con- 
troller is used, the operating lever returning to neutral when released 
by the driver. The brake is also spring-operated and is normally set, 
so that in order to run the car the driver must keep the brake pedal 
depressed. A further safety precaution is an automatic cut-off 



Fig. 21. G.V. One-Ton Industrial Truck Handling Freight 

switch connected with the brake, so that in releasing the pedal of the 
latter the power is cut off automatically. In addition to this pedal, 
two operating handles are provided, one for the controller and the 
other for steering, the truck being capable of turning around in a 
7-foot radius. In general freight-shifting service, the hauls averaging 
from 200 to 800 feet, each truck displaces from four to six men with 
hand trucks. The efficiency of these trucks is frequently increased by 
using them in connection with trailers and large numbers are employed 
in factories for transporting material from one department to another. 

206 



COMMERCIAL VEHICLES 27 

ELECTRIC TRUCKS 

Classification. There is little, if any, difference in design between 
delivery wagons and trucks, the frames, axles, wheels, springs, and 
transmission simply being made heavier in proportion to the great 
increase in load to be carried, while there is a corresponding difference 
in the power of the motor or motors and in the size of the chains or 
other essentials of the transmission. As already mentioned, some 
makes, such as the Walker, adhere to the single-motor power plant 
even in sizes up to 2 and 3? tons' capacity, and the G.V., Lansden, 
Waverly, and G.M.C., up to 5 and 6 tons, on the score of increased 
economy and higher efficiency, while others, such as the Commercial, 
employ two motors on vehicles as small as the 4000-pound size and 
four motors on larger trucks. 

Next to the delivery wagon, in which electric power has scored a 
great success, trucks of 2-ton and 3-ton capacity are the most com- 
mon forms of electric vehicles — though the 5-ton size has come into 
general use for brewery service — several hundred being run by brewers 
in New York, while one St. Louis company has nearly a hundred. 
Electric trucks of 6- and 7-ton capacity are also built. In order to 
obtain the increase in load-carrying capacity, the size of the motor 
must naturally be enlarged, with a corresponding increase in the power 
consumption, which calls for a very much larger battery. In order 
that the capacity of the battery may be sufficient to give the vehicle 
a practical radius of travel on a single charge without unduly adding 
to the weight, the speed is reduced, so that electric trucks of 2-ton 
capacity usually have an average speed of 8 to 10 miles an hour; 
3-ton trucks, 6 to 9 miles an hour; while 5-ton trucks seldom exceed 
7 miles an hour. 

Characteristics of Chassis. The electrics listed by the General 
Vehicle Company afford an excellent example of a standard design 
of chassis applied to cars ranging from 1000 pounds up to 5 tons' 
capacity, the intermediate sizes being 2000 pounds, 2 tons, and Z\ 
tons. Naturally, the first two are delivery wagons and are capable 
of traveling 45 miles on a single charge of the battery at a maximum 
speed of 12 and 10 miles per hour, respectively. The 2-ton wagon, 
while capable of the same mileage, has & maximum speed of but 9 
miles per hour. This is further reduced to 8 miles per hour for the 
3^-ton truck, which has a radius of 40 miles on a charge, while the 



207 



Digitized by VjOOQ IC 



28 COMMERCIAL VEHICLES 

5-ton truck travels only 7 miles an hour as a maximum and has an 
extreme radius of 35 miles on a charge. In every case, only a single 



Fig. 22. Rear View of G.V. 4000-Pound Chassis 

motor is used, and as the design in all other respects is also standard 
for all sizes, a description of the 4000-pound wagon will suffice. 



Fig. 23. General Electric Motor 

With the exception of the use of a single-motor drive, a large 
number of the parts employed are practically the same as those used 

208 



COMMERCIAL VEHICLES 29 

in other makes of electrics. The foundation of the entire car consists 
of a pressed-steel frame, to which are directly riveted the cradle for 



Fig. 24. Rear Axle of G.V. 2-Ton Truck 

carrying the battery, the spring hangers, and the supports for the 
countershaft bearings. 

A view of the complete chassis will be found in Fig. 2. 
The view is taken from above and illustrates every essential except 
the battery. At the rear are the semi-elliptic springs, the solid-steel 
axle, artillery wheels with solid rubber tires and large driven sprockets, 
driving chains, the single motor suspended from a transverse tubular 
member on the frame, the enclosed silent-chain drive from the motor 
to the countershaft, the wiring in conduits from the controller to the 
motor, and the countershaft with its radius rods to equalize and 
maintain its distance from the rear axle. These rods also serve to 



Fig. 25. Front Axle of G.V. 2-Ton Truck 



take the stresses of driving off the rear springs. Just in front of the 
countershaft is the steel cradle for the battery trays; at the left, that 
is, at the front of the truck, is the steering gear, forward axle, springs, 
and wheels. 



209 



Digitized by VjOOQ IC 



30 COMMERCIAL VEHICLES 

An excellent view of the entire bottom construction, which gives 
a clear idea of the arrangement of the power and the drive, is shown 
in Fig. 22, while the essentials comprising it are shown in detail in 
Figs. 23, 24, and 25. Fig. 23 is a G.E. multipolar, ironclad motor. 
Fig. 24 shows the rear axle, while the forward axle and its steering 
attachments are shown in Fig. 25. A 44-cell storage battery furnishes 
current at 85 volts, the motor being wound to operate economically 
at this voltage. The battery is in sectional form, in crates of such 
weight and size as to permit of easy removal or of replacement from 
either side of the vehicle. It is so arranged that it may be recharged 
without disturbing it; but, where two batteries are employed, a 
charged set may be easily and quickly substituted for the exhausted 
battery. 

The controller is of the continuous-torque type which will per- 
mit of changing the motor speeds by degrees without interrupting the 
power between any of the steps. This gives a gradual and steady 
acceleration, without the jerk and strain so detrimental to the life and 
efficiency of every part of the vehicle. The motor is designed along 
the lines which have proved so successful in street-railway work. It 
has a very heavy shaft as well as a simple and durable brush rigging 
and is wound to show not only a high efficiency but also a high capac- 
ity for overload. The armature shaft, which is carried on annular 
ball bearings that tend to greatly increase the efficiency of the motor 
as a whole, is suspended on a transverse bar pivoted to the side mem- 
bers of the frame forward of the rear axle. This pivoted suspension 
keeps the motor shaft parallel with the countershaft throughout the 
entire range of chain adjustment and permits the use of an efficient 
silent-chain drive, which, as will be noticed in Fig. 2, is enclosed in 
an aluminum housing. 

The countershaft is housed in and is carried on four taper-roller 
bearings inside the tube, the latter being held in self-aligning ball 
sleeves in hangers riveted to the sides of the frame. The two short 
driving shafts are connected by a spur differential and carry at their 
outer ends small sprockets for the roller chains to drive the rear 
wheels, the entire countershaft being a complete unit. It is driven by 
a silent chain of ample width running over a small pinion on the motor 
and over the gear of the differential. Altogether, this is a very effi- 
cient form of truck. 

Digitized by VjOOQ IC 



I COMMERCIAL VEHICLES 31 

GASOLINE VEHICLES 

GASOLINE DELIVERY WAGONS 

Classification Limits. It will be found on a brief examination of 
the subject that this is a far more comprehensive heading than would 
appear at first sight, as it includes everything from the little three- 
wheeler up to the type known as the "light truck", but which is, in 
reality, also a delivery wagon with an open platform, or stake type of 
body. The range of carrying capacity is from one to two hundred 



Fig. 26. Autocar Two-Cylinder Delivery Wagon 

pounds up to one ton, or slightly more, as many delivery wagons and 
light trucks are built with a load capacity of 2500 pounds or even 
3000 pounds. 

Autocar. The Autocar delivery wagon, Fig. 26, affords an excel- 
lent example of a vehicle designed especially for the most severe 
business conditions. The motor is of the two-cylinder, horizontal, 
opposed, four-cycle type, the cylinder dimensions being 4f-inch bore 
by 4§-inch stroke, and is rated at 18 horsepower. The crankshaft is 
mounted on imported annular ball bearings, which not only add 
greatly to the efficiency of the motor as a whole, but do away with the 
attention necessary to adjust plain bearings. This construction, 



Digitized by VjOOQ IC 



32 COMMERCIAL VEHICLES 

which is far more expensive than plain bearings, also reduces the 
number of parts which are subject to damage should the driver 
neglect to provide sufficient oil. The lubrication system is entirely 
automatic in operation. Two flywheels are carried on the crankshaft, 
the forward one having its blades cast staggered so as to set up a 
strong current of air, thus eliminating the necessity of a belt- or gear- ' 
driven fan, while the rear flywheel carries the clutch. The impor- 
tance of providing ample weight in the balance wheel is something to 
which insufficient attention has been devoted in the past, its influence 
upon the starting ability and the smooth-running qualities of the 
vehicle being extremely marked, especially where a two-cylinder motor 
is employed. Both flywheels on the Autocar motor are counter- 
weighted, and this, supplemented by a careful balance of all the 
reciprocating parts, makes an extremely smooth- and quiet-running 
motor with unusual starting and grade-climbing ability for its size. 

The crankcase is split horizontally into two sections, the lower 
half carrying the cylinders, crankshaft, camshaft, and water pump, 
while the upper half carries the push-rod guides, the magneto, the 
oiler, and a gear for driving the water pump. The magneto and 
oiler are both driven through bevel gears and short shafts,v reducing 
the possibility of failure in these two highly important essentials — 
ignition and lubrication — to a minimum. The upper section of the 
crankcase is readily removable, carrying its parts with it and thus 
giving access to the crankpin bearings without the necessity of 
dismantling the motor. A Bosch magneto with a fixed firing point 
is employed, thus taking this element of control out of the hands of 
the driver. Lubrication is by a force-feed oiler delivering oil through 
a sight feed to the crankcase, from which the pistons, crankpins, 
and main bearings are lubricated by splash. Both the magneto and 
the lubricator are simply attached to the crankcase by wing nuts 
so that they may be removed without the aid of tools. A hydraulic 
speed regulator, connected in the circulation circuit of the cooling 
water, controls a throttle placed in the intake manifold between the 
carburetor and the cylinders, limiting the speed of the motor to 1400 
r.p.m. and that of the vehicle to 18 to 20 miles per horn:. 

A patented floating-ring clutch, which has been developed on the 
same make of pleasure cars and used for a number of years, constitutes 
the first step in the transmission. It consists of a bronze floating 

212 Digitized by G00gle 



COMMERCIAL VEHICLES 33 

ring, lined with cork inserts on its inner face, and is mounted on four 
keys on the inside of the rim of the rear flywheel, thus rotating with 
the latter. Two cast- 
iron rings, adapted to 
clamp the bronze ring 
when the clutch is en- 
gaged, are mounted on 
the clutchshaft which 
extends into the trans- 
mission case. Engage- 
ment is accomplished by Fig< 27 ' Autocar D ° ubl *- Red » ction Floatin « R~ Axle 
a sliding trunnion and four toggle links, the motion of which is 
checked by a dashpot and a plunger. This insures gradual automatic 
action, entirely free from jerk, regardless of the care exercised by the 



Fig. 28. Rear View of Autocar Delivery Wagon 

driver. The addition of small springs to the floating ring eliminates 
all noise, whether the clutch be engaged or not. 



213 Digitized by G00gle 



34 COMMERCIAL VEHICLES 

The transmission housing is all in one piece, except its cover plate, 
and has been so designed that all the shafts and gears may be removed 
without disturbing the housing itself. The shafts are large and are 



Fig. 29. Autocar Engine and Transmission Mounted on Separate Sub-Frame 

carried on adjustable roller bearings, while the gears have broad faces 
and heavy teeth. Three speeds forward and one reverse, operating 
progressively, are provided, lubrication being obtained by covering 
the shafts and gears with a bath of semi-fluid oil. 



Fig. 30. Autocar Engine and Transmission — Plan View 

Both front and rear axles have been designed especially to meet 
the requirements of the heavy service imposed upon them in carrying 
the load on solid rubber tires. The front axle is of the tubular type, 

214 



COMMERCIAL VEHICLES 35 

with extra heavy yokes for the steering spindles, which are made 
integral with the spring saddles. Adjustable roller bearings are 
employed in the wheel hubs. The rear axle is of the full floating 
type, with a double-gear reduction. A bevel pinion at the end of the 
propeller shaft meshes with a large bevel gear on a short transverse 
shaft, from which the drive is transmitted to the differential case by 
means of a pair of substantial spur gears, the method of mounting 
them being shown by Fig. 27. The complete axle, as well as the 
spring suspension, the brakes, and other details are shown in the 
rear view, Fig. 28. 

One of the chief features of advantage on the Autocar delivery 
wagon is the mounting of the complete motor and transmission, 
barring the rear axle, on an independent sub-frame, as shown in Figs. 



Fig. 31. Plan View of White Delivery Wagon Chassis 

29 and 30. An illustration of the complete chassis would show every 
part of the power plant to be accessible by lifting the bonnet, while 
the complete unit, as shown separately, may be removed from the 
chassis and replaced by another. The rear view of the chassis, 
Fig. 28, shows the relative location of all the essential parts, including 
the gasoline tank, which is placed transversely on the main frame 
directly under the driver's seat. The frame is of pressed steel, 
perfectly rectangular and heavily reinforced. Two sets of brakes 
act on drums attached to the driving wheels, while the suspension 
consists of double-elliptic springs in the rear and semi-elliptic springs 
placed forward directly under the motor. 

White. This may be regarded as a representative standard 
design, as will be evident from the photo of the chassis, Fig. 31, show- 



215 



36 COMMERCIAL VEHICLES' 

ing that it differs from heavier-capacity vehicles^of the^same make 
only in being shaft-driven and having lighter dimensions. It is built 
in 1500- and 3000-pound sizes, the chassis illustrated being of the 
latter capacity. Single rear tires are usually fitted on the smaller 
car, and pneumatics are frequently employed to take advantage of the 
higher speed thus made possible, an example of this practice being 
illustrated by Fig. 32. Apart from the difference in dimensions and 
tire equipment, both sizes are the same, each being equipped with a 
3|- by 5^-inch motor, the cylinders of which are cast in one piece, 



Fig. 32. White Delivery Wagon with Light Top Body and Pneumatic Tires 

with the intake and exhaust passages integral. This motor is rated 
at 30 horsepower and fitted with a compression release for starting. 
A single-nozzle water-jacketed carburetor supplied with hot air from 
a jacket on the exhaust pipe, a high-tension magneto for ignition, 
and a gear-driven centrifugal water pump comprise its auxiliaries. 

GASOLINE TRUCKS 

Load Efficiency Increases with Size. It will be apparent that 
above the 2-ton size the load efficiency increases, as, once a certain 
point is reached, additions to the weight caused by increasing the 
dimensions of the load-carrying space and adding to the power of the 
motor are disproportionately small as compared with the increase in 

216 Digitized by G00gle 



COMMERCIAL VEHICLES 37 

load capacity. " For example, one truck of 3-ton capacity has a chassis 
weighing only 4500 pounds, which tips the scales at 5200 pounds 
completely fitted, or "all on"; on the other hand, another chassis 
for the same nominal carrying capacity, i.e., 3 tons, weighs 6000 
pounds. However, as no standard for rating the load-carrying 
capacity of gasoline trucks has ever been attempted, and one maker's 
5-ton truck is sometimes no larger than the 3-ton truck of another, 
it is often difficult to make comparisons that will be fair oh a basis of 
catalogue weights alone. 

MOTOR DETAILS 
Design 

Both the design and construction of internal-combustion motors 
for commercial use are along lines similar to those employed on 
pleasure automobiles except as modified by the requirements of 
the more severe service. This necessitates a higher factor of safety 
throughout, such as increased provision for lubrication and cooling; 
extra large bearing surfaces, which must be readily accessible for 
adjustment, except, of course, where antifriction bearings are 
employed; increased crankshaft dimensions; broad gear faces; and 
a considerably increased weight of flywheel in order that the motor 
may develop as high a torque as possible at low speeds. The greater 
amount of weight in the rim of the flywheel also eliminates motor 
vibration to a considerable extent and makes the engine run much 
more smoothly. Such variations of design as are usual in the pleasure- 
car motors are to be found in the commercial type; in fact, where a 
manufacturer builds both types, the same lines are followed in each 
case, the only practical difference being in the dimensions and speeds. 
It will be necessary, accordingly, to refer to only a few of the more 
representative makes. 

Long Stroke, Low Speed. Generally speaking, a commercial 
motor is of the long-stroke low-speed type, sonje idea of the propor- 
tions being obtainable by the dimensions of the White and the 
Pierce-Arrow motors for 5-ton trucks. The former has a 4J-inch 
bore by a 6f -inch stroke, while the latter measures 4| by 6 inches. 
Similar small variations in dimensions are to be noted in practically 
every make, in conformity with the Varying standards of compression 
and volumetric requirements adopted by their designers. This will 

Digitized by VjOOQ IC 



38 COMMERCIAL VEHICLES 

be apparent by a comparison of a few makes, such as the Locomobile, 
5 by 6 inches; G.V. and Mercedes, 4.25 by 5.9 inches; Peerless and 
Kelly, 4? by &\ inches; Vulcan, 4£ by b\ inches. No increase is made 
in motor dimensions above the 5-ton size, the extra carrying capacity 
being gained by higher gear reductions and lower speeds, the Vulcan 
motor mentioned being employed on both the 5- and 7-ton sizes of 
that make. These motors are variously rated at 35 to 40 horsepower, 



Fig. 33. Peerless 5-Ton Motor, T-Head Type 

viz, Vulcan, 36 horsepower; White, 40; Kelly, 38.5; Peerless, 32.4; 

Pierce- Arrow, 38. 

Causes of Variations in Ratings. The variation in the ratings 

is due to a number of causes, although one of the chief reasons is the 

differences in the practice followed, i.e., in some cases, the power 

stated is the maximum indicated horsepower based on the dimensions 

DXN 
and worked out by the S.A.E. formula of , in which D is the 

Z»o 

bore, N the number of cylinders, and 2.5 an arbitrary constant 

derived from taking the speed characteristics of a large number of 

motors and striking an average representing a piston speed of 1000 

feet per minute. In other cases, it is the result of actual brake tests 



218 



COMMERCIAL VEHICLES 39 



Fig. 34. White 40-Horeepower Block-Type Motor for 6-Ton Truck 



Fig. 35. Pierce-Arrow Motor for 5-Ton Truck 



219 



40 COMMERCIAL VEHICLES 

and is accordingly based on the maximum r.p.m. rate of the motor; 
while in still others it is the power which the motor is capable of 
developing at the speed at which it is controlled by the governor, 
usually 800 to 1000 r.p.m., to give the best service from the truck of 
the capacity for which it is designed. For instance, the rating of 
the Kelly motor is based on a speed of 900 r.p.m., while that of the 
Peerless, Fig. 33, of the same dimensions, is its indicated horsepower 
figured according to the above formula. The White motor, Fig. 34, 
is an example of the L-head type; while the Pierce- Arrow, Fig. 25, 
like the Peerless already mentioned, is of the T-head type. 

Accessories 

Ignition. In every department of commercial-car practice, the 
designer aims to make the operation of the machine as nearly auto- 
matic as possible and to that extent to relieve the driver of any 
opportunity to exercise his discretion. The usual practice is to 
employ a magneto fitted with an automatic spark-timing device. 
This operates on the principle of the centrifugal governor and is 
controlled entirely by the speed of the motor, so that when the motor 
is stopped the spark timing is fully retarded and there is no danger 
from a "back-kick" as is the case where this precaution is inadvertently 
overlooked. As the motor speed increases, the occurrence of the 
spark in the cylinders is automatically advanced to correspond, 
thus relieving the driver of this important function and preventing 
the abuse of the motor in unskilled hands. The same slight differ- 
ences in detail as found on the pleasure type are also found in the 
ignition systems of commercial cars. 

Carburetors. Carburetors also are the same both in principle 
and construction as on the pleasure cars, except in instances where 
they have been specially designed for commercial service, in which 
case the modification applies to the construction. In view of the 
very general custom in this country of leaving the design of auxiliaries 
to the accessory manufacturer, the number of these instances is very 
small, so that in the majority of cases the carburetor manufacturer 
sells the same carburetor for either type of vehicle. To permit of the 
efficient utilization of lower-grade fuels, ample provision is usually 
made for heating the carburetor by a large warm-water jacket and a 
supply of hot air taken from a collector located on the exhaust pipe. 

Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 41 

Cooling Systems. The so-called direct system, in which air is 
relied upon to keep the cylinder walls of the motor at a temperature 
that will permit of efficient operation without danger of seizing, 
was never attempted on commercial vehicles except in the lighter 
sizes. Most of these were light delivery wagons, although one make 
of 3-ton trucks employed a blower system for several years. How- 
ever, air as the cooling agent without an intermediary in the form of 
a water circulation has been definitely. abandoned on the commercial 
car. Both the principles and the operation are the same as on pleas- 
ure cars, due allowance being made for the more severe service by 
increasing the size of the pump, the* section of the cylinder jackets, 
the area of radiating surface, and the diameter of the connections. 

Radiator Construction. The radiator is the most vulnerable 
part of the truck, and precautions are therefore taken to protect 
it from injury. In order to be proof against the constant vibration 
and jolting, the gilled-tube type of radiator is employed in the 
majority of instances. Accidental damage is usually provided against 
by extending the frame and equipping it with a bumper, and further 
protection is sometimes afforded by mounting a heavy wire screen 
in front of it. This is done more frequently on honeycomb, or 
cellular, radiators, as they are liable to suffer severely when prodded 
with the steel-shod pole of a horse-drawn truck, and are difficult 
and expensive to repair. In the case of the gilled-tube type, only 
those tubes actually struck are likely to be damaged and they will 
frequently bend without rupture, while often nothing more serious 
happens than the bending and derangement of the cooling fins 
with which each tube is surrounded. These tubes are placed ver- 
tically and, in the case of the Reo 2-ton truck radiator, Fig. 36, 
are made demountable, so that a damaged tube may be easily replaced 
in a short time without the necessity for making any soldered repairs. 
It will be noted that each pair of tubes is held in place by a bolted 
yoke, so that upon loosening the yoke they may be lifted out. This 
illustration also clearly shows the flat copper tubes, which are placed 
with their narrow edges facing the air current, as well as the copper 
radiating fins attached to them. The upper and lower parts of the 
radiator are hollow castings, which form tanks, the sides merely 
providing a support and spacer for the tubes. The usual construction 
consists of a removable tank, which forms the top and bottom 

221 



42 COMMERCIAL VEHICLES 

chambers, with a bank of gilled tubes having their ends expanded 
and soldered into perforated plates, the solder playing an unim- 
portant part, as such joints cannot be relied upon where there is 
much vibration. 

Unless properly provided against, one of the chief sources of 
injury to the radiator arises out of the twisting of the frame under 
torsional stresses. Flexible joints between the radiator, and motor 
are accordingly necessary to take care of relative movement, and it is 

common practice, both 
in this country and 
abroad, to employ rubber 
hose for this purpose. 
By reason of the heavy 
loads carried and the use 
of solid tires, this precau- 
tion is not sufficient to 
guard the radiator 
against the effects of 
vibration and road 
shocks, so that it is usu- 
ally mounted on some 
kind of spring suspension. 
This spring suspension 

Pig. 36. Reo Demountable-Section GiUed-Tube Radiator USUally Consists of a pair 

of helical springs, one on 
either side, so that the radiator has no solid connection with its sup- 
port. In some instances, the radiator is hung on a pair of trunnions, 
similar to a gun mounting, but this form, while providing ample 
allowance for movement, does not cushion it against shocks. Still 
another method consists in mounting the radiator on an extension 
of the motor, the motor itself being carried on a three-point support, 
so that the radiator and motor move together; but, unless provided 
with some form of spring buffer between them, this type suffers 
from the same disadvantage as the one just mentioned. Figs. 37 
and 38 show some typical methods of radiator protection. 

Fans. In every case, the radiator is supplemented by a fan 
driven at high speed, and, in view of the slow travel of the heavier 
trucks, the proper working of the cooling system depends upon the 



222 



Digitized by VjOOQIC 



COMMERCIAL VEHICLES 



43 



efficiency of the fan, since the speed of the vehicle cannot force a 
strong draft of air through the radiator as it does in a touring 
car. Thus, the fan is a very important part of the cooling system 
on a slow-moving vehicle, as it 
must provide an ample draft, no 
matter how low the road speed 
may be, otherwise the engine is 
liable to heat beyond the point 
where the oil begins to lose its 
lubricating qualities. An ineffi- 
cient fan allows excessive heat- 
ing every time it is necessary to 
climb a long hill. 

Circulating Apparatus. In 
the majority"of cases, the cooling 




Fig. 37 



... White Radiator Mounting, Provid- 
ing Spring Cushioning and Relative 
Movement through Clevises 



water is circulated by a pump on commercial-car motors, though 
many heavy trucks, such as the Kelly-Springfield, have thermosiphon 
circulation. This pump is of the centrifugal type and is capable 
of delivering a much greater volume of water than are those employed 
on pleasure-car motors of corresponding power, owing to the reduced 
road speeds of trucks. These pumps vary more or less in design, 
but are based almost without exception on the centrifugal principle, 
as the latter is the only one which will permit of a thermosiphon 
circulation through it in case the impeller ceases to revolve. A 
stoppage of the gear type of pump also stops the circulation at once. 
Lubrication. Granting that an excess can be prevented from 
reaching the combustion chambers of the cylinders, it is axiomatic 
that the power plant of a motor 
truck cannot have too much oil. 
Ip. commercial service, the de- 
mands upon the lubricating sys- 
tem are quite as severe as they 
are upon the cooling system, and 
the failure of one usually involves 
the failure of the other in a short 
time. Hence, a greater amount 
of oil must be provided and every precaution taken to insure its 
reaching the bearings. Except for the increase in the quantity of 




Fig. 38. 



Front 



ng Hange 
it Hanger 



Bracket 



223 



Digitized by 



Google 



44 



COMMERCIAL VEHICLES 



lubricant, this does not differ in any way from the requirements of 
the pleasure car. Consequently, the systems employed are practically 
the same in both cases. The White lubrication system shown in 
Fig. 39 illustrates a typical sight -feed system. 

Motor Governors 

Of the two chief evils that beset the motor truck in the hands 
of the untrained driver — speeding and overloading — the former is 
the more destructive, as the driver who will overload his truck will 
also run at excessive speeds, and, with a heavy load, this is severe 
punishment for the entire mechanism. The practice became so 
common in the early days of the motor truck — nearly all drivers 




Fig. 39. Sight-Feed (Drop) Lubricating System as Used on White Trucks 

then being graduates from the pleasure-car field — that it has now 
become customary to govern the speed of the motor. The governor 
itself is usually sealed to prevent its being tampered with by the driver. 
General Charactefistics. The most generally accepted type as 
that of the usual centrifugal governor attached directly to the motor 
and operating a butterfly valve in the intake manifold between the 
regular carburetor throttle and the valve ports. Owing to the high 
motor speeds and the slight amount of movement necessary, the gover- 
nor is very small and compact, so that it will frequently be found incor- 
porated in the crankcase at the end of the camshaft. A variation 
from this is a drive taken from an outside auxiliary, such as the mag- 
neto shaft or water-pump shaft. In either case, the speed of the 



224 



Digitized by 



Google 



COMMERCIAL VEHICLES 45 

governor is always directly proportional to that of the motor itself 
and bears no relation to that of the vehicle. This is a disadvantage 
at times, as in pulling through a heavy road on low speed when the 
maximum power of which the motor is capable is required. 

Controlling Car Speed. An improvement on this practice has 
been the adoption of a vehicle "speed controller" which, while acting 
on the motor itself in the same manner as the usual motor governor, 
is controlled directly by the speed of the car and bears no relation to 
that of the engine. With this type, the motor is free to run at any 
speed at which the hand-operated throttle will supply it with fuel, 
so long as the speed of travel does not exceed that for which the 
governor, or controller, is set. So far as the motor is concerned, it is 
not directly governed and may be speeded up to any extent necessary 
to pull the car through heavy going or out of a ditch, as the controller 
does not come into action while the car is moving slowly. Practically, 
the only disadvantage of this type is the fact that it does not prevent 
the motor from racing, as does the former, when the load is suddenly 
removed, with the throttle open. The vehicle speed controller is 
driven either from one of the front wheels or from a shaft of the 
transmission, as its operation depends entirely upon the speed of 
the car. In addition to the centrifugal method of speed control, the 
hydraulic principle is also employed. It will be apparent that as 
the motor speed increases the circulation of the water, as driven 
by the pump, does likewise, and there is a corresponding rise in 
pressure in the cooling circulation. This rise in pressure is utilized 
to act on a large diaphragm connected with a plunger attached 
to a butterfly valve. A description of some of the governors in use 
will make clear the method of taking advantage of the different 
principles of operation. 

Centrifugal Type. In Fig. 40 is illustrated a typical centrifugal 
governor designed for attachment to one of the auxiliary shafts, as 
will be noted by the driving gears at the bottom. As the revolving 
weights tend to spread against the compression of the helical spring 
surrounding the spindle on which they revolve, they push up a yoke 
to which a shaft directly connected with the throttle valve is attached. 
As in the case of the steam engine, this valve is entirely independent 
of the hand-operated valve which may thus be left all the way open. 
The details of construction of the Pierce governor are shown by 

225 Digitized by G00gle 



46 



COMMERCIAL VEHICLES 



the sectional view, Fig. 41, in which the weights are at the right. 
As the triangular weights open under the centrifugal force generated, 
they push the rod forward, and, as this rod has a rack cut on it 




Section of Governor 
ond Driving Gears 



f rrorr Carburetor 
Intake Manifold Section 



Valve Operating 
Mechanism 



Fig. 40. Sectional Diagrams of Centrifugal Type of Governor 

that meshes with a pinion on the butterfly valve, this action tends 
to close the valve. A spring keeps this rod pressed against the 
spindle on which the weights are mounted, but is not connected with 
the spindle in any way. As is true of all governors in this service, 



Fig. 41. Sectional View of Pierce Centrifugal Motor Governor 

a speed adjustment and a method of sealing it against tampering 
are provided. 

Hydraulic Type. An example of the hydraulic type of governor 
is- shown in section in Fig. 42, while the application of this form of 
governor is illustrated by the Reo 2-ton truck motor, Fig. 43. As 



226 



Digitized by 



Google 



COMMERCIAL VEHICLES 



47 



will be seen in the section, this type consists of a water chamber, 
diaphragm, spring, and operating lever; the operating mechanism 



Water Chorriber 




Fig. 42. Hydraulic Type of Governor 



being combined with the 
governor proper results in 
a simple and compact 
unit which requires only 
one connection. This 
connection is led from the 
circulating system on the 
cold-water side, as will be 
noted in Fig. 43, in order 
to bring it close to the 
pump. As the speed of 
the pump increases, the 
pressure increases, and 
the diaphragm is forced 
down against the spring, 
carrying with it the lever 
operating the valve 



Fig. 43. 



Hydraulic Governor as Installed on Re© 2-To*i 
Truck Motor 



227 



Digitized by 



Google 



48 COMMERCIAL VEHICLES 

through a rack and a pinion. As the pressure decreases, the spring 
returns the diaphragm, and with it the valve, to its normal position. 
The water chamber, operating-lever housing, and the spring-retaining 
plug are sealed so that the adjustment cannot be varied without 
disturbing one of these seals. In this, as well as in the centrifugal 
type where the adjustment is effected by altering the tension of a 
spring, it will be obvious that the spring could readily be screwed 
up so tightly that no speed of which the motor was capable would 
have any effect on the governor, thus practically cutting out its 
action altogether. 

POWER TRANSMISSION DETAILS 
Clutch and Transmission 

Clutches. Cone Type. A comparison of the specifications of a 
number of representative makes of trucks reveals a variation in 
clutch design about equivalent to what would be found on an equal 
number of pleasure cars, except that a greater number of instances of 
the leather-faced cone occur in the trucks. This is the oldest type 
employed on the automobile and is likewise the simplest in construc- 
tion, which probably accounts for its more general retention in the 
commercial field. What is termed the direct conical type, in which 
the leather-faced cone engages by moving forward into the corre- 
sponding wedge-shaped recess of the flywheel, is in more general use 
than the indirect, or internal, cone in which the male member moves 
backward into engagement. An example of the latter type is found 
on the Peerless trucks, while the Garford, Kelly, Vulcan, Mais, and 
Pierce are representative of the former. In the case of the Pierce* 
the cone operates in an oil bath, the others running dry, as is more 
often the case. 

Multiple-Disc Type. The Packard and Autocar in this country 
and the De Dion in France have long been fitted with a three-plate 
type, the Albion (British) having a single-plate form of clutch in the 
heavier sizes. Multiple-disc clutches are found on the Locomobile, 
the Mack, and the Reo, and other American makes. 

Transmission. Owing to the great reduction in speed necessary 
between the motor and the driving wheels, transmission plays a 
more important part on the commercial vehicle than it does on the 
pleasure car. On the latter, its services can be dispensed with in an 

Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 49 

emergency, as the car can be started on the direct drive in case of 
accident to the intermediate speeds, but this would manifestly be 
impossible on a heavily loaded truck. In this connection, it is to be 
noted that the term ' 'transmission" has come to signify the "change- 
speed gearset" alone, doubtless owing to the awkwardness of the latter 
appellation, and does not apply to the transmission of the power 
from the motor to the rear or front wheels or to all four, as the case 
may be. 

Sliding-Gear Type. In the majority of instances, the sliding-gear 
type of transmission is employed for commercial work, in which the 
gears are actually slid into engagement with each other to effect 
the various ratios of driving and driven members. This type is 



Fig. 44. Type of Transmission Employed on White Shaft-Driven Trucks 

practically universal on the pleasure car, so that only a brief reference 
to it is necessary here. On almost all except the lighter vehicles, it 
provides four forward speeds, the others having but three speeds and 
reverse. Fig. 44 shows the White transmission as employed with 
a shaft drive. Owing to the controlling connections being absent, 
this has been inadvertently photographed with both the first, or 
lowest speed, and the direct, or highest speed, engaged. The large 
gear at the left, shown in engagement with its corresponding gear on 
the layshaft, gives the first speed. By moving it forward until the 
gear just ahead, with which it is integral, meshes with the next gear 
to the right on the layshaft, the second speed is obtained. Moving 
the single gear at the right back until it meshes with the right-hand 
gear of the pair on the layshaft gives third speed. For fourth speed, 

229 



50 COMMERCIAL VEHICLES 

or direct drive, this same gear is moved forward, its forward face 
being cut in the form of a dog clutch that engages a similar gear 
permanently attached to the clutchshaft. This is unusual, as the 
dog clutch is generally formed of a smaller diameter extension on 
the hub of the direct-drive gear. The two gears at the extreme right- 
hand end are permanently engaged and serve to drive the layshaft. 
By moving the largest gear to the extreme left, the reverse is engaged, 
this being effected through an intermediate pinion, or idler, part of 
which is just visible below the main shaft at that point. The moving 
members slide on splines cut on the main shaft, the sliding being 
sometimes effected by making the main shaft of square section. 



Fig. 45. Peerless Transmission and Countershaft 

A similar transmission, combined with a bevel drive and spur- 
gear differential on a jackshaft for side-chain final drive, is that of the 
Peerless, Fig. 45. This is shown engaged on the direct drive, so 
the dog clutch is not visible. The material used in the housing is 
usually aluminum, sometimes cast iron, and, in the case of the 
Locomobile, manganese bronze. Annular ball bearings are employed 
in many instances, the bearings themselves being apparent in the 
White transmission and their mountings in the Peerless. Taper 
roller bearings are also employed for the same purpose. Operation 
is almost invariably by the selective method, the gear lever being 
shifted across through a gate to pick up one or the other of the 
sliding members shown. The control lever of the White, which is 
mounted directly on the transmission housing, is shown in Fig. 46. 
This lever is more often mounted at the side in a fixture also carry- 
Digitized by vjOOQ Ic 



COMMERCIAL VEHICLES 51 

ing the emergency-brake lever, as on the Pierce. On this truck, 
only three forward speeds are provided. 

Mack Transmission. The Mack transmission, Fig. 47, is a 
selectively operated type in which the gears of the various speeds 
are always in mesh, small clutches being designed to slide in either 
direction on the squared main shaft, engaging the particular speed 
desired. These clutches are practically small gears which mesh 



Fig. 46. Completely Assembled White Transmission, Showing 
Control Lever 

with internal-gear members attached to the driving members. 
They will be noted lying between the driving gears on the main shaft, 
in the illustration. The gear housing in this case is of phosphor bronze. 
Use of "Dog" Clutches. A variation of the Mack type of trans- 
mission employs what are known as "dog" clutches, probably from 
the fact that they apparently bite into one another, being cut with 
a comparatively small number of heavy teeth on their end faces. 
These teeth, if they can be properly so-called, are of heavy section 



231 



52 COMMERCIAL VEHICLES 

and are cut with an easy angle which insures ready engagement. 
This will be noted in the direct-drive engagement of the White gear- 
set. The dog-clutch • type of gearset has been employed more in 
Great Britain than in this country. Its great advantages are that 
the driving gears are constantly in mesh and that the dog clutches 
can be engaged without particular attention being paid to the speed 
at which the two shafts are revolving, as is necessary with the sliding- 
gear type. The details of a transmission of this kind, as well as 



Fig. 47. Mack Transmission Used on Manhattan Trucks 

of the method of operation, are clearly shown in Fig. 48, which is a 
Cotta transmission designed for use on worm-driven trucks. As 
shown in the illustration, the first, or low, speed is engaged, the 
clutch on the layshaft at the lower right-hand corner being in mesh 
with its counterpart on the large, or low-speed, gear. The clutch- 
shaft being at the right-hand end of the gear box, as shown, the drive 
is then through the pinion on it, the large gear below, with w T hich 
it is in mesh, and then through the layshaft and the pair of gears 
at the left-hand end, these gears being fastened to ^eir respective 



232 Digitized by G00gk 



COMMERCIAL VEHICLES 53 

shafts. The other gears, with the exception of the clutchshaft 
pinion previously mentioned, are free to rotate on their shafts and 
are permanently in mesh. However, the male members of the 
individual clutches, while free to slide on the shafts, must turn with 
them, so that when engaged they "pick up" the various gears cor- 
responding to the different speeds. 

Silent-Chain Transmission. Another form of transmission, 
which has been used to a greater or less extent abroad, but which 
has found little favor here, is the silent-chain type. This is along 
similar lines to the Mack transmission illustrated, except that roller 
chains take the place of the permanently meshed gears, dog clutches 
being engaged to pick up the latter according to the speed desired. 

Final Drive 

Until v a few years ago, there was a sharp line of demarcation 
between the pleasure car and the commercial vehicle where the 



Fig. 48. Cotta Individual (Dog) Clutch Transmission 
Designed for Worm-Driven Trucks 

important. final drive was concerned. Practically all pleasure cars 
were shaft-driven, and, to the same extent, commercial cars were 
chain-driven. The tendency that has manifested itself in the interim 
makes it apparent that the history made in the development of the 
pleasure car is apt to repeat itself in commercial-car development. 
In other words, chain-driven trucks were largely in the majority 
a few years ago, but the recent advances made in live-axle construction 
have had a marked effect and their adoption has now reached such 
a scale that, barring something unforeseen, the chain on the truck 
will soon disappear as it has from the touring car. 

233 DfQitized.by G00gle 



54 COMMERCIAL VEHICLES 

Classification. As at present employed, there are four general 
classes of final drive on commercial cars. In the order of their age 
and present comparative importance, these are: first, the double 
side-chain from a centrally located countershaft carrying the differ- 
ential and the bevel drive, and usually combined with the gearset, or 
transmission, so called; second, the worm drive, which differs from 
the bevel-gear type only by the substitution of a worm and a worm 
wheel for the bevel gear and the pinion; third, the double-reduction 
live axle, in which a bevel-gear drive is employed in connection with 
a second reduction in speed through the spur gears; fourth, the so- 
called internal-drive rear axle, in which the first reduction is through 
the conventional bevel gear and the second is by means of a small 
spur pinion meshing with an internal gear cut on the inner face of a 
drum attached to the driving wheel. It may occasion some surprise 
to note in this connection that the worm drive is mentioned as being 
second in point of seniority, and further that no mention is made of 
the standard bevel-gear live axle. In the first place, the use of the 
worm on automobiles dates back to its employment on the Lan- 
chester pleasure cars in 1898 and its adoption on the Dennis busses 
in London in 1903, on which it has been regularly used ever since. 
No mention is made of the standard bevel-gear axle here, since the 
latter is only adapted for use on light cars. The higher speeds at 
which these vehicles run do not necessitate the employment of 
extremely high reduction ratios, so that a live axle of this type may be 
employed without having to make the bevel gear of a size that would 
seriously reduce road clearance, on the one hand; or a bevel pinion 
that would exceed the mechanical limitations of this form of drive, 
on the other. It is rarely employed, however, on vehicles of more 
than If tons' capacity, and the ease with which the entire speed 
reduction necessary may be carried out in a single step by means of 
a worm gear will doubtless make the straight bevel type obsolete 
on commercial vehicles within the next few years. 

Side-Chain Drive. Until the introduction in this country, at a ' 
comparatively recent date, of the worm drive, some form of double- 
reduction gearing has been used on all heavy motor trucks. The 
form most commonly used has been the double side-chain final drive, 
in which the primary gear reduction is obtained by means of a bevel 
gear driving the jackshaft and a secondary reduction in the chains 



Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 55 

and sprockets. This type of drive, utilizing roller chains, has been 
used on nearly all heavy motor trucks since the inception of the com- 
mercial vehicle. With but one or two exceptions, on all these 
trucks of American manufacture no attempt has been made to house 
the chains in, and they run exposed to dirt, mud, and water. 

Standard Types. A typical American side-chain drive for trucks 
of medium capacity is shown in Fig. 49, which illustrates a Timken 
unit. Except for the provision of brakes and sprockets at its outer 
ends instead of wheels, the countershaft, or jackshaft, is practically 



Fig. 49. Timken Standard Jackshaft for Side-Chain Drive 

a bevel-gear live axle. The rear axle is what is known as a "dead" 
axle in that it has no moving parts other than the wheels which 
revolve on bearings mounted on it. The two wheels are kept at a 
predetermined distance apart, and their parallelism is preserved by 
two distance, or radius, rods. A little consideration will make it plain 
that the thrust of repulsion against the ground of the driving wheels 
must be taken up on the vehicle before the latter can move, other- 
wise the rear axle would tend to travel forward independently until 
checked by the springs, which would then take the driving effort. 

235 



56 



COMMERCIAL VEHICLES 



This is frequently done on pleasure cars, and makes a flexible power 
transmission which is easy on the mechansim and the tires, but which 
is not practical with the heavy loads handled on trucks. Hence, the 
radius rods are employed to transmit this strain to the frame of 
the car, but, at the same time, they must provide for a certain amount 
of relative movement in both a vertical as well as a horizontal plane, 
besides affording a certain amount of flexibility. 

Radius and Torque Rods. Fig. 50, which represents a well- 
worked-out radius-rod design, illustrates how these various require- 
ments are met. Starting at the right-hand end of the rod which is 
attached to the rear axle, it will be seen that this design consists of 
a connecting-rod type of bearing that permits movement in a vertical 
plane, as this bearing is held on a tubular section of the axle and 




W 



MB® 




Fig, ,50. Flexible Universally Jointed Radius Rod for Double Side-Chain Drive 

is kept well lubricated. Just forward of the bearing is a heavy spindle 
which pivots the rest of the rod on the rear bearing, so that ample 
provision is made for lateral movement. The rod proper is in two 
parts held together by the compression of a heavy helical spring, which 
relieves the mechanism and tires of the initial thrust of starting, and 
also prevents shocks to the rear axle reaching the frame via the 
radius rod. Further provision for movement in a vertical plane is 
made by the attachment of the forward end of the rod to the frame, 
which forms a pivoted yoke. The threaded portion and the locked 
collar, noticed at the forward end, allow for adjustment in the length 
of the rodj this adjustment being provided for in the spring rod 
by the nut shown inside the yoke at the forward end. On shaft- 
driven carsy a torque rod is employed to take this thrust and also 
to +nke up the twisting effort, or "torque," of the propeller shaft. 



236 



Digitized by 



Google 



COMMERCIAL VEHICLES 57 

Speed Reduction. The rear axle proper is simply a drop forging 
of I-beam section representing the strongest and lightest cross- 
section for a beam. It is forged integral with the pads, or saddles, for 
attaching the springs and is machined to receive the wheel bearings 
and the bearings of the radius rods which complete its construction. 
The driving sprockets are bolted to the pressed-steel or cast-steel 
brake drums and the latter are in turn bolted to the wood artillery 
wheels. On trucks of two to seven tons' capacity, the speed reduc- 
tion between the motor and the rear wheels ranges all the way from 7 
to 1 to 14 or 15 to 1. The first step in the reduction is carried out in 



Fig. 51 . Rear of Packard 5-Ton Chassis, Showing Size of Driving Sprockets 

the bevel-gear drive of the countershaft and rarely exceeds 4 or 5 
to 1, as the use of a larger bevel would involve the use of a cumber- 
some and weighty housing. The remaining reduction is accom- 
plished by the difference in the driving and driven sprockets. How 
great this second reduction may be can be seen from Fig. 51, which 
is a rear view of a standard design of side-chain-driven heavy truck, 
the Packard. A study of this illustration will make clear several of 
the details of axle, spring, brake, and radius-rod construction 
described in previous paragraphs. 

Worm Drive. The worm gear was tried tentatively on steam 
traction engines in England as early as 1850, but it was not until 

237 



5S COMMERCIAL VEHICLES 

1S98, when it was applied to the driving of the Lanchester car, that 
it was seriously taken up for this purpose. The Lanchester worm is 
a peculiar variation of the more familiar Hindley type and is placed 
under the wheel to insure lubrication. An illustration of this worm 
gear will be found in the section devoted to the transmission of 
electric pleasure vehicles, as worm gears of this type are imported 
from England for use on the Detroit electric cars. The first rear- 
axle motor-truck drive of the worm type was a 3^-ton Dennis bus 






Fig. 52. Phantom View of Pierce Worm-Driven Rear Axle 

and quite a number of worm-driven Dennis busses have been in 
service in London for several years. Dennis was also the first to 
running in London. This was first put in service in 1903 and, though 
its introduction met with considerable opposition, it proved a success, 
mount the worm over the wheel, producing the so-called "overhead" 
type, which feature also came in for much criticism owing to its 
alleged failure to provide lubrication. It will be perfectly obvious 
that with the worm-wheel housing only partly full of oil this criticism 
would be unfounded, as the wheel acts as an excellent conveyor 
to carry the oil up to the worm. Eight years* use in London without 
failure of lubrication bears out this statement. 



Digitized by VjOOQIC 



COMMERCIAL VEHICLES 39 

Development The London General Omnibus Company was the 
first to design and manufacture on a large scale a new type of worm- 
gear axle in which the worm gear was mounted on a separate assem- 
bly. This design has superseded others until now, with some modi- 
fication, it is accepted practice. The worm and the wheel are 
mounted in a very rigid block and, with their bearings, housings, 
etc., form a complete unenclosed transmission unit, as seen in 
Fig. 52, which is a phantom view of the worm gear employed on the 



Fig. 53. Chassis of Pierce 5-Ton Worm-Driven Truck 

Pierce trucks, the makers of the latter having been the pioneers 
in introducing this type into the United States. This unit is dropped 
into the bowl-shaped rear-axle housing and bolted in place. This 
mounting lends itself readily to accurate machining, every part 
being open and easily accessible. This is also true of the unit as 
a whole where inspection, adjustment, and repair are concerned. 
This housing is of heavy construction and, as it is rigid, prevents 
road shocks or stresses, other than those coming through the driving 



239 



60 COMMERCIAL VEHICLES 

axles, from disturbing the alignment of the worm gear. The housings 
of the driving shafts, or axles, are tubular, and the shafts themselves 
are assembled through the tubes into the squared sockets in the 
differential. This makes a very accessible assembly as, by pulling 
out the driving axles and disconnecting the universal joint, the worm 
unit can be lifted out of its housing. The socket, with several 
keyways in it extending forward from the worm proper, i$ for the 
reception of the splined end of the propeller shaft from the gearset. 
This keyed socket is the slip end of the rear universal joint in the 
shaft line and is designed to prevent relative movement of rear axle 
and of gear set from imposing excessive stresses on the propeller shaft. 

The driving thrust and the torque are taken on a short heavy 
torque rod, which will be noted extending forward from the rear- 
axle housing just below the universal joint. This is a heavy drop 
forging and, as will be clear, is mounted on a heavy spindle at the 
axle housing, allowing for movement in a horizontal plane; while at 
its forward end, which is made in the form of a yoke, it is carried 
on a horizontal pin permitting a vertical movement to compensate 
for variations in the vertical distance between the axle and frame 
caused by the compression and recoil of the springs. Its location 
is made clear in the chassis view, Fig. 53. 

Fig. 54 shows the form of mounting adopted by the Timken 
Company for the David Brown type of worm drive which they 
manufacture. This is the same as that employed on the Pierce 
trucks, but both the method of mounting and the bearings differ. 
The Timken Company use their own taper roller bearings, while the 
Pierce Company use annular ball bearings. The worm is of the 
so-called straight type, meaning that it is of uniform diameter 
throughout its length as distinguished from the "hourglass" type. 

Standard Types of Worm Gears. In the straight type, the worm 
is cylindrical through its entire length, and the worm wheel into 
which it meshes is concave. In the hourglass type, both worm and 
worm wheel are concave. The advantage claimed for the latter 
form is the greater area of engagement, thus spreading the driving 
strain over a greater number of teeth and reducing the pressure on 
the surface of both. On this type, however, there is only one position 
in which the worm and the worm wheel can be located with respect 
to each other in order to take advantage of this greater area of con- 

240 

Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 61 

tact, while on the straight type it is necessary only to locate the worm 
correctly, with respect to the worm wheel, in one direction, since the 
worm is cylindrical and uniform in diameter throughout its entire 
length. The straight type is therefore much less liable to damage 
through misalignment. With the hourglass type, a slight misplace- 
ment in any direction is liable to prove fatal, so that the chances of 
trouble in practical operation are greatly reduced in the straight type. 
Efficiency of Worm Gears. In an elaborate test of three differ- 
ent types of worm gears (by types in this connection being meant 



Fig. 54. David Brown Type of Worm Gear as Mounted on Timken Axle 

differences in tooth form and pitch) made at the Brown and Sharpe 
plant to determine which form was best adapted to automobile use, 
efficiencies ranging from 90.2 to 95.5 were obtained on the first speed, 
91.3 to 93.4 per cent on the second speed, and 90.1 to 97.6 per cent 
on the direct drive. The results obtained with a bevel-gear-drive 
test made for comparison were 91.4 to 96.6 per cent on first speed, 
94.5 to 99.3 on second, and 94.0 to 99.2 on direct drive. So far as 
the life of the worm is concerned, mileage records obtained on com- 
mercial cars range from 40,000 to 110,000 miles, the lower figure 

Digitized by VjOOQ IC 



62 COMMERCIAL VEHICLES 

being considered only fair for a well-made straight type of worm; 
while, on pleasure cars, three years of constant service was not 
thought at all unusual. 

Double-Reduction Live Axle. As sufficient drop in speed can- 
not be had with a bevel gear through a single reduction without 
making the driven bevel gear of impracticable proportions, thus 
involving excessive weight in the rear-axle housing and a dangerous 
lack of clearance between the latter and the ground, an intermediate 
spur reduction is introduced just forward of the bevel gears. One 
method of accomplishing this is illustrated by Fig. 55, which shows 
the extra speed reduction combined in the same housing as the 
differential and the bevel drive, an extra cover plate making it 
accessible. It will be noted that helical-cut gears are employed 



Fig. 55. White Differential, Showing Second-Reduction Gear 

instead of the straight-spur type, this form of tooth giving greater 
bearing surface, closer engagement, i.e., less backlash, or lost motion, 
between the gears and far less noise in running. Another form of 
double-reduction axle is the special type developed on the Autocar 
delivery wagon and illustrated in connection with the description of 
that vehicle. 

Internal Gear-Driven Axle. The internal gear-driven type of 
axle is another form of final drive that has been introduced in this 
country after a long and successful record abroad. Like the worm 
gear, it aspires to the honor of replacing the side chains and, like that 
form, also has already made considerable progress in this direction. 
In principle, this form of drive consists of making the driving axles in- 
dependent of, and external to, the rear axle proper, which, in this case, 

Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 63 

is of the "dead" type, usually a solid section, such as a square or an 
I-beam forging. Its function is merely to carry the weight of the 
car, although it also is made to serve both as a support and as a rein- 
forcement for the live axle. In the case of the Mercedes (German) 
trucks, on which it has been used since 1900, the driving axle is 
placed forward of the dead axle. At their outer ends, the shafts of 
the latter carry small spur pinions which mesh with large internal 
gears cut on rings attached to drums on the rear wheels. One of 
these wheels and the driving pinion on the end of the live shaft are 
illustrated in Fig. 56, which shows this construction as carried Out 
on an American-built replica of the German truck in question. 

This same form of axle has been employed also for a number of 
years in Paris by the builders of the De Dion cars for their commer- 
cial types, chiefly busses. In this case, the live axle is carried above 



Fig. 56. Mercedes (German) Internal Gear Drive, Showing Principle of Action and 
Assembled Rear Wheel 

its support. More than a hundred of these busses have been in 
service in New York for several years and, as more are ordered 
from time to time to meet the increasing requirements, it must be 
concluded that they have been satisfactory. The builders of the Mais 
trucks were doubtless the pioneers in the commercial use of this form 
of axle in this country, and the Mais internal gear-driven rear axle is 
probably the form in which this type is most generally used. In this 
case, the driving axle is placed forward of the dead axle. Upon com- 
paring the size of the driving pinion at the rear wheel with the internal 
gear, it will be apparent that a very large gear reduction is conven- 
iently obtainable by this method without in any way interfering with 
the road clearance of the vehicle. The first reduction consists, of 
course, in every case, of the conventional bevel-gear drive, but, as will 
be noted from the part sectional views of the Torbensen and Garford 



243 

-Digitized by 



Google 



64 



COMMERCIAL VEHICLES 



types of internal gear-driven axles, as shown in Figs. 57 and 58, there 
is very little reduction between the bevel pinion and its gear. This 
decreases the amount of leverage the pinion has to exert and conse- 




Fig. 57. Torbensen Internal Gear-Driven Rear Axle 

quently decreases the tooth pressure in proportion. In the Torben- 
sen axle, the live member, or countershaft, is placed to the rear of the 
I-beam supporting member, while in the Garford this is reversed. On 
the Jeflfery "Quad", it is placed directly over the wheel support, as 



Fig. 58. Garford Internal Gear-Driven Rear Axle 

shown by Fig. 59, which illustrates the driving pinion and the wheel 
with its internal gear. As this truck steers, drives, and brakes on all 
four wheels, a universal joint is placed directly behind the pinion. 
Fig. 60 shows the wheel and its gear ready for mounting. A some- 



244 



Digitized by 



Google 



COMMERCIAL VEHICLES 65 

what similar design is found on the Christie front-drive tractor for fire 
apparatus, with the added distinction that on this machine only the 
rim of the driving wheel revolves and is carried on a ball bearing 
which is practically the size of the wheel itself. On the Jeffery, the 
wheel revolves on the two taper roller bearings shown. 

Differential Lock. The function of the differential, balance gear, 
or compensating gear, as it is variously called, is naturally the same 
on the commercial vehicle as it is on the pleasure car, i.e., that of 
permitting one wheel to run free in rounding a turn so that it may 
travel the greater distance represented by the outside circle in the 
same time that the inner 
takes to traverse its orbit ; 
but the differential has 
the unfortunate draw- 
back of not permitting 
any power to reach one 
of the driving w T heels in 
case it is held while the 
other is free. This fre- 
quently occurs where the 
truck settles into a ditch 
or extra deep rut in a 
soft road, leaving the 
other wheel more or less 
in the air. Under such 
conditions the entire 

power goes tO the free Fig. 59. Jeffery Rear-Axle Driving Mechanism 

. . 1 • A i 1 an d Bearings 

wheel, making the prob- 
lem of extricating the machine from this predicament much more 
difficult. To overcome this disadvantage of the balance gear, it 
is customary to provide a differential lock. One form of this lock 
is illustrated in Fig. 61. On the right-hand side a four-jaw clutch is 
keyed to the drive shaft, but is left free to slide into mesh with its 
corresponding member on the differential housing to permit of lock- 
ing the differential gears. This clutch is operated through a suitable 
linkage from the driver's seat. By locking the differential, the sunken 
wheel will pull itself out if the truck is capable of exerting the 
necessary power. 



245 



66 COMMERCIAL VEHICLES 

Front Drives. Early Development. One of the earliest applica- 
tions of power proposed for road locomotion was the attachment of 
a self-contained power unit to existing horse-drawn vehicles, and a 
number of different types of such units were built in Europe in the 
early days of the industry. For some reason, none of them developed 
to the point of a commercial success. The front-wheel drive, which 
seems to have been discarded almost entirely for some years, has 
recently come to the fore again and has been developed very success- 
fully for fire apparatus, on which both mechanical and electrical 
methods of transmission have been utilized. 



Fig. 60. Jeffery Wheel with Internal Gear Ready for Mounting on Axle 

Electric Front Drive. The electric front drive has been utilized 
in numerous lines of business, more particularly for brewery and 
municipal service, for several years; the Couple-Gear type of electric 
motor wheel, previously described in the section on the transmission 
of power on electric cars, was employed for this purpose. In some 
instances, a single power wheel is used to haul a dump cart or similar 
slow-moving vehicle; or a unit, comprising a storage battery, con- 
troller, steering gear, axle, and two of these power wheels, is per- 
manently coupled to a truck in place of the axle and wheels used 
when drawn by horses. 

Digilized by VjOOQ IC 



COMMERCIAL VEHICLES 67 

The power to drive these motors may be supplied by the current 
from a storage battery or from a gasoline-electric generator. The 



Fig. 61. Bevel-Driven Commercial-Car Axle Fitted with Differential Lock 



Fig. 62. Electric Front Drive Using Couple-Gear Motor Wheels 

dynamo supplies the power directly to the wheel motors through a 
three-point controller, there being no other intermediate electric 



247 



68 COMMERCIAL VEHICLES 

member. This controller is fitted with two forward speeds and a 
single reverse, the speed and amount of power utilized being con- 
trolled chiefly by means of the spark lever and the throttle of the 
gasoline motor in the conventional manner. Fig. 62 illustrates a fire 
engine gasoline-electric tractor using Couple-Gear drive. 

Four-Wheel Drives. To meet the requirements of military 
service, a truck must be able to travel "wherever a team of mules can 
haul a load". Consequently, like that useful quadruped, it must 
be equipped with power-transmitting members at all four points of 
contact with the ground. While the conventional type of truck # 
with one or the other of the standard forms of transmission driving 
only two rear wheels has proved eminently satisfactory for service 
wherever a solid roadbed or its equivalent is to be found, it is of 
little use off the beaten track. Ditches, soft ground, sand, and mud, 
which do not even embarrass the army mule or, for that matter, the 
average team of farm horses, render the average motor truck abso- 
lutely helpless. To be able to extricate itself from bogs and ditches, 
it is necessary to be able to "git up and git" on all fours. 

To take advantage to the full extent of this form of transmission, 
the majority of four-wheel-driven cars both drive and steer through 
all the wheels. Accomplishing this presents no particular mechani- 
cal difficulties. Three forms of drive have been developed for this 
purpose; one in which the power is transmitted through bevel gears 
mounted on the steering knuckle,while a second employs the internal- 
gear type of drive using universal joints on the driving shafts just 
back of the wheels. The third type drives directly to the hubs 
of the wheels through hollow steering knuckles. This last type 
presents the simplest layout and was one of the first to be developed 
in this country on a commercial scale, having been built for several 
years by the Four Wheel Drive Automobile Company. , 

This transmission is a simple modification of the three-speed 
individual-clutch type transmitting the power through a broad silent 
chain to a parallel shaft placed at the left to clear the engine. This 
can be seen more clearly in the photograph of the chassis, Fig. 63. 
This chain also serves as the first reduction in the speed, the second 
being through the conventional form of bevel gears at the rear and 
front axles. Each of these bevel-gear drives incorporates a differ- 
ential for balancing the tractive effort at the wheels, while a third 

Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 69 

differential centrally placed on the parallel driving shaft balances the 
amount of power transmitted to each pair of wheels. This third 
differential is built in the large sprocket of the silent-chain drive and 
is provided with a locking device controlled by the driver. A brake 



Fig. 63. Chassis of Four-Wheel Drive Truck 



drum is mounted on the parallel shaft on either side of the main 
differential. These transmission brakes are for regular service, the 
emergency brakes being mounted in drums on the rear w T heels. 



Fig. 64. Chassis of Jeffery "Quad", Showing Four-Wheel Drive 

Owing to their location, the former retard all four wheels simul- 
taneously. There are, of course, four universal joints. Steering is 
accomplished by means of the front wheels only, so that the rear 
axle is of the conventional full-floating construction. 



,Goo 9 Ie 



Digitized by VjOOQI 



70 



COMMERCIAL VEHICLES 



Jeffery "Quad". This truck is representative of the second 
class, or internal gear-driven type mentioned, and has been devel- 
oped particularly to meet the United States Army requirements. 
The motor is a four-cylinder block-£ast type with L-head cylinders 
rated at 32 horsepower and is fitted with duplex ignition, i.e., using 



Spur Pinion 




Sectional View of Jeffery Front- Wheel Drive 
Courtesy of Horseless Age 

two sets of spark plugs simultaneously. The motor is offset to the 
right side of the frame and mounted on a three-point suspension, 
as shown by the plan view of the chassis, Fig. 64. The drive is 
by shaft to a centrally placed four-speed selectively operated gearset 
of the sliding-gear type, but the latter differs from the conventional 



250 



Digitized by 



Google 



COMMERCIAL VEHICLES 71 

form of this type of gearset in that it has no direct drive. The pro- 
peller shafts are gear driven from the layshaft of the transmission, 
this construction bringing the forward one sufficiently to one side to 
clear the motor. Three differentials are employed, one on each axle 
and one in the gear box, all being of the Wayne gearless type. Both 
axles are "dead" and are fitted with steering knuckles. The trans- 
verse driving shafts at either end are placed above the axles and 
springs and have universal joints just inside of the wheels and directly 
over their steering pivots, as shown by the sectional view, Fig. 65. 
The driving pinion is supported from the steering knuckles between 
two taper roller bearings and drives an internal gear mounted in the 
enlarged wheel hub. Bolted to this large hub and the wheel itself is 



Fig. 66. Chassis of Jeffery "Quad" 

a *pressed-steel drum for an external brake, a dust-excluding felt 
packing being fitted between the drum and the gear ring. The 
ability of the four-wheel drive to extricate itself from heavy mud and 
sand with the same amount of power is due to the tendency of the 
front wheels to climb over obstacles and, at the same time, assist in 
the propulsion of the weight. Enclosed wheels are employed to cut 
down the resistance, Fig. 66. 

J( Electric Transmission 

Advantages. The practice of utilizing electricity for power dis- 
tribution in manufacturing plants was already well established before 
the 'advent of the automobile on a commercial scale, and attempts 
were made at an early day to utilize its advantages for transmitting 



251 Digitized by G00gle 



72 



COMMERCIAL VEHICLES 



the power on the latter. Despite the numerous difficulties met with 
at the outset in the application of the sliding-gear transmission, the 
employment of electricity has never become as general as its advan- 
tages would appear to warrant. A great amount of experimental work, 
however, has been done, and numerous different systems evolved. 
Probably the only example of the consistent employment of electric 
transmission at the present date is to be found in its use on gasoline- 
electric-railway motor cars, of which quite a number are in service. 
As the limitation of weight, one of the most important factors to be 
considered on the automobile, is lacking in this application, it can 

hardly be said to represent an 
cxnct parallel. 

One of the chief advan- 
tages of the employment of 
electric transmission is the 
possibility of running the 
gasoline motor constantly at 
its normal speed, at which it 
develops its rated output 
most economically and with a 
minimum wear. The sharp 
contrast between the speed 
variations required of the gas- 
oline motor employed with a 
mechanical transmission and 
with one of the electrical type 
is shown by the curves in 
Fig. 67. With the electric transmission, the gasoline motor speed 
remains constant from the time of starting right up to 50 miles 
an hour. 

Several Systems. To those familar with electric practice it 
will be plain that several methods of utilizing electricity for the 
transmission of the power on an automobile are available. In general, 
however, they may be divided roughly into three divisions. The 
first of these is simply a replica of that commonly. employed in manu- 
facturing plants, i.e., mechanical energy as produced by an engine 
is converted into electrical power, transmitted to an electric motor 
at a distance, and there reconverted into mechanical energy. This 




eo so 

Miles per Hour 

Fig. 67. Curves Showing Variations of Engine 
Speed for Gasoline-Electric Transmission 



252 



Digitized by 



Google 



COMMERCIAL VEHICLES 73 

double conversion naturally entails a loss of efficiency; but, in manu- 
facturing practice, this is considerably less than where the power is 
directly transmitted from the engine to the tool at which it is to be 
used, and the efficiency increases with an increase in the distance 
between the two. 

The second system involves the conversion of mechanical into 
chemical energy in the storage battery, from which the current is 
drawn to operate electric motors in the usual way, Fig. 68. This is 
really a self-contained electric in that it carries its own charging plant, 
with the further advantage, however, that the excess capacity of the 
generator is always available for driving the vehicle. Or, to put it 



Fig. 68. Couple-Gear Gasoline-Electric System 

the other way around, the greater part of the current from the gasoline 
motor electric-generator unit is employed for running the car, and 
the excess current utilized for charging the storage battery, which 
is then said to be "floated on the line." 

The third system is based on the principle employed in the cradle 
type of electric dynamometer, in which an electric generator is so 
mounted that its field may revolve ia response to the drag exerted 
on it by the armature, this tendency being counteracted by a balance 
lever attached to the field. By means of weights placed on this 
lever, the effort exerted may be accurately weighed, and the power 
developed by the prime mover driving the generator may be calcu- 
lated within close limits. 



Digitized by VjOOQ IC 



74 



COMMERCIAL VEHICLES 



DETAILS OF CHASSIS AND RUNNINQ QEAR 
Springs 
The problem of providing a form of spring suspension that will 
not be overstiff when the car is empty and still provide sufficient hold- 
ing powers to withstand rough road work with a full load, which the 
designer of the touring car has had to face, is aggravated a hundred- 
fold on heavy trucks. Between the "load" and "no load" points 
of the pleasure car, there is a comparatively small range. When a 
touring car weighing 4000 pounds, all on, has its full load of seven 
passengers averaging 150 pounds each, their combined weight 
represents only 25 per cent of the weight of the vehicle itself, but 
when a 5-ton truck, weighing slightly over five tons when empty — say 
11,000 pounds — receives its full load of five tons plus anywhere from 
10,000 to 14,000 pounds, the increase, instead of being from to 25 

per cent, is from to 100 
lllilililifr per cent plus. There is 
also the far greater tend- 
ency to side sway, owing 
to the height at which 
the load is ordinarily 
carried. 

Semi-Elliptic Usual 
Type. As it permits 
keeping the center of 
gravity down, gives less recoil under heavy shock, and is less subject 
to lateral stresses, the flat semi-elliptic type of spring is almost 
universally employed on commercial vehicles, from a delivery wagon 
up to a 7-ton truck. By delivery wagon in this connection is meant 
the type specially designed for commercial service and not the con- 
verted touring-car type in which pleasure-car standards remain 
unaltered, and the high three-quarter elliptic spring at the rear 
is not uncommon. 

It will be apparent, however, that no form of spring suspension 
would be sufficient in itself to cover such an extended range of loading 
as that mentioned and still give even a fair approximation to efficiency 
at either extreme. Maximum carrying ability is the chief thing to 
be provided, and using springs that will do this alone would be an 
easy matter; but the problem is to guard against the maximum 



lMM*M4Jiiy 




^*T**^^ B ^ B ^^^^ fi ^ a *^^n 


AmM£3 


U >fr >« * ^ *• * ^B^ 



Fig. 69. Principle of the Compensating Spring 
Support Employed on Heavy Trucks ' 



254 



Digitized by 



Google 



COMMERCIAL VEHICLES 75 

stresses to which the springs will be subjected under heavy loads and 
still have a suspension that will prevent the motor and driving 
mechanism of the truck from being pounded to pieces when the 
vehicle is running without a load. To achieve this, it is customary to 
employ rocking shackles at one end and some form of sliding, or com- 
pensating, support at the other, although in numerous instances the 
springs are shackled at both ends in the same manner. As the driving 
strain is practically always taken on radius, or distance, rods in the 
case of side-chain-driven cars, and on torque rods on cars of the shaft- 
driven type, there is ample altitude for variation in this respect. 

Principle of Compensating Support. The sketch, Fig. 69, illus- 
trates the principle upon which all compensating supports for the 
springs is based. Of course, this applies only to the rear-wheel springs, 
which are usually called upon to bear anywhere from 60 to 85 per 
cent of the useful load. The front springs are usually pinned to 
the dropped dumb ends of the frame forward and shackled to brackets 
at their rear ends. The front end of a rear spring is shown by the 
illustration. Given a suspension sufficiently stiff to withstand the 
maximum load of which the truck is capable, it will be apparent 
that when empty the body will be lifted and the sliding end of the 
spring will be against the right-hand end of the support. The spring 
is then under its minimum compression and will respond more readily 
to shock. 

Brakes 

Usual Types. In as much as the greater loads carried far more 
than offset the lower speeds at which commercial cars travel as com- 
pared with the pleasure type, there can be no comparison of the 
braking requirements of the two. This is particularly the case in as 
much as the greatest strain does not come on the brakes because of 
the infrequent necessity for stopping suddenly but on account of 
their continued use in holding the loaded truck back on long hills. 
Commercial-car brake design naturally varies with the type of vehicle 
and likewise with its carrying capacity. On light delivery wagons, 
the type employed is the same as used on touring cars, viz, internal- 
expanding and external-contracting asbestos-fabric-lined shoes in 
pressed-steel drums on the rear wheels. In some instances, the 
practice, usually confined to the higher-priced pleasure cars, of placing 
the two sets of brak^" " ; de by side so that they contact on the same 

2 " 5 Digitized by G00gle 



76 COMMERCIAL VEHICLES 

drum and can be enclosed against the entry of dirt and water, is also 
found. An example of the first type mentioned is shown in Fig. 70, 
which illustrates a Timken worm-driven rear axle. The brakes on 
the Reo chassis are shown in Fig. 71. 

Braking AH Wheels. Considerable discussion has arisen from 
time to time regarding the advisability of braking on all four wheels; 



Fig. 70. Timken Worm-Driven Rear'Axle, Showing Brakes 

but, prior to the advent of the four-wheel drive, this was tried in only 
a comparatively few instances. In addition to providing greater 
retarding power, the advantage of eliminating the tendency to skid 
has also been attributed to the front-wheel brake. When all four 



Fig. 71. Brake Detail, Reo 2-Ton Chassis 

wheels are driven, brakes are applied to all simultaneously, the brak- 
ing effort at each wheel being equalized by a compensating device. 
On the Jeffery "Quad", these brakes are applied directly to the 
wheels themselves and consist of a simple and well-worked-out 
internal-expanding cam-actuated type, as shown by Fig. 72. 



256 litizedbyC 



COMMERCIAL VEHICLES 



77 



TRAILERS 
Utilizing Excess Power. Trucks, like all other motor vehicles, 
must necessarily be equipped with power plants capable of success- 
fully meeting exceptionally severe conditions imposed by heavy 
grades and by muddy, sandy, and snowy road surfaces, as well as 
the normally easy grade and road conditions encountered by the 
average truck during a very large proportion of its service. Hence, 
there is a large reserve power-plant capacity idle for a great part of 
the time. From the economic standpoint, it is a wasteful condition 
for a truck with sufficient power to handle a ten-ton load on smooth 




Fig. 72. Internal Expanding Cam-Actuated Type of Brake 
Employed on the Jeffery "Quad" 

level roads to be restricted to the five-ton load which its structural 
parts permit. This applies proportionately to all sizes of commercial 
vehicles, from the very lightest up, and it accounts for the widespread 
use to which trailers are being put. 

Two-Wheel Types. For light- and medium-capacity service, 
trailers can be made with only two wheels, thus keeping the wheel- 
Tmse of the double unit down and permitting of much higher speeds. 
Trailers designed for use in connection with the lightest types of 
delivery wagons, such as the Ford, or for the thousands of ex-touring 
cars that are spending the second period of their existence in a com- 
mercial r&le, usually carry a load of about 400 pounds. They are 



257 



Digitized by 



Google 



78 COMMERCIAL VEHICLES 

made to fit any standard make of automobile, a special bracket 
being fitted to the rear of the frame of the car. Connection is made 
by means of a tongue fitted with a swiveling pin and locked with a 
thumb nut, so that the trailer may be attached or detached quickly 
without using tools; the pin in question, together with the fact that 
the trailer has only a single axle, allows for universal relative move- 
ment between it and the towing car. 

Four-Wheel Types. It is in the employment of what is prac- 
tically a second truck, where its carrying capacity is concerned, that 
the use of the trailer shows the greatest operating economy, and 



Fig. 73. Troy Trailer for Motor Trucks 

specially designed vehicles have been developed for this purpose. 
The builders of the Troy wagons have evolved a special type of 
trailer for the motor truck, as shown in Fig. 73. 

Troy Trailer, It will be noted upon referring to the illustra- 
tion, Fig. 73, previously mentioned, that the construction of the 
Troy trailer is along very similar lines to those generally followed in 
motor-truck construction. In fact, the trailer is practically a motor 
truck without power and, as if is subjected to even heavier loading 
and more severe strains than the latter, is built accordingly. 

Both sets of wheels are designed to steer and are controlled by 
the drawbars at each' end of the trailer, the cross-connecting rod of 

Digitized by VjOOQ IC 



COMMERCIAL VEHICLES 79 

the steering gear being attached to the under side of the drawbar 
near its rear end. As the drawbar follows its towing truck around 
corners, it also serves to swerve the front wheels of the trailer in the 
same direction. 



259 



Digitized by VjOOQIC 



ELECTRIC AUTOMOBILES 

PART I 



Introduction. The essentials of the electric automobile are 
few in number and simple in construction. They are, first, the 
storage battery, or source of power; second, the electric motor, 
forming the medium through which the current is transformed 
into mechanical energy; and, third, the drive, or means by which 
the power of the motor is in turn applied to the propulsion of the 
vehicle. There are, naturally, differences in design and in the 
details by which the power produced at the electrical end is 
applied to driving the machine. Where these differences are of 
sufficient importance, they are described in detail, and illustra- 
tions of the vehicles and their component parts are given, thus 
making it easy to distinguish them. 

FUNDAMENTAL FEATURES OF THE ELECTRIC 
THE STORAGE BATTERY 

There is probably no other single electrical device in general 
use about which there is so much popular misconception as the 
storage battery, or accumulator, as it is more technically known. 
It does not in itself create a current of electricity — as does a primary 
battery, such as the familiar dry cell, in which chemical processes 
actually generate a current of electricity — and for this reason the 
storage cell is called a secondary battery. The word storage in con- 
nection with this type is really a misnomer, as the process by which 
it absorbs and re-delivers electricity is not one of storage in any sense 
of the word, but consists of chemical conversion and reconversion 
upon a reversal of the conditions. As is the case with, electric 
vehicles, there are numerous different forms of storage batteries, for 
many of which special advantages are claimed; but in general all 
lead-plate batteries are very much alike, and a description of one 
will make clear the principles upon whicn all are based. Theoreti- 
cally, the principle of the Edison battery is also the same, i.e., that 
of a chemical reaction upon the passage of the charging current 



261 ' ,Goo 9 Ie 



Digitized by VjOOQI 



2 ELECTRIC AUTOMOBILES 

through the cell and a reconversion upon a reversal of the condi- 
tions, but it differs so radically in practice that a detailed descrip- 
tion of its construction is given. 

CONSTRUCTION AND ACTION OF TYPICAL CELL 

General Description. 'In order to obtain an understanding of 
just how these processes are carried on, it is necessary to become 
familiar with the internal action of the cell oh receiving and dis- 
charging a current and, for this purpose, it is essential to delve into 
chemistry somewhat. Before taking up this subject, it may be well 
to mention that a battery is composed of a group of cells, each of which 



Fig. 1. Typical Battery Plates 

is a complete and self-contained unit, though the term battery is 
indiscriminately applied to both. In a description of its working, a 
cell is naturally referred to, as all are alike. A cell consists of two 
sets of lead grids tvith pockets so cast in them that what is known as the 
"active material" may be securely held even in case of severe jolting and 
vibration. When filled with the active material, these grids are called 
plates and are divided into two groups, one positive or + (plus) in 
character, and the other negative or — (minus), of which typical 
illustrations are given in Fig. 1. As it is necessary, in order to obtain 
maximum efficiency, to oppose a surface of negative capacity to each 
surface of a positive nature, every storage cell will be found to have 
one more negative than positive plate. It is possible to distinguish 
them in this manner, where other indications are lacking, but as it is 

262 



ELECTRIC AUTOMOBILES 3 

most essential that they be known, the terminals or connections of the 
groups are plainly marked by the makers either by the plus and minus 
signs or in some other equally plain manner, such as painting the 
positive terminal red. These groups of plates are known as electrodes 
and are inserted in a jar containing a solution termed the electrolyte, 
which consists of water and sulphuric acid. Fig. 2 shows a sec- 
tional view of a small cell. 

Electrolyte. The solution in which the elements of the storage 
battery are immersed, or electrolyte, as it is termed, consists of 

pure sulphuric acid and distilled, 
or other pure, water. Concen- 
trated sulphuric acid is a heavy oily 
liquid having a specific gravity of 
about 1.835. A battery will not 
operate if the acid is too strong, 
and it is therefore diluted with suf- 
ficient water to bring it about 1 .275 
for a fully charged cell. While a 
battery is being discharged, the elec- 
trolyte becomes weaker as part of 
the acid is combined in the plates 
in producing the current. This 
weakening of the electrolyte causes 
the specific gravity to drop 100 to 
150 points during the complete 
Kg. 2. Assembled storage Cell discharge. During the charge, this 

acid is returned to the electrolyte, 
thus increasing its strength until it again reaches the normal 
gravity. There being no loss of acid, it is never necessary during 
the normal service of a battery to add any acid to the cells. 

Unless acid is actually known to have been lost out of a cell, none 
should ever be added during the entire life of the battery. 

When the cells have been allowed to gas too freely, for reasons 
that are explained later, there is more or less spray of acid through the 
vent holes, but the amount of acid lost in this way is so small as to be 
entirely negligible. The gravity of the electrolyte need not neces- 
sarily be exact, as in a fully charged battery a range of from 1.250 to 
1.300 is permissible. 



263 Digitized by G00gk 



4 ELECTRIC AUTOMOBILES 

Purity of Acid and Water. Both the acid and the water used in 
making electrolyte should be chemically pure to a certain standard. 
This is the same standard of purity in acid as is usually sold in drug 
stores as "C P" (chemically pure), or by the chemical manufacturers 
as "battery acid". In this connection, the expression "chemically 
pure" acid is sometimes confused with acid of full strength, approxi- 
mately 1.835 sp.gr., and at the same time chemically pure. If this 
chemically pure acid of full strength be mixed with distilled water, the 
mixture will still be chemically pure but not of full strength. On the 
other hand, if a small quantity of some impurity be introduced into 
the acid, it would not materially reduce the strength, but the acid 
would no longer be chemically pure. 

Determination of Strength of Acid. The usual method of deter- 
mining the strength of electrolyte is by taking its specific gravity, 
this method being possible because of the fact that sulphuric acid is 
heavier than water. Therefore, the greater the proportion of acid 
contained in the electrolyte, the heavier the solution or the higher 
its gravity. By specific gravity is meant the relative weight of any 
substance compared with distilled water as a basis. Pure water, 
therefore, is considered to have a gravity of 1. An equal volume of 
chemically pure sulphuric acid weighs 1.835 pounds. It, therefore, 
has a specific gravity of 1.835 and is referred to as "eighteen thirty- 
five , \ As it is customary to carry the gravity readings out to three 
decimal places, the gravity of water, which is 1, is written 1.000 and is 
spoken of as "one thousand". These specific gravity readings are 
usually taken by means of a hydrometer, shown in Fig. 3, and dis- 
cussed on page 8. 

Temperature Correction. Since the electrolyte, like other sub- 
stances, expands when heated, its specific gravity is affected by a 
change in temperature. If electrolyte has a certain specific gravity 
at 70° F. and is then heated, the heat will cause the electrolyte to 
expand, and although the actual strength of the solution will be the 
same as before heating, yet the expansion will cause it to have a lower 
specific gravity, the difference amounting to approximately one point 
(.001) for each three degrees rise in temperature. For instance, if 
electrolyte has a reading of 1.270 at 70° F. and the temperature be 
raised to 73° F., this increase in temperature will expand the electrolyte 
sufficiently to drop its gravity from 1.275 to 1.274. On the other 

264 



ELECTRIC AUTOMOBILES 



TABLE I 
Sulphuric-Acid Solutions 41 

on one part acid of 1.835 sp. gr. at 60° F. 



Specific Gravity of 
Solution (70" F.) 


Pabtb of Water to One Pabt Acid 


Percentage of 

Sulphuric Acid 

in Solution 


By Volume 


By Weight 


1.100 


9.8 


5.4 


14.65 


1.110 


8.8 


4.84 


16. 


1.120 


8. 


4.4 


17.4 


1.130 


7.28 


3.98 


18.8 


1.140 


6.68 


3.63 


20.1 


1.160 


6.15 


3.35 


21.4 


1.160 


5.7 


3.11 


22.7 


1.170 


5.3 


2.9 


24. 


1.180 


4.95 


2.7 


25.2 


1.190 


4.62 


2.52 


26.5 


1.200 


4.33 


2.36 


27.7 


1.210 


4.07 


2.22 


29. 


1.220 


3.84 


2.09 


30.2 


1.230 


3.6 


1.97 


31.4 


1.240 


3.4 


1.86 


32.5 


1.260 


3.22 


1.76 


33.7 


1.260 


3.05 


1.66 


35. 


1.270 


2.9 


1.57 


36.1 


1.280 


2.75 


1.49 


37.3 


1.290 


2.6 


1.41 


38.5 


1.300 


2.47 


1.34 


39.65 


1.320 


2.24 


1.22 


42. 


1.340 


2.04 


1.11 


44.1 


1.360 


1.86 


1.01 


46.3 


1.380 


1.7 


.92 


48.4 


1.400 


1.56 


.84 


50.5 


1.460 


1.25 


.68 


55.5 


1.500 


1. 


.55 


60.15 


1.650 


.8 


.44 


64.6 


1.600 


.639 


.348 


69.12 


1.650 


.497 


.27 


73.32 


1.700 


.369 


.201 


77.6 


1.750 


.248 


.135 


82.1 


1.800 


.1192 


.0646 


87.5 


1.835 


0. 


0. 


93.19 



* Courtesy of Electric Storage Battery Co. 



hand, if the temperature had dropped to 67° F., this would have 
caused the gravity of the electrolyte to rise to 1 .276. Since change of 



265 



Digitized by 



Google 



6 ELECTRIC AUTOMOBILES 

temperature does not alter the strength of the electrolyte but merely 
changes its specific gravity, the gravity reading should be corrected 
one point for every three degrees change in temperature. For con- 
venience, 70° F. is considered normal and is the point from which 
corrections are made. This refers to the temperature of the electro- 
lyte itself and not to that of the surrounding air. Table I shows the 
parts of water by volume, the parts of water by weight, and the per- 
centage of acid to water to produce different specific gravities. 

Replacing Evaporation or Other Losses. The electrolyte, or solu- 
tion, in the cell consists of a mixture of sulphuric acid and water; the 
sulphuric acid does not evaporate, but the water does. When the level 
of the electrolyte becomes low, it is due under normal conditions to the 
evaporation of water, and this loss should be replaced with water only. 
There being no loss of acid, it is never necessary during normal service 
to add any acid to a battery. Of course, if a jar is upset and acid 
spilled, or if a jar breaks and the acid leaks out, it must be replaced. 
Care should be taken to see that the cells do not become flooded with 
water when washing the car; this is apt to short-circuit them across 
the lead connectors and if it enters the cells to disturb the specific 
gravity of the electrolyte. 

Unless acid is actually known to be lost out of a cell, none should 
ever be added during the entire life of a battery. The amount of acid 
lost in the form of spray due to the gassing of the cells is so small that 
it may be neglected. Only distilled water or other water of approved 
purity should be used for replacing evaporation. Most natural waters 
contain impurities, some of which are chemically injurious to the 
batteries, while others are not. Any water to be regularly used in a 
garage for battery purposes without distillation should be submitted 
to the battery manufacturer for approval. 

It is necessary that the plates and separators be covered with 
electrolyte at all times. When adding water, cover the plates about 
$ inch. Do not put in more than this amount on the theory that if a 
little is good more is better, since cells that are over-full tend to slop 
while the car is running and will also be apt to lose electrolyte while 
charging, as gassing raises the level of the solution in the cells. 
Replace evaporation every five to fifteen days, depending upon the 
conditions of service. The best time for adding water is just before a 
charge. This may be done most conveniently with th~ aid of a 

266 Digitized by-GoOgk 



ELECTRIC AUTOMOBILES 7 

syringe of the type ordinarily used with a hydrometer. Keeping 
the cells filled to the proper level with electrolyte is quite as important 
as not allowing them to stand discharged for any length of time. 

Adjusting the Specific Gravity. The best indication of the condi- 
tion of a storage cell at any time is the specific gravity of its electrolyte 
and the treatment to be given should always be governed by the latter. 
The electrolyte of a fully charged cell of the vehicle type when first 
put into service should have a specific gravity of 1.270 to 1.280. 
Although this will change somewhat with age, the battery will con- 
tinue to give good service between the limits of 1.250 and 1.300. If 
the gravity should ever rise above 1 .300, it should be lowered promptly 
by replacing some of the electrolyte with pure water. Low gravity 
in a cell is usually caused by acid being combined in the plates through 
lack of charge; although, if a jar has been upset and acid spilled, or 
the jar is leaking, no amount of charging will bring its specific gravity 
up to the proper point. A decreasing specific gravity in the electro- 
lyte throughout the cells of an entire battery is an indication that 
sediment is accumulating in the bottom of the jars and that the 
battery requires washing. This is true, of course, only when the low 
reading is not due to insufficient charging. 

Before attempting to raise the specific gravity of any cell by 
adding acid, charge the battery until certain that a maximum gravity 
has been reached or, in other words, that no acid is still combined 
with the plates in the cell. For example, if the electrolyte in a cell 
should be adjusted to 1.275 when 50 points of acid still remain in the 
plates, the gravity would rise to 1.325 if the cell were subsequently 
charged to its maximum. 

To adjust the specific gravity to its proper value (1.270 to 1.280), 
first bring the battery to its true maximum, which can be assured only 
by charging until there is no further rise in gravity during a period of 
at least twenty-four hours of continuous charging at about one-half 
the normal finishing rate. If, after this, the specific gravity is too 
high, remove electrolyte down to the level of the plates with the 
syringe and replace with pure water to J inch over the plates; if 
the specific gravity is too low, replace with 1.300 electrolyte, adding it 
in small quantities to prevent bringing about the opposite condition. 

When much adjustment is necessary and facilities are available, 
as should be the case in a garage handling many electric vehicles, 

267 

Digitized by VjOOQ IC 



8 



ELECTRIC AUTOMOBILES 



it is good practice to pour the electrolyte out of the cells into a glazed 
earthenware vessel or a lead-lined tank, and to raise or lower the specific 
gravity of this electrolyte as conditions demand. About one-third 
of the electrolyte is held in the plates and the separators and cannot 
be poured out, and this 



r— i 

1 



i 



M 



£ 



if 








I 
I 

i 

K 



£ 



a 



S 



* 



£ 



m 



m 



± M 



r 



i 



it 



should be allowed for in 
estimating the proper 
gravity before refilling 
the cells. In cases where 
there is a wide variation 
between different cells, 
further adjustment may 
be necessary. 

Hydrometer and Its 
Use. The specific gravity 
of a liquid is tested by 
means of an instrument, 
termed a hydrometer, con- 
sisting of a weighted 
gl&ss tube having an 
appropriate scale. The 
depth to which this 
instrument sinks in the 
liquid to be tested shows 
its specific gravity by the 
reading of the scale at 
the level of the liquid. 
Fig. 3 shows the several 
types of hydrometers, 
while beside each is an 
enlarged view of the 
scale. The Type V-l is 
more commonly used 
with electric vehicle bat- 
teries, and Type S-l with 
starting and lighting bat- 
teries. Type M is employed in the battery rooms of central stations 
where more exact readings are required. 



m 



i 



i 



/ 



f 



v-l 

Hydrom«t«r 



TYrr 
S-l 



\ 



TYpc 

M 

[frdrometer 



Fig. 3. 



w 



\ 



Types of Hydrometers for Determining 
Specific Gravity 



268 



Digitized by 



Google' 



ELECTRIC AUTOMOBILES 

Where only occasional readings are taken a testing set, such as 
that shown in Fig. 54, Part II, will serve all purposes, the acid being 
transferred from the cell to the glass tube by means of the syringe, 
putting in just sufficient to float the hydrometer clear of the bottom. 
For constant use in connection with either vehicle or starting and 
lighting batteries, the type shown in Fig. 53, Part II, is most practical. 
The readings may be made more rapidly, and there is no danger of 
spilling acid on the tops of the cells or on the hands. To prevent the 
hydrometer from sticking to the sides of the barrel, it is necessary 
to hold it vertically to take the reading. As some of the cells on cer- 
tain makes of cars are not so situated that the test can be made in 
this way, the soft-rubber plug in the bottom of the glass barrel is in the 
form of a trap so that when sufficient acid has been drawn into the 
barrel, the hydrometer nozzle can be removed from the vent hole 
of the cell and held in a vertical position, and the acid will not 
run out. The acid should be immediately returned to the same cell. 

Failure to replace the acid withdrawn for a test in the same cell 
from which it was taken is apt to cause trouble. For example, if acid 
is taken from one cell, and, after making the reading, it is replaced 
in another cell, the result is that the amount of acid taken from the 
first cell is later replaced with water, making the electrolyte that 
much weaker, and vice versa. As soon as sufficient electrolyte has 
been drawn into the barrel, care being taken to see that the instru- 
ment is not sticking to the sides of the latter, note underneath the 
level of the liquid the graduation on the stem of the hydrometer. 

For the convenience of the tester, a thermometer has been 
designed with a special scale opposite the mercury column. This 
scale corresponds to the temperature scale and indicates at a glance 
the correction required for the temperature reading. See Fig. 4. 
Opposite 70° it will be noted that the scale reads zero; above this the 
correction is plus and below it minus. In making readings, however, 
it is not customary to note a temperature correction for each, but 
simply to record the temperature at which the tests are made, 
and if the variation is sufficient to make the correction important, 
this is done after all have been taken. The necessary temperature 
corrections for the specific gravity are given from 30° to 100° F. 
in Table III, Part II, but in this case the rated specific gravity for 
various stages of charge is based. on*a_temperature of 80° F. 

- Digitized by VjOOQ'IC 



10 ELECTRIC AUTOMOBILES 

A hydrometer test, however, cannot always be considered as 
conclusive evidence of the condition of a cell. The hydrometer 
alone may sometimes be a very unreliable guide as to the charged or 
discharged condition of a cell. For example, if electrolyte or acid 
had just previously been added to the cell without the knowledge of 
the tester, the hydrometer rea'ding would apparently show the battery 
to be fully charged when the reverse might be the case. Conse- 
quently, voltage tests must be used in addition as, in the instance just 
cited, the voltmeter would give an indication directly opposite to that 
of the hydrometer. Under average conditions, however, the hydrom- 
eter alone will closely indicate the state of charge, though it is not 
to be relied upon in all cases. When there is not enough electrolyte 
in the cell to make it possible to use the hydrometer for a test, add 
enough distilled water to restore the normal level and then charge 
for at least one hour before making the test, as, when recently added, 
the water will remain at the top of the cell, and the reading thus taken 
will be valueless. Charging the battery mixes the water thoroughly 
with the acid of the electrolyte. 

Specific gravity readings between 1.275 and 1.300 indicate that 
the battery is fully charged; between 1.200 and 1.225 that the battery 
is more than half discharged ; between 1 . 1 50 and 1 .200 that the battery 
is nearing a fully discharged condition and must be recharged very 
shortly, as otherwise serious damage will result; below 1.150 that the 
battery is exhausted and must be recharged immediately. 

Variations in Readings. Where the specific gravity in any cell 
tests more than 25 points lower than the average of the others in 
the battery, it is an indication that this cell is out of order. Depend- 
ence should not be placed, however, on a single reading where there 
is any question as to the specific gravity. Take several readings and 
average them. Variations in cell readings may be due to short- 
circuits inside the cell; putting too much water in the cell, causing 
loss of electrolyte through overflowing; or to loss of electrolyte caused 
by a cracked, or leaky, jar. Short-circuits may result from a broken 
separator or from an accumulation of sediment in the bottom of the 
jar reaching the plates. 

When first testing the cells, low specific gravity in one or more of 
them may often be equalized by charging, during which frequent 
readings should be taken at short intervals. If the specific gravity 

Digitized by VjOOQ lC 



ELECTRIC AUTOMOBILES 11 

in any of the cells does not rise to 1.260 after the other cell readings 
indicate that the battery is fully charged, it is an indication that the 
low cell is in need of internal adjustment, and it must be dismantled 
in accordance with the instructions given under that head. See also 
instructions under "Renewal of an Element" for the method of 
remedying the trouble. 

Quite a substantial percentage of battery troubles — and this is 
particularly the case with starting-system batteries that are usually 
neglected until they give out — may be traced to letting the electrolyte 
get too low in the jars. The effect of this is to weaken the battery, 
thus causing it to discharge more readily and frequently resulting in 
harmful sulphating of the plates and injury to the separators. When 
the latter occurs, it permits the plates to come into contact and causes 
an internal short-circuit. The importance of always maintaining 
the level of the electrolyte % inch above the tops of the plates by fre- 
quent addition of distilled water to bring it up will be evident from 
this. If, after the occurrence of low cells, the battery does not 
regain its full efficiency after one or two days, it is an indication that 
sulphating has taken place, and the remedy as given under that 
heading should be applied without delay, as letting a battery go 
without attention in this condition will ruin it. 

One of the most frequent causes for low electrolyte in a cell is the 
presence of a cracked, or leaky, jar, and if one of the cells requires more 
frequent addition of water to maintain the level of its electrolyte, it is 
an indication that it is leaking. Unless the jar is replaced imme- 
diately, the cell itself will be ruined, and it may cause serious damage 
to the remainder of the battery. Jars are often broken, owing to the 
hold-downs becoming loose and allowing the battery to jolt around, or 
it may be due to freezing. The presence of a frozen cell in a battery 
shows that it has been allowed to stand in an undercharged condition 
in cold weather, as a fully charged cell will not freeze except at very 
low temperatures. 

Frozen Cells. In some cases the cells may freeze without crack- 
ing the jars. This will be indicated by a great falling off in the effi- 
ciency of the cells that have suffered this injury or by a totally dis- 
charged condition, which cannot be remedied by continuous charging. 
In other words, the battery is "dead", and the plates are worthless 
except as scrap lead. In all cases where cells have been frozen, 



271 



12 ELECTRIC AUTOMOBILES 

whether the jar has cracked or not, the plates must be replaced at 
once. It must always be borne in mind that low temperatures 
seriously affect the efficiency of the storage battery and this should 
be taken into consideration when making hydrometer tests in cold 
weather. The readings will not be the same in winter as they are 
in summer for the same condition of charge. 

Process of Charging. Precautions Regarding Electrolyte. To 
charge, direct current is passed through the cells in the direction 
opposite to that of discharge. This current passing through the 
cells in the reverse direction reverses the chemical action which 
took place in the cells during the discharge. During the latter the 
acid of the electrolyte penetrates the active material and com- 
bines with it, filling its pores with lead sulphate and causing the 
electrolyte to become weaker. Reversing the current through this 
sulphate in the plates restores the active material to its original 
condition and returns the acid to the electrolyte. This is why the 
battery manufacturer lays such stress on his instructions never to 
add acid to the electrolyte to bring up the specific gravity. Low grav- 
ity indicates that a large proportion of the acid is combined with 
the active material of the plates, and that when the cells are 
recharged this acid will be returned to the electrolyte; thus any 
addition will represent an excess. 

During the charge the electrolyte gradually becomes stronger, 
as the sulphate in the plates decreases until no more sulphate 
remains and all the acid has been returned to the electrolyte, 
when it will be of the same strength as before the discharge, and 
the same acid will be ready to be used over again in the next dis- 
charge. Since there is no loss of acid, none should ever be added 
to the electrolyte. The acid absorbed by the plates during the 
discharge is driven from the plates by the charging current and 
restored to the electrolyte during the charge. This is the whole 
object of charging. 

Charging Rati and Time of Charge. In charging there are 
only two factors to be considered, rate in amperes, and time. The 
rate in amperes is limited by the state of discharge. When the 
cells are fully discharged, in which condition the plates contain 
the maximum amount of sulphate, the charging current can be 
utilized at the highest rate. 

272 



ELECTRIC AUTOMOBILES 13 

Gassing. As the charge progresses and the amount of sulphate 
in the plates decreases, they can no longer absorb current at the same 
rate, and the charge must be reduced. This becomes necessary when 
the cells begin to give off hydrogen gas. This is termed gassing and is 
an important feature of the process of recharging, since gassing shows 
at any time whether or not the charging rate is too high. Passing 
current through a cell will always be followed by a reaction in the cell; 
just what this reaction will be depends upon the condition of the cell 
at the time. In any case the current will always follow the path of \ 
least resistance and will accordingly always do the easiest thing first. 
When the cell is in a discharged state, the easiest thing is to decompose 
the lead sulphate. As there is a comparatively large amount of lead 
sulphate in a fully discharged cell, a correspondingly large, amount of 
current can be used in charging. But as the amount of sulphate 
progressively decreases with the charge, a point is reached at which 
there is no longer sufficient sulphate remaining to ultilize all the 
current that is passing through the cell. 

The excess current will then begin to do the next easiest thing, 
which is to decompose the water of the electrolyte and produce gas. 
Therefore, when the cells begin to gas freely, it indicates that current 
is being passed through them at too high a rate, and the charge should 
be reduced sufficiently to stop the gassing. As the charge is continued 
at the lower rate, the remaining sulphate will continue to decrease in 
amount until there is no longer sufficient to utilize the smaller amount 
of current, and the cells will again begin to gas. The charge should 
be reduced each time the gassing begins. When the cells begin to gas 
freely at a very low charging rate, it indicates that there is practically 
no sulphate remaining, so that even this small amount of current 
cannot be utilized, and the charge is complete. 

Discharge. The action of the cell on discharge is briefly as 
follows: When the cell is connected up to discharge, the current is 
produced by the acid in the electrolyte combining with the lead of the 
porous parts of the plates, termed the active material which, as 
already mentioned, consists of lead peroxide in the positive plates and 
metallic lead in a spongy form in the negative plates. When the 
sulphuric acid in the electrolyte combines with the lead in the active 
material, a compound, lead sulphate, is formed. This is formed in 
the same way that sulphuric acid dropped on the copper wiring, or 

273 



14 ELECTRIC AUTOMOBILES 

terminals, forms copper sulphate, or acid dropped on the iron work 
of the car forms iron sulphate. In cases of this kind it will always 
be noted that an amount of sulphate is formed out of all propor- 
tion to the quantity of metal eaten away. In the same manner, 
the sulphuric acid of the electrolyte combines with lead in the 
plates forming lead sulphate which, on account of its increased 
volume, fills the pores of the active material. 

As the discharge progresses, the electrolyte becomes weaker in 
proportion to the amount of acid absorbed by the active material of 
the plates in the formation of lead sulphate, a compound of acid and 
lead. This lead sulphate continues to increase in quantity and bulk, 
filling the pores of the plates, and, as these pores are stopped up by 
the sulphate, the free circulation of the acid through the plates is 
retarded. Since the acid cannot reach the active material in the 
plates fast enough to maintain the normal action, the battery 
becomes less active, as is evidenced by a rapid drop in voltage. 
Experiences show that at the normal discharge rate, the voltage will 
begin to drop very rapidly soon after reaching 1.8 volts per cell. 

During a normal discharge, the amount of acid used from the 
electrolyte will cause the gravity to drop 100 to 150 points. Thus, 
if the gravity of a fully charged cell is 1.275, it will, at the end of 
the discharge, be between 1.175 and 1.125, depending on the type 
of cell. The battery should never be allowed to drop below this 
point, but should immediately be placed on charge. 

Efficiency of Storage Ceil. About 20 per cent of the energy em- 
ployed in charging the cell is lost in the process, so that the efficiency 
of the storage cell in good condition is approximately 80 per cent, 
this representing the available output of the fully charged cell. By 
abuse or neglect this percentage of efficiency may fall so low that the 
figures given will be almost reversed, from which the necessity for 
properly looking after the battery may be appreciated, particularly 
when it is expressed in terms of miles per charge and the reduced capa- 
city may mean stranding at quite a distance from a source of current. 

Sulphating. The conversion of the active material into lead sul- 
phate, which takes place during the discharge of the cells, is a normal 
reaction and as such occasions no damage. If, however, the cells 
are allowed to stand for any length of time in a discharged condi- 
tion, the sulphate not only continues to increase in amount but 

Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 15 

becomes hard and white, and the presence of white spots on the plates 
is an indication that the cells have been neglected. In this condition, 
the plates have lost their porosity to a considerable extent and it is 
correspondingly more difficult to force the charging current through 
the active material. This is the abnormal condition usually referred 
to as svlphated. 

Continued and persistent charging at a low rate will restore prac- 
tically any condition of sulphate, the time necessary being in propor- 
tion to the degree to which the condition has been allowed to extend. 
It is entirely a question of time, since a higher rate will only produce 
gassing and high temperature, the low rate being all that the cells in 
this condition are capable of using. 

Time Necessary to Restore a Svlphated Battery. The additional 
length of time necessary to restore a sulphated battery is illustrated 
by the following test : 

Preventing Svlphating. In ordinary charging, there is usually 
not sufficient time to continue the charge until absolutely all the 
sulphate has been converted. To prevent the small amount of 
sulphate remaining from increasing and getting hard, an equalizing 
charge should be given at frequent intervals. Some makers recom- 
mend doing this once a week, others every fortnight, and still others 
once a month. This equalizing charge is an extra long charge at a 
low rate, whereby no more current than can be absorbed by the 
amount of sulphate remaining is passed through the cells. 

A battery was charged to the maximum, and the gravity regulated to exactly 
1.275, with the electrolyte just one-half inch above the tops of the plates, this 
height being carefully marked. The battery was then discharged and recharged 
to 1.275 at the normal rate in each case. The specific gravity changed from 
1 .265 to 1.275 during the last hour and a half of the charge. During the following 
twelve weeks the battery was charged and discharged daily, each charge being 
only to 1.265, thus leaving 10 points of acid still in the plate. At the end of the 
twelve weeks the charge was continued, to determine the time required to regain 
the 10 points and thus restore the specific gravity to the original 1.275. Eleven 
hours were needed, as compared with the hour and a half needed at first. 

The test further illustrates why it is necessary to give a battery 
an occasional overcharge, or equalizing charge, to prevent it becom- 
ing sulphated. Had the battery in question been charged daily to its 
maximum of 1.275 and discharged to the same extent during the 
twelve weeks, nine and a half hours of the last charge would have been 
saved. It is neither necessary nor desirable, however, to carry every 

275 

Digitized by VjOOQlC 



16 ELECTRIC AUTOMOBILES 

charge to its absolute maximum. The weekly equalizing charge is 
better practice. 

Restoring a Sulphated Battery. It has become more or less 
common to suspect the battery of being sulphated every time it fails 
to give the mileage the user thinks it should give on an electric vehicle, 
or to have the capacity for starting that, in the driver's estimation, it 
should have, on a gasoline car. But if the sediment has not been 
allowed to reach the bottom of the plates, and if the level of the 
electrolyte over the plates has been properly maintained by replacing 
evaporation with distilled water, the battery can be sulphated only 
because it has not been properly charged, or because acid has been 
added to the electrolyte. An individual cell may become sulphated 
through an internal short-circuit, or by drying out as might be caused 
by failure to replace evaporation with water, or failure to properly 
replace a broken jar. 

Sulphate Tests. To determine whether a battery is sulphated 
when it is known that it does not require cleaning, it is advisable to 
remove it from the car, give it the ordinary equalizing charge, and 
discharge it at the normal rate. If it gives its rated capacity, the 
reason for short mileage should be looked for elsewhere in the electric 
vehicle, or in the other essentials of the starting and lighting system 
on a gasoline car. (The removal of the battery refers to an electric 
vehicle and not to a starting arid lighting battery.) If the rated 
capacity is not obtained on this discharge, recharge in the usual way. 
When the battery is considered fully charged, take and record a 
hydrometer reading of each cell and the temperature of one cell. 
Charge the battery at a rate as near one-half its normal rate as the 
charging apparatus will permit. If the temperature reaches 100° F., 
reduce the current or temporarily interrupt the charge not to exceed 
this temperature. 

Treatment for Sulphates. A battery is sulphated only when acid 
is retained in the plates. When the specific gravity of the electrolyte 
has reached a maximum, it shows that there is no more sulphate to be 
acted upon, since during the charge the electrolyte receives acid from 
no other source. Hydrometer readings should be recorded at intervals 
sufficiently frequent (four to six hours apart) to determine if the 
specific gravity is rising or if it has reached its maximum. Continue 
the charge, recording the readings, until there has been no further rise 



276 



Digitized by VjOOQIC 



ELECTRIC AUTOMOBILES 



1? 





120 




-■» 




110 


F= 


-■« 




100 




-■i 

-4 


1 

I 

3 


00 




-1 
-1 






-< 


U5 

it 


00 




-< 


ro 




-1 
— « 
-4 




OP 






7w 










00 






40 






ft: 


90 






u 


so 








10 
















& 



ME 



■.♦it 

♦ w 

♦ ir 

♦ ii 

♦13 
♦14 
■♦W 
♦If 
♦11 
-♦10 
-♦ • 

♦ • 

♦ T 

♦ < 

♦ 3 



in any cell during a period of at least twelve hours. Maintain the level 
of the electrolyte at a constant height by adding pure water after each 
reading with the hydrometer. (If water were added just before taking 

hydrometer readings, the water would 
not have time to mix properly with 
the electrolyte.) Hydrometer read- 
ings should be corrected for any con- 
siderable change in temperature dur- 
ing the charge in accordance with the 
scale shown in Fig. 4. Should the 
gravity rise above 1.300 in any cell, 
draw off its electrolyte down to the 
top of the plates and put in as much 
distilled water as possible without 
overflowing. Continue the charge, 
and if the gravity again goes above 
1.300, it shows that acid has been 
added during the previous operation 
of the battery. The electrolyte should 
then be emptied out, replaced with 
pure water, ajid the charge continued. 
The treatment can only be considered 
complete when there has been no rise 
in the gravity of any cell during a 
period of at least twelve hours of 
continuous charging. 

Upon completion of the treatment, 
the specific gravity of the electrolyte 
should be adjusted to its proper value 
of 1.270 to 1.280, using distilled water 
or 1.300 acid as may be necessary. 
In cases where one or more individual 
cells have become sulphated, while the 
balance of the battery is in good con- 
dition, it is better to remove such cells and treat them individually. 
The active material of sulphated negative plates is generally of light 
color and either hard and dense or granular and gritty, being easily 
disintegrated. It is the negative plates which require the prolonged 



Af 




Fig. 4. Fahrenheit Thermometer with 
Special Temperature Scale for Cor- 
recting Density of Electrolyte 



277 



Digitized by 



Google 



18 ELECTRIC AUTOMOBILES 

charge necessary to restore a sulphated battery. Sulphated posi- 
tives, unless physically disintegrated or badly buckled, are but 
little changed in appearance and can be restored to operative 
condition, although their life will not be as great as if they had 
not been subjected to this abuse. Sulphated plates of either type 
should be handled as little as possible. By strictly following the 
simple rules of operation given in connection with charging and 
discharging the battery, the expense and trouble inseparable from 
restoring a sulphated battery may be avoided. 

Capacity of Ceil. Depends upon Plate Area. The ampere-hour 
capacity of a cell, or the amount of current which it is capable of 
absorbing and reproducing through the medium of the chemical pro- 
cesses described, is determined by the area of its plates. This area 



Fig. 5. Complete Battery of Cells for Pleasure Car 

depends upon the area of the single plate as well as upon the number of 
plates the cell contains. It is customary to make both outside plates 
in a cell negatives, so that the cell contains an odd number of plates 
and its capacity is fixed by the number of positives. The ampere- 
hour capacity of a battery, the cells of which are all connected in 
one series, is the same as that of a single cell in the series; just as, 
in connecting up dry cells or other primary batteries in series, the 
current output is always that of a single cell, while the voltage of 
the battery increases over the voltage of one cell in proportion to 
the number of cells thus connected. The capacity of the cell, in 
turn, limits the safe rate at which its output may be discharged. 
A complete assemblage of cells for a pleasure car is shown in 
Fig. 5. 

Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 19 

Measurement of Capacfty. The standard unit for measuring 
capacity of a storage cell is the ampere hour, which means a cur- 
rent of one ampere flowing for a period of one hour. When the 
capacity of a cell is stated as a certain number of ampere hours, 
this indicates that the cell will deliver 1 ampere of current for the 
period given, 2 amperes for one-half that period, etc. This does 
not mean, however, that this progression may be carried to the 
other limit, as the efficiency of the cell falls away as the discharge 
rate becomes greater. In other words, while a 100-^mpere-hour 
cell will produce 1 ampere for 100 hours, 2 amperes for 50 hours, 
4 amperes for 25 hours, and so on in the same proportion, it will 
be found, as the rate of discharge increases, that the capacity will 
fall off, the same cell not being able to deliver 25 amperes for four 
hours, or 50 amperes for two hours. 

In former years, the capacities of all lead-plate cells for vehicle 
use were bas^d on a four-hour rate of discharge. Thus a 140- 
ampere-hour cell was guaranteed to discharge 35 amperes for four 
hours. Since the introduction and more or less general use of thin- 
ner plates, many makes are sold on a basis of a 5-, 5|-, and even a 
6-hour rate, so that 35 and even 37 or 38 amperes are guaranteed 
for five hours or more from a battery occupying no greater space. 

Rate of Discharge. Since the current is produced by the 
action of sulphuric acid combining with lead in the plates, the rate 
at which the acid can penetrate the active material determines the 
maximum rate at which current can be produced. For instance, if 
the same amount of material used in making a nine-plate cell were 
employed in but two plates, one positive and one negative, the 
ampere-hour capacity at a sufficiently low discharge rate would be 
just the same as if this material were divided into four positives 
and five negatives. At ordinary rates of discharge, however, the 
acid could not penetrate the active material of such a thick plate 
fast enough to maintain the discharge rate for the required time. 
If these same plates were split into thinner plates, the acid could 
much more readily get to that portion of the material which in the 
thick plates was farther removed from the surface, and current 
could therefore be produced more rapidly. 

Safe Discharge Point for Plates. The point to which the cell 
can be safely discharged is not limited by the period during which 

279 • Digit 



20 ELECTRIC AUTOMOBILES 

it is used so much as by the voltage of the cell itself. The dis- 
charge should never be carried so far that the voltage falls below 
1.8 volts per cell, while the voltage when charged should be 2.2 
volts per cell, or slightly in excess of this, especially just after the 
completion of the charge. The majority of vehicle batteries are 
designed to have a normal eight-hour rate of discharge, and their 
capacity, for pleasure cars, seldom exceeds 180 ampere hours. 
Such cells will discharge 10 amperes for a period of 10 hours with- 
out falling below 1.8 volts, provided conditions of charging and dis- 
charging have been favorable, and the battery is otherwise in good 
condition. During the discharge the sulphuric acid, as indicated 
by the chemical equation already given, is partially converted into 
water and lead sulphate, and when carried to extremes, the elec- 
trolyte would be practically all water, and the voltage would fall 
to about 1.46, virtually ruining the cells. However, the sulphion, 
or SO3, is only abstracted from the electrolyte where it is >in con- 



rap 



Fig. 6. Part Section of Exide Storage Cell Showing Complete Assembly 
Courtesy of Electric Storage Battery Company, Philadelphia 

tact with the plates. As it is removed, the density of the fluid 
decreases, and a circulation is set up, thus permitting fresh acid to 
take the place of that exhausted. The chemical action is naturally 
most rapid in the minute pores of the plates where circulation is 

280 Digitized by G00gle 



ELECTRIC AUTOMOBILES 21 

most difficult, so that when the cell is allowed to stand idle, the 
fresh electrolyte penetrates the plates and there is a correspond- 
ingly marked rise in the voltage of the cell. This explains what is 
known as the recuperative power of the storage cell. 

Use of Separators between Plates. In a storage cell for sta- 
tionary service the plates are separated merely by allowing a cer- 
tain space between them, but this would obviously be out of the 
question in a vehicle battery. An insulating separator is accord- 
ingly quite as important a component of the cells as the electrodes. 
Very thin sheets of corrugated wood are generally employed, with 
thin sheets of perforated hard rubber placed on each side of them, 
Fig. 6. These insulating unit groups exactly fill the space between 
adjacent plates so as to permit of no relative movement whatever. 
No matter how well the cell is made, or of what type, where lead 
grids are employed, disintegration of the active material is con- 
stantly going on in service; hence, the plates are placed on strips of 
wood or hard rubber ribs, Fig. 6, to prevent short circuits. 

TYPES OF CELLS 

General Characteristics. It will be noted that there is con- 
siderable difference in the appearance of the various plates illus- 
trated here, and it may be added that there is a corresponding 
difference in their construction. Despite the almost innumerable 
attempts that have been made to discover materials that would 
not have the disadvantages of bulk and weight for storage-battery 
work, the lead-sulphuric-acid type is still commercially supreme. 
Although there are many minor variations of design and construc- 
tion, there are two general classes of lead plates employed. These 
are the Plants and the Faure. In both, lead peroxide is the active 
material at the positive electrode and finely divided spongy metal- 
lic lead at the negative, one of the means of distinguishing the 
plates apart being their color, the negative showing a dull gray, 
while the positive is red. The plates of the Plants type consist of 
pure lead of relatively small sectional area, with all exposed sur- 
faces scored, fluted, or corrugated in similar manner to increase the 
area that can be reached by the electrolyte. 

Pure lead is very soft and yielding, and it is often necessary to 
supply a supporting framework of hard cast lead to lend additional 



281 



22 ELECTRIC AUTOMOBILES 

stiffness to the plates, particularly for vehicle work. These plates 
and the electrolyte complete the Plants type of cell, as the active 
material is directly formed electrochemically from the material of 
the plates themselves by being subjected to a series of charges and 
discharges. In the Faure type, a cast grid of comparatively hard lead 
is employed as the foundation, and the active material is placed in the 
interstices in the form of a stiff paste, the whole plate being subse- 
quently subjected to considerable pressure. On this account it is 
usually referred to as a pasted type of plate. The Exide cell, plates 
of which have been illustrated in part section, Fig. 6, is representa- 
tive of this class. 

Only the Faure type is used for vehicle batteries as the Plants 
is a "formed" plate from which the active material would be shaken 
by the vibration. 

Improved Forms 

Nature of Improvements. The foregoing are what are known 
as flat-plate types of elements, and the life of this form of battery 
is usually measured in terms of the life of the positive plate, as it is 
the latter which suffers most from the charging and discharging 
process. It is nothing unusual for the other elements in the cell 
combination to outlast the positive plate two or three times over, 
new separators being installed with each renewal. Accordingly, the 
problem has been to devise a type of positive plate that would equal 
the negative in durability. Many forms of protective coverings 
designed to prevent the active material from washing out of the 
plate have been tried with varying degrees of success. Among these 
have been plates built up of parallel cylindrical pencils of the active 
material. While the latter did not prove a solution of the problem 
in its simple form, this idea, in combination with a basic principle 
originated by a French maker, served as the foundation for what is 
known as the "Ironclad" Exide type. For this form, the makers 
claim that the positive plate not only lasts practically as long as the 
negative, but that the battery is capable of withstanding the abuse 
of overcharging to a degree never before attained. The importance 
of the latter in the commercial use of electric vehicles can hardly be 
overestimated and is brought out in the paragraphs on "Boosting*', 
Part II. 

282 



ELECTRIC AUTOMOBILES 23 

Ironclad Exide Type. Positive Plate. The Ironclad Exide 
positive plate consists of a grid composed of a number of parallel 
vertical metal rods united integrally to horizontal 
top and bottom frames, the former being provided 
'with the usual conducting lug for carrying the 
current. Each vertical rod forms a core, which 
is surrounded by a cylindrical pencil of peroxide 
of lead, which is the active material. These pen- 
cils are enclosed in hard-rubber tubes having a 
large number of horizontal slits, which serve to 
provide access for the electrolyte, or solution, to 
the active material, but are of such small dimen- 
sions as to practically eliminate the washing out 
of the material. Fig. 7, which shows a vertical 
section of one of these composite pencils, makes 
this construction clear. The outside tubes are 
reinforced by leaving the exposed edge solid, i-e., H 7 Vertical g^ 
without slits. Each tube is provided with two tio > n a °£ p^ ve 

parallel vertical ribs projecting on opposite sides 
at right angles to the face of the plate. These ribs not only serve 
to stiffen the tubes, but, being of hard rubber as are the tubes them- 



Fig. 8. Positive Pencil Fig. 9. Assembled Exide 

Showing Rib Positive Plate 

selves, also act as insulating spacers, allowing the use of a flat piece of 
wood veneer in place of the ribs on the wood separators in other types. 



283 Digitized'byC 



24 ELECTRIC AUTOMOBILES 

The reinforcing rib is shown by Fig. 8, which is a side view of the 
tube. These rubber tubes have a certain amount of elasticity allow- 
ing them to compensate for changes in volume of the active material, 
owing to the expansion and contraction during charge and discharge. 
A complete positive plate of this type is illustrated by Fig. 9. This 
cylindrical form of tube is peculiarly well adapted to perform its 
function, since no amount of expansion or contraction will tend to 
alter its shape, and the internal stresses are thus kept uniform. 
Another advantage is that most of the electrolyte necessary is carried 
within the confines of the plate itself. This is illustrated by a com- 
parison of horizontal sections of portions of the Ironclad Exide plate 
and the standard Exide plate, as shown in Fig. 10. 

Negative Plate. To conform to the construction of the new 
positive, the negative is also modified somewhat, the upper and 



Fig. 10. Comparative Sections of "Ironclad" and Standard Exide Plates 

lower edges of the plates being encased in rubber vulcanized in the 
plate. This eliminates the possibility of short-circuits from material 
bridging across from the positive frames. The negative frames are 
undercut, so that the rubber sheathing is flush and does not project 
beyond the face of the plate. The thickness of this negative plate 
is calculated to provide approximately the same life as the posi- 
tive, thus avoiding partial renewals, which cut down the efficiency 
of the cell. 

Separators. The special form of the positive plates renders 
unnecessary the flat perforated rubber sheet used in the standard 
types of cells, the only separator employed being the wood veneer 
mentioned. The greatly increased life of the new cell made it neces- 
sary to employ a separator of greater durability than those in current 
use and, after investigation, a special kind of wood possessing great 
toughness, as well as ability to resist the action of the electrolyte to 



284 Digitized by G00gk 



ELECTRIC AUTOMOBILES 25 

a remarkable degree, was adopted. These separators are made 
with the grain of the wood running horizontally in order not to 
register with the vertical ribs on the positive plates, which would 
tend to split the wood. The positive and negative plates are 





Fig. 11. PilUr Type of Strap Connectors 
CourUty of Electric Storage Battery Company, Philadelphia 

grouped in the customary manner, the lugs being burned directly to 
the usual lead straps, except that the straps are of the pillar type, 
illustrated by Fig. 11. 

Improved Connectors. Mention has been previously made or 
the necessity of providing the maximum conductivity in the ele- 
ments of the cell as well as in the units of the battery in order to 
keep its internal resistance down, as upon the latter depends its 
ability to discharge its energy at a high rate, this being a valuable 
characteristic for hill climbing or bad road conditions. The usual 
practice has been to employ the same alloy of lead and antimony 
for connecting the cells, the latter having strips of the metal burned 
to the pillars or other projections designed for receiving the inter-cell 
connections. For this purpose, the makers of the Ironclad Exide 
cells have brought out an improved form of connector, shown in 
Fig. 12. This is known as a built-up type, consisting of thin strips 
of copper, lead-covered to prevent corrosion. A number of these 
strips, depending upon the cur- 
rent to be carried, are laid face 

tO face, and their ends Cast into Fig. 12. Lead-Covered Copper Connecting Strip 
lead-alloy terminals, a Special CourUey of Electric Storage Battery Company 

welding process insuring effective and permanent contact between 
the flexible strips and the cast terminal. By this means, good 
conductivity is obtained under all conditions of vibration and tem- 
perature changes. The lead-alloy terminals are ring shaped to fit 
over the pillar of the strap and are burned in place. The use of 
copper gives a higher conductivity than lead alloy, while the lami- 
nated structure provides a flexible, instead of a rigid, connection, 

285 



26 ELECTRIC AUTOMOBILES 

Starting Batteries. The advent of electric starting motors 
on the automobile has been responsible for adding to the problems 
of the storage-battery maker. As outlined in the chapters devoted 
to starting and lighting, the requirements are such that the maximum 
output of which the battery is capable is called for instantaneously 



Fig. 13. Sectional View of Titan Cell Showing Diagonal Ribs of Active 

Material to Lessen Resistance 

Courtesy of Horseless Age 

every time the gasoline motor is started. Any one who has cranked 
a car on a very cold morning after the motor has been idle over night 
will realize the greatly increased effort necessary to move the pistons, 
owing to the adhesion caused by gummed, or partly frozen, lubricating 
oil. Special provision is accordingly necessary to reduce the internal 
resistance of the cells of the battery in order that it may deliver 
its maximum output, the demand usually representing a considerable 



286 



ELECTRIC AUTOMOBILES 27 

overload. One method of attaining this is shown in the "Titan" 
cell, in the positive plates of which the conductivity afforded by 
the grid is greatly increased by the provision of diagonal ribs run- 
ning in the general direction of the points where connection is made 
to the strap, as illustrated by Fig. 13, which shows a section of the 
cell. This increased conductivity tends to reduce the tendency of 
the plate to buckle and force out its active material when sub- 
jected to such a heavy demand for current. 

In addition to the service being of such a severe nature, the 
conditions under which a starting battery must operate are equally 
strenuous in other respects. Touring cars 
are driven at very much higher speeds than 
electric cars and frequently over rough 
roads, which greatly adds to the amount 
of vibration that the plates must endure. 
Special provision must accordingly be made 
for the reception of a greater amount of 
sediment and in a manner which will pre- 
vent the latter from reaching the bottom 
of the plates. This takes the form of an 
increased depth of electrolyte below the 
elements, while the space thus allowed is 

provided with an increased number of Fig 14 Gould startinp Bat . 
baffle plates, or partitions, to prevent the tw ^dsS3 tHlgh 

sediment from being washed about and 

accumulating in one place. The Titan cell is an illustration of this, 
and it is also shown in the Gould cell, Fig. 14, which also incorporates 
the use of built-up connectors of copper and lead. Both of these 
cells likewise embody an improved form of cover. They are 
enclosed by two hard-rubber covers and an intermediate layer of seal- 
ing compound in adhesive contact with the sides of the jar. Sleeves 
of hard rubber permit of some flexibility at the pillars while still 
insuring an air-tight joint with the sealing compound. 

Integral with the lower cover is an expansion chamber communi- 
cating with the interior of the cell and provided with a threaded cap. 
In the case of the Gould cell, leakage is guarded against by the 
inverted conical form of this cap, and as the battery boxes are now 
made in accordance with the S. A. E. standard dimensions, they may 

Digitized by VjOOQ IC 



28 ELECTRIC AUTOMOBILES 

be placed end to end, reducing the thickness to 4| inches in the largest 
size, and permitting the battery to be suspended between the chassis 
frame and the running board, concealed by an apron. 

Edison Battery. Inasmuch as the Edison battery represents 
the only successful attempt to make use of a reaction other than that 
of the lead-sulphuric-acid couple discovered by Plants, the inventor 
of the so-called storage battery, the Edison cell is of unusual interest. 
Placing this battery on the market in commercial form is said to 
have involved the expenditure of more than two million dollars, as 
special processes and costly machinery had to be originated for its 
manufacture, while more than fifty thousand separate experiments 
were made in a period of seven years before the solution of the prob- 
lem itself reached the stage where manufacturing could be undertaken. 

The elements of the Edison cell consist of nickel and iron in an 
alkaline solution, and, as the capacity of a storage cell depends upon 
the area of the active material in contact with the electrolyte and 
upon the conductivity of its members, the problem was to utilize these 
materials in the form best adapted to give efficiency and durability. 
Three years were devoted to this phase of the problem, after the 
reaction giving promise of success had been discovered, before the 
first crude cell was made. 

Composition of Plates. The positive plate of the Edison cell 
consists of vertical rows of thin, perforated steel tubes filled with 
nickel hydrate, these tubes being supported in a steel frame somewhat 
similar in appearance to a pencil-form lead grid, as will be noted by 
reference to Fig. 15, which shows a positive and a negative plate com- 
plete. Rows of flat, perforated steel jackets filled with iron oxide, 
likewise held in a thin steel frame, compose the negative plate. The 
elements are, accordingly, nickel, iron, and steel in a 21 per cent 
solution of potash in distilled water, and these elements constitute 
a storage cell which differs radically in every respect from the lead- 
plate type. In fact, this is the only storage cell the elements of 
which are not attacked by the electrolyte when left standing in a 
charged, partly-charged, or wholly-discharged condition for any 
length of time. Apparently the potash acts as a preservative of all 
the elements entering into the combination. 

Iron oxide will be recognized as one of man's most persistent 
and ubiquitous enemies, rust. Nickel hydrate is the product of a 

2S8 

Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 29 

special electrolytic process originated by Mr. Edison. When on 
charge, this iron oxide, or rust, of the cell's negative plate is con- 
verted into metallic iron, while the oxygen generated passes over 
to the positive plate and converts the nickel-hydrate "content into 
a new form of nickel oxide, previously unknown to science. The 
oxidizing of the nickel hydrate causes it to expand just as the peroxide 



Fig. 15. Assembled Positive and Negative Fig. 16. Completely Assembled 

Edison Plates Edison Cell 

of lead of the lead positive plate does, but there is no danger of 
loosening or loss of the active material in this case, as it is held in 
a rigid steel tube. The latter has numerous fine perforations to 
permit access of the electrolyte, but these are so numerous that the 
steel approximates wire netting or gauze. 

The container is of steel welded in a special machine making 
it an integral unit which cannot be opened without destroying it. 

289 

Digitized by VjOOQ IC 



30 ELECTRIC AUTOMOBILES 

Protruding through the top and surrounded by hard-rubber washers 
are the two tapering terminals, and between them is the filler cap 
through which the solution of potash and distilled water is introduced. 
This cap acts as an automatic relief valve which allows the gas gen- 
erated to escape but prevents the entrance of air. The cells are con- 
nected by nickel-plated solid copper strips fastened to the threaded 
terminals with nuts so that the units of a battery may be taken apart 
readily, Fig. 16. The cells are fitted in wooden trays and tightly 
clamped in place, Fig. 17. 

Advantages and Disadvantages. Chief among the advantages of 
the Edison battery for commercial-vehicle use are its long life and 



Fig. 17. Tray of Four A-4 Edison Cells 

its ability to withstand what would be considered flagrant abuse, 
if applied to a lead battery. It may be charged or discharged at 
any rate within the current-carrying capacity of its connections, 
allowed to stand either charged or wholly discharged for any length 
of time, without injury, and in other ways subjected to electrical 
abuse which would ruin a lead-plate battery in a comparatively short 
time. As evidence of its durability and continued electrical efficiency 
even under such treatment, it is guaranteed for four years' use. 



290 

^Google 



Digitized by VjOOQI 



ELECTRIC AUTOMOBILES 



31 



While the voltage of each cell is but 1.25 volts as compared with 
2 volts for the lead cell, its construction is so much lighter that there 
is a saving in weight in battery of Edison cells when compared with a 











































Charoe 
































t.6 


/ 




























1.0 












Discharge 
































































\ 







S 6 

Fig. 18. Charge and Discharge Curves for Edison Cell 



3 4 

Hours 



lead battery of the same voltage and capacity, despite the added 
number of the former necessary to give the same potential. Fig. 18 
illustrates the charge and discharge curve. 

Size of Battery. The voltage of the vehicle circuit has a two- 
fold bearing upon the latter' s efficiency. On one hand, there is the 
factor of efficient utilization of the energy and, on the other, of 
the charging efficiency of the battery. Thus there is a constant 
loss at both ends which accounts for the abandonment of 24- and 
30-volt batteries which were common in electric cars of the pleasure 
type about 1905. The most common voltage of direct -current 
lighting and power circuits is 110. To charge less than 42 or 44 
lead cells or 60 alkaline cells means a loss of current in the rheo- 
stat, this loss increasing as the number of cells decreases. This 
makes the vehicle owner pay for many more kilowatt hours than 
he receives in the form of energy in the battery. With a 30-cell 
lead battery, for example, charging on 110 volts, one-third of the 
current paid for by the user is wasted, so that it is now customary 
to employ 42- or 44-cell batteries on most of the heavy-type commer- 
cial vehicles, though practice in this respect varies on pleasure cars 
according to their weight, the range usually being from 30 to 42 
cells, the former number being used for light three-passenger vehicles 
and the 40- and 42-cell batteries in broughams and limousines. 
With alternating currents this objection does not hold good. 



291 



Digitized by 



Google 



32 ELECTRIC AUTOMOBILES 

THE MOTOR 

Quite in contrast with that of the gasoline car, the motor of an 
electric vehicle is probably responsible for less of the troubles encoun- 
tered than any other one of the essential components. While the 
relative amount of attention it requires at the hands of the owner 
of the vehicle is small, a knowledge of its construction and w r orking 
will be found of value in the operation and maintenance of the car. 
It is here that the energy held in reserve in the storage battery is con- 
verted into the mechanical power necessary to move the vehicle. 
The reason for the small amount of attention required is apparent in 
the small number of parts as well as their great simplicity, though 
the great amount of attention that has been devoted to the develop- 
ment of the electric motor over a long period of years is largely 
responsible for the elimination of the numerous shortcomings of the 
earlier types. 

Essentials of Motor. The motor consists of a field, an armature 
suitably mounted on bearings so that it may be revolved in that field, 
& frame, a commutator, and brushes. The term field is the generally 
accepted abbreviation for magnetic field, which is the zone of influ- 
ence exerted by a magnet, and is referred to in terms of its "lines of 
force". A common horseshoe magnet, technically known as a 
permanent magnet, will attract to its ends or poles particles of iron 
and steel placed within a certain distance of it. The space bounded 
by the poles of the magnet and the limits to which its attraction 
reaches, is known as its field. With reference to electric motors and 
generators, the word is employed to designate the magnets and pole 
pieces which serve to create this field, rather than the scope of mag- 
netic attraction itself, and it is used to embrace all of them, regard- 
less of their number. 

Principle of Rotation. The fundamental principle upon which 
the functioning of all apparatus of this type is based is to be found 
in the fact that when a current of electricity is passed through a coil 
of wire surrounding a bar or other form of iron or steel, the metal 
becomes magnetic in proportion to the number of turns in the coil 
of wire and the strength of the current employed. Every magnet 
consists of a north and a south pole, and like poles repel while unlike 
poles attract one another. In other words, if two small common mag- 

292 . Digitized by G00gk 



ELECTRIC AUTOMOBILES 33 

nets are placed on a table with their like poles, i.e., north to north 
and south to south, facing one another, the magnets as a whole will 
tend to repel one another, and were they sufficiently powerful, would 
actually recede from the common center until the limits of their field 
were reached. By reversing the polarity of the opposing ends of 
the magnets, they would then tend to be drawn to one another until 
the poles butted. This, in brief, sums up the pfciloSophy of the 
electric motor. 

In order to amplify the power, a large number of magnets are 
employed; and in order that the energy thus developed may be 
utilized, one group of magnets is made stationary while the other 
group is free to revolve. In these two groups will be recognized 
respectively the field and the armature of the motor, and each magnet 
of the groups is of the type known as electromagnets, so termed be- 
cause they are magnetic only while a current is passing through their 
exciting coils. Those of the field may be distinguished as they take 
the form of short thick spokes radiating from the rim or frame toward 
the center. They thus surround the space in which the armature 
revolves, and are ftirther provided with what are known as pole pieces 
in order to fill as much of the space with iron as is possible. As 
already mentioned, the field of a magnet is most powerful in close 
proximity to it and the armature will be seen to run as closely to the 
faces of the pole pieces as good design and construction will permit. 

Now it will be remembered that the direction in which the cur- 
rent of electricity is sent through the exciting coil determines the 
polarity of the resulting magnet. If, with the current traveling round 
the coil in one direction, the right-hand end of a bar becomes of north 
polarity and the left-hand end of south polarity, it will be evident 
that, by reversing the direction of current flow, there will be a cor- 
responding change in the location of the poles. Coming back to 
practice, in which one set of magnets — the field — is held stationary, 
while the other may revolve, it will be apparent that as each of the 
armature magnets approaches a field magnet by virtue of the attrac- 
tion between them, the motion will tend to accelerate up to the point 
where they are opposite, but when the moving magnet passes by, 
the attraction which still exists will tend to stop the rotation. It is 
clear, therefore, that, to bring about the desired rotation of the arma- 
ture some device must be used to reverse the direction of the current 

293 



34 ELECTRIC AUTOMOBILES 

in each electromagnet when it has reached a point opposite the field 
magnet which is attracting it so that the resulting opposite polarity 
may develop a repulsion which will carry the armature in the same 
direction. This is just where the function of the commutator and 
the brushes comes in. The brushes serve to lead the current to the 
circular group of copper bars which forms the commutator, without 
retarding the relation of the armature. Each section of the com- 
mutator is insulated from its neighbors and as the brushes touch 
opposite sections simultaneously the rotation makes the current enter 
the armature coils first in one and then in the opposite direction, 
through successive sections of the commutator, the current being 
reversed and the polarity of the field magnets being changed for each 
new position. 

The Armature. The foundation of the armature consists of a 
cylinder built up of laminations of iron, or punchings, with recesses 
cut into their circumferences to receive the coils of wire, or windings, 
each one of which converts the particular section of the core that it 
surrounds into a powerful electromagnet when the current is passing. 
AlHhe wire employed is strongly insulated, not only to protect neigh- 
boring turns from one another, but each winding is also well insulated 
from its foundation, whether this be the armature or a field core. 
If this precaution were not taken, short circuits or grounds would 
occur. The former term is really self-defining as it shows that the 
current instead of passing round the entire coil or circuit intended, 
would choose the shorter path thus accidentally provided. A ground, 
on the other hand, is caused where non-insulated portions of two 
different wires carrying a current come in contact with the same or 
a connecting piece of metal, or other conducting medium. This 
opens up a path of practically zero resistance for the current, thus 
diverting it entirely from the path it should follow if its energy were 
to be utilized. 

Both short circuits and grounds are things with which the owner 
of the electric vehicle will have to become familiar to a greater or 
less extent in caring for the battery of his car, as well as the remainder 
of its electrical equipment, so that their nature has been explained 
in detail. While both cause similar results, they are not interchange- 
able terms and are employed to convey the distinction mentioned. 
In other words, a ground may be a short circuit, but a short circuit 

294 



ELECTRIC AUTOMOBILES 35 

is not always a ground, as the latter implies the diversion of the cur- 
rent through some normally unused conducting medium, while the 
short-circuit signifies a breakdown of the insulation of the wiring 
or allied appurtenances that permits of the return of the current after 
having traversed but a fraction of the path intended for it. Either 
trouble naturally places the piece of apparatus in which the break 
occurs out of running order until the defect is remedied. In view 
of their nature, grounds are usually much more difficult to locate than 
shoit-circuits. Some of their further causes and results are men- 
tioned in the chapter devoted to the care of the batteries, also that on 
the wiring. 

Capacity for Overloads. It is this capacity of the motor to stand 
excessive overloads that fits in with the requirements of the road, 
for it must be borne in mind that the amount of power required to 
keep a vehicle rolling after it is once started is very small as com- 
pared with the pull necessary to start it, or to accelerate its speed. 
The total amount of energy required is in direct proportion to the total 
weight, and to the square of the velocity. 

Motor Stands 500 Per Cent Overload. The pull, or torque of the 
motor as it is called, must be very heavy at starting, particularly 
when on an upgrade, and also for mounting inclines. For this 
reason, the motor employed is of a type capable of standing for short 
periods as much as 500 per cent in excess of its normal rated capacity. 
It will be apparent that this converts the 2^-horsepower motor into 
one of 12^ horsepower in cases of emergency, without increasing 
its current consumption under the ordinary conditions of load at 
which the greater part of its service is rendered, such as in running 
on the level or ascending ordinary inclines. The available amount 
of power being so closely restricted by the capacity of the battery, 
it will be manifest that this is a most important provision, and as the 
average layman talks in terms of horsepower without adequately 
comprehending the meaning of the latter, electric vehicle makers 
have found it expedient to omit any mention of this factor. The 
electric not only is not intended to be capable of the speeds of the 
gasoline car, but it does not require such an excessive amount of 
reserve power as it has become customary for the manufacturer to 
provide on the latter type. 

Under usual conditions of running, the average gasoline machine 

Digitized by VjOOQ 1C 



36 ELECTRIC AUTOMOBILES 

does not employ more than a small fraction of the available power 
of its motor and, in consequence, is seldom being operated at 
what is technically termed its critical speed, that is, the speed at 
which it is most efficient, and therefore most economical. In the 
case of the majority of gasoline cars, this critical speed is from 25 to 
30 miles an hour, or even higher, while for the average electric car 
it is from 10 to 15 miles an hour, a speed which corresponds so 
nearly with the usual speed on the road that the economy of the 
electric is very great. 

Parts of Motor. The foregoing description of the electric 
motor for automobile use will be clear upon reference to Fig. 19, 



Fig. 19. Parts of Typical Electric Vehicle Motor 

which represents a largely used standard type. In the foreground 
is shown the armature, at the left hand of which is shown the com- 
mutator. The coils of wire on the armature run parallel to its 
length, but in order to save them from injury they are protected by 
a covering and this is in turn held on by the circular bands shown, 
which prevent any tendency of the heavy coils to fly out of their slots 
owing to the effect of centrifugal force. At the commutator end of 
the armature will be seen one of the annular ball bearings upon which 
it runs. This is the most advanced type of anti-friction bearing 
extant, and while its first cost is correspondingly high, its use is justi- 
fied by the great power saving accomplishment as well as the extremely 
small need for attention that it involves. These bearings consist of 
two parallel races and a number of very accurately dimensioned 
balls distributed at equal distances around the circle by means of a 

Digitized by LiOOQ IC 



ELECTRIC AUTOMOBILES 37 

bronze spacer. Only the very finest materials and the most accurate 
workmanship are permissible in successful bearings of this type. 
They are generally employed in electric vehicles, and a further 
reference is made to them in connection with transmission design. 

Directly back of the armature is seen the frame, and from the 
description, the field coils and the pole pieces will be readily recog- 
nizable. The great amount of attention that has been devoted to 
making the motor as compact as possible will be evident from the 
mounting of its accessories. It will be seen that the housings are 
designed to carry both the bearings and the brushes, the latter being 
attached to the inner face of the cover plate shown at the right. The 
parts shown in the illustration comprise the motor complete, even 
including the cap screws necessary to assemble it. 

Motor Speeds. Types of Motor Windings. The speed of elec- 
tric vehicles is a most elusive quantity to the uninitiated, prin- 
cipally because the characteristics of the series-wound motor 
employed are not commonly understood by the layman. The series 
type of motor is one in which the windings of the armature and field 
are connected in series, i. e., so that the entire current fed to the 
motor passes through both of its elements consecutively, so to speak. 
In a shunt-wound motor the field is in multiple with the armature, 
so that, while the entire current pas3es through the latter, the 
amount taken by the field is always proportioned to that required 
by the armature for the load it happens to be carrying. As this 
type of motor is designed for a constant speed, it is not an economical 
motor to use on the electric vehicle owing to the wide fluctu- 
ation of both speed and load imposed, so that its employment is 
comparatively rare in this field. A compound-wound motor is one 
having both series and shunt-coil windings on the fields. Since 
most commercial motors for driving machinery, elevators, and the 
like are of the constant-speed, compound-wound type, there is a 
general impression that the electric car should have a certain nearly 
constant speed for all road conditions. 

Advantages of Series-Wound Motor. But in the series-wound 
motor, the speed varies inversely as the power produced. In other 
words, its torque, or pulling power, is highest at low speeds, which 
is just the requirement demanded in starting or pulling through 
heavy roads. This type cannot be employed for ordinary corn- 
Digitized by VjOOQIC 



38 ELECTRIC AUTOMOBILES 

mercial use, since it will instantly "run away" or race upon the load 
being released, but it can be employed to advantage on vehicles and 
in railway service because it is never disconnected from the load. 
"Load" in this case refers to the effort required to move the vehicles 
rather than the live load. Series motors are employed on the 
electric car because of their higher efficiency, which is of prime 
importance, since the object is to produce the greatest amount of 
useful energy from a given and limited amount of potential energy 
stored in the battery. Just the opposite of the gasoline engine, the 
chief characteristic of the series-type electric motor is the develop- 
ment of increased power with a decrease in the speed. Therefore, 
as the vehicle requires greater power for bad roads or grades, it 
slows down automatically and in a fixed relation to the power 
demanded. 

High-Speed Single Motor Present Practice. Opinion and prac- 
tice are divided on the subject of motor speeds. The higher-speed 
motors are more efficient, are better for grades and starting, but 
mechanical limitations frequently make them undesirable. Where 
formerly motor speeds ranged from 650 to 1100 r.p.m., modern 
practice favors higher r.p.m. rates, ranging from 1000 to 2000. 
Normal speeds under 1000 are not satisfactory for most conditions, 
the use of a low-speed type of motor being one of the causes of the 
low efficiency of the earlier electric cars. Another reason was the 
employment of two motors on comparatively light cars. This had 
a certain advantage in eliminating the differential, but its electrical 
efficiency was very low. Modern practice does not sanction the 
employment of more than one motor on even the heaviest of pleasure 
cars and on commercial vehicles up to 3- or 5-ton capacity. Beyond 
that point practice varies somewhat, some makers employing two 
driving units on the ground that no differential is needed, that 
starting torque is bettered by connecting the armature in series, 
and that damage to one motor will still permit the vehicle to travel. 
These advantages are more than offset by the higher efficiency 
possible in a single and larger electric motor, beside the benefits 
derived from the saving in weight of the motor and from the ability 
of the manufacturer to combine the two speed reductions necessary 
with two motors into one. This avoids some power loss in trans- 
mission from +v, ° motor to the driving wheels. 



298 



Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 39 

THE TRANSMISSION 

Similarity to Gasoline Practice. The types of power trans- 
mission on the electric vehicle have been the same as on the gasoline 
car except that the order of their application has been chronologically 
reversed. The latter started in generally as a chain-driven machine, 
and quite a number of years elapsed before any other method of 
transmitting the power to the rear wheels was attempted. The 
electric, on the other hand, began as a gear-driven car, as the practice 
of direct-connecting electrical generators and power units, which 
first assumed a strong vogue shortly prior to the advent of the 
electric automobile, was taken as a precedent. From the point 
of view of operating conditions, there is considerable similarity 
between the gasoline and the electric machine as far as its power 
transmitting system is concerned. 

Usual Gear Reduction. Owing to weight and space limitations, 
the size of the motor is correspondingly limited, and it is accordingly 
necessary to employ high initial rotative speeds, i. e., a very high- 
speed motor is essential in both cases, while the starting torque or 
pull must likewise be very strong in order to enable the vehicle to get 
under way quickly and to start readily on grades. This necessitated 
gearing down to a very great extent, the usual ratio on the majority 
of the electric vehicles being 10 to 1, i.e., for every ten revolutions 
of the motor, the road wheels make but one turn. In order to accom- 
plish such a reduction without employing gear wheels of a prohibitive 
diameter, it was necessary to bring about this lowering of the motor 
speed by means of two steps, or a double train of gears. Spur, or 
plain straight-tooth, gears were employed at first, and proved to be 
not only noisy, but very wasteful of power. 

They were accordingly replaced by chains in many instances, 
and by gears of special types, such as the herringbone reducing gears 
of the Waverley. In some instances, such as the light Baker runabout 
placed on the market several years ago, it was found possible to drive 
directly from the motor to the rear axle through the medium of a 
single chain, but with this exception the custom of employing two 
distinct reductions of speed was generally followed up to a year or 
two ago. While there were several variations in the manner of 
accomplishing this, the general principle was practically the sam$ 

299 

Digitized by VjOOQ IC 



40 ELECTRIC AUTOMOBILES 

in every instance, a single chain being taken from the end of the 
armature shaft of the motor to a countershaft extending clear across 
the car and having sprockets at each end. The reduction in speed 
from the motor to the countershaft was usually about five to one, and a 
similar second reduction was carried out by means of small sprockets 
on the ends of the countershaft, and large ones on the driving wheels. 
A third class of transmission consists of a combination of gearing and 
chain drive, such as were used on the earlier models of the Woods, 
and the Waverley electrics, the first reduction of which is a silent 
chain. 

Chain Drive. During the past few yecrs, practice in the electric 
field _has closely followed that of gasoline car transmission design, 



Fig. 20. Gear Type of Transmission 

where the final drive is concerned, and in some cases anticipated it. 
But for the advent of several low-priced electric cars, some of which 
have perpetuated the single-chain drive — using a roller-type chain 
and sprockets as the second step in the reduction — this form would 
have practically disappeared. It is efficient and reliable, but not 
as clean and sightly as the shaft type, though this objection may 
be readily overcome by enclosing the chain. Economy in initial 
cost is one of its chief advantages and, in the case of cars which are 
sold at a very low figure, this is naturally of paramount impor- 
tance. ' 



300 



Digitized by VjOOQIC 



ELECTRIC AUTOMOBILES 41 

Gear Drive. The self-contained unit shown in Fig. 20 is an 
illustration of what might be termed an instance of reducing the 
power plant and final drive to the last degree of compactness. Refer- 
ing to the figure it will be noticed that the usual type of motor is 
mounted on a forward extension of the rear axle, the first step in 
the speed reduction being a pair of herringbone gears. Apart from 
this, it is practically a replica of gasoline car practice, as the axle is 
of the full floating type commonly employed on the latter, the second 



Fig. 21. Well-Designed Unit of the Shaft-Driven Type 
with Bevel-Gear Rear Axle 



speed consisting of the usual bevel drive, except that the propeller 
shaft is only a few inches long and consequently does not require 
any universal joints. A somewhat similar type' of transmis- 
sion is employed on the Broc electftes. A full /bating type 
of axle with shaft drive is also a feature of the Borland, this 
form taking its name from the fact that the two driving shafts 
are not rigidly fastened at either end — either the differential or 
the driving-wheel end — the power being transmitted through a 
square-ended section of the shaft floating in the differential and a 
jaw or similar type of clutch at the wheel, the entire weight of the 



,Goo 9 Ie 



Digitized by VjOOQI 



42 ELECTRIC AUTOMOBILES 

car being carried by the tubes or axle housing. An example of a 
single reduction-shaft drive is to be found in the Century, using a 
Timken bevel-gear rear axle. 

An equally compact form which gives a better weight distribu- 
tion is the drive illustrated in Fig. 21. This bears a very strong 
resemblance to the driving unit of a well-known light gasoline car. 
It is a type which affords great rigidity with a very simple con- 
struction. The propeller shaft is practically a continuation of the 
armature shaft, no universal joint being necessary. At its after 
end this shaft meshes with a bevel gear giving a reduction of 2 to 1, 
while a spur-pinion reduction lowers the ratio again 4 to 1, or a 
total of 8 to 1 between the high-speed motor and the driving wheels. 



Fig. 22. Combined Bevel and Spur Gear. Double Speed Reduction 
of the Axle Shown in Fig. 28. 

The arrangement of the two speed reductions in the axle is shown 
by Fig. 22. These bevels have an adjustment by means of a collar 
which caii be loosened or tightened until a perfect adjustment is 
obtained. The larger bevel is mounted on a short jackshaft carried 
on ball bearings on both ends, and upon this shaft is mounted the 
small spur pinion. On each side of the jackshaft is a threaded 
collar which allows for the movement of this shaft either in or out, 
which, in conjunction with the adjustment of the bevel gears, permits 
of a perfect setting of both sets of gears. The housings consist of 
tapering swaged steel tubes which extend from each side of the 
differential housing through the brake housings and the wheels, 
while the driving effort is taken on the combined torsion and radius 
rods pivoted on saddles on the axle just inside the brake drums and 
on the rear end of the motor housing. 



302 



Digitized by VjOOQIC ' 



ELECTRIC AUTOMOBILES 43 

In this, as in all representative types of final drive on electric 
pleasure cars, annular ball bearings are used throughout. One of 
these bearings is shown just forward of the small bevel pinion in the 
two-speed reduction axle. This is an advanced type of bearing 
which the automobile has been largely responsible for developing. 
It is far more costly than even the very best of plain bearings, but it 
cuts friction down to a practically negligible factor, while it will also 
run with a very small supply of lubricant and requires a minimum 
of attention. Such bearings are now universally employed, not 
alone in the electric motors of these vehicles, but also for the coun- 
tershafts an4 wheels, and in similar locations. If the ball bearing 
is not employed, the taper roller type is substituted, the latter 
being very much favored for wheel bearings on both gasoline and 
electric cars, owing to their ability to withstand heavy thrust as 
well as radial loads. 

Worm Drive. Development. What would appear to be the 
ultimate development in electric car transmission, however, has been 
the adoption of the worm drive; and, in taking it up so generally, 
the electric vehicle manufacturers have anticipated what is bound 
to come on the gasoline pleasure car in the near future, as it already 
has in England to a great extent. In this adoption, the history of 
the electric self-starter on the gasoline car has been repeated, in that 
experiments were carried on for a number of years with little progress 
apparent to the world at large, and then, within a comparatively 
short time, the worm drive came into more or less general use. In 
this case, however, most of the research work was carried out in 
England, and a considerable proportion of the worm drives used on 
American electric cars are imported from that country. In itself, 
this form of drive is not a novelty, the Hindley worm drive, made in 
Philadelphia, having been employed on electric elevators for quite a 
number of years. Its successful application to the automobile 
represented far more of a problem than the bevel-gear type as, 
unless correctly designed and machined to the highest degree of 
accuracy, the friction and thrust are excessive and the resulting 
efficiency is low. 

Advantages of Worm-Gear Transmission. Consideration of the 
fundamentals of electric vehicle design, i.e., a light high-speed 
motor and a comparatively slow axle speed, will make apparent the 



303 



Digitized by VjOOQ IC 



44 ELECTRIC AUTOMOBILES 

great desirability of the worm drive in this connection. It repre- 
sents the most practical means of power transmission from a high- 
speed motor direct to the rear axle by means of a single reduction. 
This means saving in weight and the avoidance of the power loss 
entailed through the use of the second reduction in the gear ratio 
otherwise necessary. A further advantage is its silence in opera- 
tion, the worm and worm wheel representing the closest approach to 
this much-to-be-desired feature that is attainable in the transmission 

of power by direct metal con- 
tact. While its initial cost 
is as high, if not higher, than 
even the best forms of double 
reduction, it eliminates sev- 
eral parts, and accordingly 
affords a simpler form of con- 
struction with a more direct 
transmission of the power. 

Details of Worm Drive, 
Rear Axle, and Brake. The 
worm is of alloy steel while 
the worm wheel is bronze, a 
multiple thread of long pitch 
being cut on the former 
while the latter is made with 
a special form of tooth, as 
will be noted by the Rauch 
and Lang worm shown in Fig. 

Fig. 23. Rauch and Lang Worm and Gear 23. This is an American 

type developed by the mak- 
ers of the Rauch and Lang electrics especially for this purpose. In 
both this make and the Woods electric the worm meshes with the 
worm wheel on its upper side, the relation being shown by Fig. 24, 
which illustrates the Rauch and Lang motor and propeller shaft in 
addition. Two universal joints, one of them of the slip type to 
allow for relative longitudinal movement between the motor and 
rear axle, are employed. A brake is placed on the forward end of the 
armature shaft, this showing in the same illustration. Fig. 25 shows 
the complete Rauch and Lang motor and driving unit. A torsion 

304 



ELECTRIC AUTOMOBILES 45 

rod, parallel with and below the propeller shaft, also serves as a 
distance rod between the motor and rear axle and takes all torsional 
or twisting stresses to which the axle is subjected when under power. 
The forward end of this torsion rod is connected by means of a 



Fig. 24. Rauch and Lang Motor, Shaft, Universal Joints, and Worm and Gear 

flexible joint of the ball-and-socket type, with the top of the torsion 
rod link, which in turn swivels on the rear motor yoke. The rear 
end of the torsion rod is taper fitted into a nickel-steel forging, which 



Fig. 25. Rauch and Lang Motor and Rear Axle Unit 

sets into a vertical taper bearing in the front end of the axle housing. 
The method of hanging the torsion rod leaves the rear axle housing 
perfectly free to adjust itself to the relative movement of the axle 
and frame due to the compression of the springs. The latter are of 
the seven-eighths elliptic type, the upper and lower members of 

305 



46 ELECTRIC AUTOMOBILES 



Fig. 26. Rear View of Rauch and Lang Worm Drive Chassis 

which are shackled at the rear ends so that they are flatter than 
usual, thus giving better riding qualities. They are held at three 
points, which decreases the tendency .toward lateral movement or 
side sway, the driving strains being taken on the front ends of the 
lower leaves. The worm and worm wheels are adjusted in perfect 
alignment in assembling the unit, and the latter is housed in, so 
that no adjustments can be made from the outside. Contrary to 
the bevel-gear drive, which in course of time wears out of alignment, 
a worm gear continues in alignment regardless of wear, within prac- 



Fig. 27. Forward End Torsion Rod, Spring Suspension and Brake Details on Rauch and Lang Car 

306 Digitized by GoOgle 



ELECTRIC AUTOMOBILES 47 



Fig. 28. Details of Rear Wheel Brake Construction as Employed on Several Makes 

tical limits, and once properly adjusted can only be deranged by 
subsequent adjustments. A better idea of the various essentials 
of the drive will be obtained by reference to the rear view of the 
Rauch and Lang worm-driven chassis, Fig. 26. As mentioned 
previously, a brake is carried on the armature shaft on this car, the 
second set being of the internal expanding type operating against 
the drums shown attached to the driving wheels, Fig. 27. On the 



Fig. 29. Detroit Worm Drive, Rear Axle and Motor 
Courtesy of Anderson Electric Car Company, Detroit 



307 



Digitized by VjOOQIC 



48 ELECTRIC AUTOMOBILES 

Argo and several other cars both sets of brakes are of the internal 
expanding type, the details of this type of brake construction being 
shown in Fig. 28. 

This is likewise the case on the Detroit electric, the rear axle 
unit of which is shown in Fig. 29, the details of the brake construction 
appearing plainly. The Lanchester (British) type of worm is 
employed on this car. As will be noted from the part sectional 
illustration, Fig. 30, the worm drives through the lower part of the 



Fig. 30. Lanchester Worm Gear Used on the Detroit Electric Car 

worm wheel and runs in a bath of oil, the oil level being shown in 
the figure. In the types previously described, the worm-wheel 
housing itself is partly filled with heavy oil. 

This sectional illustration also shows a marked difference in 
pitch of the worm thread as compared with the Rauch and Lang, 
and makes clear the detail of the mounting. The latter consists 
of a combination radial and thrust annular ball bearing at each end 
of the worm and on each side of the worm wheel. Upon the correct 



308 



Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 49 

alignment of its mounting and proper provision for taking the thrust, 
quite as much as upon correct design and accurate machining, 
depends the success or failure of any worm drive. 

THE CONTROL 

Unlike the gasoline car, in which the control of its speed and 
climbing abilities is divided between a provision for changing the 
gear ratio existing between the motor and the driving wheels, and a 
means of increasing the speed and power output of the motor itself 
through the admission of more fuel and advancing the point of 
ignition, that of the electric vehicle is entirely electric. This is largely 
responsible for its great simplicity, all changes in either direction 
being effected through a single small lever, the manipulation of which 
calls for no more skill than the shifting of a trolley-car controller. 
But there is quite as much latitude of design to be found in the 
methods of control of electrical vehicles as there is in the method 
of transmitting the power to the rear wheels, though, as in the case 
of the power transmission, there is more or less similarity in the 
principles involved 

Counter=E.M.F. Neither a steam engine nor a gasoline motor 
can be given "full throttle" to start it without danger of damaging 
it. This is due to the inertia of the moving parts, which must be 
set in motion gradually and allowed to attain a certain speed 
before full power is developed. As the electric motor has no 
reciprocating parts, and its revolving armature is carried on the 
finest type of anti-friction bearings, the factor of inertia is prac- 
tically negligible in so far as it affects starting. It has already 
been mentioned that the passage of too great an amount of cur- 
rent through a wire, i.e., too great for its carrying capacity, has 
a heating effect. The heating increases in proportion to the 
excess of current flow over the safe capacity of the wire until it is 
sufficient not only to burn off the insulation on the wire, but even 
to fuse the wire itself. 

Now the resistance of the motor armature windings is very low, 
but when the armature is revolving, the electrical resistance is 
increased by two factors — first, a counter-e.m.f., which is developed 
by virtue of the rotation of the armature, and second, the fact that 
the wire in the windings becomes warmer, it being a peculiar and 



309 ,GoogIe 



Digitized by VjOOQI 



50 ELECTRIC AUTOMOBILES 

inexplicable phenomenon that the resistance of a wire increases in 
proportion to its temperature. 

Controller. The inability of the motor to carry more than a 
fraction of its normal operating current when starting makes neces- 
sary the use of something equivalent to the throttle of the steam 
engine for accomplishing this necessary control. As not alone the 
character of the external source of power — in this case the battery 
— is capable of manipulation, but also the internal relations of the 
power-producing elements of the motor itself — the armature and 
the field — are susceptible of various changes, it will be evident that 
the speed range possible under the circumstances may be made as 



Fig. 31. General Electric Controller 

wide as the designer desires. Ordinarily, most electric vehicles are 
provided with a controller giving five speeds forward and two or 
three reverse. 

Drum Type. In the majority of cases, the controller employed 
on the electric automobile is of the drum type, and is practically a 
duplicate on a reduced scale of that employed on street railways, 
except that the automobile controller is what is known as a contin- 
uous torque type. That is, there are no dead spots or idle gaps between 
different speeds, the current always being on except when the con- 
troller handle is at the neutral position. This insures a continuous 
and gradual increase in the speeds without any Jerking between 
the various steps, and prevents a sudden heavy load being placed 

Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 51 

on the motor, as would be the case where a pause was made in shifting 
the handle of the controller over a dead gap. The motor continues 
to run at the lower current value until the next set of contacts on the 
controller is actually delivering a greater voltage or more current. 
The drum, or cylinder, is of insulating material and has mounted 
on it a number of copper segments of substantial thickness. These 
are so spaced that they make contact with corresponding fingers, 
also of heavy spring copper, that are held stationary alongside the 
drum. The copper bars on the drum are "grounded" to provide 
the continuous torque, that is, they have a common return permitting 



Fig. 32. Controller of the Detroit Electric 
Courtesy of Anderson Electric Car Company, Detroit 

the current to reach the motor constantly, i.e., while changing 
speeds. A controller of this pattern is shown in Fig. 31, which is of 
General Electric make. 

The drum in this instance is seen to be but a section of a cylinder, 
on the curved surface of which the spacing of the bars will be ap- 
parent. It will also be seen that there is a corresponding fingef 
making contact with each bar, or in a position to do so when the drum 
is turned to bring it around to that particular point. These fingers 
are held against the drum very firmly by springs. The open socket 
visible at the lower end of each finger is intended to receive the bared 
copper wire of which it represents the terminal connection. A varia- 
tion of this type of controller is shown in the illustration, Fig. 32, and 



311 



52 ELECTRIC AUTOMOBILES 

it will at once be evident that it is provided with a greater number 
of contacts than is the first controller shown. It should be mentioned 
here that the drum is spring controlled as well as the contact fingers, 
and is also provided with notched stops in order to hold the contacts 
on it directly under the ends of the fingers. In the present instance, 
which represents the type of controller employed on the Detroit 
car, the contact fingers themselves are directly attached to leaf 
springs, which are plainly in evidence. The terminals mentioned are 
also to be seen along the bottom, while at the left there is an exten- 
sion of the shaft on which the drum is mounted. This carries a 



Fig. 33. Chassis of Detroit Electric Car 

lever by means of which the drum may be revolved in order to give 
the different speeds, forward and reverse. The latter is generally 
accomplished by means of a pole reversing switch, most frequently 
incorporated directly in the controller itself, and which always 
remains locked under normal running conditions. In order to 
bring the reverse into play, it is usually necessary to depress a small 
pedal or similar release, in order that the driver may not inadvert- 
ently start the car backward. A view of the Detroit chassis is 
shown in Fig. 33. 

Flat Radial Types. A good illustration of a totally different 
form of controller is found in the Rauch and Lang cars, and is known 
as the flat radial type. In the construction of the earlier models 
of the Rauch and Lang car, it was combined with the motor 



312 



ELECTRIC AUTOMOBILES 53 

and countershaft unit, but is now mounted independently and 
in the accompanying illustration, Fig. 34, it is shown separately. 
Instead of being mounted 
on a drum, the contacts are 
placed on a stationary seg- 
ment representing about 
one-fourth of the arc of a 
circle. A pivoted arm, held 
at what would be the cen- 
ter of the circle, is so 
mounted that it may be 
turned in order to make 
contact with the different 
blocks, these in turn being 
electrically connected to the 
terminals shown attached 
to the upright piece at the 

left Of the Controller. Asa Fig34 . Flat Radial Controller 

matter of fact, there are 

two separate series of contacts around the arc, and two movable 

levers arranged to be moved over them. In this case, the moving 



rig. 30. nusn lype 01 controller 



contacts are made of thin copper leaves assembled together and 
are held against the contacts by a spring. 



313 )igitize< 



54 ELECTRIC AUTOMOBILES 

Flush Types. Fig. 35 illustrates a type of controller which is 
designed to be countersunk in the seat of its surface so as to be flush 
with the latter. This is a plan view, showing the controller as seen 
from above, the pattern being one in which the drum is a complete 
cylinder. The left-hand panel of the controller holds the fingers 
and contacts for the forward speeds, while those at the right are 
the reverse speeds, there being four in each direction in this case. 
Further to the right is to be seen the operating lever, the pinion visi- 
ble on the end of the drum shaft constituting part of the mechanism 
for advancing or returning the drum. This consists of a rack in the 
shape of a quadrant which meshes with the pinion in question. At 
the extreme left is shown the spring-controlled stop which prevents 

the drum from being rotated 
more than one space at a 
time in either direction, and 
holds it with the fingers 
pressing directly on the con- 
tacts at each point of its rev- 
olution. The type of control- 
ler employed on the Baker 
cars is shown in Fig. 36. 
Magnetic Type. To fa- 
». «a * i s* * ii a* * t cilitate the handling of the 

Fig. 36. Baker Controller and Operating Lever # ° 

comparatively heavy cur- 
rent that is necessary in starting, changing speed in going up hill, 
and the like, without having to employ wiring of large size to a 
point near the hand-control lever, a modification of the multiple- 
unit system of control as used in electric railway service, and par- 
ticularly on elevated trains, has been applied to the electric auto- 
mobile. In this system only a current of small value is actually 
passed through the hand-controlling mechanism, which takes the 
form of a small "controller box", as shown in Fig. 37, which repre- 
sents part of the control of the Ohio. The controller of the Century 
is shown in Fig. 38. By setting this to the speed desired, current 
is passed through a magnet in the controller proper. The arma- 
ture of the magnet is attracted, and in so doing it closes a switch or 
contact for the corresponding speed. There is a magnet or solenoid 
for each speed ahead and reverse, which are so connected that, in 

3U .Digitized by GoO< 



ElfiCTRIC AUTOMOBILES 55 

changing to a higher speed, the contact of the speed below is not 
broken until either the switch giving the higher current value is 
closed, or the current is shut off, thus releasing all the magnets and 



Fig. 37. Control Disk of the Ohio Magnetic Controller 
Courtesy of Ohio Electric Car Company, Toledo, Ohio 

obtaining the advantages of the continuous-torque type of hand 
controller. The arrangement effected by the opened and closed 
positions of the various magnets determines the direction and 



Fig. 38. Magnetic Controller of the Century Electric Car 

magnitude of the current in the motor circuit in a similar manner 
to that provided by the segments and fingers of the drum controller. 
The essential difference between the magnetic controller and the 

315 Digitized by G00gle 



56 ELECTRIC AUTOMOBILES 

ordinary type is that the former is electrically operated, while the 
latter is mechanically operated. Hence its location is not governed 
by the necessity of mechanically connecting it with the hand lever 
through rods, gears, or chains, and it may be placed in any con- 
venient location. In the Ohio it is placed under the seat. The 
various speeds are obtained by turning the disk on the end of the 
contactor box near the driver's hand. Turning to the right gives 



Fig. 39. Wiring Diagram for Primary Circuit of the Ohio Magnetic Controller 

the various forward speeds in consecutive order. The neutral 
position is as far to the left as the disk will go; by pushing the button 
on top the centnoHer may be turned still further to the left to give 
the reverse speeds. When in the neutral position it may be locked 
there by pushing in the button at the back, and the controller cannot 
then be operated until unlocked with a key. Buttons are also pro- 
vided for ringing the bell and operating the magnetic brake. The 
contacts are made by spring-held carbon brushes pressing against 
the inner face of the disk. In this system of control there are two 
independent circuits — the primary circuit passing through the mag- 

316 



ELECTRIC AUTOMOBILES 



57 



netically-operated switches of the controller from the battery to the 
motor, and the secondary circuit, which handles the current of 
lesser value employed to operate the magnets, and which is controlled 
by the movement of the disk mentioned. The primary wiring 
diagram of the Ohio is shown in Fig. 39, and the secondary wiring 
diagram in Fig. 40. 

Duplex Control. To facilitate the handling of closed cars of 
the brougham and other large types of enclosed cars seating five or 
more passengers, duplicate-control wiring and duplicate-brake pedals 



s Brake Push Button 




Speed Switch Located on 
£nd of Contactor Box 



^Open When 3 *& Contactor Comes In 
Fig. 40. Wiring Diagram for Secondary Circuit of the Ohio Magnetic Controller 

are provided at two positions; one forward, designed to be operated 
from a front seat, and the other similarly located with relation to 
the rear seat on the same side. Brake pedals and steering connec- 
tions are also duplicated, so that to shift the control of the car from 
one location to the other, it is only necessary to release the steering 
column at one place and insert and lock it in the socket provided 
for this purpose at the other. This enables the driver to keep the 
way clear ahead no matter how many passengers are carried and 
also drive from the rear seat when the load is light. 

Care of Controller. The contacts of the hand-operated type of 
controller should be inspected at intervals to note whether they are 



317 



Digitized by 



Google 



58 ELECTRIC AUTOMOBILES 

making proper contact or not. In case the spring of one of the fingers 
loses its tension, an arc is apt to form between it and the segment 
on the drum and burn the metal. The presence of such an arc will 
be noted by a peculiar hissing sound which will be plainly audible if 
the cover of the controller box is removed and the car run in a com- 
paratively quiet place. This action will also take place to a certain 
extent if the controller is held between the notches in changing 
speed. The blistered surface of the metal thus resulting will make 
poor contact, and will continue to burn more and more unless this 
condition is remedied by sandpapering the finger and correcting 
the tension of the spring so that contact is made all over the surfaces 
that touch. If a finger has become badly burned, it should be 
replaced and the new one adjusted to an even, moderate tension. 
When necessary to face the fingers to the drum, the sandpapering 
should be done on the fingers themselves rather than on the seg- 
ments of the drum, as the latter are not so easy to replace. The 
drum segments should be kept bright and clean, and should be 
lubricated occasionally by wiping with a linen rag and some vaseline. 

Methods of Control. As it is equally important for the owner 
of an electric vehicle to familiarize himself with the manner in which 
the amount of current sent through the motor is controlled, quite 
as much as with the apparatus for effecting this, it has been thought 
advisable to devote a short section to this subject. Before taking 
up this matter, it will be well to return momentarily to a previously 
discussed subject of series and parallel connections. 

Series and Multiple Connections. Each cell of a storage bat- 
tery is a complete self-contained unit capable of delivering cur- 
rent of a certain amount according to its size and capacity, at an 
electrical pressure of slightly more than two volts when fully charged. 
For purposes of illustration, each individual cell may be likened to a 
pump, capable of exerting a pressure of two pounds. It will be quite 
apparent that if 24 such pumps, corresponding to the 24 cells .of a 
48-volt storage battery, were connected together — the outlet of the 
first to the inlet of the second and so on throughout the entire 24 — 
the series of units would be capable of producing a pressure of 48 
pounds. The water delivered could accordingly be forced 24 times 
as far, or as high, as one pump could send it, but the quantity raised 
would only be that of which one unit was capable. This analogue 

318 



ELECTRIC AUTOMOBILES 59 

affords a very clear idea of what is meant by a series connection, as 
the statement just made regarding the ability of pumps so connected 
applies literally to the storage cells under the same conditions. Again 
taking the 24-cell battery as an illustration, this being the former 
standard for light pleasure vehicle use, it will be seen that the 
output of the battery connected in series, i. e., the positive of one to 
the negative of the next and so on throughout the set, would be the 
ampere-hour capacity of one cell at 48 volts. The voltage is seldom 
constant, but ranges from 2.2 to 1.7 volts per cell, according to the 
state of charge that the cell is in at the time; but when a number of 
cells are connected in series, the voltage of the battery thus formed 
will always be that of the voltage of one cell multiplied by the num- 
ber in the battery. For purposes of reference, it is customary to 
consider the potential of the storage cell as 2 volts. 

To return to the analogue of the pumps, where the conditions 
are such that a greater quantity of water is required, but it is not 
necessary to raise it to more than half the height to which the 24 
pumps in series are capable of sending it, they may be arranged in 
two series of 12 each. Double the volume of liquid may then be 
raised to a height represented by the ability of the 24-pound pressure 
developed. The two groups of pumps are still in series, so far as 
they alone are concerned, and each group would have but the capacity 
of a single pump at twelve times its pressure. But when the inlets 
and the outlets of the two groups are brought together in the case of 
either pumps or storage cells, the volumetric capacity is increased to 
two units at a pressure of 24 pounds or volts. If, on the other hand, 
all the inlets were brought together into one connection and all the 
outlets into another, there would result a capacity of 12 pumps, at 
the pressure of but one. This last-named arrangement is termed 
a multiple connection, while that described above is a combination of 
the series and multiple connections, and is accordingly designated by 
the term series^midtiple. 

Given 24 cells or more, the number of series-multiple combina- 
tions possible is quite extended, but it will be evident that those at 
either extreme of the range would be useless for all practical purposes 
in the running of an electrical vehicle. It is accordingly customary 
to assemble the cells in sets of six or eight connected in series, which 
cells are securely packed in oak cases, the number of the units < 

Digitized by VjOOQ IC 



60 ELECTRIC AUTOMOBILES 

employed depending upon the voltage of the motor of the 
vehicle. 

Resistance in Circuit. Another source of control is to be found 
in the motor itself. It will be recalled that the latter generates power 
by means of the alternating magnetic attraction and repulsion of 
the sections of the armature by the field magnets. The strength of 
the latter, as veil as that of the electromagnets composing the arma- 
ture, is naturally dependent upon both the amount of current sent 
through them and its voltage. One of the simplest forms of con- 
trol is naturally that in which the entire battery is in series with 
the motor, and in which the relation of the two undergoes no change. 
In such a case, resistances of the type shown in Fig. 41 are employed 



Fig. 41. Controlling Rheostat 

to cut down the current sufficiently to give what are usually termed 
the starting speeds. In every case, the full energy of the battery is 
being drawn upon, but only a part is being utilized on these first 
speeds, the remainder being dissipated by the resistance in the form 
of heat. In view of the very short period during which they are em- 
ployed, the use of resistances in these starting speeds is not a detri- 
ment. This system of control is to be found on the Rauch and Lang 
cars, among others, and has the great advantage of discharging all 
the cells of the battery uniformly. All the speeds are obtained at 
the same voltage and the motor is working at every position of the 
controller handle, so that there are accordingly no dead spots and 
the circuit is never open, even momentarily. A similar system of 



320 



Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 61 

control is employed on the Baker vehicles. This will be evident 
upon a little study of the accompanying diagram, Fig. 42, illustrating 
the wiring and all the connections. The large squares, marked plus 
and minus, represent the groups of cells into which the battery is 
divided. The individual cells in each group are connected in series 
and it will be seen by tracing the connections that the groups are like- 
wise in series, a positive being connected to a negative and so on 
throughout. 

Wiring Diagram. Wiring diagram^ appear extremely intricate 
to the uninitiated at first, sight, but in each instance the course taken 
by the current may easily be followed after a little study, and as 
familiarizing himself with all the wiring and connections of his car is a 



Fig. 42. Control Wiring Diagram 

part of the education that no electric vehicle owner should overlook, it 
should not be slighted. The diagram received from the manufacturer 
of his car will be a Wue print similar to the one from which the 
accompanying illustration was taken, so that it may be studied here 
as well as at first hand. Familiarity with one of these diagrams will 
prove an "open sesame" to all others, for, while they all differ to a 
greater or less extent, it will be easy to trace the different circuits, 
once the rudiments are known. % 

The fact that all of the cells in the battery are in series has 
already been mentioned. It will be seen that there are 24 cells in 
the battery, giving a working potential of 42 to 60 volts according 
to the state of charge. The different points of the controller are 
represented by the group of parallel bars in the lower center of the 

321 

Digitized by VjOOQ 1C 



62 ELECTRIC AUTOMOBILES ' 

drawing, marked i?-4, R-2, etc. In this case it will be noted that 
there are four connections of this nature, R-l to RA, these represent- 
ing resistances to cut down the current for starting. They are accord- 
ingly known as starting speed*, and are only designed for getting the 
vehicle under way, an operation that calls for a heavy torque or pull 
on the part of the motor. This requires a large amount of current 
and, as already mentioned, it would be apt to burn out the motor 
windings if sent through the latter before it had attained sufficient 
speed to build up its counter-e. m. f . to a point where the full cur- 
rent may be safely handled. The external resistances themselves 
are represented by the bars marked in the same manner, seen diago- 
nally to the left and above the controller on the diagram, the connec- 
tions between the 'two being easily traceable. 

Further points on the controller are designated as FA and F-2, 
and FF-l and FF-2, and refer to the connections for altering the rela- 
tion of the field and armature. Electric motors employed on auto- 
mobiles are generally of what is known as the series type in which 
the armature and fields are normally in series with one another. In 
other words, the entire current passes through the complete winding 
of the motor. By varying this relation in several ways, several steps 
in the speed control are possible without the intervention of any 
resistance. For instance, in the control, as illustrated, the first speed 
is obtained by placing the field, in series with a resistance, giving a 
car speed of 8 miles an hour. By cutting out part of the resistance 
and still maintaining the same relation, the car speed is increased to 
10 miles an hour, corresponding to the second point on the controller. 
At the third point, the resistance is eliminated altogether, resulting 
in an increase to 12 miles an hour. A further increase to 14 miles 
an hour is obtained by shunting the fields, while the fifth speed of 16 
miles an hour results from placing the field in series-multiple. The 
last point on the controller shunts the series-multiple field and gives 
19 miles an hour. 

Office of the Shunt. The term shunt may be explained by 
turning again to the water analogy. Electricity, water, or any- 
thing else under pressure will naturally follow the path of least 
resistance. Take, for instance, a two-foot water main', with a one*- 
inch outlet tapped into it. The amount of water that will flow 
through the one-inch pipe is not alone dependent upon the pressure 

322 t 

Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 63 

in the main, but likewise upon the resistance offered by the one-inch 
pipe. This, by analogy, is practically an application of Ohm's law. 
Substitute for the water main an electric circuit. At a certain point, 
connect to it a by-path in the shape of another circuit of smaller 
wire, and in consequence, representing a greater resistance. The 
current can pass through these two circuits simultaneously and 
the amount of current in the second, or shunt circuit, will be 
smaller than that flowing in the main circuit. In fact, the current 
will divide itself inversely as the resistance; that is, if a shunt has ten 
times the resistance of the wire in the main circuit between the ter- 
minals of the shunt, this shunt circuit will carry only one-tenth of the 
total current. 

The best example of a shunt connection is to be found in the 
case of the volt-ammeter, as shown in Fig. 42. For convenience, the 
voltmeter and ammeter (ampere-meter) are combined in a single case 
as if they were one instrument, but it will be noted that the connec- 
tions are the same as if both were independent. As the voltmeter is 
always in circuit, whether the car is running or not, it is wound to a 
very high resistance so as to consume the minimum amount of current 
for its operation. The shunt marked on the lower part of the diagram, 
just under the position of the instrument, is really a part of the am- 
meter, itself. Where only small quantities of current are to be meas- 
ured, the full strength is usually passed directly through the am- 
meter, but on an electric automobile, this would not be practicable 
in view of the wide range and the sudden variation of the storage- 
battery current, which in starting frequently takes the form of a 
heavy surge. The instrument is accordingly designed to employ but 
a fraction of the total current, this fraction bearing a direct relation 
to the total current passing, the scale reading of the ammeter being 
the same as if the full strength of the current passed through it. 

It will be evident that any circuit, such as the field winding 
of the motor, when placed in shunt with its supply circuit, will only 
take an amount of current depending upon the ratio between its 
resistance and that of the main circuit, and that economy in current 
consumption results. This explains its employment for two of the 
higher speeds of the car, the wiring diagram of which is illustrated in 
Fig. 42. It will be noted that this connection is only employed for 
the higher speeds; in one case, the field windings being in series them- 

323 



64 ELECTRIC AUTOMOBILES 

selves, and the whole in shunt with the main circuit, to give 14 miles 
an hour; and in the second, the field windings themselves being in 
series-multiple and in shunt with the main circuit to give a speed of 
19 miles an hour. This is due to the fact that at the higher speeds, 
only a relatively small amount of power is required to keep the ma- 
chine moving. Electric vehicles as a rule do not run at speeds high 
enough to make wind resistance a factor of great importance, and as 
a result operate under ideal power conditions when once under way. 
In other words, the draw-bar pull, by which is meant the effort neces- 
sary to keep the vehicle moving, is very light. At starting, however, 
in common with other cars, it is heavy, so that it will be evident that 
the shunt connection is not applicable to the starting speeds. Its 
r6le is that of economy, rather than power, and to obtain the latter 
the series connection is necessary. 

Fuses. The fuses are a part of the electrical equipment of the 
car, mention of which may be appropriately made in this connection, 
as their function is that of acting as a safety valve in the control. The 
varying resistances of different kinds of metals have been explained, as 
well as the heating effect incident to sending a current through a wire, 
particularly where the latter is of a size too small to carry the current. 
It is well known that lead and similar materials have a very low melt- 
ing point, and advantage has been taken of this in connection with 
the phenomenon just referred to, to make what are known as electric 
fuses. These are strips of lead alloy of accurately determined sizes, 
each size being designed to carry a certain amount of current at a 
certain voltage. This is known as the capacity of the fuse, and be- 
tween it and the amount of current that the motor or other apparatus 
which the fuse is designed to protect can safely stand there is an 
ample margin of safety. In consequence, whenever there is a rush 
of current through the circuit, as when the controller lever is pushed 
sharply forward toward the full on point, and the brakes happen to 
be holding the car, the fuses will "blow out" or melt, and save the 
motor from destruction. 

Electric Brake. In addition to the usual mechanical brakes, the 
construction of which is along lines practically identical with those 
employed on gasoline cars, some manufacturers equip their cars with 
an electric brake. Just how this acts will be clear from a perusal of 
the chapter devoted to a description of the motor and its method of 

Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 65 

operation. It will be evident that upon reversing the function of the 
motor and driving it from an external source of power, which in this 
case will be the motion of the car itself, it will act as a generator 
of electric current, and in doing so, it will absorb power in proportion 
to the speed at which it is driven. Connections are accordingly 
provided on the controller to permit of this, but the motor provides 
such an extremely powerful brake, that this has been regarded as a 
disadvantage in some cases, so that certain makes of electrics are 
only equipped with mechanical brakes. 

This disadvantage is doubtless due to the fact that the series 
type of motor ordinarily employed on the electric car does not lend 
itself readily to this service. Its braking power increases as the 
square of the speed of the car, i.e., at sixteen miles an hour, the effect 
is four times as great as at eight miles, and when suddenly applied 
this is apt to stop the car very suddenly, much to the detriment of 
its tires and mechanism, if not to the occupants themselves. Should 
a small particle of dust or burnt metal lodge on a contact and momen- 
tarily prevent the brake from "taking hold", the motor will suddenly 
"build up", with disagreeable results. 



325 



■s 

M - 

I 1 

2 « 

B *• 

3 i 

M S 

2 8 

8J 

? 



326 Digitized by GoOgle 



ELECTRIC AUTOMOBILES 

PART II 



CARE AND OPERATION OF THE ELECTRIC 

CHARQINQ THE BATTERY 
SOURCES OF CHARQINQ CURRENT 

Sources of Direct Current. Small Generators. There are few 
towns, or even villages, in this country at the present day that cannot 
boast of electric-lighting facilities, so that the owner of an electric 
vehicle will find it possible to obtain charging current for the main- 
tenance of this type of automobile regardless of where he lives. 
In case he should reside too far outside the corporate limits of a village 
to find such service at his command, or in case he is of a sufficiently 
mechanical turn of mind to undertake it, he will find apparatus for 
generating the current on his own premises available for a com- 
paratively moderate outlay. Though not the simplest, a small direct- 
current dynamo driven by a gasoline engine requires but little attend- 
ance, and will prove by far the most economical method of charging. 
This is particularly the case where the generating set's chief employ- 
ment is that of lighting the house, although where an isolated plant 
may be installed, the owner of an electric vehicle will find it a great 
advantage for charging purposes alone. 

This may be seen from the fact that in small towns and villages 
rates for electric current are usually high. The power unit, the watt, 
has already been explained. A kilowatt is 1000 watts, and electric 
current is sold by the kilowatt hour, which means the employment 
• of one kilowatt of current for one hour. Where current is purchased 
in comparatively small quantities, the rate is seldom less than 10 cents 
per kilowatt hour, and sometimes 15 cents, or more. With an ordi- 
narily efficient generator and gasoline engine, current may be pro- 
duced in a small isolated plant for less than 5 cents per kilowatt hour. 

The average runabout battery requires 75 to 80 ampere hours 



327 Digitized by G00gle 



68 ELECTRIC AUTOMOBILES 

for a charge, while a surrey, phaeton, victoria, brougham, or simi» 
lar type will need 100 airipere hours. 

Service Mains. If the current be taken from the service mains 
at 115 volts, the charge for the runabout battery would be 75X115 
= 8625 watt hours, or more than 8| kilowatt hours. The cost of 
this would be 86 cents at a 10-cent rate. Even where current is to 
be had at more favorable rates, such as 7 or 8 cents a kilowatt 
hour, a small engine and dynamo are very much more economical 
where no extra attendance has to be figured on. 

Sources of Alternating Current. Turning now to the usual 
source of electricity, the alternating current, one is confronted with 



Fig. 43. Motor-Generator Set, 115 A.C. to 125 D.C. 

the fact that the charging current -must in all cases be "direct," never 
"alternating.' 9 

Alternating current has been found much more practical for 
long-distance transmission and distribution, and its use is now very 
general throughout the country, so that where the owner of an 
electric vehicle decides to fit up his own garage for storing and 
charging the car, the first thing to be considered will usually be 
some means of rectifying the alternating current, that is, making it 
direct. This may take several different forms, such as the motor- 
generator set and the mercury arc rectifier, but for reasons which 
will be made plain the mercury arc rectifier will be found the most 
practical and economical apparatus for the purpose. 



328 



Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 69 

Motor Generator. Where there is a considerable amount of 
charging to be done, the motor-generator set is frequently employed. 



Fig. 44. MoWr-Generator and Charging Panel for Charging Twelve Electric Trucks 
Courtesy of Curtis Publishing Company, Philadelphia 

This consists of an alternating-current motor and a direct-current 
generator combined in a single unit, both armatures being on the 
same shaft, the supply current simply being utilized to run the 
motor. A set of this kind is shown in the accompanying illustra- 
tion, Fig. 43. The apparatus is designed to take alternating cm> 
rent at 115 volts and generate a direct current at 125 volts. In 
Fig'. 44 is shown a very well-arranged and complete motor-generator 
charging plant. 

Mercury Arc Rectifier. Owing to its simplicity, as well as to 
the fact that it is entirely automatic in action, the mercury arc 
rectifier has come into very general favor for storage-battery 
charging on a small scale. The apparatus itself is shown in 
Figs. 45 and 46, giving, respectively, a front and rear view; the 
connections are shown diagrammatically in Fig. 47. It will be 
seen that the panel board of the instrument incorporates every- 
thing necessary for regulating the charge, including a voltmeter, an 
ammeter, resistance, main switch, starting switch, circuit breaker, 

329 

Digitized by VjOOQIC 



70 ELECTRIC AUTOMOBILES 

and fuses. The circuit breaker is a device designed to protect the 
apparatus with which it is connected by opening the circuit when 
there is an excess of current, or when the current supply is acci- 
dentally cut off. By opening the circuit as soon as this occurs a 
rush of current through the apparatus is prevented when the serv- 
ice is resumed. Should it fail to act, the fuses represent the 
second step in the protective link, but naturally their only func- 



Fig. 45. Switchboard, Fig. 46. Switchboard, 

Front View Rear View 

tion is to rupture the circuit by melting under the heating effect of 
an excessive flow of current. 

The mercury arc rectifier consists of a glass vessel, Fig. 48, from 
which the air has been exhausted and a certain quantity of metallic 
mercury inserted. The tube also has fused into the glass the several 
connections necessary. The one negative terminal, called the cathode, 
is sealed into the bottom of the tube while two positive terminals, 
called anodes, are on opposite sides and a short distance above the 
cathode. The anodes are graphite and the cathode mercury. When 

330 

Digitized by VjOOQ 1C 



ELECTRIC AUTOMOBILES 



71 




Fig. 47. 



Wiring Diagram for Mercury Arc 
Rectifier Circuit 



at rest, there is no electrical connection between them. A starting 

anodes is accordingly provided. If the tube be rocked gently after 

the switch has been closed, an 

arc is established between these 

two points. This liberates 

sufficient mecury vapor to 

start the main arc ; the starting 

switch is then opened. An 

automatic starting device for 

use when charging at night, 

takes the form of a shunt coil 

and a solenoid, in which a 

plunger operates. When the 

arc is broken, the current is 

shunted through this solenoid 

andtheplungershakesthe tube 

gently, thus re-establishing the 

arc and continuing the charge. 

METHOD OF CHARQINQ 

Making Proper Connec- 
tions. Batteries are not usu- 
ally shipped with the vehicle 
itself, but are packed sepa- 
rately in a charged condition; 
as a freshening charge is re- 
quired before the battery is 
used, it will prove an advan- 
tage to carry this out before 
placing the battery in the car. 
The groups of cells must be 
connected in series — the plus 
terminal of one group to the 
minus terminal of the next, and 
so on, the final positive and negative terminals of the entire set being 
connected respectively to the positive and negative terminals of the 
source of the charging current. The charging current must flow into 
the battery at the positive pole; a wrong connection will not 



FI3. 48. Mercury Arc Rectifier Tube 



331 



Digitized by 



Google 



72 ELECTRIC AUTOMOmLES 

only fail to charge it, but will do a great deal of damage and seriously 
impair the life of the battery. 

Determining Polarity. Where the polarity of the charging ter- 
minals is unknown, the simplest method of determining it is to take 
a glass of water into which a few drops of acid or a little salt has been 
put. Place the wires in it, taking care to keep them well separated. 
Bubbles of gas will form on both of the wires, but one will give off 
gas much more freely than the other. This is the negative pole and 
should be attached to the negative charging terminal of the battery. 
The other wire will give off comparatively little gas and will rapidly 
blacken. This is the positive pole. There are numerous other 
tests equally simple, but as this calls for apparatus easily obtained 
anywhere, it will be an advantage to memorize it, particularly 
as occasions will arise when the vehicle will have to be charged away 
from home in the absence of the usual facilities. The wire or con- 
nections to the battery from the charging side must be of ample 
size to carry the heaviest current used in charging without undue 
heating. The sizes used in the car itself form the best guide for this. 

Voltage After Charging. The operation of charging will be 
the same whether the battery is in or out of the vehicle, but as the 
battery was fully charged when shipped, this initial charge will be 
a short one. But the greatest care must be taken to charge the 
battery fully. The voltage per cell should reach 2.55 volts, with the 
current still on, when the cell is fully charged. This would mean 
GO to 62 volts for a 24-cell battery. 

These voltages, Table II, are approximate and are intended for 
guidance only. A battery when cold will show a higher voltage than 
one at a higher temperature, and the same thing is true of a new 
battery as compared with an old one. It is not safe to regard a fixed 
voltage as the end of the charge, but a maximum voltage for the 
battery in question. 

The rubber plugs should be removed from the cells during the 
operation, as the cells will be gassing very freely toward the end of 
the charge. This gas is hydrogen and, as it is not only highly 
inflammable, but likewise very explosive when mixed in certain pro- 
portions with oxygen, care must be taken not to bring a naked flame 
anywhere near the battery while in this condition. The plugs may 
be left out for a short time after the charge is finished to permit the 



332 ^ 

^Google 



Digitized by VjOOQI 



ELECTRIC AUTOMOBILES 

TABLE II 
Charging Voltage for Lead Batteries* 



73 



"l -■ - ■ L = — . — - — ■ 1 


Volts At 


Ntjmbeb of Cells 








Start 


Finish 


12 


26 


31 


14 


30 


36 


16 


34 


41 


18 


39 


46 


20 


k 43 


51 


22 


47 


56 


24 


52 


61 


26 


56 


66 


28 


60 


71 


30 


64 


76 


32 


69 


81 


34 


73 


87 


36 


77 


92 


38 


82 


97, 


40 


86 


102 


42 


90 


107 


44 


95 


112 


46 


100 


117 


48 


105 


123 


50 


110 


128 



♦Cushing and Smith, Electrical Vehicle Handbook. 

escape of the gas. The latter carries more or less of the acid elec- 
trolyte with it in the shape of a fine spray, and care should be taken 
to keep this spray from falling on the clothes or similar objects, as it 
-causes ruinous stains, and only a comparatively small quantity is 
required to burn holes in cloth. 

Temperature of Battery. When the battery is out of the vehi- 
cle, as in the case under consideration, the matter of temperature is 
not so important, but when it is in the vehicle, precautions must be 
taken to provide all possible ventilation. The charging causes a rise 
in the temperature of the cells and this should never be allowed to 
exceed 110° F. under any circumstances. The lower it can be kept 
the better, and a battery which is never allowed to exceed 90° F. 
while under charge will last much longer and give better service. 
The reason for this is to be found in the fact that the heating causes 
the active material in the grids to expand. If this expansion be 
excessive, as where the temperature is allowed to get too high, 
the material is apt to bulge completely out of the retaining pockets, 
so that it does not return when cooled off again. This destroys its 



333 



Digitized by 



Google 



74 



ELECTRIC AUTOMOBILES 



connection with the lead grid, cutting down its conductivity and 
greatly lowering the efficiency of the cell. Furthermore, after this 
bulging of the paste has occurred, there is the possibility at any 
time that flakes of active material will drop down below the plates 
and cause a short-circuit. Even if it does not cause this trouble, 
the accumulation of the material in the bottom may soon be enough 
to short-circuit the whole cell unless it is of the type provided with 
an especially deep space below the plates. The temperature should 
accordingly be noted from time to time during the charge and, if 
it passes safe limits, the charging rate must either be reduced or 



IN 


I 


(1 


1 

*6 


Put 




rty 


1? 



-l'4ff- 



1— e #U 

Fig. 49. Typical Battery-Charging Rheostat 
Courtesy of General Electric Company, Schenectady, New York 



^JU-i 



discontinued altogether in order to give the cells an opportunity to 
cool off. 

Experience has shown that the best results are obtainable from 
a storage battery when its temperature is maintained between 70° 
and 90° F. during both the charge and discharge. A considerably 
lower temperature will materially reduce the available charge of the 
battery, but this does not tend to injure it in any way, as a return to 
normal temperature restores its capacity. This is not true of a 
higher temperature, however, for if it is kept above normal for any 
length of time the wear on the plates is excessive. 

Charging Rate. Every battery has a certain charging rate, and 
this should be taken from the chart sent with it by the manufacturer. 
It will be found that there are two rates — a starting rate and a 
finishing rate — and, as it is during the final part of a charge that the 
greatest wear falls on the battery plates, instructions regarding the 
strength of the current to be employed for starting and finishing the 



334 



Digitized by 



Google 



ELECTRIC AUTOMOBILES 75 

charge should be closely followed. The more slowly a battery can be 
charged within reasonable limits, the better will be its condition at 
all times, and the longer its life. It is not always convenient, how- 
ever, to give a battery as slow a charge as desirable in electric vehicle 
work. On the contrary, the car is often wanted at short notice not 
long after the battery has been discharged, and consequently it 

is abused by being charged, at 
an injurious rate for a short 
period. Theoretically, 10 am- 
peres for ten hours and 50 
amperes for two hours are the 
same and should give a battery 
capacity of 100 ampere hours. 
Instructions furnished by the 
manufacturer as to rates of 
charge should be noted and 
carefully complied with by the 
owner. 

The manufacturer specifies 
that each type of cell shall be 
started at a certain charging 
rate, say, 10 amperes. The 
charging rheostat is manipu- 
lated until the ammeter ehows 
that the amount of current in 
question is going into the bat- 
teries. Figs. 49 and 50 show 
two forms of charging rheo- 
stats. This rate is maintained 

Fig. 60. Typical Charging Rheostat .»* ,1 1, , • i» 

until the voltmeter indicates 
that a certain potential has been reached, which is usually a voltage 
of about 2.55 volts per cell, measured with current flowing. The 
charging rate should then be reduced to 4 amperes, which causes a 
considerable drop in the battery voltage. This reduced charging 
rate is then maintained until the voltage again rises to the point 
at which the voltmeter stood when the current was reduced, i. e., 
until the voltage ceases to rise, which will generally be the same as 
the voltage at which the high rate of charge must be reduced. The 



335 



76 ELECTRIC AUTOMOBILES 

total voltage of the battery is usually taken as an indication, and 
when this fails to reach the desired figure, it is usually a symptom 
that some of the individual cells have defaulted. The remedy for 
this is given later. 

Precautions. At the end of both the starting and finishing 
periods, the cells will be gassing freely, i.e., giving off large quantities 
of hydrogen, and for this reason the battery space of the vehicle 
should be open and the room in which the charging is done should 
be well ventilated. In addition to being highly inflammable and 
explosive, this gas is also very irritant to the throat and lungs and 
when present in any quantity causes constant coughing. Nothing 
but electric light should ever be employed in a private garage used 
for the charging of an electric car. 

There are a number of other precautions to "be observed when 
placing the battery on charge in the vehicle besides that of providing 
ample ventilation, as already mentioned. The controller handle 
should be locked in the off position, the lamps switched off, and the 
bell should not be rung dujing the progress of the charge. The 
reason for the first of these precautions is self-evident and for the 
latter two is found in the increased voltage during the charge, and 
particularly as it approaches completion. This would be sufficient 
to cause the lamps to burn out and to injure the bell. It is important 
that the manufacturer's directions with regard to the charging rate 
be closely observed. In order to be certain that this is done, the 
current should be measured by an accurate ammeter mounted on a 
panel board in the garage. The ammeter on the vehicle should never 
be employed for this purpose, as the vibration and road shocks to 
w T hich it is subjected make the accuracy of such a delicate instrument 
a very uncertain quantity. 

Starting the Charge. To start charging, the rheostat handle 
should be turned so as to throw all the resistance in. The switch 
on the panel board should be open, and the charging plug should 
then be inserted in its receptacle on the car. These plugs are usually 
made so that they can be inserted only in the proper way, and there 
is no danger of reversing the polarity of the current in this manner. 
Where not thus designated, the terminals are properly marked and 
care must be taken to see that the plug is correctly inserted. When 
the plug is in, the switch may be thrown on. Battery manufacturers 

;j;$6 



ELECTRIC AUTOMOBILES 77 

supply tables showing what the starting and finishing voltages of 
the battery should be, as well as its final voltage; but as this will be 
influenced by varying conditions, such as the temperature of the 
battery and the age of the plates, the figures given are only approxi- 
mate. Furthermore, a new battery will have a higher final voltage 
than an old one under the same temperature conditions, and both 
old and new cells will read higher with the temperature low than 
when it is comparatively high. In view of the foregoing, a fixed 
voltage cannot be considered as an accurate test in determining the 
completion of the charge. Instead, a maximum voltage will be 
found the only certain indication. This may be determined by 
noting when the voltage ceases to rise as the end of the charge 
approaches. 

When charging during the day, the progress of the charge should 
be noted at half-hour intervals, the current being cut off as soon 
as the voltage has stopped rising. One of the commonest ways of 
abusing a battery is to overcharge it. This is most often done under 
the impression that an increased mileage will result, doubtless on 
the theory that if a certain distance can be covered by the vehicle on 
a full battery, "cramming" it a bit should give as many more miles 
proportionately as the excess charge bears to the normal capacity. 
Needless to add, this is a fallacy. No additional mileage will result 
from excessive overcharging, and where this occurs it causes the 
plates to deteriorate and thus reduces instead of increases the dis- 
tance that may be covered. A direct indication of excessive over- 
charge takes the form of a noticeable increase in the temperature of 
the cells. 

The question of temperature during the charge has already been 
touched upon. This should not exceed 110° F., and when charging 
with the battery in the vehicle, as is usually done, the middle cells 
should be taken as a guide. Unless it cannot be avoided, it is prefer- 
able not to allow the cells to rise above 100° F., reducing the charging 
rate or stopping the charge altogether for a time if the temperature 
does reach this point. 

Automatic Charge-Stopping Device. Where constant attend- 
ance during charging is neither practicable nor desirable — as in the 
case of the owner who takes care of his own car — an automatic 
charge-stopping device is a great convenience. This is an attach- 

337 Digitized by G00gle 



78 



ELECTRIC AUTOMOBILES 



ment to the Sangamo ampere-hour meter, and is much used on 
such installations. It consists of a solenoid-actuated trip-circuit 
breaker, Fig. 51, which is 
set in operation by the 
pointer of the meter when 
closing a circuit on arriv- 
ing at the point of full 
charge, a point which has 
been fixed by the operator 
in advance. However, as 
it is necessary to put more 
current into a storage 
battery than can be 
obtained from it, a 
certain amount of over- 
charge must be allowed 
for in every case. The 
amount necessary will 
naturally depend upon 
the condition of the bat- 
tery as influenced by its 
age and the treatment it 
has received, but it can 
be determined readily after a little experience. In the Sangamo 
differential shunt ampere-hour me ter referred to, a sliding adjust- 
ment is provided for this purpose and, once set, it need net be 
_ disturbed for a consid- 

J| x^i liX erable period unless 

made necessary by a 
change in the condition 
of the battery. With 
this adjustment made, 
the charging can be done 
by any unskilled laborer, 
as it is only necessary to 
make the charging con- 
nection and leave it. 
Since the circuit cannot 



Fig. 51. Solenoid- Actuated Trip Circuit Breaker 

Courtesy of Sangamo Electric Company, 

Springfield, Illinois 




To Battery 



To Load 



FiK. 52. 



Circuit Diagram of Charge-Stopping Device, 
Sangamo Amr^^e-Hour Meter 



338 



Digitized by 



Google 



ELECTRIC AUTOMOBILES 

TABLE 111 
Temperature Correction for Specific Gravity of Electrolyte* 



79 



30° F. 


40° F. 


50° F 


60° F. 


70° F. 


80° F. 


90° F. 


100° F. 


1.317 


1.313 


1.310 


1.307 


1.303 


1.300 


1.297 


1.293 


.12 


.08 


.05 


.02 


1.298 


1.295 


92 


.88 


.07 


.03 


.00 


1.297 


.93 


.90 


.87 


.83 


.02 


1.298 


1.295 


.92 


.88 


.85 


.82 


.78 


1.297 


.93 


.90 


.87 


.83 


.80 


.77 


.73 


.92 


.88 


.85 


.82 


.78 


.75 


.72 


.68 


.87 


.83 


.80 


.77 


.73 


.70 


.67 


.63 


.82 


.78 


.75 


.72 


.68 


.65 


.62 


.58 


.77 


.73 


.70 


.67 


.63 


.60 


.57 


.53 


.72 


.68 


.65 


.62 


.58 


.55 


.52 


.48 


.67 


.63 


.60 


.57 


.53 


.50 


.47 


.43 


.62 


.58 


.55 


.52 


.48 


.45 


.42 


.38 


.57 


.53 


.50 


.47 


.43 


.40 


.37 


.33 


.52 


.48 


.45 


.42 


.38 


.35 


.32 


.28 


.47 


.43 


.40 


.37 


.33 


.30 


.27 


.23 


.42 


.38 


.35 


.32 


.28 


.25 


.22 


.18 


.37 


.33 


.30 


.27 


.23 


.20 


.17 


.13 


.32 


.28 


.25 


.22 


.18 


.15 


.12 


.08 


.27 


.23 


.20 


.17 


.13 


.10 


.07 


1.203 


.22 


.18 


.15 


.12 


.08 


.05 


1.202 


.98 


.17 


.13 


.10 


.07 


1.203 


1.200 


.97 


.93 


.12 


.08 


.05 


1.202 


.98 


.95 


.92 


.88 


.07 


1.203 


1.200 


.97 


.93 


.90 


.87 


.83 


1.202 


.98 


.95 


.92 


.88 


.85 


.82 


.78 


.97 


.93 


.90 


.87 


.83 


.80 


.77 


.73 


.92 


.88 


.85 


.82 


.78 


.75 


.72 


.68 


.87 


.83 


.80 


.77 


.73 


.70 


.67 


.63 


.82 . 


.78 


.75 


.72 


.68 


.65 


.62 


.58 


.77 


.73 


.70 


.67 


.63 


.60 


.57 


.53 


.72 


.68 


.65 


.62 


.58 


.55 


.52 


.48 


1.167 


1.163 


1.160 


1.157 


1.153 


1.150 


1.147 


1.143 



♦Gushing and Smith, Electric Vehicle Handbook. 

be broken until the predetermined number of ampere hours have 
been absorbed by the battery, the latter will remain connected to 
the mains until fully charged, so that there is no danger of either 
undercharging or overcharging, as may occur where the charge is 
simply limited by the time considered necessary. The circuit of 
this charge-stopping device is shown by the diagram, Fig. 52. The 
circuit breaker also opens the exciting circuit, so that it carries the 
current only for an instant. 

Rated specific gravity for various stages of charge is based on 
a temperature of 80° F. Corrections for temperatures above and 
below this point may be made from Table III. 

Testing Progress of Charge. Upon the completion of the charge, 
the rheostat handle should always be turned back before opening 



339 



Digitized by 



Google 



80 ELECTRIC AUTOMOBILES 

the battery switch. It is essential that any voltage readings taken 
as a guide of the battery's condition should be noted only while the 
charging current is on. This applies likewise 
to readings during the discharge of the bat- 
tery, which should be taken while the vehicle 
is running, as the voltage with the battery 
standing idle is of no value as an indication 
of its condition. 

But the voltage alone must not be de- 
pended upon. The specific gravity of the elec- 
trolyte as well as the voltage will rise and 
reach a maximum as the end of the charge 
approaches. Specific gravity readings should 
therefore be taken with the hydrometer syringe 
provided for this purpose. This instrument 
consists of a glass syringe in which there is a 
hydrometer, Fig. 53. By inserting the point 
of the syringe in the venthole of a battery, 
it may be filled with the electrolyte, thus 
causing the hydrometer to float. The specific 
gravity of the solution may be noted and the 
latter replaced in the cell without any neces- 
sity for handling. Several cells in various Fi(? M 8yringe Hydrojn . 
parts of the battery should thus be tested as eter«et 



Fig. 53. Acid Testing Set in Separate Parts 
340 



Google 



Digitized by VjOOQ 



ELECTRIC AUTOMOBILES 



81 



TABLE IV 
Baume Scale of Specific Gravities 



Baume 


Specific Gravity 


Baume 


Specific Gravity 





1.000 


18 


1.141 


1 


1.006 


19 


1.150 


2 


1.014 


20 


1.160 


3 


1.021 


21 


1.169 


4 


1.028 


22 


1.178 


5 


1.035 


23 


1.188 


6 


1.043 


24 


1.198 


7 


1.050 


25 


1.208 


8 


1.058 


26 


1.218 


9 


1.066 


27 


1.228 


10 


1.074 


28 


1.239 


11 


1.082 


29 


1.250 


12 


1.090 


30 


1.260 


13 


1.098 


31 


1.271 


14 


1.106 


32 


1.283 


15 


1.115 


33 


1.294 


16 


1.124 


34 


1.306 


17 


1.132 


35 


1.318 



a check of the voltage. An older form of testing set is shown in 
Fig. 54. When fully charged, the specific gravity of the electrolyte 
should be between 1.270 and 1.280. Because of the spraying 
through the ventholes when the cells are gassing freely, and the 
loss by stoppage and evaporation, there is a gradual lowering of 
the specific gravity. It may be permitted to run as low as 1.250 
when fully charged. It is not necessary to make both the voltage 
and specific gravity tests every time the battery is charged, but 
they should be carried out at least once a fortnight, when all the 
cells should be tested to determine if they are in uniform condition. 
Baumt Scale. Hydrometers are often graduated according to 
the Baum6 scale. The Baum6 scale for liquids heavier than water 
is based upon the following equation : 

145 — Baume degrees 

Table IV gives the corresponding specific gravities and Baume 
degrees. 

Should the specific gravity of some of the cells be lower than 
the remainder of the battery, the low cells should first be charged 
separately at a low rate. If the specific gravity increases, it is an 
indication that the cell had been discharged to a lower point than the 



341 



Digitized by 



Google 



82 ELECTRIC AUTOMOBILES 

others and simply needed additional charging. Should this not be 
the case, and if neither the specific gravity increases nor the tem- 
perature rises rapidly during the charge, it indicates that the gravity 
of the electrolyte has been lowered by the addition of water to com- 
pensate for loss due to leakage or similar cause. The cell should 
accordingly be examined for the cause of the loss by sawing through 
the connections or straps and removing the cell from the battery. 
If the jar is found to be broken or cracked, a new one should be 
substituted, new electrolyte of the same specific gravity as that of 
the remaining cells put in, and the cell fully charged. The specific 
gravity of the electrolyte should then correspond with that in the 
other cells. If the loss of electrolyte has been due merely to slopping 
over, electrolyte should be added and the whole tested for the right 
specific gravity. The outside of the jar and the tray beneath it should 
be thoroughly cleaned, and the cell put back and its connections 
burned into place, care of course being taken to have positive and 
negative plates connected as they were before removal. 

As the electrolyte of the Edison cell does not vary with its 
state of charge, the specific gravity test cannot be employed, the 
voltmeter affording an accurate indication of the condition of the 
cells. Electrolyte cannot be lost from the Edison cell as it is sealed 
in, but there is a certain amount of loss by evaporation which must 
be replaced with distilled water. 

Electrolyte. Manufacturers of storage batteries usually recom- 
mend that small users purchase their supplies of electrolyte from them 
in order to be certain of its purity and specific gravity. Where this 
is not convenient, the owner of the electric vehicle may mix his own 
solution. This should consist of distilled water and pure sulphuric 
acid in the proportion by volume of one part acid to four and three- 
quarter parts of water for electrolyte of 1.200 specific gravity, or one 
part acid to three of water for 1.275. A glass, porcelain, or earthen- 
ware vessel must be employed for mixing the solution, and the acid 
must be poured very slowly into the water. Never pour water into 
acid, for while the effect of slowly adding acid to water is negligible, 
the adding of water to concentrated acid is accompanied by violent 
chemical action and an evolution of heat will usually break the 
containing vessel and always cause a dangerous spattering of the 
acid. 



,Goo 9 Ie 



Digitized by VjOOQI 



ELECTRIC AUTOMOBILES 83 

The sulphuric acid should be chemically pure, and, wherever 
possible, distilled water should be used. If this is not obtainable, 
the use of clean rain water is recommended as being likely to contain 
less impurities than any other. The keeping of the electrolyte free 
from impurities is a matter of the utmost importance and one that 
must ever be borne in mind. All dirt and foreign substances, both 
liquid and solid, must be rigidly excluded. A piece of iron in the 
shape of a stray tack, small nut, or wire may fall into a cell and ruin 
it before its presence is discovered. The presence of iron will be 
indicated by the electrolyte and the positive plate becoming a 
dirty yellow color. Some other impurities also make their presence 
readily known, for instance, chlorine will give off fumes that are 
easily recognizable by their disagreeable odor. 

Whenever such a condition is discovered, the only remedy is to 
dismantle the cell immediately, regardless of the state of charge or 
discharge it may be in. Discard the electrolyte and the wood separa- 
tors, and thoroughly rinse in running water all parts of the cell, 
such as the jar, rubber separators, and both of the elements; the 
latter should be washed separately. Reassemble with new electro- 
lyte of the same specific gravity as that discarded, and new wood 
separators. Charge the cell and discharge fully several times. 
After the last of these discharges and before recharging, take the 
cell apart a second time, again discarding the electrolyte, rinsing 
the parts of the cell in running water and soaking the wood separators 
in several changes of water. The cell may now be reassembled 
permanently with electrolyte of 1.200 specific gravity. It should 
be given a long charge before being put into service again. Care 
must be taken not to allow the negative elements to become dry 
at any time dining this operation, in fact, it is better to keep both 
sets of plates under water until reassembled. 

Dangers of Overcharging. To revert to the subject of charging 
in general, too much cannot be said regarding the evils of giving an 
excessive overcharge, an abuse which may occur in two ways: charg- 
ing the battery for too long a time, and charging too frequently. 
The commoner of these — that of charging too long a time — is easy 
to avoid. The other is not so apparent, and is the result of a practice 
which is apt to be indulged in by the uninitiated owner of an 
electric car, being due to a desire to have it always ready to run 

343 



84 ELECTRIC AUTOMOBILES 

its available mileage. This is the custom of charging too frequently. 
For instance, if the capacity of the battery will run the car 40 miles 
on a charge, and but 5 miles are covered and a short charge given, 
then 10 miles are covered, and a second charge, followed by a second 
and third installment of 10 miles with a charge between each and 
after the last, it is obvious that but 35 miles have been covered 
altogether, but the battery has been charged four times. This is 
three times more than was necessary under the circumstances, 
besides which the available radius was not covered, so that the 
battery would really not have been discharged had the entire dis- 
tance in question been covered without recharging. The greatest 
wear on the plates of a battery occurs during the final part of a 
charge, so that the oftener the battery is charged the shorter its life 
will be. As stated at the outset, the life of the very best cell made 
is measured by a certain number of discharges, but this is on the 
assumption that it is not recharged until actually discharged each 
time. Where a vehicle is employed for short runs, such as those 
mentioned, the capacity of the battery will not give as great a 
mileage as if the entire distance were covered in one run. When 
covering but a few miles in daily service, it is not advisable to 
recharge until between 50 and 75 per cent of its capacity has been 
exhausted. 

Where it is desired to use the car within a comparatively short 
time after the battery has been exhausted, it is permissible to hurry 
the charge within certain limits by using a higher rate than normal. 
This should be employed only at the start of the charge and 
should be reduced immediately the cells begin to,"gas." When the 
"finishing" voltage has been reached, the charge should be reduced 
to the normal starting charge, the remainder of the charge being 
carried out as if the battery had been started on the latter. Great 
injury may be done to the plates by "pounding" a nearly full battery 
at a high rate of charge. The foregoing precautions do not apply 
to the Edison cell. 

Time Required to Charge. The time required for charging will 
naturally depend upon the extent of the preceding discharge. If the 
latter has been two-thirds of the rated capacity of the battery, the 
usual pleasure car will require about three hours at the starting rate 
and one and a half to two hours at the finishing rate. In other words, 

344 



ELECTRIC AUTOMOBILES 



85 



about 10 to 15 per cent in excess of the amount discharged is usual. 
At least once a rbrtnight, a prolonged change should be given by 
continuing the charge for one hour after the specific gravity of the 
electrolyte has ceased to rise. Where a vehicle is maintained by its 
owner in a small private garage, and is used more or less during the 
day, it will be found a great convenience to do most of the charging 
during the night, and for this purpose the mercury arc rectifier, 
described in the chapter on "Methods of Charging", will be found 
a great help. Where direct-current service is available at 110, 220, 
or 500 volts, such an adjunct will naturally not be necessary. In 
over-night charging, precautions must be observed to prevent an 
excessive overcharge. To do this, a careful estimate of the current 
required to fully charge the battery must be made before putting it 
on charge, and the rate adjusted accordingly. If 12 hours be avail- 
able for charging and 84 ampere hours are necessary, the average 
rate of charge must be 7 amperes. Should the time be only 9 hours, 
as where a vehicle has been used in the evening and is wanted again 
early in the morning, the average rate would be slightly more than 
9 amperes. Where 72 ampere hours are required in 9 hours, the rate 
would be 8 amperes, and so on. The rate, however, will also depend 
to some extent on the voltage of the charging circuit, in charging 
from a source with constant voltage, the rate into the battery 
will fall as the charge progresses. This is also the case where the 
charging is done with the aid of a mercury arc rectifier. After the 
charge is ended, the voltage will drop immediately when the battery 
is disconnected. 

Charging an Edison Battery. The charging rates of Edison 
cells are based on a voltage of 1.85 volts per cell, so that the potential 
required to charge a battery of this type is as follows: 



Number of Cells 


Volts Across Cells 


10 


18.5 


20 


37.0 


30 


55.5 


40 


74.0 


50 


92.5 


60 


111.0 


70 


130.0 


80 


148.0 


90 


167.0 


100 


185.0 



345 



Digitized. by V 



Google 



86 



ELECTRIC AUTOMOBILES 



These voltages are just sufficient to charge the number of cells 
in question at the normal rate during the end of the chapge, as the 
alkaline cell increases its voltage during charge in the same manner 
as the lead cell, there being also a similar drop in voltage when the 
charging current is shut off. While a slight reduction in voltage 
from the potentials given will not materially affect the charge, 
allowance should be made for what is required in every case, if neces- 
sary, by charging the battery in series multiple. 

Owing to their construction the Edison cells are capable of being 
boosted at high rates when it is necessary to charge quickly, but the 
temperature must not be allowed to exceed 115° F. The following 
are the boosting rates recommended by the makers as the result of 

experience: 

5 minutes at 5 times the normal rate 
15 minutes at 4 times the normal rate 
30 minutes at 3 times the normal rate 
60 minutes at 2 times the normal rate 

The sizes, capacities, charge and discharge rates of the Edison 
cells are as follows: 



Type A-4 


A-5 


A-6 


A-S 


A-10 


A-12 


Capacity 150. ampere hours . 
Normal charge \»q 
Normal discharge J 

i 


187.5 
37.5 


225 
45 


300 
CO 


375 

75 


450 1 
90 



They are capable of discharge rates in excess of these figures in 
the same proportion as the boosting rates. 

BOOSTING 

Advantages of Boosting. The term "boosting" as applied to 
electric-vehicle batteries may be defined as "auxiliary charging", and 
must not be confused with its use in connection with the charging of 
large stationary batteries. As the lead-plate cell becomes com- 
pletely charged, its voltage rises to 2.5 volts per cell, which for the 
55 cells required to deliver current at 110 volts/would mean a poten- 
tial of 137.5 volts, or an increase of more than 20 per cent over that 
of the generator. The latter, not only being a constant potential 
dynamo, but also being called upon to deliver current for other 
service while charging the battery, it is necessary to raise the voltage 



346 



Digitized by 



Google 



ELECTRIC AUTOMOBILES 87 

of the charging current in order that it may exceed that of the 
battery without, at the same time, altering the output of the gen- 
erator. For this purpose, what is known as a "booster" is 
employed, i.e., a motor-generator which imposes a higher voltage 
on the charging current than that at which it is produced by the 
main generator. 

In the case of a vehicle battery, it usually implies a partial 
charge given in a comparatively short time and at current rates 
considerably higher than normal, and it represents a practice 
which has had an important influence on the use of the electric 
vehicle for commercial purposes. For example, many of New 
York's several thousand electric trucks of three to five tons' 
capacity are now sent on trips that were considered beyond the 
range of the electric only a few years ago, as it is not unusual for 
five-ton brewery trucks to make a fifty-to-sixty-mile day's run in 
one round trip from the plant. How this is accomplished with 
batteries whose normal output only suffices to run the car forty 
miles on a charge will be apparent from a consideration of the 
practice of "boosting" the battery, which is usually carried out 
during the noon hour. 

Regulation of Boosting Charge. Stress has already been laid 
on the fact that overcharging at high rates is injurious to the lead 
battery, and is the one thing to be most carefully avoided. How- 
ever, the improved forms of vehicle batteries now in use have con- 
siderable ability to absorb current at high rates under proper 
conditions. The only factors which act injuriously in high-rate 
charging are gassing and heating, and these appear only when the 
battery is receiving more current than the plates can utilize. 
Therefore, any current rate which the cells will absorb without 
gassing is not injurious, and it is upon this principle that boosting 
is applied. 

Possible Safe Charging Rates. The more nearly discharged a 
battery is the higher charging rate it can take, and by starting the 
charge at a high rate and tapering to a low rate at the end, a 
large proportion of the discharge can be replaced in a very short 
time. Table V gives the additional battery capacity which can be 
obtained by constant potential boosts with the battery in different 
states of discharge. 

347 ( Digitized by G00gle 



88 



ELECTRIC AUTOMOBILES 



TABLE V 
Potential Boosts at Different States of Discharge 



Battery Chabqb 


20-MlNUTE 

Boost 
Increase 


40-MlNUTE 

Boost 
Increase 


60-MlNUTB 

Boost 
Increase 


Battery fully discharged 


22% 
19% 
15% 
10% 


38% 
33% 
26% 
16% 


50% 

42% 
32% 
20% 


Battery three-quarters discharged 


Battery one-half discharged 


Battery one-quarter discharged 







Expressed in terms of mileage, this would mean that a car, 
after having given forty miles on a complete discharge, could have 
its battery boosted as follows: 

In 20 minutes so as to give 9 miles additional 
In 40 minutes so as to give 15 miles additional 
In 60 minutes so as to^give 20 miles additional 

Thus, by charging during the noon hour, 140 per cent of the 
battery capacity is obtained in one day, bad weather conditions 
particularly representing conditions under w r hich it is advantageous 
to be able to boost the battery. 

Methods of Boosting. There are several methods by which 
boosting can be practically carried out, and the method chosen 
depends upon the available charging facilities. 

Constant- Potential Method. The ordinary incandescent lighting 
circuit is supplied by a constant-potential generator, i.e., the volt- 
age does not vary regardless of the current utilized within the 
limits of the capacity of the generator. Where conditions permit, 
this is the best method because it is entirely automatic and 
requires little attention. It is applicable wherever there is avail- 
able a voltage of about 2.3 volts per cell of battery — say 110 volts 
for 48 cells — and the charging equipment and wiring have sufficient 
"capacity to carry current up to four or five times the usual charg- 
ing rate. A voltage higher than 2.3 volts per cell can be reduced 
by having a set of counter-e.m.f. cells figured at 3 volts per cell, 
which are always put in series with the battery w T hen it is boosted. 
This is a special type of cell designed for this purpose. Thus if the 
line voltage is 110 and the battery consists of 40 cells, a reduction 
of 18 volts will be necessary, and six of the counter-e.m.f. cells will 
be required. 



34£ 



' Digitized by 



Google 



ELECTRIC AUTOMOBILES 



89 



With the charging voltage thus fixed a,t 2.3 volts per cell, a 
battery in any state of discharge can be put on charge and will 
receive in a short time a large proportion of the discharge which 
has been utilized. The current input will taper automatically 
from a high rate at the start to a low rate at the finish, and no 
attention or adjustment is required. The cells will not reach the 
free gassing point or, under normal conditions, a high temperature 
and, therefore, no harm will result from their being inadvertently 
left on charge. 

Approximate Constant- Potential Method. This is employed 
with a fixed resistance in series with the battery; and when the 
time available for boosting is one hour or less, the following 
method is often the simplest. Connect a rheostat in ^eries with 
the battery and adjust the resistance so that the voltage across 
the battery terminals corresponds to that given as follows for the 
approximate number of cells. 



Number of Cells 


Voltage at Battery 
Terminals 


48 
44 
42 
40 
38 


110 

98 
92 
86 
80 



The circuit can then be left without attention for an hour or 
so, and the current will taper off as the voltage of the battery 

rises. The table is figured for a line voltage of , and the volt- 
ages given are too high for a boost of more than one hour's duration. 
Constant-Current Method. In some cases it is more convenient 
to boost at a constant rate of current, and, as there is usually a 
limited time available, it is desirable to know under any given condi- 
tions what rate is safe. This may easily be determined as follows: 

ampere hours already discharged 

Charging current (amperes) =7—7: .. , . ■ — : ~. — : 

1 + (hours available for boosting) 

This gives the maximum current which can be employed for the 

time specified without the cells reaching the gassing point. The 

method is most conveniently employed where the car is equipped 

with an ampere-hour meter. For example, 100 ampere hours have 



349 



Digitized by 



Google 



90 



ELECTRIC AUTOMOBILES 

TABLE VI 
Boosting Rates* 



AlCPEBS 

Hours 


Tims Available fob Boosting 


}i hour 


Yx hour 


% hour 


1 hour 


\\i hours 


1H hours 


\\i hours 


2 hours 


DlSCHABQBD 


















Amperes 


Amperes 


Amperes 


Amperea 


Amperes 


Ampere3 


Amperes 


Amperes 


10 


8 


6 


5 


5 


4 


4 


3 


3 


20 


16 


13 


11 


10 


9 


8 


7 


6 


30 


24 


20 


17 


15 


13 


12 


11 


10 


40 


32 


26 


23 


20 


18 


16 


14 


13 


50 


40 


33 


28 


25 


22 


20 


18 


16 


60 


48 


40 


34 


30 


26 


24 


22 


20 


70 


.56 


46 


40 


35 


31 


28 


25 


23 


80 


64 


53 


45 


40 


35 


32 


29 


27 


90 


72 


60 


51 


45 


40 


36 


33 


30 


100 


80 


66 


57 


50 


44 


40 


36 


33 


110 


88 


73 


63 


55 


49 


44 


40 


37 


120 


96 


80 


68 


60 


53 


48 


43 


40 


130 


104 


87 


74 


65 


58 


52 


47 


43 


140 


112 


93 


80 


70 


62 


53 


51 


47 


150 


120 


100 


86 


75 


67 


60 


54 


50 


160 


128 


106 


91 


80 


71 


61 


58 


53 


170 


136 


113 


97 


85 


75 


63 


62 


57 


180 


144 


120 


103 


90 


80 


72 


65 


60 


190 


152 


127 


108 


95 


84 


76 


69 


63 


200 


160 


133 


114 


100 


89 


80 


73 


67 


210 


168 


140 


120 


105 


93 


84 


76 


70 


220 


176 


147 


126 


110 


98 


88 


80 


73 


230 


184 


153 


131 


115 


102 


92 


84 


77 


240 


192 


160 


137 


120 


106 


96 


87 


80 


250 


200 


167 


143 


125 


111 


100 


91 


83 



♦Courtesy of Electric Storago Battery Company. 

Explanation. In the left-hand column find the figure nearest to the 
ampere hours discharged from the battery; follow across to the column headed 
by the available time. The figure at this intersection is the current to be used. 

Example.- Ampere-hour meter reading, 103 ampere hours discharged; 
time available for boosting, one hour. Start at 100 in the left-hand column; 
follow across to the column headed 1 hour and find 50, which is the current to be 
used. 

been discharged and there is one hour available for boosting. Then 

_ . 100 

Charging current = —- = 50 amperes 

In general, this method will not put in* as much charge in a 
given time as the constant-potential method, and the current must 
not be continued beyond the time for which the rate is figured, as 
injurious gassing and heating will result. When a considerable 



350 



Digitized by 



Google 



ELECTRIC AUTOMOBILES 91 

period is available for boosting, and it is convenient to regulate 
the current at intervals, a greater amount of charge is possible by 
dividing the time into several periods and regulating the amount 
of current for each period separately. It will usually be found 
that one of the methods outlined will be available, but to obtain 
the advantages of boosting without injury to the battery, gassing 
must be avoided and the temperature of the cells kept below 
110° F. 

Table VI is based upon the above formula and saves the 
necessity of making calculations. 

CARfe OF BATTERY 

Importance cf Careful Attention to Battery. The battery is 
naturally the chief factor in any electric automobile and, as its 
initial cost is no small fraction of the'total cost of the vehicle, its 
proper maintenance is a matter of economy no less than of good 
service. More so than any other piece of electrical apparatus, a 
storage battery has a definitely determined life. Regardless of the 
care given it, the active period of service of which it is capable 
may be expressed as a certain number of discharges. By properly 
looking after it, this number may be realized, and a greater per- 
centage of the energy put into it taken advantage of. In other 
words, its life will not only be longer, but its efficiency much 
higher during that period as the result of proper care. 

Limits of Discharge. To obtain the best possible service from 
a battery, it should never be discharged below 1.70 volts per cell, 
this being measured when the vehicle is running at full speed on 
the level, all of the cells then being connected in series. If the 
average discharge rate is for any reason considerably more than 
the normal rate of the battery, the working voltage will be cor- 
respondingly lowered, so that a slightly lower limiting voltage is 
permissible. In general, however, it is safer not to go below 1.70 
volts per cell, except momentarily, as when starting or on a grade. 
The battery should never be allowed to stand fully discharged, as 
local action and sulphating rapidly take place. 

Sulphating. It has been pointed out in the introductory sec- 
tion of Part I that during each discharge both the positive and 
negative plates become covered with lead sulphate, but in tLe 

Digitized by VjOOQ IC 



92 ELECTRIC AUTOMOBILES 

normal use of the battery the sulphate is converted during the 
following charge to lead peroxide on the positive plate and spongy 
metallic lead on the negative. Should the battery be allowed to 
stand in a discharged state for any length of time, however, the 
lead sulphate on the plates will harden, causing what is usually 
termed "sulphating." When the battery is put into use again this 
will result in loss of capacity, buckling, shedding of the active 
material from the positives, and greater heating of the cells due to 
increased internal resistance. Sulphating can be remedied by con- 
tinuous charging for a long period at a low rate, i.e., for 24 to 36 
hours, or longer, at a rate not exceeding 10 to 15 per cent of 
normal. This loosens the sulphate and reconverts it, thus restoring 
the plates. to their normal condition. The great loss of capacity, 
with the possible total ruin of the battery if sulphating is allowed 
to go on long enough, explains the emphasis laid on the instruc- 
tions — never let the lead-plate battery stand discharged. 

When it is not convenient to have the battery fully charged at 
once, a partial charge should be given and completed as soon 
thereafter as possible, and before the battery is again discharged. 
When the vehicle is out of service, the battery should be given a 
freshening charge at least every month, and every two weeks 
would be preferable. 

As an additional indication of the relative condition of the 
cells in a battery, the voltage of each cell should be taken with a 
low-reading voltmeter — i.e., one calibrated to read to 3 volts by 
tenths — at least once every two weeks, and the specific gravity of 
the electrolyte of each cell should also be tested at about the same 
interval. The voltage readings in question should be taken just 
before the end of the prolonged charge mentioned, or just before 
the end of a complete discharge, and always with the current flow- 
ing. Should any of the cells read lower than the average, it is an 
indication of trouble and they should be treated as explained later. 

Condition of the Cells. Electrolyte. One of the cardinal points 
to be observed in the care of the battery is to keep the plates covered 
with electrolyte to the depth of at least half an inch, but no more. 
Except where the level has been lowered by slopping or leaking, any 
loss should be replaced by the addition of distilled water, and should 
always be added at the beginning of a charge. 



.Google 



Digitized by VjOOQ I 



ELECTRIC AUTOMOBILES 93 

Connections. Attention should be paid to keeping the con- 
nections and terminals, the outside of the jars, the straps, battery 
trays, and the battery space in the vehicle dry and free from dirt 
and acid. This is a far more important precaution than may appear 
at first sight, for if not attended 
to, corrosion and loss of capacity 
will result. In storage batteries 
for starting and lighting gasoline 
cars, this difficulty has been ob- 
viated to a considerable extent 
by the use of a special form of 
cover incorporating an expansion 
chamber. 

CLEANINQ OR WASHING A 
BATTERY 

Methods of Avoiding Inju- 
rious Effect of Sediment in Cells. 

During the normal use of a bat- 
tery, the gradual wear of the 
plates results in a deposit of sedi- 
ment which collects in the bot- 
tom of the jar where a space is 
provided to hold a considerable 
quantity before it accumulates 
sufficiently to touch the bottom 
of the plates, Fig. 55. The rate 
at which sediment accumulates 
depends very largely upon 
whether the battery is charged 
properly or not. If the battery Fig 65 Elba Cell ^ Low Mud Space 

is Charged in SUCh a Way as tO and Bolted Connections 

cause excessive gassing, the gas coming out of the pores of the positive 
plates tends to soften and dislodge the active material. This is the 
reason the charging current must be reduced as soon as the cells 
begin to gas freely. If a battery is constantly undercharged, the 
sulphate which is thus allowed to accumulate in the negative plates 
will eventually lose its cohesion and the surface will gradually wash 



, Google 



Digitized by UOOQ I 



94 ELECTRIC AUTOMOBILES 

away, falling to the bottom of the jar as a deposit of sediment. It 
is neither necessary nor desirable that every charge be carried to com- 
pletion, but in order to make certain that the plates do not become 
sulphated, a weekly "equalizing" charge is given. 

If a battery has been neglected so that cleaning is not undertaken 
until the deposit of sediment has actually reached the plates, the 

sediment is then deposited much 
more rapidly. Permanent injury 
and decreased life of the plates 
result. The Elba cell, Fig. 56, is 
designed with a mud space suffi- 
ciently high to accommodate the 
entire deposit of sediment occur- 
ring during the life of the elements, 
so that washing is not necessary 
in this type of cell, tlje jars only 
being cleaned out when the ele- 
ments are renewed. 

Since the conditions under 
which batteries are operated vary 
so widely, the best method of 
determining when it will be nec- 
essary to clean a battery is to 
remove the element from one of 
the cells after about 100 to 150 
charges have been given it, to 
determine the rate at which the 
sediment is accumulating. From 
the amount of sediment compared 
with the depth of the space in the 
bottom of the jar, it is possible 
to estimate when cleaning will 

Fig. 56. Elba Cell with High Mud Space . . . . 7 , 

be required. Always clean a 
battery before there is any possibility of the sediment reaching the 
bottoms of the plates. To insure this, the entire depth of the space 
should not be taken as a fixed quantity in estimating the rate of 
sediment deposit, but a margin of safety of \ to f inch should be 
allowed, since the jolting of the vehicle is apt to bring the sediment in 

Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 95 

contact with the plates and short-circuit them momentarily, if allowed 
to rise any closer. At the expiration of the estimated time, cut out a 
different cell and examine it to determine definitely if the time for 
cleaning has arrived* 

Various Conditions to be Found. The method of procedure in 
<: eaning will depend upon the condition of the battery, as follows: 

1. If the battery has not been allowed to become sulphated and the sediment 
has not reached the bottoms of the plates, its cleaning is a comparatively simple 
operation and the only preliminary treatment is to first bring the battery to a 
state of full charge. . 

2. If the battery is in a sulphated condition due to improper charging, 
but the sediment has not reached the bottoms of the plates, it should be given 
the treatment detailed under "Restoring a Sulphated Battery", before cleaning. 

3. If the sediment has been allowed to reach the bottoms of the plates 
because cleaning was not carried out soon enough, the battery will, as a matter 
of course, be in a sulphated condition by reason of the short-circuits through the 
sediment. Such a battery must first be cleaned as described below and after- 
ward given the treatment referred to under "Restoring a Sulphated Battery". 
This treatment cannot be given successfully in its short-circuited condition. 

Materials to Have on Hand. Before starting the work of clean- 
ing the battery, have on hand a set of new wood separators and suffi- 
cient new acid of 1.300 specific gravity with which to mix new elec- 
trolyte. Many of the old rubber separators can be used again, but, 
as is the case when renewing the entire element of the cell, about 
twenty-five per cent of new rubber separators should be at hand for 
replacements. Three or four extra jars and covers should also be at 
hand, and the trays should be examined to note if their condition is 
such that they may be depended upon to last the remaining life of the 
cells. If new trays are necessary, see instructions under "Renewal". 

In fact, as the process of cleaning is, to a large extent, the same as 
that of renewing the elements, the instructions for dismantling the 
battery are the same. All the connectors should be removed by 
pulling or drilling. The jar covers should be lifted by running a hot 
putty knife around their edges, and the covers should be washed in 
hot water and then stacked one on top of the other with a heavy 
weight on them to press them flat. 

Treating the Plates. Lift all the jars out of the trays, leaving 
their elements in the electrolyte. The trays can then be examined, 
and, if usable, given the treatment described in connection with 
renewals to neutralize any acid in the wood. Proceeding further, 

355 Digitized by GoOgk 



96 ELECTRIC AUTOMOBILES 

one cell should be treated at a time. The element is pulled out with 
the aid of pliers, meanwhile holding the jar with the feet; it is laid on 
the bench and the plates spread slightly to permit of removing the 
separators, taking care not to injure the rubber sheets, Fig. 57. 
Separate the positive group from the negative. If the active material 
of the negative be swollen beyond the surface of the grid, press it back 
into position before it has a chance to dry by placing boards of suit- 
able thickness between the plates and carefully squeezing the group 
between heavy boards in a vise or press, as shown in Fig. 58. Boards 
of sufficient size and thickness must be used between the plates or 



Fig. 57. Removing Old Separators from 

Elements Fig. 58. Pressing Negative Group 

Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania 

breakage will result. Charged negative plates, when exposed to the 
air, will become hot in a short time and in this event should be allowed 
to cool before reassembling. Remove any loose particles adhering 
to the positive plates by passing a smooth wooden paddle over the 
surface, but do not wash the positive plates. 

Washing or Renewing Separators and Assembling Cells. Wash 
all the sediment out of the jar to have it ready for the element when 
reassembled. Wash and save the rubber sheets, but throw away 
the old wood separators. "Wash" in this connection means to place 
under running water that is known not to contain any injurious 
impurities, for fifteen minutes or more. Reassemble the positive 



350 



ELECTRIC AUTOMOBILES 97 

and negative groups with the plates on edge in order to insert the 
separators. Place a rubber separator against the grooved side of a 
wood separator, Fig. 59, and insert a positive plate near the center of 
the element. The rubber sheet must be against the positive plate 
and the wood separator against the negative plate. In this manner, 
insert separators in all the spaces, working in both directions from 
the center, exactly the same as in renewing the element. An omitted 
separator means a short-circuited cell. 

The separators should be practically flush with the bottoms of 
the plates to bring their tops against the hold-down below the strap, 
and must extend to, or beyond, the 
side edges of the plates. Grip the 
element near the bottom to prevent 
the plates from flaring out while 
placing in the jar. Fill the cell to 
within \ inch of the top of the jar, 
using electrolyte of a specific grav- 
ity of 1.250, unless the battery is 
in a sulphated condition, in which 
case, use water. After all of the 
cells have been given the same treat- 
ment and reassembled, place them 
in the trays in the proper position, 
so that the 'positive of each will be 
connected to the negative of the adjoin- 
ing cell, and connect temporarily 
by pressing the old connectors into 

*^ " Fig. 59. Wood and Rubber Separator 

Charging Process after Wash- 
ing Battery. Put the battery on charge at the regular finishing rate 
and, after charging about fifteen minutes, note the voltage of each 
cell, recording these readings as mentioned in connection with renew- 
als. This is to insure the cells having been correctly connected with 
regard to their polarity. If this is the case, each cell should read 
above 2 volts; any cell with a lower reading is likely to have been con- 
nected backward. When the cells begin to gas freely and uniformly, 
take and record a hydrometer reading of each cell and the tempera- 
ture of one cell. Reduce the current to one-half the normal finishing 

357 



98 



ELECTRIC AUTOMOBILES 



^ 



rate. Should the temperature reach 100° F., reduce the charge or 
interrupt it temporarily so as to prevent the cells getting any hotter. 
Both hydrometer and temperature readings must be taken at regular 
intervals, say four to six hours apart, to determine if the specific 
gravity is still rising or if it has reached its maximum. Continue 
the charge and the readings until there has been no further rise in any 
cell during a period of at least twelve hours. Maintain the height 
of the electrolyte constant by adding water after each reading. (If 
water were added just before taking the reading, it would not have 
time to mix with the electrolyte, and the reading would be misleading.) 
Should the specific gravity rise above 1.300 in any cell, draw off 
its electrolyte down to the level of the top of the plates and refill with 
as much water as possible without overflowing. Continue the charge, 
and if the specific gravity again exceeds 1.300 all the electrolyte in 

that cell should be dumped 
out and replaced with 
water, then continue the 
charge. The charge can 
be considered complete 
only when there has been 
no rise in the gravity of 
any cell during a period 
of at least twelve hours of 
continuous charging. 
Upon completion of the charge, the specific gravity should be 
adjusted to its proper value (1.270 to 1.280), using water or 1.300 
acid as may be necessary, and the electrolyte level adjusted to a 
uniform height of J inch above the plates. 

Discharge the battery at its normal discharge rate (see 
"Renewal") to determine if there are any low cells caused by defective 
assembly, which should immediately be corrected. Recharge and 
then remove the temporary connectors. When the cells are arranged 
in their trays, as shown in the sketch made before the battery was 
taken apart, Fig. 60, put the rubber covers in place, wipe the inside 
edges of the jars dry, and seal with the compound supplied for this 
purpose. Heat the sealing compound, taking care that it is not 
allowed to burn, and apply around the edges of the cover, smoothing 
down with a hot putty knife. 



E. 



Fig. 60. Diagram of Battery Connections Drawn 
before Dismounting 



358 



Digitized by 



Google 



ELECTRIC AUTOMOBILES 99 

It is preferable to use new connectors, but if these have not been 
provided, the old ones may be replaced if sufficient care has been taken 
in removing them. Before putting the connectors in place, scrape 
the posts clean and smooth. In using' old connectors, clean out the 
eyes with a knife blade. When the connectors have been put in place, 
tap them down firmly to insure good contact. Before reburning the 
connectors in place, test each cell with a low-reading voltmeter to 
make certain that the cells have all been reconnected in the proper 
direction, i.e., that their polarity has not been reversed. It is not 
sufficient to note that the voltage of the cell is correct, i.e., 2 volts 
or over; but care must be taken also to note that it is in the right 
direction. With a voltmeter having a needle that can move in both 
directions from zero, v one polarity will be evidenced by the needle 
moving over the scale to the right of the neutral line, while if the 
polarity be reversed, the needle will move to the left, so that a cell 
having the proper polarity should be tested, and then, to be correct, 
all the remaining cells should cause the needle to move in the same 
direction and read to approximately the same voltage when the 
instrument leads are held to the cell terminals in the same way for 
each. Where the voltmeter needle can move only in one direction, 
i.e., to the right, a change of polarity will be indicated by the needle 
of the instrument attempting to move to the left and, in so doing, 
butting up against the stop provided to prevent this. 

Complete the reassembly of the battery by burning the connec- 
tors of all the cells together, detailed instructions for this being given 
under "Lead Burning , \ The cleaning of a battery which has been 
properly charged and in which the sediment has not been allowed to 
reach the bottoms of the plates is a simple operation compared with 
treatment necessary to clean and restore a battery which has been 
neglected. The process of cleaning is also frequently referred to as 
"washing the battery", which refers to the internal treatment 
already outlined, and not to washing it outside. 

It is of the utmost importance that the battery be cleaned before the 
sediment is allowed to accumulate to a point where it reaches the plates. 

Replacing a Defective Jar. When a cell requires the addition of 
distilled water more frequently than the other cells in the same bat- 
tery, or does not test to the same specific gravity as the others, it is 
usually an indication that there is a leak in the jar. Failure to give 

Digitized by VjOOQ IC 



100 ELECTRIC AUTOMOBILES 



Fig. 61. Drilling off Connectors 
Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania 



Fig. 62. Lifting Cell out of Tray 
Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania 



360 



Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 101 

the same gravity reading is not always proof of this condition, as the 

cell may be low from other causes, but the loss of electrolyte is certain 

evidence of it. The only remedy 

is to replace the jar at fault. 

While the following directions 

for doing this apply to the 

Exide battery in particular, they 

will be found equally applicable 

to all other makes. 

After locating the jar at fault, 
first mark its connectors so that there 
will be no mistake in replacing them 
the same way. With a i -inch bit or 
twist drill of the same size, drill the 

connectors centrally in the top of the Fi g . 63. Softening Sealing Compound on Cell 
enlarged ends joined to the two cells 

adjacent to the jar that is to be replaced, Fig. 61. Lift the complete cell out 
of the tray, Fig. 62, and with an ordinary gasoline blow torch warm the sides 
of the jar around the top to soften the 
sealing compound that holds the cover, 
Fig. 63. Grip the jar between the feet, take 
hold of the two connectors, and pull the ele- 
ment almost out of the jar, Fig. 64; then grip 
the element near the bottom in order to keep 
the plates from flaring out, Fig. 65, while trans- 
ferring to the new jar, taking care not to let 
the outside plates start down over the outside 
of the jar, Fig. 66. After the element is in the 
new jar, reseal the cell by pressing the sealing 
compound into place with a hot knife. Fill 
the cell with 1.250 electrolyte to the proper 
point, the old electrolyte being discarded. 

Before replacing the connector, clean 
both the post and the inside of the eye of the 
connector by scraping smooth with a knife. 
When the connector has been placed in posi- 
tion, tap it down firmly over the post to insure 
good contact. To complete the connection, 
melt the lead of the connector and the post at 
the top so that they will run together, and, 

while the lead is still molten, melt in more Fig. 64. Lifting Element out of Jar 
lead until the eye of the connector is filled, y 

Fig. 67. This is termed lead burning and is described at greater length in a 
succeeding section. Where no special facilities are at hand for carrying it out, 
it may be done with an ordinary soldering copper. The latter is brought to a 
red heat so that all the "tinning" is burned off and no flux of any kind is used. 



361 



Digitized by VjOOQ IC 



102 ELECTRIC AUTOMOBILES 



Fig. 65. Gripping Element near Bottom Fig. 66. Installing Element in Jars 

to Keep Plates from Flaring out 

Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania 



The method of handling the iron and the lead-burning strip to supply the extra 
metal required to fill the eye is shown in Fig. 68. 

Put the battery on charge, and when the cells begin to gas freely, reduce 
the current to half the " finishing' ' rate given on the battery name plate, and 



Fig. 67. Reburning Cell with Carbon Arc 
Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania 



362 



Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 103 

charge at this rate as long as there is any rise in gravity in the electrolyte in this 
or in any of the other cells. The maximum gravity has been reached when there 
has been no rise for a period of three hours. If the gravity of the cell having 
the new jar is then over 1.280, draw off some of the electrolyte and replace with 



Fi ;. 68. Reburning Cell with Soldering Iron After Replacements Previously 

Described Have Been Made 

Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania 

distilled water. If the gravity is below 1.270, draw off some of the electrolyte 
and replace with 1.300 electrolyte. If necessary to put in 1.300 electrolyte, allow 
the battery to continue charging for about one-half hour longer at a rate sufficient 
to cause gassing, which will cause the stronger acid to become thoroughly mixed 
with the rest of the electrolyte in the cell. 



COMPLETE RENEWAL OF BATTERY 

Materials Needed. In garages caring for a number of electric 
vehicles, it is customary to carry out all the repair work demanded by 
the batteries, including the complete renewal of the cells. The 



363 



104 ELECTRIC AUTOMOBILES 

material is ordered from the maker of the battery, and the form in 
which it is sent for will depend upon the facilities at hand. The 
following material is required for a complete renewal: positive 
groups, i.e., plates already burned to straps, or positive plates and 
positive straps, negative groups or negative plates and negative straps, 
connectors, burning strip, wood separators, rubber separators, rubber 
jars, rubber covers, rubber plugs, sealing compound, electrolyte, 
trays, handles, and terminals. 

Note the number of plates and their size and type, this informa- 
tion usually being given on the plate on the tray. Unless facilities 
are at hand for burning the plates into groups, it is better to order 
groups. If the plates are ordered loose, positive and negative straps 
must also be ordered, and, in any case, the following information must 
be given: size and type of plate, number of plates per cell, length of 
jar outside, width of jar outside, height of jar outside, height from top 
of rib of jar. In ordering connectors, give the distance between the 
center of the eyes, noting if more information than the size is 
required. Two pounds of burning strip is sufficient for burning the 
connectors of an ordinary battery; when loose plates are ordered, 
provide one pound additional for each fifty plates. The clippings 
from the plate lugs can be melted down and cast into strips for this 
purpose, if desired. 

Where the separator type cannot be identified by name or num- 
ber, send samples of the old ones to the manufacturer. All new 
wood separators will be necessary, and in ordering these it is advisable 
to provide at least 10 per cent more than are actually required. Most 
of the old rubber separators can be used again, but it is well to provide 
about 25 per cent of new ones. Order three or four extra jars and 
covers, giving the dimensions as already noted. A new set of rubber 
plugs will usually be found advisable. The average pleasure-car 
battery or that of a light truck requires about | pound of sealing 
compound per cell; this compound is supplied in 5-, 10-, and 30-pound 
tins. In dismantling the old battery, measure the amount of electro- 
lyte necessary in one cell to bring its level \ inch over the plates, and 
order sufficient 1.300 electrolyte to fill all the cells. Electrolyte is 
usually longer in transit than any other material, so this must be 
allowed for. In ordering new trays, make a sketch showing the 
inside and outside length, width, and depth, and whether the sides 

864 ^le 



ELECTRIC AUTOMOBILES 105 

are salid or slatted, also specify the size and type of handles and their 
position. When obtained locally, trays should be well painted with an 
acid-resisting paint. Upon receipt of the material, immediate atten- 
tion must be given the wood separators to prevent their drying out. 
Wood separators must always be kept wet 

Dismantling the Battery. To dismantle the old battery that is 
to be renewed, first remove all the connectors by drilling centrally in 
the top of the enlarged ends, as already explained in connection with 
the replacement of a jar. Where 
much of this work is done, a device 
termed a "connector puller ,, may be 
obtained from the battery maker. 
After removing the connectors, lift 
all the covers by running a hot 
putty knife around the sealed edges 
and, after they have been taken out, 
clean all the compound off them and 
place them in hot water. This will 
clean the acid from the covers and 
also soften them. In this condi- 
tion, stack the covers and place a 
weight on them to keep them flat. 

Lift all of the cells out of the 
trays. When making a complete 
renewal, the old trays are seldom 
worth saving, but if they are to be 
used again, immerse them in a barrel 
of water in which about 10 pounds 

Of bicarbonate Of Soda (common Fig. 69. Lifting Element out of Jar 

with Pliers 

baking soda) has been dissolved, 

to neutralize the acid in the wood. After drying, they will be 
ready for use. Grip one jar firmly between the feet and lift out 
the element with the aid of two pairs of pliers, Fig. 69. Spread 
the plates slightly and remove the wood and rubber separators, 
taking care not to injure the rubber sheets. Throw away the 
old wood separators and scrap the old plates. Wash all sedi- 
ment out of the jars to have them ready for assembling the new 
elements. 



365 Digitized by G00gk 



100 ELECTRIC AUTOMOBILES 

Burning Groups. When new plates and straps have been 
ordered separately and are to be burned into groups, first provide a 

"burning box", as shown in 
Fig. 70. Scrape the plate lugs 
clean and bright and arrange the 
plates as shown in the burning 
box. The height of this box 
should be J inch less than the dis- 
tance from the top of the ribs of 
the rubber jar to the top of the 
jar. The burning iron, which 
acts as a space between the plates 
and as a support for the strap, 
should be made of iron £ inch 
thick and slotted to fit the plate 
lugs. This | inch in addition to 
the height of the burning box 

Fig. 70. Assembling Group in Burning Box wi jj g j ye ^ r j ght he j ght for ^ 

strap, the bottom of which should be f inch below the top of the jar. 
Place the strap over the plate lugs to rest on the burning iron. 

The plate lugs should be trimmed about flush with the top of the strap. 

After burning, cut off the pro- 
jecting ends of the negative 
straps so that the elements may 
enter the jars, Fig. 71. It is not 
necessary to clip off the ends of 
the positive straps. 

Before dismantling the old 
battery, a sketch of the position 
and polarity of the cells in each 
tray should be made, indicating 
the position of the tray terminals 
and their polarity, that is, wheth- 
er the positive is to the right or 

Fig. 71. Clipping off End of Negative Strap left side ° f the tn V wh ™ facin & 

the terminal end, Fig. 60. 
Reassembling the Cells. Assemble the new positive and nega- 
tive groups with the plates on edge in order to insert the separators. 



366 



Digitized by VjOOQIC 



ELECTRIC AUTOMOBILES 107 

Place a rubber separator against the grooved side of a wood separator, 
Fig. 59, and insert between a positive and a negative plate near the 
center of the element. The rubber sheet must be against the positive 
and the smooth side of the wood separator against the negative, 
Fig. 72. In like manner, insert separators in all the spaces, working 
in both directions from the center. Leaving out a separator means a 
short-circuited cell. The separators should be practically flush with 
the bottom of the plates to bring their tops against the hold-down 
below the strap arid must extend to or beyond the side edges of the 
plates. Grip the element near the bottom in order to prevent the 
plates from flaring out when placing the element in the jar. 

Fill the cells to within \ inch of the top of the jars, using electro- 
lyte of a specific gravity of 1.300 and allow the cells to stand from 



Fig. 72. Installing Separators 
Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania 

twelve to twenty-four hours before starting to charge. After all the 
cells have been assembled, place them in trays in the proper position, 
so that the positive of each will be connected to the negative of the 
adjoining cell and connect temporarily by pressing the connectors into 
position by hand, using the old ones if available. 

Initial Charge* Give the initial charge by putting the battery 
on the regular finishing charge rate. After charging about thirty 
minutes, note the voltage of each cell, recording these readings as 
shown in the first column of the form, Fig. 73. 

This is, to insure that all the cells have been properly connected 
up, i.e., in the direction as to polarity. If they have been properly 

Digitized by VjOOQ IC 



106 ELECTRIC AUTOMOBILES 

connected, each cell will show in excess of 2 volts. Any cell showing 
less than 2 volts is probably connected backward and should be 
inspected. Then reduce the charging current to as near one-half of 
the regular finishing rate as the charging apparatus will permit. 
Select one cell near the center of the battery, which will be the 



<■• tw hmM* ertl mm ewer •» Uiwry* ifcUk jmwijr n*Hne» i«fc» **n *«• «•■) •""»» •• ft** »««■» "» ««■» vriuaa iM *• nattaMt MM 

rjKtKirt* ta plot Mil M k* tot4 ti MMorai bcl|M alwe-tair 1Mb «*•». plain »* •*»■«•■ «* *•"•««■• •»««• «■»» »■»•» •• *• •*•*> Mt»J»«i«MMJ 

Any vMitm«l im««c« «mMI caa be ant » Halt entaM*. •«**. W*»l«ri brfmr MM «• 
TlUilhrei Butt M COMKJtTBLT FILLED OCT. •*Wi«» fk«l lor bemf -MtlM. 
Dtacteict Mlowisf UtM ckMj m be fHMOcd m tack o# On *«<< 

•ATTERV FILLED WITH /2PP 3* ©r. .. «*"• ** — —Tyj* .. 2 &*- J? 1*1 ^ 

•attww .. «*»t dJL+ry. _ „. mo« .7-'<** ~4^s~£L*iStLjo-//j&2 tzJ*~'*-»^ 

Pilot Cell No. /£ l* I? 



Fig. 73. Specimen Battery Charging Record 
Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania 

"pilot cell" throughout the charge. Record readings of time and 
current and the specific gravity and temperature of this pilot cell, as 
indicated in the lower form, Fig. 73, at intervals of from six to twelve 
hours. Should the temperature at any time reach 100° F., reduce 
the current or temporarily interrupt the charge so as not to exceed 
this temperature. 



368 f^ 

, Google 



Digitized by UOOQ I 



ELECTRIC AUTOMOBILES 109 

Maintain the level of the electrolyte by adding water as neces- 
sary. Never add water just before taking hydrometer readings 
because it would not have time to mix with the electrolyte and would 
give a misleading reading. Hydrometer readings should be corrected 
for any substantial change in the temperature, as detailed in the 
section on the Use of the Hydrometer, Part I. When the gravity of 
the pilot cell has shown no further rise for a period of twenty-four 
hours, record hydrometer readings of each cell in the column marked 
"specific gravity", Fig. 73. In recording readings, start at the posi- 
tive terminal of cell No. 1, and follow the direction of the electric 
circuit. Individual cell readings should be recorded at intervals of 
about twelve hours to insure that each reaches a maximum. Bear in 
mind that the object of the initial charge is to remove all acid com- 
bined in the plates.' 

Do not stop the initial charge just because a specific gravity of 
1.270 or 1.280 may have been reached, because this may not be the 
maximum. Continue to charge as long as the gravity continues to 
rise. The charge can be considered complete only when there has 
been no rise in the gravity of any cell during a period of twenty-four 
hours of continuous charging. In case the gravity rises about 1.290 
in any cell, draw off its electrolyte down to the top of the plates and 
replace with water, saving this electrolyte for adjusting the specific 
gravity of the cells as follows: Upon completion of the charge adjust 
the specific gravity to its proper value (1.270 to 1.280), using water 
or electrolyte as may be required, and bring the level of the electrolyte 
to a uniform height of § inch above the tops of the plates. Some 
variation on the specific gravity among different cells is to be expected, 
since the amount of water in the separators and difference in level 
when filled affect this. 

Importance of Initial Charge. The foregoing outline of procedure 
is based on the assumption that the initial charge is continuous, since 
this will require the shortest time. It is especially desirable that the 
first twenty-four hours of the charge be given without interruption, 
even if the entire charge cannot be made continuous. Where there 
are interruptions, the twenty-four hours of maximum gravity must 
be actual charging time and must not include any idle time. The 
accuracy of the ammeter should be checked for the current readings 
used. 



369 

.Google 



Digitized by VjOOQI 



110 



ELECTRIC AUTOMOBILES 



A battery which has not received sufficient initial charge cannot 
be expected to give satisfactory service and life. Therefore, in case 
of any doubt, prolong the charge rather than run the chance of stop- 
ping it too soon. As a further precaution, it is advisable to see that 
the first few charges after the battery goes into service are somewhat 
prolonged. 

Test Discharge. After giving the battery its initial charge, 
it is customary to make a test discharge and, if necessary, recharge 
and make a second test discharge, to avoid the possibility of the bat- 
tery being put into service with any low cells in it caused by defective 




Fig. 74. Wiring Diagram for Battery Test Discharge, Using Rheostat 

assembly. The test is also made to determine its capacity. Capacity, 
however, does not necessarily indicate the completeness or incom- 
pleteness of the initial charge. The only sure indication is the maxi- 
mum specific gravity reached in each cell. This test discharge should 
preferably be made at the normal discharge rate of the battery and 
may be carried out with the aid of a rheostat, as shown in Fig. 74, or, 
where one of this or similar type is npt available, by constructing an 
emergency water rheostat, as shown in Fig. 75. The container should 
preferably be a wooden tub or an earthenware jar, as a metal container 
naturally would not be suitable, since the current could then follow 
a shorter path from the electrodes to the container instead of being 
compelled to pass through the solution between the electrodes. The 



370 



Digitized by 



Google 



ELECTRIC AUTOMOBILES 



111 



solution employed is weak electrolyte, while the electrodes may be 
either strips of metal or pieces of carbon. They should be mounted 
on a piece of board so that the distance between them may be 
adjusted, as the amount of current that flows will depend upon this 
distance. Separating them further will decrease the amount of 
current passing, while bringing them closer together will increase it, 
the rate of discharge being shown by the ammeter. In case the rate 
is too high at the maximum distance to which the electrodes can be 
separated, weaken the electrolyte solution of the rheostat by adding 
more water or, if necessary, make it plain water. If the rate of dis- 



ffmmeter- 




Weak Electrolyte' 

Wedge for Hold inq j/ 

Sleet rode as Jfdjustedz 



Fig. 75. Wiring Diagram for Battery Test Discharge, Using Water Rheostat 



charge is insufficient even when the electrodes are brought close 
together, strengthen the electrolyte slightly. A convenient form for 
keeping the discharge record is shown by Fig. 76. Should a second 
test discharge be made, the capacity will be less than the first, but, 
after Several discharges, the battery will not only recover but will 
exceed its first capacity. 

Recharging. The battery should then be fully charged, and the 
specific gravity of the electrolyte adjusted to the proper point. On 
this occasion, all the precautions mentioned in connection with the 
initial charge and the polarity of the charging connections must be 



371 



Digitized by 



Google 



112 ELECTRIC AUTOMOBILES 

observed. The battery should then be fully discharged. (Fig. 74 
shows the method of connecting the battery to discharge through a 
rheostat, while the water resistance described is illustrated by Fig. 75.) 



laadiajaaMp to wanted la Maak colunna. ptaaar tomdtajj bataa flltod la. 

al «Mhat(a tofara aklaaMtt. aaka a nota to Ute aflacf la tto ajiae* ptoMda* toe fa 



REMARKSi 



Fig. 76. Specimen Battery Discharge Record 
Courtesy of Electric Storage Battery Company, Philadelphia, Pennsylvania 

If a suitable resistance is not at hand for this purpose, a water resist- 
ance may easily be made as follows: 

Take a vessel of wood, or any other material except metal, and 
fill it almost full of a diluted solution of sulphuric acid and water. Con- 
nect the ammeter to one plate of metal and the battery to a second 
plate of metal, both of which should be suspended in the solution, care 



372 Digitized by G00gk 



ELECTRIC AUTOMOBILES 113 

being taken to prevent the current from passing from one plate to the 
other except through the solution. The remaining terminal of the 
battery and of the ammeter should be connected together. There is 
then a complete circuit through the improvised resistance, and the 
strength of the current may be varied by placing the plates nearer 
together or farther apart, or by adding acid to the solution, either of 
which operations will decrease the resistance* This should be adjusted 
until the ammeter shows that the battery is discharging through the 
resistance at its normal rate. After cleaning, the capacity of a battery 
may not be as great as it was previous to the operation until it has had 
several charges and discharges. While dismantled, the wood trays 
of the battery should be well rinsed with a strong solution of bicar- 
bonate of soda and water in order to neutralize any acid on them. 
After that, they should be well rinsed with water and, when dry, 
painted with acid-resisting paint. 

PUTTINQ BATTERY OUT OF COMMISSION 

Methods of Storage. When a battery is not to be used for some 
time, it must be specially prepared before being stored. There are 
two general methods of preparing a battery for storage, one known as 
"wet storage" and the other as "dry storage", the method adopted 
depending upon the condition of the battery and the length of time 
it is to be out of commission. The wet-storage method is usually 
applied to any battery that is to be out of commission for less than a 
year, provided its condition is such that it will not soon require repairs 
necessitating dismantling it. The dry-storage method is used for any 
battery that is to be out of commission for more than a year, regardless 
of its condition, and it is also applied to any battery that will shortly 
require repairs necessitating its dismantling. 

Wet Storage. Examine the condition of the plates and separators 
and also the amount of sediment in the bottom of the jars. If it is 
found that there is very little sediment and the plates and separators 
are in sufficiently good condition to give considerable additional 
service, the battery may be put into wet storage by giving it an 
equalizing charge and covering it to exclude dust. Replace evapora- 
tion periodically by adding distilled water to maintain the level of the 
electrolyte i inch above the top of the plates. At least once every 
four months, charge the battery at one-half the normal finishing 

373 



114 ELECTRIC AUTOMOBILES 

rate until all the cells have gassed continuously for at least three Jiours. 
Any cells not gassing should be examined and the trouble remedied. 

Dry Storage. When the examination shows that the battery 
will soon require repairs that necessitate dismantling, it should be put 
into dry storage. Dismantle the battery in accordance with the 
instructions given in a preceding section under this head, first making 
the sketch of the layout and connections as there illustrated. If the 
positive plates show much wear, they should be scrapped; if not, 
remove any loose particles adhering to them by passing a smooth pad- 
dle over the surface but do not wash the positive plates. Charged 
negative plates will become hot in a short time when exposed to the 
air; they should be allowed to stand in the air until cooled. 

Empty the electrolyte out of all the jars into a glazed earthenware 
jar or lead-lined tank and save it for giving the negative plates their 
final treatment before storage. Wash all the sediment out of the 
jars; wash the rubber separators carefully, dry them, and tie them in 
bundles. Place the positive groups in pairs, put them into jars, and 
store them away. Place the negative groups together in pairs, put 
into the remaining half of the jars, cover them with the electrolyte 
saved for the purpose, and allow them to stand in it for five hours at 
least. Then pour off the electrolyte, which may now be discarded, 
and store away the jars containing the negatives. If the negative 
plates showed any bulging of the active material, they should be 
subjected to the pressing treatment first, using boards and a vise 
as described in connection with dismantling the battery. The jars 
containing the positives, as well as those containing the negatives, 
should be well covered to exclude all dust. 

Make a memorandum of the amount of material required to 
reassemble the battery and, when ordering this, provide for extra 
jars and covers, extra rubber separators, and an entire lot of wood 
separators, with a sufficient excess to take care of possible breakage in 
handling. Unless the old connectors were very carefully removed, 
order a new set. Include a supply of new electrolyte of 1.300 specific 
gravity to fill all the jars. It is always well to advise the customer 
when the battery is put in storage of the material that will be neces- 
sary to reassemble it and request that at least a month's notice be 
given in which to procure it. To reassemble the battery, proceed as 
in making a complete renewal of the elements. 

374 



ELECTRIC AUTOMOBILES 115 

MISCELLANEOUS OPERATIONS 

Lead Burning. Type of Outfit In the manufacture of storage 
batteries and in garages where a large number of batteries are 
maintained, a hydrogen-gas apparatus is employed for this purpose. 
For the electric-car owner or the garage doing a comparatively small 
amount of battery repair work, the Electric Storage Battery Com- 
pany has placed an arc lead-burning outfit on the market. This 
is low in first cost and, with a little practice, good results can be 
obtained with it. As the battery itself supplies the power neces- 



Fig. 77. Arc-Welding Outfit for Burning Connections 

sary, the only material required is the lead in the form of a flexible 
strip or heavy wire. The complete outfit is illustrated in Fig. 77. 
At one end is the clamp for making electrical connection, while at 
the other is a clamp of different form having an insulated handle 
and holding a quarter-inch carbon rod. The two are electrically 
connected by a flexible cable. This simple outfit can be employed 
in two ways, the second being preferable for the beginner, at least 
until a sufficient amount of skill has been acquired to use the arc 
without danger of melting the straps. 

First Method of Burning. In the first method, a potential of 
from 28 to 30 volts (12 to 15 cells) is required. The clamp should, 
therefore, be fastened to the positive pole of the twelfth to the 
fifteenth cell away from the joint t<J be burned, counting toward the 



375 



Digitized by VjOOQ IC 



116 ELECTRIC AUTOMOBILES 

negative terminal of the battery. The carbon then forms the negative 
terminal of the circuit. Otherwise particles of carbon will be carried 
into the joint, as the carbon rod quickly disintegrates when it forms 
the positive pole. The carbon should project 3 or 4 inches from the 
holder. The surfaces of the parts to be burned should be scraped 
clean and bright and small pieces of clean lead about J to § inch 
square provided for filling the joint- The carbon is then touched to 
the strap to be burned and immediately withdrawn, forming an 
electric arc which melts the lead very rapidly. By moving the carbon 
back and forth the arc is made to travel over the joint as desired, the 
small pieces of lead being dropped in to fill the gap as required. 
Owing to the high temperature generated, the work must be carried 
out very quickly, otherwise the whole strap is liable to melt and run. 

As this method is difficult and requires practice to secure good 
results, the beginner should try his hand on some scrap pieces of 
lead before attempting to operate on a cell. Its advantages are 
that, when properly carried out, it takes but a short time to do the 
work, and the result is a neat and workmanlike joint. It is extremely 
hard on the eyes, however, and should never be attempted without 
wearing smoked or colored glasses, and even with this protection 
the eyes should be directed away from the work as much as possible. 

Second Method of Burning. The second method, utilizing the 
hot point of the carbon rod instead of the arc, is recommended for 
general practice. Scrape the parts to be joined and connect the 
clamp between the third and fourth cells from the joint. With this 
method it is not necessary to determine the polarity of the carbon. 
The latter is simply touched to the joint and held there; on account 
of the heavy flow of current it rapidly becomes red- and then white- 
hot. By moving it around and always keeping it in contact with 
the metal, the joint can be puddled. To supply lead to fill the joint, 
an ordinary lead-burning strip can be used, simply introducing the 
end into the puddle of molten lead, touching the hot carbon. The 
carbon projecting out of the holder should be only an inch, or even 
less, in length. After the joint has been made, it can be smoothed 
off by running the carbon over it a second time. 

Use of Forms to Cover Joint. In joining a strap which has been 
cut in the center, it is best to make a form around the strap by means 
of a piece of asbestos sheeting soaked in water and fastened around 

376 

Digitized by VjOOQlC 



ELECTRIC AUTOMOBILES 117 

the strap in the shape of a cup, which will prevent the lead from 
running down. It will be found that sheet asbestos paper is thick 
enough, but it should be fairly wet when applied. By this means 
a neat joint can be easily made. The asbestos will adhere very 
tightly to the metal, due to the heat, but can be removed by 
wetting it again. When burning a pillar post to a strap, a form 
may be made around the end of the strap in the same manner, 
though this is not necessary if reasonable care is used. Two or 
three pieces of 3^-inch strap iron about one inch wide and some 
iron nuts about one inch square are also of service in making the 
joint, the strap iron to be used under the joints and the nuts at 
the side or ends to confine the molten lead. Clay can also be 
used in place of asbestos, wetting it to a stiff paste. As the 
holder is liable to become so hot from constant use as to damage 
the insulation, besides making it uncomfortable to hold, a pail of 
water should be handy and the carbon dipped into it from time to 
time. This will not affect its operation in any way, as the carbon 
becomes hot again immediately the current passes through it. 

Oxy-Acetylene Blowpipe. In most garages an oxy-acetylene 
outfit is available which may be advantageously used for lead- 
burning work. The blowpipe should be handled so that the flame 
wilt strike the work perpendicularly; this will prevent the flame 
from heating the surrounding metal too high. To make a success- 
ful job the operator must do the work quickly, bringing the flame 
down to the work, fusing the metal, adding the necessary burning 
bar or filling wire, smoothing off the work, and removing the flame 
— all as rapidly as possible. When burning plates to terminal 
bars, a small flame should be used and the work should be held in 
a fixture. The small ends on the plates should extend up into the 
terminal bar slots about two-thirds of the way. The burning 
should be carried on by. first fusing the end of the plates to the 
bottom of the slots, then filling up the rest of the slot by adding 
lead from a coil of wire or a burning bar. 

When working on links and poles it is advisable to do only 
part of one pole, move to another for a few minutes, and then 
come back to the first for 4, few minutes. This will allow the 
work to cool off slightly and will prevent breaking down or melt- 
ing away. When burning this class of work, especially if the lead 

Digitized by VjOOQ IC 



118. ELECTRIC AUTOMOBILES 

is old and pitted with dirt and cut by acid, it is advisable to 
use an oxidizing flame when working down in the pocket. 

Freezing. In addition to taking care that the temperature of 
the cells does not exceed 100° F. on charge, precautions are also 
necessary to prevent the temperature of the battery falling too 
low, as a drop in temperature causes a falling off in the efficiency. 
This is particularly true of the alkaline battery, the output curve 
of which drops off rapidly below 60° F., so that this type of bat- 
tery is usually installed in a manner which keeps it at an even 
temperature, making it possible to operate it successfully in zero 
weather. Furthermore, in the case of the lead cell, freezing must 
be guarded against. To avoid this, the battery should always be 
kept fully charged in cold weather, as a charged cell will not freeze 
in the temperatures ordinarily experienced. Electrolyte will freeze 
at various temperatures, according to the state of charge as follows: 

Sp. Gr. 1.120 battery fully discharged 20° F. above zero 

Sp. Gr. 1.160 battery three-quarters discharged Zero F. 

Sp. Gr. 1.210 battery half-discharged 20° F. below zero 

Sp. Gr. 1.260 battery one-quarter discharged 60° F. below zero 

When a battery is stored away for the winter, care should be 
taken not to let the temperature of the place in which it is kept 
fall below 20° F., or else the battery should be kept fully charged. 

Putting New Battery in Commission. One of the things tnat 
the garage man caring for electric vehicles will be called upon to 
do at intervals will be the ordering and installation of a new bat- 
tery in a car. As received from the manufacturer, the battery is 
in a charged condition, but it must be inspected and tested before 
being placed in the car. 

Inspection of Battery. To avoid spilling the electrolyte from the 
cells, care must be taken in unpacking the trays. After cleaning off 
the excelsior and other packing from the tops of the cells, the soft 
rubber plugs should be removed from all the latter to note if they 
all contain the proper amount of electrolyte. This should be \ inch 
over the tops of the plates. If the electrolyte is uniformly below the 
proper level in all the cells, this is evidently due to evaporation; add 
enough distilled or rain water to bring the level to the proper height. 
But if the level of the electrolyte is found to be low in some cells only 
this is due to loss of electrolyte. If this has resulted from the tra\ 

Digitized by VjOOQIC 



ELECTRIC AUTOMOBILES 119 

having been turned over in shipment, the excelsior around the top of 
the tray will be wet (the acid does not evaporate), and some acid 
would be spilled from all the cells in that tray. In this case, replace 
the amount lost by filling the low cells to the proper height with chemi- 
cally pure electrolyte of 1.250 specific gravity (seven parts of water 
to two pure sulphuric acid, by volume). 

Replacements. If the electrolyte in a cell is low, due to a broken 
jar, the bottom of the tray will be wet, though the excelsior around the 
the top may be dry. Replace the broken jar as detailed in the instruc- 
tions given under that heading and add sufficient electrolyte of 1.250 
specific gravity to make up for that lost. Should it be found, after 
replacing the broken jar and giving the battery an equalizing charge, 
that the gravity does not reach approximately 1.275, it is due to 
not having replaced the same amount of acid as was spilled. To 
adjust this, draw off with a syringe some of the electrolyte from the 
top of the cell and add water or 1.300 acid to bring the specific gravity 
to between 1.270 and 1.280. 

Charging. Put the battery on charge at the low rate given on the 
name plate on each tray. Charge at about this rate until all the 
cells gas uniformly. Reduce the current to one-half that rate and 
continue the charge for three hours longer, when the battery will be 
ready to plut into service. It is advisable, however, before putting 
the battery into service, to take and record the specific gravity of the 
electrolyte of each cell and the temperature of one or more of the cells. 

Packing a Battery. It is sometimes necessary to ship a battery 
back to the manufacturer for repairs, and the amount of damage 
occasioned in transit by improper packing has led the makers to issue 
special instructions for doing this. A box at least 2 inches larger in 
each direction than the overall size of the battery tray should be made 
of strong 1-inch or lj-inch planks. It should be made with an A- 
shaped top to prevent placing it any other way than upright. Where 
more than one tray is shipped in a box, 2 inches must be allowed 
between the trays. The maximum permissible weight, however, is 
200 pounds. Cover the bottom of the box with a layer of sawdust, 
excelsior, or coarse shavings to a depth of 2 inches, and on this place 
the tray of cells. Over the top of the cells place paraffined paper and 
then cover the whole tray with stout wrapping paper, folding it down 
over the sides of the tray to keep packing material and dust out of 

Digitized by VjOOQ IC 



120 ELECTRIC AUTOMOBILES 

the cells. Fill the space around the sides with sawdust or excelsior, 
or even with waste paper twisted into balls and wads, ramming the 
whole down tightly so that the tray cannot move. Nail slats on the 
box for a cover (never make a solid cover), and nail a stout strip on 
each side extending beyond the ends, for handles. The slatted cover 
enables the freight handlers to see the contents and makes for more 
careful handling. Label the box "handle with care" and "do not 
drop". Put your own name and address on the package as well as 
that of the battery manufacturer, and notify the latter of the ship- 
ment. Complete batteries should be shipped as "electric storage 
batteries assembled". No railroad caution labels are required as the 
electrolyte in the cells is so dilute that acid in this form is exempted 
from the rules applying to its shipment in other forms. Boxes of good 
elements, or plates, should be shipped as "Lead Battery Plates", 
while worn-out plates may be shipped as "Scrap Lead", boxes of jars 
as "Rubber Battery Jars", covers and separators as "Rubber Goods", 
and empty trays as "Empty Wood Crates". By properly designating 
the material as above in the bill of lading, the most favorable freight 
rate may be obtained. 

Causes of Low Battery Power. A decrease in the speed or mileage 
of a car does not necessarily mean a lack of Capacity in the battery. 
If the current consumption is greater than normal, it may be due to 
trouble with the transmission, motor, or running gear— the car 
"runs hard" — or it may be due to poor connections. When other 
causes fail, then it is probably the battery, and its lack of capacity 
may always be traced to some definite cause. There may be a dry 
cell, due to a leaky jar; some or all of the cells may be in a state of 
incomplete charge, due to the battery having been run too low and 
not sufficiently charged. The plates may be short-circuited by 
excessive deposit of sediment, or by something falling into the jar. 

If the trouble cannot be located upon examination, connect the 
battery in series and discharge it at the normal rate through a suitable 
resistance, as already explained. As the discharge progresses the 
voltage will gradually decrease, and it should be frequently read at 
the battery terminals. As soon as it shows a sudden drop, the voltage 
of each cell should be taken with a low-reading voltmeter. While 
the readings are being taken, the discharge rate should be maintained 
constant, and the discharge continued until the majority of the cells 



380 



Digitized by VjOOQ IC ' 



ELECTRIC AUTOMOBILES 121 

read 1.70 volts. Those reading less than this should be noted. The 
discharge should then be followed by a charge until the cells which 
show 1.70 volts are up. Then the low cells should be cut out and 
examined and the trouble remedied. Assuming that there are no 
short-circuits, low specific gravity of the electrolyte in such a cell 
will indicate stoppage or a leak, the loss from which has been replen- 
ished with water alone. Or it will be a sign of insufficient charge, 
over-discharge, standing in a discharged condition, or a combination 
of these abuses. Any one of these indicates that there is acid in 
combination with the active material of the plates, and it should be 
brought out by a long charge at one-quarter the normal discharge 
rate. Continue charging until the specific gravity of the electrolyte 
stops rising;, then adjust to normal (1.270 to 1.280) by drawing off 
some of the electrolyte and adding water if it be above normal, and 
by adding acid if it be below normal. The low cells should be 
grouped by themselves and charged as a separate battery. 

STANDARD INSTRUCTIONS FOR STORAGE BATTERIES 
As Issued by the Society of Automobile Engineers 

1. Batteries must be properly installed. 

Keep battery securely fastened in place. 

Battery must be accessible to facilitate regular adding of water to, and 
occasional testing of, solution. Battery compartment must be ventilated and 
drained, must keep out water, oil, and dirt and must not afford opportunity for 
anything to be laid on top of battery. Battery should have free air space on all 
sides, should rest on cleats rather than on a solid bottom and holding devices 
should grip case or case handles. A cover, cleat, or bar pressing down on the 
cells or terminals must not be used. 

2. Keep battery and interior of battery compartment wiped clean 
and dry. 

Do not permit an open flame near the battery. 

Keep all small articles, especially of metal, out of, and away from, the bat- 
tery. Keep terminals and connections coated with vaseline or grease. If 
solution has slopped or spilled, wipe off with waste wet with ammonia water. 

3. Pure water must be added to all cells regularly and at suffi- 
ciently frequent intervals to keep the solution at the proper height. 

The proper height for the solution is usually given on the instruction' or name- 
plate on the battery. In all cases the solution must cover the battery plates. 

The frequency with which water must be added depends largely upon the 
battery, the system with which it is used, and the condition of operation. Once 
every two weeks is recommended as good practice in cool weather; once every 
week in hot weather. 

Plugs must be removed to add water; then replaced and screwed home after 
filling. 



Digitized by VjOOQ IC 



122 ELECTRIC AUTOMOBILES 

Do not use acid or electrolyte, only pure water. 

Do not use any water known to contain even small quantities of salts of any 
kind. Distilled water, melted artificial ice, or fresh rain water are recommended. 
f Use only a clean non-metallic vessel. 

Add water regularly, although the battery may seem to work all right 
without it. 

4. The best way to ascertain the condition of the battery is to 
test the specific gravity (density) of the solution in each cell with a 
hydrometer. 

This should be done regularly. 

A convenient time is when adding water, but the reading should be taken before, 
rather than after, adding the water. 

A reliable specific gravity test cannot be made after adding water and before it 
has been mixed by charging the battery or by running the car. 

To take a reading, insert the end of the rubber tube in the cell. Squeeze 
and then slowly release the rubber bulb, drawing up electrolyte from the cell 
until the hydrometer floats. The reading on the graduated stem of the hydrome- 
ter at the point where it emerges from the solution is the specific gravity of 
the electrolyte. After testing, the electrolyte must always be returned to the cell 
from which it was drawn. 

The gravity reading is expressed in "points", thus the difference between 
1250 and 1275 is 25 points. 

5. When all cells are in good order the gravity will test about the 
same (within 25 points) in all. 

Gravity above 1200 indicates battery more than half charged. 

Gravity below 1200 but above 1150 indicates battery less than half charged. 

When battery is found to be half discharged, use lamps sparingly until, by 
charging the battery, the gravity is restored to at least 1200. See Section 8. 

Gravity below 1150 indicates battery completely discharged or "run down". 

A run-down battery should be given a full charge at once. See Sections 
7 and 8. 

A run-down battery is always the result of lack of charge or waste of cur- 
rent. If, after having been fully charged, the battery soon runs down again, 
there is trouble somewhere else in the system, which should be located and 
corrected. 

Putting acid or electrolyte into the cells to bring up specific gravity can do 
no good and may do great harm. Acid or electrolyte should never be put into 
the battery except by an experienced battery man. 

6. Gravity in one cell markedly lower than in the others, especially 
if successive readings show the difference to be increasing, indicates that 
the cell is not in good order. 

7/ the cell also regularly requires more water than the others, a leaky jar is 
indicated. 

Even a slow leak will rob a cell of all its electrolyte in time, and a leaky jar 
should be immediately replaced with a good one. 

// there is no leak and if the gravity is, or becomes, 50 to 75 points below that 
in the other cells, a partial short-circuit or other trouble within the cell is indicated. 

A partial short-circuit may, If neglected, seriously injure the battery and 
should receive the prompt attention of a good battery repair man. 



382 .Google 



Digitized by VjOOQI 



ELECTRIC AUTOMOBILES 123 

7. A battery charge is complete when, with charging current flow- 
ing at the rate given on the instruction-plate on the battery, all cells 
are gassing (bubbling) freely and evenly and the gravity of all cells has 
shown no further rise during one hour. 

The gravity of the solution in cells fuUy charged as above is 1,275 to 1,800. 

8. The best results in both starting and in lighting service will be 
obtained when the system is so designed and adjusted that the battery 
is normally kept well charged, but without excessive overcharging. 

//, for any reason, an extra charge to maximum specific gravity is needed, it 
may be accomplished by running the engine idle, or by using direct current from an 
outside source. 

In charging from an outside source use direct current only. Limit the 
current to the proper rate in amperes by connecting a suitable resistance in series 
with the battery. Incandescent lamps are convenient for this, purpose. 

Connect the positive battery terminal (painted red, or marked POS or 
P or +) to the positive charging wire and negative to negative. If reversed, 
serious injury may result. Test charging wires for positive and negative with a 
voltmeter or by dipping the ends in a glass of water containing a few drops of 
electrolyte, when bubbles will form on the negative wire. 

9. A battery which is to stand idle should first be fully charged. 
See Sections 7 and 8. 

A battery not in active service may be kept in condition for use by giving it a 
freshening charge at least once every two months, but should preferably also be given 
a thorough charge, after an idle period, before it is replaced in service. 

A battery which has stood idle for more than two months should be charged at 
one-half normal rate to maximum gravity before being replaced in service. 

It is not wise to permit a battery to stand for more than six months without 
charging. 

Disconnect the leads from a battery that is not in service so that it may not 
lose through any slight leak in car wiring. , t 

SOME SOURCES OF POWER LOSS 

As the power of the electric vehicle is closely limited by the 
capacity of the battery it carries, it is absolutely essential that every 
part of the mechanism be kept in good running order so that none 
of the power may be wasted. Whether the machine is considered 
as a whole, or each component is treated separately, the electric 
vehicle is about as simple as it possibly could be. But the number 
of places at which power losses may occur will greatly surprise the 
uninitiated owner when he comes to look into the subject. It is 
nothing unusual for the purchaser of an electric vehicle to write the 
maker a year or so after he has bought it that while the car ran per- 
fectly satisfactorily at first, its mileage has now been very much 
reduced. He has followed instructions implicitly, the battery has been 
well looked after, and, according to all indications, it is in as good 



383 Digitized by G00gle 



124 ELECTRIC AUTOMOBILES 

condition as ever it was, but it is impossible to obtain anything like 
the rated mileage from a full charge of the battery. A little investi- 
gation will show that, in the majority of cases, the owner, who has 
not had the advantage of a mechanical training, has become so 
impressed with the great importance of properly maintaining the 
electrical end of the car that he has disregarded its mechanical 
efficiency entirely. 

Non-Alignment of Steering Wheels. One of the most prolific 
sources of power losses, and one of the last to be suspected, is non- 
alignment of the wheels. A chance blow in drawing up along- 
side a curb is sometimes sufficient to make one of the front wheels 
"toe in" slightly. The fault is not noticed and may be aggravated 
by subsequent blows at the same spot, or on the other wheel. This 
may cause the bearings to bind to a certain degree and also to impose 
a heavy load on the motor by the new angle which the tires make 
with, the road surface. It is difficult for the average layman to 
appreciate how great an increase in the load such a seemingly trivial 
fault as this may create, and it can only be realized to a certainty by 
keeping a record of the ammeter readings at all of the speeds under 
normal conditions. Just how much current is required to start and 
to mount various grades should be noted. As the service of an 
electric vehicle is chiefly confined to urban travel and covers prac- 
tically the same routes day after day, it is possible to keep a close 
check on current consumption by noting how far the ammeter 
needle travels over the dial in running on the level and in mounting 
grades that have to be climbed frequently. Small increases in the 
current required to do the same work at different times would then 
be readily apparent, and as the malady is imposing an extra drain 
on the battery, which is simply a waste of energy, its cause should 
be looked for and remedied. 

The electric vehicle is a power-measuring machine without an 
equal, and the driver who has familiarized himself with the per- 
formance of his car under favorable conditions should be able readily 
to detect the presence of trouble by the increased current consump- 
tion and the correspondingly decreased mileage per charge. The 
causes may be electrical as well as mechanical, and where a car has 
not been properly looked after, it is more than likely that the falling 
off in the available radius on a single charge will be traceable to an 

384 'Digitized by G00gle 



ELECTRIC AUTOMOBILES 125 

accumulation of causes small in themselves, but of considerable 
importance in the aggregate. Disalignment of the front wheels 
may sometimes be due to the steering gear — that is, the connecting 
rod which serves to keep these wheels parallel — working out of 
adjustment. Unless they are perfectly aligned, they not only make 
more current necessary to propel the vehicle, but they also serve to 
wear out the front tires more rapidly than would otherwise be the 
case. Sagging of the rear axle, which was not an uncommon fault 
in earlier years, but which is now rare, will produce similar conditions 
at the rear wheels and, as the entire power of the car is utilized at 
this point, the result is just that much worse. 

Worn Chains and Sprockets. Next in the order of importance 
to badly aligned driving or steering wheels from a mechanical point 
of view, comes a worn driving chain. This naturally applies to the 
chains employed for either of the reductions in motor speed. It is 
likewise equally true of the sprockets, but a worn sprocket is prac- 
tically always the Tesult of the continued use of an old chain. The 
la tter is allowed to wear to a point where its pitch is greater than that 
of the teeth of the sprocket, and, in consequence, the chain shows a 
constant tendency to ride the teeth of the sprocket instead of fitting 
snugly between them, as should be the case. This tightens the chain 
and imposes a greatly added load upon it and the sprocket, with the 
result that the teeth of the latter are also soon worn out of pitch. 
When this occurs, the only remedy lies in the replacement of both 
chains and sprockets, as the fitting of a new chain on a worn sprocket 
aggravates the evil and causes the new chain to wear to a point of 
uselessness in a very short time. The best preventive is to watch 
the driving chains for such conditions and to replace a chain as soon 
as it gives any indication of mounting the teeth instead of running 
smoothly. 

These instructions apply only to pleasure models antedating 
1913-14, as practically all models are now made with the shaft drive 
using a bevel gear or worm; but there are thousands of the older 
chain-driven cars in service, the electric having a much longer 
effective life than the gasoline car. 

Non-Alignment of Axles. On all electric cars, whether they be 
of the chain- or shaft-driven variety, it will be found that some 
means are provided for aligning the rear axle. These take the form 

385 Digitized by G00gle 



126 ELECTRIC AUTOMOBILES 

of distance or radius rods, attached through the medium of a hinge 
joint to the axle and some form of pivot joint at the countershaft, this 
construction having been referred to in connection with the descrip- 
tion of the transmission of a double chain-driven car. Although 
effective means of locking these rods are provided, they are sub- 
jected to constant vibration and jolting and sooner or later will 
require attention. It will be apparent that if one is adjusted so as 
to be somewhat shorter than the other, an excessive fraction of the 
load will be imposed on the driving chain on the short side. This 
will also place a very heavy strain on the differential or balance gear, 
and a greatly added amount of power will be required to drive the 
car. The importance of accurately adjusting the distance rods so 
that the rear axle will be at right angles with the frame anr of main- 
taining it in that condition may accordingly be appreciated. 

Dry Bearings. It would appear almost superfluous to mention 
lack of oil as a mechanical source of power loss, but many electric 
vehicle owners seldom attach sufficient importance to the necessity 
for oiling the moving parts. It is a popular fallacy, quite generally 
indulged in, that the anti-friction bearing is a mechanical device that 
requires no lubrication. Ball bearings do call for less attention 
in this direction than any other. They need very little oil, and at 
much longer intervals than a plain bearing, but they cannot render 
efficient service without some lubricant. In fact, it is this very abil- 
ity to stand an uncommon amount of abuse that seems to have earned 
for the ball bearing its popular reputation for ability to run quite as 
well whether it is dry or oiled. The lubricant not only serves the 
same end that it does in any bearing — that of reducing friction, but 
it also acts as a preventive of rust — the greatest enemy of the ball 
bearing; and as these bearings are rather expensive replacements, it 
pays to avoid this by regular oiling at least once a month. Only the 
best grade of light machine oil should be employed, or a thin-bodied 
and highly-refined vaseline with which the bearing may be packed. 
It is quite essential that the lubricant should be entirely free from 
acid, which would attack the highly polished surfaces of the balls 
and races and destroy the efficiency of the bearing. The electric- 
vehicle user's chief safeguard against this is to confine his purchases 
to brands recommended by the manufacturer of the car. Where 
the presence of acid is suspected, a simple test may be made by 



.Google 



Digitized by VjOOQI 



ELECTRIC AUTOMOBILES 12,7 

dipping a small piece of cotton waste in the lubricant and then 
wrapping it around a piece of polished steel. This should be placed 
in the sun and examined at the end of a Keek or more. If the lub- 
ricant contains acid, there will be traces of its etching effect on the 
polished surfaces and it is useless. Oil that is entirely free from acid 
will not affect the most highly polished surface. 

Wheels and axles out of alignment, worn chains and sprockets, 
improperly adjusted brakes, which may be dragging, and neglected 
bearings sum up the chief mechanical sources of power loss. 

It is quite as important, however, that losses of electric power 
be guarded against, as they interfere with the efficient utilization of 
the energy stored in the batteries and decrease the available mileage 
on a charge, regardless of the condition of the mechanism. Vibra- 
tion will prove the undoing of almost anything in the course of time, 
and, while every precaution is taken by the manufacturer to provide 
durable and permanent connections, it seems practically impos- 
sible to provide a form of terminal that will be absolutely proof 
against this influence and still permit of being disconnected con- 
veniently when required. Air interposes a very high resistance 
in a circuit, and but a slight amount of looseness in a connection 
creates an air gap that must be bridged by the current in order to 
complete the circuit. This causes arcing, or a flashing of the current 
across the gap, which is destructive of the terminals and is not in- 
frequently responsible for the ignition of adjacent material. As will 
be apparent from the wiring diagram given, there are quite a number 
of such connections, and going over them systematically at regular in- 
tervals is the only way to guard against current losses from this source. 

Brushes and Commutator. The brushes and commutator are 
the only parts of the electric motor that are subject to wear, and 
the life of the commutator is naturally equivalent to that of several 
sets of brushes, so that the latter constitute practically the sole item 
to be looked after in connection with the motor. They are either 
plain blocks of carbon, or carbon with fine copper wire embedded 
in it, and are held against the commutator by springs. To examine 
their condition closely, the housing should be removed, the rear axle 
jacked up, and the motor run on the first speed. No attempt should 
be made to run it on any of the other speeds when in this condition, 
nor should it be run any longer than necessary. This does not 



387 Digitized by G00gle 



128 ELECTRIC AUTOMOBILES 

exactly simulate actual driving conditions as, with the wheels off 
the ground, practically no load is imposed on the motor and, while 
the latter may spark badly under load, it will frequently give little 
indication of this form of trouble when running light. 

If the brushes have been sparking badly in actual service there 
will be certain signs of this in the shape of the blackened commutator 
bars. They should be wiped clean and, if any oil has leaked on to 
them from the bearing, all traces of it should be removed. If this 
does not suffice to remove the blackened appearance, the sparking 
has been such as to burn the copper, and this blackened surface 
should be removed with the aid of a piece of very fine sandpaper 
held against the commutator while it is turning slowly. Never use 
emery cloth for this purpose, as the abrasive material employed in 
its manufacture is of a metallic nature, and not only tends to embed 
itself in the insulation between the bars, but, once there, serves as a 
conductor and may short-circuit some of the armature coils, result- 
ing in serious damage to the motor. If the brushes merely appear 
to be glazed but still make good contact all over the bearing surface, 
the latter may be rubbed with the sandpaper as well. If they have 
worn to a point where the contact is not good, new brushes should 
be substituted, and it would be well for the owner of the electric 
vehicle who is not familiar with the motor, to ljave an experienced 
person put them in for him the first time — every time, in fact, unless 
he is perfectly sure of his own ability in this line. A set of brushes 
will seldom, if ever, need replacement more than once during an 
entire season. 

For instructions covering seating of brushes, testing springs, 
and the like, refer to sections on these faults in the article on 
Starting Motors and Lighting Generators. 

Armature Troubles. When the housing is off, the brush con- 
nections and other motor connections should be inspected for loose- 
ness or other faults. Instructions for locating grounds, short- 
circuits, or open circuits in the armature and field windings are 
given in connection with the articles on Starting and Lighting 
Systems. 

The armature is supported on annular ball bearings in the major- 
ity of cases, and while these bearings require little attention, they 
should be packed with vaseline as already directed, when needing 



388 



Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 129 

lubrication. Oil should not be used as it will flow out on to the 
commutator at one end or the armature windings at the other. 

Miscellaneous. In speaking of connections, those at the battery 
are included and they should be inspected as well. The connections 
between the different cells are usually made by burning the lead- 
strap terminals together, though some have bolted connections, and 
these may jar loose; but the various groups are connected to one 
another and to the remaining apparatus, and these terminals are 
probably more apt to give trouble than some of the others, as it is 
nothing unusual to remove the battery at times and sufficient care 
is not always exercised to have the connections solidly fast. 

The loss of electrical energy, due to undercharged and short- 
circuited cells in the battery, has been treated in detail in connection 
with the care of the battery. 

Tires are, without doubt, one of the greatest sources of power 
loss on the electric vehicle, and it is one that mystifies the uninitiated 
exceedingly. This matter is gone into at length in connection with 
tire equipment. 

TIRES AND MILEAGE 

Relation of Tires to Mileage. It will appear odd and some- 
what inexplicable at first sight that these two headings should be 
included in the same chapter, for the average man thinks that the 
only thing which has any direct in,fluence on the mileage of the car 
is the amount of energy the battery is capable of giving forth. As 
is pointed out under "Sources of Power Loss", there are many other 
factors that affect the available radius of the car more or less indi- 
rectly. Tires are not included among these indirect sources, as the tire 
equipment has a most direct and, therefore, a most important bearing 
on the distance the electric car is capable of traveling on a single 
charge of the battery. The gasoline machine is endowed with such 
a liberal surplus of driving power that the loss occasioned by tires 
represents but an insignificant fraction of the whole; in other words, 
is a totally negligible factor. Had it not been for extensive experi- 
ments carried out in connection with the electric automobile, the 
importance of these losses would not have been definitely known. 

When all the points which contribute to both the electrical and 
mechanical efficiency of the car have been carefully maintained in 



389 Digitized by G00gle 



130 ELECTRIC AUTOMOBILES 

proper working order, and still both the speed and total capacity 
of the battery fail to respond, the cause of the trouble may be 
summed up in a single word — "tires." For tires constitute the 
most important element in the determination of mileage and, 
though that fact is seldom, if ever, mentioned in connection with 
accounts of phenomenal mileages made on a single charge, they 
are the chief controlling factor. The tires usually employed for 
such "stunts" are specially made for the purpose and are not 
adapted to ordinary service. They have extremely thin walls, 
with the thread of the fabric reinforcement running continuously 
round the tread of the tire in the same direction, and are not only 
very likely to puncture on slight provocation, but are far from 
durable. The expense of employing such tires regularly would be 
prohibitive, particularly as they are very difficult to repair when 
punctured. 

Kinds of Tires. Pneumatic. On the gasoline car, in view of 
the great weights and high speeds, it is solely a question of being 
able to make the pneumatic tire sufficiently strong to stand the 
unusually severe stresses to which it is subjected. To accomplish 
this end, the fabric structure forming the foundation of the shoe, 
or outer envelope of the tire, is made of various layers of heavy 
canvas placed at angles to one another and solidly vulcanized 
together. This construction makes an extremely stiff wall, as is 
evidenced by the difficulty in forcing a clincher type of tire on to 
the rim. Such a tire will yield to the minimum degree under the 
weight of the car or road obstacles when inflated to the proper 
pressure. In consequence, it absorbs considerable power. This 
loss is still further increased by the use of chains, studs, or similar 
anti-skid devices. Tests made on the recording dynamometer of 
the Automobile Club of America in New York City have shown 
that some forms of non-skid treads, particularly those employing 
heavy steel studs embedded in thick leather, absorbed as much as 
5 horsepower per wheel to drive them, Tests showing 2 to 2\ 
horsepower per wheel were not uncommon, and in but few instances 
did the loss drop below 1 horsepower per driving wheel, regardless 
of the type of tire employed. 

It would be manifestly out of the question to expect much in 
the way of mileage from an electric vehicle if handicapped in this 

Digitized by VjOOQ IC 



ELECTRIC AUTOMOBILES 131 

manner. Non-skid devices of any kind are rarely seen on electric 
automobiles for this reason, about the only occasion when they are 
in evidence being in winter, when they are actually required on ice 
or slushy pavements to afford sufficient traction. For electric 
service a structure is required in which the fabric foundation is so 
constituted as to be able to adapt itself most readily to the distor- 
tion caused by being pressed out flat on its contact area with the 
road. 

Solid. Viewed from one aspect, the electric has an advantage 
over the gasoline car. Owing to its greatly reduced speed, the 
owner of an electric finds the solid-rubber tire a practical option. 
Naturally, there can be no comparison between the riding qualities 
of a solid and a pneumatic tire, but as most electric-vehicle work 
is over smoothly paved streets, and the reasonable driver should 
never take obstructions except at a greatly reduced speed, the 
solid tire provides an amount of comfort out of proportion to its 
greatly reduced cost as compared with the pneumatic. The mile- 
age radius possible with a good solid tire is about the same as that 
possible with the standard fabric type of pneumatic usually 
referred to by the electric-vehicle manufacturer as a "gasoline" 
type of tire, with the advantage in favor of the former in that it 
is free from puncture. 

Test Curves. An extensive investigation has been made of 
the subject of tires in the past few years and considerable data 
compiled. Herewith is given a series of curves prepared by the 
builders of the Rauch and Lang electrics which will suffice to 
reveal the great differences in tires where the question of mileage 
is concerned, Fig. 78. The curves show that of the solid types 
experimented with the Motz tire rendered the best performance. 
On referring to the chart, it will be apparent that the showing of 
the tire in question is somewhat more uniform than the Diamond 
pneumatic type. At the high limit of the range is to be found 
the Palmer cord tire, which is a single-tube type of pneumatic 
with thread fabric. Bearing in mind the fact that increasing 
speed means a corresponding reduction in the mileage, the applica- 
tion of the chart is simple. Taking the Palmer tire just referred 
to as an example, select in the vertical column at the left marked 
"miles per hour," the rate at which the car is to travel. Trace 

391 Digitized by GoO< 



132 ELECTRIC AUTOMOBILES 

this along the horizontal line representing the speed, to the right 
until it intersects the characteristic curve of the tire in question. 
At that point, rise perpendicularly to the point where the vertical 
line meets the top of the chart, which is divided into sections giv- 
ing total mileage, by increments of 10 miles. For instance, sup- 
pose it be desired to run a car at 15 miles an hour on Palmer cord 
tires. Tracing the 15-mile line to the right, it will be found to 
intersect the Palmer-tire curve at the vertical line corresponding to 
100 miles. A striking example of the manner in which mileage 
increases with reduced speed may be seen by tracing the 12§-mile 



Fig. 78. Curves Showing Tests of Various Tires Made by Rauch and Lang Carriage Company 

line to the right until it intersects the Palmer curve. It gives a 
total mileage of 123, or an increase of 23 per cent in the distance 
covered for a decrease of but 2\ miles per hour in the speed. By 
making a further reduction to 10 miles an hour, 130 miles could 
be covered on a charge. This, of course, is not due to any charac- 
teristic of the tire, but to the fact that the lower the. discharge 
rate the greater the capacity of the battery, the phenomenal mile- 
ages given being the result of employing a tire that presents the 
minimum of resistance to bending. 

New Tire Equipment. A little study of the foregoing will 
serve to reveal one of the most prolific causes of complaint on the 

392 Digitized by GoOgk 



ELECTRIC AUTOMOBILES 13» 

part of uninitiated owners of electric vehicles. After wearing out 
one or two tires in service, they instruct the garagemen to put 
"new ones" in their place, or they renew the old ones by purchas- 
ing in the open market themselves. Unless informed as to the 
purpose for which the tires are needed, both the garagemen and 
the tire salesman are more than apt to supply a gasoline type of 
tire. A distinct falling off in the mileage radius of the car is at 
once noticeable, particularly if the owner has been in the habit of 
making use of the higher speeds. The cause is apparently inex- 
plicable, and the result is a complaint to the manufacturer that 
something has gone wrong or that the car is not fulfilling the 
promises made for it, when, as a matter of fact, greater care 
should have been taken to maintain the tire equipment the same 
throughout. 

Improper Inflation. Tires have been previously mentioned as 
one of the sources of power loss, and the foregoing serves to 
explain to a great degree why this is so. An item of considerable 
importance in the treatment of tires, whjch has not been referred 
to, is improper inflation. A soft tire naturally consumes more 
power to drive it because of the increased friction due to the 
greater area of the tire in contact with the ground. Such a condi- 
tion is detrimental to the tire itself as it increases the amount of 
wear and the danger of rim cuts. 

If the tire be too soft, the weight of the car will cause it to 
spread unduly at the point of contact with the road and this con- 
dition will be immediately noticeable. On the other hand, when 
the tire is pumped up too hard, the tire will stand just as if it 
were bearing no load. Such a condition obviously places too 
great a strain on both the fabric and the rubber, and is frequently 
the cause of tire failures that are usually assigned to a totally 
different reason. With its ordinary load of passengers, the electric 
should only cause a slight flattening of the tires at the tread, 
experiment showing that the best results are obtained when the 
increase in the width of the tire is about 20 to 25 per cent, that is, 
a 3-inch tire when properly inflated should measure approximately 
3f inches across its horizontal diameter at the part in contact 
with the road. Of course, the surest method of avoiding improper 
inflation is a tire pressure gage. 

393 oogle 



134 KLI'XTRIC AUTOMOBILES 

ELECTRIC INDICATING INSTRUMENTS AND THEIR USES 

Volt-Ammeter. With an electric, it is important to watch the 
volt-ammeter. An example of this type of combined instrument is 
shown by the accompanying illustration, Fig. 79. It will be noted 
that the indicating needle of the ammeter does not go to the end 
of its scale, but reads both ways, the scale to the left hand being 
for the charging current, and that to the right for the discharging 
current. These instruments are manufactured in various forms, 
one type very much in use having the voltmeter and ammeter 



Fig. 79. General Electric Volt-Ammeter 

scales parallel in a vertical plane. Some also have the voltmeter 
scale so divided that the reading of the individual cells may be 
taken. 

By becoming familiar with the readings of the instrument and 
by realizing their significance, the driver of an electric automobile 
is in a position not only to judge whether the battery is giving the 
proper service, but he also has an accurate gage on the condition 
of the running gear and transmission of the vehicle itself. The 
instrument is capable, therefore, of giving ample warning by its 
deflections of any weakness, electrical or mechanical. 

Ampere-Hour Meter. While the volt-ammeter affords a con- 
stant indication of the working of the battery, as well as the effi- 

Digitized by VjOOQIC 



ELECTRIC AUTOMOBILES 



135 



ciency of the transmission, and is accordingly indispensable, it does 
not permit of the direct reading of the state of charge nor indicate 
off-hand how much of the energy has been utilized and how much 
remains available at any given time. For this purpose the Sang- 
amo ampere-hour meter has been developed and generally adopted 
by the builders of both pleasure and commercial electric cars. 

Method of Use. To keep the battery plates in good working 
condition, it is necessary to give the battery a certain amount of 
charge, so that under normal conditions more ampere hours must 
be put into the battery than 
can be taken out of it. This 
difference is the overcharge, 
and it must be taken into 
account in figuring the num- 
ber of ampere hours in a 
battery available for useful 
work. Since the only infor- 
mation desired by the driver 
is how much energy can be 
taken from the battery, the 
Sangamo ampere-hour meter 
is designed to compensate for 
the overcharge, and indicates 
at all times the current avail- 
able without the necessity of 
resetting the pointer every 
time the battery is charged. 
This is accomplished by means of a differential shunt, as shown by 
the diagram, Fig. 80. Two shunts are employed, and the relative 
value of their resistance is adjustable by means of the sliding con- 
nection G, so that the meter can be made to run slow on charge 
or fast on discharge, as desired. The usual method is to allow the 
meter to register less than the true amount on charge and the 
exact amount on discharge, the difference representing the loss in 
the battery, or overcharge. 

Readjusting the Meter. However, over long periods of use 
under varying conditions, the battery losses will vary and in time 
the meter and battery will get out of step. Therefore, it is good 




Fig. 



80. Circuit Diagram of Differential Shunt 
Type Sangamo Ampere-Hour Meter 



395 



Digitized by 



Google 



136 ELECTRIC AUTOMOBILES 

practice to give the battery an extra overcharge at stated intervals 
and reset the meter, a simple device being provided for this pur- 
pose. Moreover, in vehicle work the batteries are frequently 
subjected to excessively high discharge rates and, under such condi- 
tions, the battery suffers an actual loss of capacity, which requires 
further compensation, as otherwise the meter will give a false indi- 
cation of the number of ampere hours available. The variation in 
the capacity of the battery with its discharge rate is shown by the 
curves, Fig. 81. 

In the Edison battery, the transfer of active material does not 
take place between the electrolyte and the plates, but from one 



Fig. 81. Variation of Useful Ampere-Hour Capacity of Lead Battery with Discharge Rate 

plate to the other, as in the ordinary electrolytic cell, commonly 
known as a primary battery. Therefore, the specific gravity of 
the electrolyte does not change with the state of charge and, con- 
sequently, the only direct way to measure the state of charge is 
with an ampere-hour meter, the hydrometer being of no use. But 
the loss of capacity due to high discharge rates is not a character- 
istic of the alkaline cell as it is with the lead type, so that an 
Edison battery does not require a compensated meter as just 
described. However, the drop in voltage of the Edison cell under 
high discharge rates is such that, from the user's viewpoint, the 
result is practically the same as with the lead-plate cell. 

Digitized by VjOOQIC 



GLOSSARY 



897 



Digitized by VjOOQIC 



GLOSSARY 



THE following glossary of automobile terms is not intended in any sense 
as a dictionary and only words used in the articles themselves have been 
defined. The definitions have been made as simple as possible, but if 
other terms unfamiliar to the reader are used, these should be looked up in order 
to obtain the complete definition. 



A. A.* A.: Abbreviation for American Auto- 
mobile Association. 

Abrasive: Any hard substance used for 
grinding or wearing away other substances. 

Absorber, Shock: See "Shock Absorber". 

Accelerate: To increase the speed. 

Acceleration: The rate of change of velocity 
of a moving body. In automobiles, the ability 
of the car to increase in speed. Pickup. 

Accelerator: Device for rapid control of the 
speed for quick opening and closing of the 
throttle. Usually in the form of a pedal, 
spring returned, the minimum throttle open- 
ing being controlled by the setting of the 
hand throttle. 

Accessory: A subordinate machine that 
accompanies or aids a more important 
machine; as, a horn is an accessory of an 
automobile. 

Accumulator: A secondary battery or 
storage battery- It usually consists of 
chemically prepared lead plates combined 
with an acid solution. Upon being charged 
with an electric current from a primary 
source, a chemical change takes place which 
enables the plates in their turn to give a 
current of electricity when used as a source 
of power, the plates at the same time return- 
ing to their original chemical state. 

Acetone: A liquid obtained as a by-product 
in the distillation of wood alcohol, and used 
in connection with reservoirs for storing 
acetylene for automobile lights, as it dis- 
solves many times its own volume of acety- 
lene gas. 

Acetylated Alcohol: Alcohol which has been 
denatured by the addition o' acetylene, 
which also increases its fuel value. See 
"Alcohol, Denatured". 

Acetylene: A gaseous hydrocarbide used as 
an illuminant; is usually generated for that 
purpose by the action of water on calcium 
carbide. 

Acetylene Generator. A closed vessel in 
which acetylene gas may be produced by the 
action of water on calcium carbide and which 
supplies the gas under uniform pressure. 

Acetylene Lamp: A lamp which burns 
acetylene gas. 

Ace ty lite: Calcium carbide which has been 
treated with glucose. It is used to obtain 
a more uniform and slower production of 
acetylene gas than can be obtained with the 
untreated calcium carbide. 



Acid: In connection with automobiles the 
term usually means the liquid or electrolyte 
used in the storage battery. See "Electro- 
lyte". 

Acid Cure. Method of rapid vulcanization 
of rubber without heat. Used in tire repairs. 
The agent is sulphur chloride. 

Acid i meter. An instrument for determining 
the purity of an acid. 

Active Material: Composition in grids that 
forms plates of a storage battery. It is this 
material in which the chemical changes occur 
in charging and discharging. 

Adapter: Device by which one type of lamp 
burner may be used instead of the one for 
which the lamp was designed. Usually a 
fitting by which a gas or oil lamp may be 
converted into an electric lamp. 

Adhesion: That property of surfaces in con- 
tact by virtue of which one of them tends 
to stick to the other. It is used as synony- 
mous with friction. The adhesion of wheels 
acts to prevent slipping. 

Adjustment: The slackening or tightening 
up of parts to compensate for wear, reduce 
friction, or secure better contact. 

Admission: In a steam engine, the letting 
in of the steam to the cylinder; in gas engine, 
the letting in of mixture of gas and air to the 
cylinder. 

Advanced Ignition: Usually called advanc- 
ing the spark. Setting the spark of an inter- 
nal-combustion motor so that it will ignite 
the charge at an earlier part of the stroke. 

Advance Sparking: A method by which the 
time of occurrence of the ignition spark may 
be regulated, by completing the electric 
circuit at the earlier period. 

Advancing the Spark: See "Advanced Ig- 
nition". 

Aerodynamics: The science of atmospheric 
laws, i.e., the effects produced by air in 
motion. 

After-Burning: Continued burning of the 
charge in an internal-combustion engine 
after the explosion. 

After-Firing: An explosion in the muffler or 
exhaust passages. 

A-h: Abbreviation for ampere hour. 

Air Bottle: A portable container holding 
compressed air or carbon dioxide for tire 
inflation. 

Air-Bound : See "Air Lock". 



399 



Digitized by 



Google 



GLOSSARY 



Air Compressor: A machine for supplying 
air under pressure lor inflating tires, starting 
the motor, etc. 

Air Cooled: Cooled by air direct. Usually 
referring to the cylinder of an engine, whose 
heat caused by the combustion within it 
is carried away by air convection and radia- 
tion. 

Air Cooling: A system of dispersing by air 
convection the heat generated in the cylinder 
of an internal-combustion motor. 

Air Intake: 

admit air. 



An opening in a carbureter to 



Air Leak: Entrance of air into the mixture 
between carbureter and cylinder. 

Air Lock: Stoppage of circulation in the 
water or gasoline system caused by a bubble 
of air lodging in the top of a bend in the 
pipe. 

Air Pump: A pump operated by the engine 
or by hand to supply air pressure to the oil 
tank or gasoline tank; sometimes called 
pressure pump. 

Air-Pump Governor: A device to regulate 
the speed of the air pump so as to give a 
uniform air pressure. 

Air Resistance: The resistance encountered 
by a surface in motion. This resistance in- 
creases as the square of the speed, which 
makes it necessary to employ four times as 
much power in order to double a given speed. 

Air Tube: See "Pneumatic Tire". 

Airless Tire: Name of special make of non- 
puncturable resilient tire. 

A. L. A. M.: Abbreviation for Association 
of Licensed Automobile Manufacturers, now 
out of existence. 

A. L. A. M. Horsepower Rating: The horse- 
power rating of an automobile found by the 
standard horsepower formula approved by 
the Association of Licensed Automobile 
Manufacturers. Since the dismemberment 
of this organization, the formula is usually 
call 2d the S.A.E. rating. This formula is 
h.p. = bore of cylinder (in inches) squared X 
No. of oylinders-f-2 . 5, at a piston speed of 
1000 r.p.m. 

Alarm, Low-Water: See "Low-Water 

Alarm". 

Alcohol: A colorless, volatile, inflammable 
liquid which may be used as fuel for internal- 
combustion engines. 

Alcohol, Denatured: Alcohol rendered unfit 
for drinking purposes by the addition of 
wood alcohol, acetylene, and other sub- 
stances. 

Alignment: The state of being exactly in 
line. Applied to crankshafts a~d transmis- 
sion shafts and to the parallel conditions of 
the front and rear wheels on either side. 

Alternating Current: Electric current 
which alternates in direction periodically. 

Ammeter: An instrument to measure the 
values of current in an electric circuit directly 
in amperes. Also called ampere meter. 

Amperage: The number of amperes, or cur- 
rent strength, in an electric circuit. 

Ampere: The practical unit of rate of flow 
of electric current, measuring the current 
intensity. 

Ampere Hour: A term used to denote the 
capacity of a storage battery or closed-circuit 
primary battery. A battery that will deliver 



three amperes for six hours is said to have an 

eighteen-ampere-hour capacity. 
Ampere Meter: See "Ammeter". 
Angle-Iron Underframe: An underframe 

constructed of steel bars whose cross section 

is a right angle. 
Anneal : . To make a metal soft by heating and 

cooling. To draw the temper of a metal. 
Annular Gear: A toothed wheel upon which 

the teeth are formed on the inner circum- 
ference. 
Annular Valve: A circular valve having a 

hole in the center. 

Annunciator: An installation of electric 
signals or a speaking tube to allow the pas- 
sengers in an enclosed car to communicate 
with the driver. 

Anti-Freezing Solution: A solution to be 
used in the cooling system to prevent freezing 
in cold weather; any harmless solution whose 
freezing point is somewhat below that of 
water may be used. 

Anti-Friction Metal: Various alloys of tin 
and lead used to line bearings, such as Babbitt 
metal, white metal, etc. 

Anti-Skid Device: Any device which may 
be applied to the wheels of a motorcar to 
prevent their skidding, such as tire coverings 
with metal rivets in them, chains, etc. 

Apron: Extensions of the fenders to prevent 
splashing by mud or road dirt. 

Armature: In dynamo-electric machines, 
the portion of a generator in which the 
current is developed, or in a motor, the por- 
tion in which the current produces rotation. 
In most generators in automobile work, the 
armature is the rotating portion. In mag- 
netic or electromagnetic machines the arma- 
ture is the movable portion which is attached 
to the magnetic poles. 

Armature Core: The iron portion of the 
armature which carries the windings and 
serves as part of the path for the magnetic 
flux. 

Armature Shaft: The shaft upon and with 
which the armature rotates. 

Armature Winding: Electrical conductors, 
usually copper, in an armature, and in which 
the current is generated, in case of a gen- 
erator, or in which they produce rotation in 
a motor. 

Artillery Wheel : A wheel having heavy wood 
spokes. 

Aspirating Nozzle: An atomising nozzle to 
make the liquid passing through it pass from 
it in the form of a spray. 

Assembled Car: A car whose chief parts, 
such as engine, gearset axles, body, etc., are 
manufactured by different parts makers, 
only the final process of putting them to- 
gether being carried out in the car-making 
plant. 

Atmospheric Line: A line drawn on an in- 
dicator diagram at a point corresponding 
with the pressure of the atmosphere. 

Atmospheric Valve: See "Suction Valve". 

Atomizer: A device by which a liquid fuel, 
such as gasoline, is reduced to small particles 
or to a spray; usually incorporated in the 
carbureter. 

Auto: (1) Popular abbreviation for auto- 
mobile. (2) A Greek prefix meaning self. 



400 



Digitized by 



Google 



GLOSSARY 



Auto-Bus: An enclosed motor-driven public 
conveyance, seating six or more people; 
usually has a regular route of travel. 

Autocar: A motorcar or automobile; a trade 
name for a particular make of automobile. 

Auto-Cycle: See "Motorcycle". 

Autodrome: A track especially prepared for 
automobile driving, particularly for races. 

Autogenous Welding: See "Welding, Autog- 
enous". 

Auto-Igniter: A small magneto generator 
or dynamo for igniting gasoline engines, the 
armature of which is connected with the 
flywheel by gears or by friction wheels, so 
that electric current is supplied as long as 
the engine revolves. 

Autolst: One who uses an automobile. 

Automatic Carbureter: A vaporizer or car- 
bureter for gasoline engines whose action is 
entirely automatic. 

Automatic Cut-Out: See "Cut-Out, Auto- 
matic". 

Automatic Spark Advance: Automatic 
variation of the instant of spark occurrence 
in the cylinder. Mechanical advancing and 
retarding of the spark to correspond with and 
controlled by variations in crankshaft speed. 

Auto-Meter: Trade name for special make 
of combined speedometer and odometer. 

Automobile: A motor-driven vehicle having 
four or more wheels. Some three-wheeled 
vehicles are prooerly automobiles, but are 
usually called tricars. 

Automobillst: The driver or user of an auto- 
mobile. 

Auto Truck: A motor-driven vehicle for 
transporting heavy loads; a heavy com- 
mercial car. 

Auxiliary Air Valve: Valve controlling the 
admission of air through the auxiliary air 
intake of a carbureter. 

Auxiliary Air Intake: Opening through 
which additional air is admitted to the car- 
bureter at high speeds. 

Auxiliary Exhaust: Ports cut through cyl- 
inder walls to permit exhaust gases to be 
released from the cylinder when uncovered 
by the piston. These are sometimes used 
as an additional scavenging means for the 
regular exhaust valves. 

Auxiliary Fuel Tank: See "Fuel Tank, 
Auxiliary". 

Auxiliary Spark Gap: See "Spark Gap, 
Outside". 

Axle : The spindle with which a wheel revolves 
or upon which it revolves. 

Axle, Cambered: An axle whose ends are 

slanted downwards to camber the wheels. 
Axle, Channel: An axle which is U-shaped 

in cross section. 
Axle, Dead: Solid, fixed, stationary axle. 

An axle upon which the wheels revolve but 

which itself does not revolve. 
Axle, Dropped: An axle in which the central 

portion is on a lower level than the ends. 
Axle, Floating: A full-floating axle. A live 

axle in which the shafts support none of the 

car weight, but serve only to turn the wheels. 
Axle, f-Beam: An axle whose cross section 

is in the shape of the letter I. 
Axle, Live: An axle in which are comprised 



the driving shafts that carry the power of the 
motor tp the driving wheels. 
Ax-le, Semi-Floating: A live axle in which 
the driving shafts carry a part of the car 
weight as well as transmitting the driving 
torque. 

Axle, Three-Quarters Floating: A live 
axle in which the shafts carry a part of the 
weight of the car, but less than that carried 
by the semi-floating axle. It is inter- 
mediated by a floating axle and the semi- 
floating axle. 

Axle, Trussed: An axle in which downward 
bending is prevented by a truss. 

Axle, Tubular: An axle formed of steel tub- 
ing. Usually applied to the front axles, but 
sometimes used in referring to tubular shafts 
of rear axles. 

Axle Casing: That part of a live axle that 
encloses the driving shafts and differential 
and driving gears. Axle housing. 

Axle Housing: See "Axle Casing". 

Axle Shaft: The member transmitting the 
driving torque from the differential to the 
rear wheels. 

B 

Babbitt: A soft metal alloy used for lining 
the bearings of shafts. 

Back-Firing: An explosion of the mixture 
in the intake manifold or carbureter caused 
by the communication of the flame of ex- 
plosion in the cylinders. Usually due to too 
weak a mixture. Popping. 

Back Kick: The reversal of direction of the 
starting, caused by back-firing. 

Backlash: The play between a screw and nut 
or between the teeth of a pair of gear wheels. 

Back Pressure: Pressure of the exhaust 
gases due to improper design or operation of 
the exhaust system. 

Baffle Plate: A plate used to prevent too 
free movement of a liquid in the container. 
In a gas engine cylinder, a plate covering the 
lower end of the cylinder to prevent too 
much oil being splashed into it. The plate 
has a slot through which the connecting rod 
may work. 

Balance Gear: See "Differential Gear". 

Balancing of Gasoline Engines: Insuring 
the equilibrium of moving parts to rcdi 3e 
the vibration and shocks. 

Ball-and-Socket Joint: A joint in wb h a 
ball is placed within a socket recessed o fit 
it, permitting free motion in any uir ction 
within limits. 

Ball Bearing: A bearing in which the rotat- 
ing shaft or axle is carried upon a number of 
small steel balls which are free to turn in 
annular paths, called races. 

Balladeur Train: A French name for a slid- 
ing change-speed gear. 

Barking: The sound made by the explosions 
caused by after-firing. 

Base Bearing: See "Main Bearing". 

Base Explosion: See "Crankcase Explosion". 

Battery: A combination of primary or 
secondary cells, as dry cells or storage cells. 

Battery, Dry: See "Dry Battery". 

Battery, Storage: See "Accumulator". 

Battery Acid: The electrolyte in a storage 
battery. 



401 



Digitized by 



Googk 



GLOSSARY 



Battery-Charging flug: Power terminals 
to which the leads of a storage battery may 
be connectec for charging the battery. 

Battery Gage: (1) Voltmeter or ammeter 
or voltammeter for testing the specific 
gravity of the electrolyte in a secondary 
battery. 

Battery Syringe: A syringe used to draw out 
a part of the electrolyte or solution from a 
storage battery cell to test its density and 
specific gravity. 

Baume: A scale indicating the specific 
gravity or density of liquids and having 
degrees as units. Gasoline of a specific 

gavity of .735 has a gravity of 61 degrees 
aume\ 

Bearing: A support of a shaft upon which it 
may rotate. 

Bearing, Annular Ball: A ball bearing con- 
sisting of two concentric rings, between 
which are steel balls. 

Bearing, Ball: A bearing in which the 
rotating shaft and the stationary portion of 
the bearings are separated from sliding con- 
tact by steel balls. A steel collar fitted to 
the shaft rolls upon the balls, which in turn 
roll upon steel cc liar attached to the station- 
ary portion of the bearing. 

Bearing, Gup and Gone: A ball bearing in 
which the balls roll in a race, which is formed 
between a cone-shaped fixed collar and a 
cup-shaped shaft collar. 

Bearing, Main: The bearing in which 
rotates the crankshaft of an engine. 

Bearing, Plain: A bearing in which the 
rotating shaft is in sliding contact with the 
bearing supporting it. 

Bearing, Radial: A bearing designed to 
resist loads from a direction at right angles 
to the axis of the shaft. 

Bearing, Roller: A bearing in which the 
journal rests upon, and is surrounded by, 
hardened steel rollers which revolve in a 
channel or race surrounding the shaft. 

Bearing, Thrust: A bearing designed to 
resist loads or pressures parallel with the 
axis of the shaft. 

Bearing Cap: That portion of a plain bear- 
ing detachable from the stationary portion, 
and which holds the bearing bushing and 
shaft. 

Bearing Surface: The projected area of a 
bearing in a perpendicular plane to the 
direction of pressure. 

Beau de Rochas Cycle: The four-stroke 
cycle used in most internal-combustion 
engines. This cycle was proposed by M. 
Beau de Rochas and put into practical form 
by Dr. Otto. See "Four-Cycle". 

Belt and Clutch Dressing: A composition 
to be applied to belts and clutches to prevent 
them from slipping. 

Belt Drive: A method of transmitting power 
from the engine to the countershaft or jack 
shaft by means of belts. 

Benzine: A petroleum product having a 
specific gravity between that of kerosene and 

Sasoline. Its specific gravity is between 60 
egrees and 65 degrees Baume*. 

Benzol: A product of the distillation of coal 
tar. Coal tar benzine. Used as a rubber 
solvent and in Europe as a motor fuel. 

Berline Body: A limousine automobile body 
having more than two seats in the back part. 



Bevel-Gear: Gears the faces of whose teeth 
are not parallel with the shaft, but are on a 
beveled edge of the gear wheel. 

Bevel-Gear Drive: Method of driving one 
shaft from another at an angle to the first. 
The chief method of transmitting the drive 
from the propeller shaft to the rear axle 
shafts. 

B. H. P.: An abbreviation for brake horse- 
power. 

Bicycle: A two-wheeled vehicle propelled by 

the pedaling of the rider. 
Binding Posts: See "Terminals". 
Bleeder: A by-pass in the' sight-feed of a 

mechanical oiling system by which the oil 

delivered through that feed is allowed to 

pass out instead of going to the bearings. 
Blister: A defect in tires caused by the 

separation of the tread from the fabric. 
Block Chain: A chain used in automobiles, 

bicycles, etc., of which each alternate link 

is a steel block. 

Blow-Back: The backward rushing of the 
fuel gas through the inlet valve into the 
carbureter. 

Blower Cooled: A gas engine cooled by 
positive circulation of air maintained by a 
blower. 

Blow-Off: A blow-out caused by the edge of 
the bead of tire becoming free from the rim 
and allowing the tube to protrude through 
the space thus formed. 

Blow-Out: The rupture of both the inner 
tube and outer casing of a pneumatic tire. 

Blow-Out Patch: See "Patch, Tire Repair". 

Body: (1) The superstructure of an auto- 
mobile; the part that resembles and repre- 
sents the body of a horse-drawn vehicle. 
(2) In oils, the degree of viscosity. The 
tendency of drops of oils to hang together. 

Body Hangers: Attachments to or exten- 
sions of the frame for holding the body of the 
vehicle. They should be properly called 
frame hangers. 

Boiler: A vessel in which water is evaporated 
into steam for the generation of power. 

Boiler, Fire-Tube: A tubular steam boiler 
in which the end plates are connected by a 
number of open ended thin tubes, the spaces 
around which are filled with water, the hot 
gases passing through the tubes. 

Boiler, Flash : A steam boiler in which steam 
is generated practically instantaneously. 
There is practically no water or steam stored 
in the boiler. A flash generator. 

Boiler, Water-Tube: A steam boiler in 
which the water is carried in metal tubes, 
around which the hot gases circulate. 

Boiler Alarm: See "Low- Water Alarm". 

Boiler Covering: A non-conducting sub 
stance used as a covering for boilers to pre- 
vent loss of heat by radiation. 

Boiler-Feed Pump: An automatic and self- 
regulating pump for supplying a boiler with 
feed water. 

Boiler-Feed Regulator: A device to make 
the feed-water Bupply of the boiler auto- 
matic. 

Bonnet: (1) The hood or metallic cover 
over the front end of an automobile. See 
"Hood". (2) The cover over a pump- 
valve box, or a slide-valve casing. <3) A 
cover to enclose and guide the tail end of a 



402 



Digitized by 



Google 



GLOSSARY 



steam-engine-valve spindle or the cover of a 
piston- valve casing. (4) The pan under- 
neath the engine in an automobile. 
Boot: A covering to protect joints from dirt 
and water or to prevent the leakage of grease. 
(2) Space provided for baggage at the rear 
of a car. 

Bore: The inside diameter of the cylinder. 

Boss: m An enlarged portion of a part to give 
a point for attachment of another part. 

Bottom: The meshing of gears without 
clearance. 

Bow Separator: A part to prevent chafing 
of the bows of a top when folded. 

Boyle's Law of Gases: A law defining the 
volume and pressure of gases at constantly 
maintained temperatures. It states that 
the volume of a gas varies inversely as the 
pressure so long as the temperature remains 
the same; or, the pressure of a gas is propor- 
tional to its density. 

Brake: An apparatus for the absorption of 
power by friction, and by clamping some por- 
tion of the driving mechanism to retard or 
stop the forward motion of the car. 

Brake* Air-Cooled : A brake whose parts are 
ridged to present a large surface for trans- 
ferring to tne air the frictional heat generated 
in them. 

Brake, Band: A brake which contracts 
upon the outside of a drum attached to some 
part of the driving mechanism. 

Brake, Constricting Band : A form of brake 
applied by tightening a band around a pulley 
or drum. 

Brake, Differential: A brake acting upon 
the differential gear. 

Brake, Double- Acting: A brake which will 
hold when the drum is rotating in either 
direction. 

Brake, Drum, and Band: See "Brake, 
Band". 

Brake, Emergency: A brake intended to be 
used in case the service brake does not act 
to a sufficient extent. 

Brake, Expanding-Band: A drum brake in 
which the braking force is exerted by a band 
forced outward against the inner rim of a 
pulley. 

Brake, External-Contracting: A brake 
consisting of a drum affixed to a rotating 

Eart, the outer surface of whieh is encircled 
y a contracting band. 

Brake, Foot: A brake designed to be oper- 
ated by the driver's foot. A pedal brake. 
Usually the service brake. 

Brake, Front-Wheel: A brake designed to 
operate on the front wheels of the car. 

Brake, Gearset: A brake designed to act on 
the transmission shaft and attached to the 
gearbox. 

Brake, Hand: A brake designed to be oper- 
ated by means of a hand lever. Usually th© 
emergency brake. 

Brake, Hub: A brake consisting of a drum 
secured to one of the wheels. This is the 
usual type. 

Brake, Internal: A brake in which an ex- 
panding mechanism is contained within a 
rotating drum, the expansion bringing pres- 
sure to bear on the drum. 

Brake, Internal-Expanding: A brake con- 
sisting of a drum, against the inside of which 
may be expanded a band or a shoe. 



Brake, Motor: A brake in an electric vehicle 
which acts upon the armature shaft of the 
motor. 

Brake, Service: A brake designed to be used 

in ordinary driving. It is usually operated 

by the driver's foot. 
Brake, Shoe: A brake in which a metal shoe 

is clamped against a revolving wheel. 
Brake, Transmission: A brake designed to 

act upon the transmission shaft. 
Brake, Water-Cooled : A brake through 

which water may be circulated to carry off 

the frictional heat. 
Brake Equalizer: A mechanism applied to a 

system of brakes operated in pairs to assure 

that each brake shall be applied with equal 

force. 

Brake Horsepower: The horsepower sup- 
plied by an engine as shown by the applica- 
tion of a brake or absorption dynamometer. 

Brake Housing: A casing enclosing the 
brake mechanism. 

Brake Lever: The lever by which the brake 
is applied tc the wheel. 

Brake Lining: The wearing surface of a 
brake ; usually arranged to be easily replaced 
when worn. 

Brake Pedal: Pedal by which the brake is 
applied. 

Brake Pull Rod: A rod transmitting the 
tension from the lever or pedal to the mova- 
ble portion of the brake proper. 

Brake Ratchet : A device by which the brake 
lever or brake pedal can be set in position and 
retained there ; usually consists of a notched 
quadrant with which a movable tongue on 
the lever head or pedal engages. 

Brake Rod: The rod connecting the brake 
lever with the brake. 

Brake Test: A test of a motor by means of a 
dynamometer to determine its power output 
at different speeds. 

Braking Surface: The surface of contact 
between the rotating and stationary parts of 
a brake. 

Braze: To join by brazing. 

Brazing: The process of permanently joining 
metal parts by intense heat. 

Breaker Strip: A strip of canvas placed 
between the tread and body of an outer tire 
casing to increase the wearing qualities. 

Breather: An opening in the crankcase of a 
gas engine to permit pressure therein to 
remain equal during the movement of the 
pistons. 

British Thermal Unit. The ordinary unit of 
heat. It is that quantity of heat required to 
raise the temperature of one pound of pure 
water one degree Fahrenheit at the tempera- 
ture of greatest density of water. 

Brougham Body: A closed-in automobile 
body having windows at the side doors, and 
in front, but with no extension of the roof 
over the front seat. 

Brush Holder: In electrical machinery, an, 
arrangement to hold one end of a connection 
flexible in contact with a moving part of the 
circuit. 

B. T. U.: Abbreviation for British Thermal 
Unit. 

Buckboard : A four-wheeled vehicle in which 
the body and springs are replaced by ao 
elastic board or frame 



403 



Digitized by 



Google 



GLOSSARY 



Buckling: Irregularities in the shape of the 
plates of storage cells following a too rapid 
discharge. 

Bumper: (1) A contrivance at the front of 
■ the car to minimise shock of collision; it con- 
sists of plungers working in tubes and gain- 
ing elasticity from springs. (2) A bar placed 
across the end of a car, usually the front 
end, to take the shock of collision and thus 
prevent damage to the car itself. A rubber 
or leather pad interposed between the axle 
and frame of a car. 

Burner, "Torch** Igniter: A movable auxil- 
iary vaporizer for starting the fire in steam 
automooile burners. 

Bushing: A bearing lining. Usually made 
of anti-friction metal and capable of adjust- 
ment or renewal. 

Bus-Pipe: A manifold pipe. 

Butterfly Valve: A valve inserted in a pipe, 
usually circular and of nearly the same 
diameter as the pipe, designed to turn upon 
a spindle through its diameter and thus shut 
off or permit flow through the pipe. Usually 
employed for throttle valves and carbureter 
air valve . 

Buzzer: (1) A name sometimes applied to 
the vibrator or trembler of a jump-spark 
ignition coil. (2) A device used in place 
of a horn, and consisting of a diaphragm 
which is made to vibrate rapidly by an 
electromagnet. 

By-Pass: A small valve to provide a second- 
ary passage for fluids passing through a 
system of piping. 



G: Abbreviation for a centigrade degree of 
temperature. 

Calcium Carbide: A compound of calcium 
and carbon used for the generation of acety- 
lene by the application of water. 

Calcium Chloride: A salt which dissolved 
in water is used as an anti-freezing solution. 

Cam: A revolving disk, irregular in shape, 
fixed on a revolving shaft so as to impart to 
a rod or lever in contact with it an intermit- 
tent or variable motion. 

Cam, Exhaust: A cam designed to operate 
the exhaust of an engine. 

Cam, Ignition: A cam designed to operate 
the ignition mechanism. In magnetos it 
operates the make-and-break devioe. 

Cam, Jnlet: A cam designed to operate the 
inlet valve of an engine. 

Camber: (1) The greatest depth of curva- 
ture of a surface. (2) The amount of 
bend in an axle designed to incline the 
wheels. 

Camber of Spring: The maximum distance 
between the upper and lower parts of a 
spring under a given load. 

Cambered Frame: A narrowing of the front 
of a motor car to permit of easier turning. 

Cam Gear: The gear driving the camshaft 
of a gas engine. In a four-cycle engine this 
is the same as the two-speed gear. 

Camshaft: A shaft by which the valve came 
are rotated; also known as the secondary shaft. 

Camshaft, Overhead: The camshaft carried 
along or above the cylinder heads, to operate 
overhead valves. 

Camshaft Gears: The gears or train of 
gears by which the camshaft is driven from 



the crankshaft. Half-time gears, timing 

gears, distribution gears. 
Canopy: An automobile top that can not be 

folded up. 
Capacity of a Condenser: The quality of 

electricity or electrostatic charge. Of a 

storage battery, the amount of electricity 

which may be obtained by the discharge of 

a fully charged battery. Usually expressed 

in ampere hours. 
Cape Hood:* An automobile top which is 

capable of either being folded up or extended. 
Car: A wheeled vehicle. 
Carbide: See "Calcium Carbide". 
Carbide Feed: A type of acetylene generator 

in which the calcium carbide is fed into the 

water. 

Carbon Bridge: Formation of soot between 
points of spark plug. 

Carbon Deposit: A deposit upon the inte- 
rior of the combustion chamber of a gasoline 
engine composed of carbonaceous particles 
from the lubricating oil, too rich fuel mix- 
ture, or road dust. 

Carbon Remover: A tool or solution for 
removing carbon deposits from the cylinder, 
piston, or spark plug of a gasoline engine. 

Carbonization: The deposit of carbon. 

Carbureter: An appliance for mixing an 

inflammable vapor with air. It allows air 

' to be passed through or over a liquid fuel 

and to carry off a portion of its vapor mixed 

with the air, forming an explosive mixture. 

Carbureter, Automatic: A carbureter so 
designed that either the air supply alone or 
both the air and gasoline supplies are regu- 
lated automatically. 

Carbureter, Constant-Level: A carbureter 
the level of the gasoline in which is main- 
tained automatically at a constant height. 
A float-feed carbureter. 

Carbureter, Exhaust -Jacketed: A carbu- 
reter whose mixing chamber is heated by the 
circulation of exhaust gas. 

Carbureter, Multiple- Jet: A carbureter 
having more that one spray nozzle or jet. 

Carbureter, Water-Jacketed : A carbureter 
whose mixing chamber is heated by the cir- 
culation of water from the cooling system. 

Carbureter Float: A buoyant part of the 
carbureter designed to float in the gasoline 
and connected to a valve controlling the 
flow from the 'uel tank, designed to main- 
tain automatically a constant level of the 
gasoline in the flow chamber. 

Carbureter Float Chamber: A reservoir 
containing the float and in which a con- 
stant level of fuel is maintained. 

Carbureter Jet: The opening through which 
liquid fuel is ejected in a spray from the 
standpipe of a carbureter nozzle. 

Carbureter Needle Vaive: A valve control- 
ling t]ae flow of fuel from the flow chamber 
to the standpipe. 

Carbureter Nozzle: See "Carbureter Jet'*. 

Carbureter Standpipe: A vertical pipe 
carrying the nozzle. 

Carburetion: The process of mixing hydro- 
carbon particles with the air. The action in 
a carbureter. 

Cardan Joint: A universal Joint or Hooke'a 
coupling. 



404 



Digitized by 



Google 



GLOSSARY 



Cardan Shaft: A shaft provided with a 
Cardan joint at each end. 

Casing: The shoe or outer covering of a 
double-tube automobile tire. 

Catalytic Ignition: See "Ignition, Catalytic". 

Cell: One of the units of a voltaic battery. 

Cell, Dry: See "Dry Cell". 

Cell, Storage: See "Accumulator". 

Cellular Radiator: A radiator in which the 
openings between the tubes are in the form 
of small cells. The same as a honeycomb 
radiator. 

Cellular Tire : A cushion tire which is divided 
into compartments or cells. 

Center of Gravity: That point in a body, 
which, if the body were suspended freely in 
equilibrium, would be the point of applica- 
tion of the resultant forces of gravity acting 
upon the body. 

Center Control: The location of the gear- 
shift and emergency brake levers of a car in 
the center of a line parallel to the front of 
the front seat. 

Centigrade Scale: The thermometer scale 
invented by Celsius. Used universally in 
scientific work. 

Century. In automobiling, a hundred-mile 
run. 

C. G. S. System: Abbreviation for centi- 
meter-gram-second system of measurement; 
the standard system in scientific work. . 

Chain, Drive: A heavy chain by which the 
power from the motor may be transmitted 
to the rear wheels of an automobile. 

Chain, Roller: A sprocket chain, the cross 
bars of whose links are rollers. 

Chain, Silent: See "Silent Chain". 

Chain, Tire: A small chain fastened about 
the tire to increase traction and prevent 
skidding. 

Chain Wheel: A sprocket wheel for the 
transmission chains of a motor-driven 
vehicle. 

Change-Speed Gear: See "Gear, Change- 
Speed". 

Change-Speed Lever: See "Lever, Change- 
Speed". 

Charge: The fuel mixture introduced into 
the cylinder of a gas engine. The act of 
storing up electric energy in an accumulator. 

Charging: The passing of a current of elec- 
tricity through a storage cell. 

Charles* Law of Gases: See "Gases, Gay 
Lussac's Law of". 

Chassis. The mechanical features of a motor 
car assembled, but without body, fenders, or 
other superstructure not essential to the 
operation ,of the car. 

Chauffeur: In America this term means the 
paid driver or operator of a motor car. The 
literal translation from the French means 
stoker or fireman of a boiler. 

Check. Steering: See "Steering Check". 

Check Valve: An automatic or non-return 
valve used to control the admission of feed 
water in the boiler, etc. 

Choke: The missing of explosions or poor 

explosions due to too rich mixture. 
Circuit, Primary: See "Prhnary Circuit". 

Circuit, Secondary: See "Secondary Cir* 
o\iit'\ 



Circuit Breaker: A device installed in an 
electric circuit and intended to open the 
circuit automatically under predetermined 
conditions of current flow. 

Circulating Pump: A pump which keeps a 
liquid flowing through a series of pipes which 
provides a return circuit. t In a motor car, 
water and oil circulation is maintained by 
circulating pump. 

Circulation Pump: A mechanically oper- 
ated pump by which the circulation of water 
in the cooling system is maintained. 

Circulating System: The method or series 
of pipes through which a continuous flow of 
water or oil is maintained and in which the 
liquid is sent through the system over and 
over. 

Clash Gear: A sliding change-speed gear. 

Clearance: (1) The distance between the 
road surface and the lowest part of the 
under-body of an automobile. (2) The 
space between, the piston of an engine when 
at the extremity of its stroke, ana the head 
of the cylinder. 

Clearance, Valve: See "Valve Clearance". 

Clearance Space: The space left between 
the end of the cylinder and the piston plus 
the volume of the ports between the valves 
and the cylinder. 

Clevis: The fork on the end of a rod. 

Clevis Pin: The pin passing through the 
ends of a clevis and through the rod to which 
the clevis is joined. 

Clincher Rim : A wheel rim having a turned- 
in edge on each side, forming channels. ' Into 
this the edge or flange of the tire fits, the air 
pressure within locking the tire and rim 
together. 

Clincher Tire: A pneumatic tire design to 
fit on a clincher rim. 

Clutch: A device for engaging or discon- 
necting two pieces of shafting so that they 
revolve together or run free ar desired. 

Clutch Cone: A clutch whose engaging sur- 
faces consist of the outer surface of the 
frustrum of one cone and the inner surface 
of the frustrum of another. 

Clutch, Con f acting-Band: A clutch con- 
sisting at a drum and band, the latter con- 
tracting upon the former. 

Clutch, Pry-Plate: A clutch whose friction 
■urfaces are metal plates, not lubricated. . 

Clutch, Expanding-Band: A clutch consist- 
- ing of a drum and band, the latter expanding 
within the former. 

Clutch, Jaw: A clutch whose members lock 
end to end by projections or jaws in one 
entering corresponding depressions in the 
other. 

Clutch, Multiple-Disk: A clutch whose 
friction surfaces are metal plates or disks, 
alternate disks being attached to one mem- 
ber and the rest to the other member of the 
drive. 

Clutch Brake: A device designed to stop 
automatically the rotation of the driven 
member of a clutch after disengagement 
from the driving member. 

Clutch Lining: The wearing surface of a 
clutch. This may be easily removed and 
replaced when worn. 

Clutch Pedal: The pedal by which the 
clutch may be disengaged, engagement being 
obtained automatically by means of a spring. 



405 



Digitized by 



Google 



GLOSSARY 



Clutch Spring: A spring arranged to either 
hold a clutch out of gear or throw it into 
gear. 

Coasting: The movement of the car without 
constant applications of the motive power, 
as in running downhill with the aid of grav- 
ity or on the level, through the momentum 
obtained by previous power applications. 

Cock, Priming: A small cock, usually 
operated by a lever, for admitting gasoline 
to the carbureter to start its action. 

Coll, Induction: See "Spark Coil". 

Coll, Non-Vibrator: A coil so designed that 
it will supply a sufficient spark for the igni- 
tion with one make and break of the primary 
circuit. 

Coll, Primary: See "Primary Coil". 

Coil, Secondary: See "Secondary Spark 
Coil". 

Coll, Spark: See "Spark Coil". 

Coil, Vibrator: A spark coil with which is 
incorporated an electromagnetic vibrator to 
make and break the primary circuit. 

Coll Vaporizer: An auxiliary vaporizer to 
assist in starting a steam boiler. It is a coil 
of tubing into which liquid gasoline is ad- 
mitted and burned to start the generation of 
gas in the main burner. 

KJi^ld Teat: The temperature in degrees 
Fahrenheit at which a lubricant passes from 
the fluid to the solid state. 

Combustion Chamber: That part of an 
explosive motor in which the gases are com- 
pressed and then fired, usually by an electric 
spark. 

Combustion Space: See "Clearance" and 
"Clearance Space". 

Commercial Car: A motor-driven vehicle 
for commercial use, such as transporting 
passengers or freight. 

Commutator: In the ignition system of an 
explosive motor, the commutator is a device 
to automatically complete the circuit of 
each of a number of cylinders in succession. 

Commutator of Dynamo or Motor: That 
part of a dynamo which is designed to cause 
the alternating current produced in the 
armature to flow in one direction in the 
external circuit; in a motor, to change the 
direct current in the external circuit into 
alternating current. 

Compensating Carbureter: An automatic 
attachment to a carbureter controlling 
either air or fuel admission, or both, so that 
the proportion of one to the other is always 
maintained under any vibration of power 
required. 

Compensating Gear: See "Differential 
Gear". 

Compensating Joint: See "Universal 
Joint". 

Compound Engine: A multiple-expansion 
steam engine in which the steam is expanded 
in two stages, first in the high-pressure cyl- 
inder and then in the low-pressure cylinder. 

Compression: (1) That part of the cycle 
of a gas engine in which the charge is com- 
pressed before ignition; in a steam engine it 
is the phase of the cycle in which the pres- 
sure is increased, due to compression of the 
exhaust steam behind the piston. (2) The 
greatest pressure exerted on the gas in the 
compression chamber. 



Compression Chamber: The clearance vol- 
ume above the piston in a gas engine; also 
called "Compression Space". 

Compression Cock: See "Compression-Re- 
lief Cock". 

Compression Line: The line on an indi- 
cator diagram corresponding to the phase of 
the cycle in which the gas is compressed. 

Compression -Relief Cock: A small cock by 
which the compression chamber of an inter- 
nal-combustion motor may be opened to the 
air and thus allow the compression in the 
cylinder to be relieved to facilitate turning 
by hand, or cranking. 

Compression Space: See "Compression 
Chamber". 

Compression Tester: A small pressure gage 
by which the degree of compression of the 
mixture in a gas-engine cylinder may De- 
tested. 

Compressor, Air: See "Air Compressor". 

Condenser: (1) In a steam motor, an 
apparatus in which the exhaust steam is 
converted back into water. (2) A device 
for increasing the electric capacity of a 
circuit. Used in an ignition circuit to 
increase the strength of the spark. 

Cone Bearing: A shaft bearing in which the 
shaft is turned to a taper and the journal 
turned to a conical or taper form. 

Cone Clutch: A friction clutch in which 
there are two cones, on« fitting within the 
other. 

Connecting Rods: The part of an engine 
connecting the piston to the crank, and by 
means of which a reciprocating motion of 
the piston is converted into the rotary 
motion of the crank. 

Constricting Band Brake: See "Brake, 
Constricting Band". 

Constricting Clutch: A friction clutch in 
which a band is tightened around a drum to 
engage it. 

Contact Breaker: A device on some forms 
of gasoline motors having an induction coil 
of the single jump^spark type, to open and 
close the electric circuit of the battery and 
coil at the proper time for the passage of the 
arc or spark at the points of the^ spark plug. 

Contact Maker: See "Contact Breaker". 

Continental Drive: Double-chain drive. 

Control: The levers, pedals, etc., in general 
with the speed and direction of a car is regu- 
lated by the driver. In speaking of rignt, 
left, or center control, the gearshift and 
emergency brake levers only are meant. 

Control, Spark: Method of controlling the 
power of an engine by varying the point in 
the stroke at which ignition takes place. 

Control, Throttle: Method of governing 
the power of the engine by altering the area 
of the passage leading to the admission 
valve so that the amount of the fuel intro- 
duced into the cylinder is varied. 

Controller, Electric: Apparatus for secur- 
ing various combinations of storage cells and 
of motors so as to vary the speed of the car 
at will. 

Converter: A device for changing alternat- 
ing current into direct current for charging 
storage batteries, etc. Converters may be 
any of three kinds: rotary, electrolytic, or 
mercury-vapor. The mercury-vapor con- 
verter is most widely used. 



406 



Digitized by 



Google 



GLOSSARY 



Convertible Body: An automobile body 
which may be used in two or more ways, 
usually as an open or closed carriage, or in 
which several seats may be concealed, and 
raised to increase the seating capacity. 

Cooling Fan: Fan used in automobiles to 
increase the current of air circulating around 
the cylinders, or through the radiator. 

Pooling System: The parts of a gas engine 
or motor car by which the heat is generated in 
the cylinder by the combustion of the fuel 
mixture. See "Water Cooling" and "Air 
Cooling". 

Cork Inserts: Pieces of cork inserted in 
friction surfaces of clutches or brakes to 
give softer action. 

Cotter Pin: A split metal pin designed to 
pass through holes in a bolt and nut to hold 
the former in place. 

Coulomb: The unit of measure of electrical 
quantity. Sometimes called "Ampere Sec- 
ond". It is equivalent to the product of 
the current in amperes by the number of 
seconds current has been flowing. 

Counterbalance: Weights attached to a 
moving part to balance that part. 

Countershaft : An intermediate or secondary 
shaft in the power-transmission system. 

Coupe: An enclosed body seating one or two 
passengers and the driver, all within. 

Coupling, Flexible: See "Universal Joint". 

Cowl: That portion of the body of the car 
which forms a hood over the instrument 
board or dash. 

Cowl Tank: A fuel tank carried under the 
cowl and immediately in front of the dash. 

Crank: A lever designed to convert recipro- 
cating motion into rotating motion or vice 
versa; usually in the form of a lever formed 
at an angle with the shaft, and connected 
with piston by means of connecting rod. 

Crank, Starting: A handle made to fit the 
projecting end of the crankshaft of a gas 
engine, so that the engine may be started 
revolving by hand. 

Crankcase: The casing surrounding the 
crank end of the engine. 

Crankcase Explosion: Explosion of un- 
burned gases in the crankcase. 

Crank Chamber: The enclosed space of 
small engines in which the crank works. 

Cranking: The act of rotating the motor by 
means of a handle in order to start it. Turn- 
ing the flywheel over a few times causes the 
engine to take up its cycle, and after an 
explosion it continues to operate. 

Crankpin : The pin by which the connecting 
rod is attached to the crank. 

Crankshaft: The main shaft of an engine. 

Crankshaft, Offset: A crankshaft whose 
center line is not in the same plane as the 
axis of its cylinders. 

Creeping of Pneumatic Tires: The tend- 
ency of pneumatic tires to push forward 
from the ground, and thus around the rim, in 
the effort to relieve and distribute the 
pressure. 

Cross Member: A structural member of the 
frame uniting the side members. 

Crypto Gear: See "Planetary Gear". 

Crystallization. The rearrangement of the 
molecules of metal into a crystalline form 
under continued shocks. This is often the 



cause of the breaking of the axles and jprings 
of a motor car. 

Cup, Priming: A small cup-shaped device 
provided with a cock, by which a small 
quantity of gasoline can be introduced into 
the cylinder of a gasoline engine. 

Current: The rate of flow of electricity; the 
quantity of electricity which passes per 
second through a conductor or circuit. 

Current Breaker: See "Contact Breaker". 
Current Indicator: A device to indicate 

the direction of current flow in a circuit; a 

polarity indicator. 

Current Rectifier: A device for converting 
alternating current into direct current. See 
"Converter". 

Cushion Tire: See "Tire, Cushion". 

Cut-Off, Gas Engine: That point in the 
cycle of an internal-combustion engine at 
which the admission of the mixture is dis- 
continued by the closing of the admission 
valve. 

Cut-Off, Steam Engine: That point in the 
cyle of a steam engine, or that point on an 
indicator diagram, at which the admission 
of steam is discontinued by the closing of the 
admission valve. 

Cut-Out, Automatic: A device in a bat- 
tery charging circuit designed to disconnect 
the battery from the circuit when the cur- 
rent is not of the proper voltage. 

Cut-Out, Muffler: A device by which the 
engine is made to exhaust into the % air 
instead of into the muffler. 

Cut-Out Pedal: Pedal by means of which 
the engine is made to exhaust into the air 
instead of into the muffler. 

Cycle: A complete series of operations 
beginning with the drawing in of the work- 
ing gas, and ending after the discharge of 
the spent gas. 

Cycle, Beau de Rochas: See "Beau de 
Rochas Cycle". 

Cylinder: A part of a reciprocating engine 
consisting of a cylindrical chamber in which 
a gas is allowed to expand and move a 
piston connected to a crank. 

Cylinder Bore: See "Bore". 

Cylinder Cock: A small cock used to allow 
the condensed water to be drained away 
from the cylinder of a steam engine, usually 
called a drain cock. 

Cylinder Head: That portion of a cylinder 
which closes one end. 

Cylinder Jacket: See "Jacket, Water". 

Cylinder Oil: Lubricant particularly adapt- 
ed to the lubrication of cylinder walls and 
pistons of engines. 

D 

Dash : The upright partition of a car in front 
of the front seat and just behind the bonnet. 

Dash Adjustment: Connections by which 
a motor auxiliary may be adjusted by a 
handle on the dash. Usually applied to 
carbureter adjustments. 

Dash Coil: An induction coil for jump- 
spark ignition, having an element for each 
cylinder, with dash connections to the com- 
mutator on the engine or camshaft. 

Dash Gage: A steam, water, oil, or electrio 
gage placed upon the dash of the car. 



407 



Digitized by 



Google 



10 



GLOSSARY 



Day Type of Engine: The two-cycle inter- 
nal-combustion engine with an air-tight 
crankcase. 

Dead Axle: See "Axle, Dead". 

Dead Center: The position of the crank and 
connecting rod in which they are in the same 
straight line. There are two positions, and 
in these positions no rotation of the crank- 
shaft is caused by pressure on the piston. 

Decarbonizer: See "Carbon Remover". 

Deflate: Reduction of pressure of air in a 
pneumatic tire. 

Deflector: In a two-cycle engine, the curved 
plate on the piston head designed to cause 
the incoming charge to force out the exhaust 
gases and thus assist in scavenging. 

Deflocculated Graphite: Graphite so finely 
divided that it remains in suspension in a 
liquid. 

Demountable Rimr A rim upon which a 
spare tire may be mounted ana carried, and 
so arranged that it may be easily and quickly 
taken off or put on the wheel. 

Denatured Alcohol: See "Alcohol, De- 
natured". 

Densimeter: See "Hydrometer". 

Depolarizer: Material surrounding the nega- 
tive element of a primary cell to absorb the 
gas which would otherwise cause polarising. 

Detachable Body: A body which may be 
detached from and placed upon the chassis. 

Detachable Rim: See "Demountable Rim". 

Diagram Indicator: See "Indicator Card". 

Diagram, Jeantaud: A diagrammatic rep- 
resentation of the running gear of an auto- 
mobile, showing it turning corners of various 
radii for the purpose of determining the 
front-axle and steering connections. 

Diesel Gas Engine: Four-cycle internal- 
combustion engine in which the explosion of 
the charge is accomplished entirely by the 
temperature produced by the high com- 
pression of the mixture. 

Differential, Bevel-Gear: A balance gear in 
which the equalizing action is obtained by 
means of bevel gears. 

Differential, Spur-Gear: A differential gear 
in which the equalizing action is obtained by 
spur gears. 

Differential Brake: See "Brake, Differen- 
tial". 

Differential Case: See "Differential Hous- 
ing". 

Differential Gear: A mechanism to permit 
driving the wheels and yet allow them to 
turn a corner without slipping. An arrange- 
ment such that the driving wheels may turn 
independently of each other v>n a divided 
axle, both wheels being under the control 
of the driving mechanism. Sometimes 
called balance, compensating, or equalizing 
gear. 

Differential Housing: The case that en- 
closes the differential gear. 

Differential Lock: A device which prevents 
the operation of the differential gear, so that 
the wheels turn as if they were on a solid 
shaft. 

Dimmer: An arrangement for lowering the 
intensity of, or reducing the glare from 
headlights. 

Direct Current: A current which does not 
change its direction of flow, as the current 



from a bavtery or a direct-current generator. 
Distinguished from an alternating current, 
which reverses its direction many times a 
minute. 

Direct Drive: Transmission of power from 
engine to the final driving mechanism at 
crankshaft speed. 

Discharge: In a storage battery, the passage 
of a current of electricity stored therein. In 
the ignition circuit, the flow of high-tension 
current at the spark gap. 

Disk Clutch: A clutch in which the power 
is transmitted by a number of thin plates 
pressed face to face. 

Distance Rod: See "Radius Rod". 

Distribution Shaft: See "Camshaft". 

Distributor: That part of the ignition sys- 
tem which directs the high-tension current, 
to the respective spark plugs in the proper 
firing order. 

Double Ignition: A method of ignition 
which comprises two separate systems, 
either of which may be used independently 
of the other, or both together as desired. 
Usually distinguished by two current 
sources and two sets of plugs. 

Drag: That action of a clutch or brake 
which does not completely release. 

Drag Link: That rod in a steering gear 
which forms the connection between the 
mechanism mounted on the frame and the 
axle stub, and transmits the movements of 
steering from steering post to wheels. 

Drive Shaft: The shaft transmitting the 
motion from the change gears to the driving 
axle; the torsion rod. 

Driving Axle: The axle of a motor car 
through which the power is transmitted to 
the wheels. 

Driving Wheel: The wheel to which or by 

which the motion is transmitted. 
Dry Battery: A battery of one or more dry 

cells. 

Dry Cell: A primary voltaic cell in which a 
moist material is used in place of the ordi- 
nary fluid electrolyte. 

Dual Ignition: An ignition system compris- 
ing two sources of current and one set of 
spark plugs. 

Dust Cap: A metal cap to be screwed over 
a tire valve to protect the latter from dust 
and water. 

Dynamo: The name frequently applied to a 
dynamo-electric machine used as a gener- 
ator. Strictly, the term dynamo should be 
applied to both motor and generator. 

Dynamometer: The form of equalizing gear 
attached to a source of power or a piece of 
machinery to ascertain the power necessary 
to operate the machinery at a given rate of 
speed and under a given load. 

E 

Earth: See "Ground". 

Economizer, Gas: An appliance to be 
attached to a float-feed carbureter to im- 
prove the mixture by automatically govern- 
ing the amount of air in the float chamber. 

Eccentric: A disk mounted off-center on a 
shaft to convert rotary into reciprocating 
motion. 

Economy, Fuel: The fuel economy of a 
motor is the relation between the heat units 



408 



Digitized by 



Google 



GLOSSARY 



11 



in -he fuel used in the motor and the woik 
or energy given out by the motor. 

Efficiency: The proportion of power ob- 
tained from a mechanism as compared with 
that put into it. 

Efficiency of a Motor: The efficiency of a 
gasoline motor is the relation between the 
heat units consumed by the motor and the 
work of energy in foot-pounds given out by 
it. Electrical efficiency of a motor is the 
relation between the electrical energy put 
into the motor and the mechanical energy 
given out by it. 

Ejector: An apparatus by which a jet of 
steam propels a stream of water in almost 
the same way as an injector, except that the 
ejector delivers it into a vessel having but 
little pressure in it. 

Electric Generator: A dynamo-electric ma- 
chine in which mechanical energy is trans- 
formed into electrical energy; usually called 
dynamo. 

Electric Horn: An automobile horn elec- 
trically operated. 

Electric Motor: A dynamo-electric machine 
in which electrical energy is transformed into 
mechanical energy. 

Electric Vehicle: An automobile propelled 
by an electric motor, for which current is 
supplied by a storage battery carried in the 
vehicle. 

Electrolyte: A compound which can be 
decomposed by electric current. In refer- 
ring to storage batteries, the term electro- 
lyte means the solution of sulphuric acid in 
water in which the positive and negative 
plates are immersed. 

Electromagnet: A temporary magnet which 
obtains its magnetic properties by the action 
of an electric current around it and which 
is a magnet only as long as such current is 
flowing. 

Electromotive Force: A tendency to cause a 
current of electricity to flow; usually syn- 
onymous with potential, difference of poten- 
tial, voltage, etc. 

Element: The dissimilar substances in a 
battery between which an electromotive 
force is set up, as the plates of a storage 
battery. 

Emergency Brake: A brake to be applied 
when a quick stop is necessary; usually 
operated by a pedal or lever. 

£n Bloc: That metrod of casting the cylin- 
ders of a gasoline engine in which all the 
cylinders are made as a single casting. 
Block casting; monoblock casting. 

End Flay; Motion of a shaft along its axis. 

Engine, Alcohol: An internal-combustion 
eugine in which a mixture of alcohol and air 
is used as fuel. 

Engine, Gasoline: An internal-combustion 
motor in which a mixture of gasoline and air 
is used as fuel. 

Engine, Kerosene: An internal-corn cusuor 
engine in which a mixture of kerosene ana 
air is used as fuel. 

Engine, Steam: &r ^ngrne in which the 
energy in steam is uoec to do work by 
moving the piston in a cylinder. 

Engine Primer: A small pump to force fuel 
into the carbureter. 

Engine Starter: An apparatus by which a 
gasoline engine may be started in its cycle of 
operations without use of the starting crank. 



It belongs usually to one of four classes; (1) 
Mechanical or spring actuated, such as a 
coil spring wound up by the running of the 
engine or a strap around the flywheel; (2) 
fluid pressure, ( such as compressed air or 
exhaust gases induced into the cylinder to 
drive the piston through one cycle; (3) the 
electric system, in which a small motor is 
used to turn the engine over; (4) combina- 
tions of these. 

Epicyclic Gear: See "Planetary Gear". 

Equalizing Gear: See "Differential Gear". 

Exhaust: The gases emitted from a cylinder 
after they have expanded and given up their 
energy to the piston; the emission of the 
exhaust gases. 

Exhaust, Auxiliary: See "Auxiliary Ex- 
haust". 

Exhaust Horn: An automobile horn in 
which the sound is produced by the e^aaust 
gases. 

Exhaust Lap: The extension of the inside 
edges of a slide valve to give earlier closing 
of the exhaust. Also called inside lap. 

Exhaust Manifold : A large pipe into which the 
exhaust passages from ail t^a cylinders open. 

Exhaust Port: The opening through which 
the exhaust gases are permitted to escape 
from the cylinder. 

Exhaust Steam: Steam which has given up 
its energy in the cylinder and is allowed to 
escape. 

Exhaust Stroke: The stroke of an internal- 
combustion motor during which the burned 
gases are expelled from the cylinder. 

Exhaust Valve: A valve in the cylinder of 
an engine through which the exhaust gases 
are expelled. 

Expanding Clutch: A clutch in which a 
split pulley is expanded to press on the inner 
circumference of a ring which surrounds it, 
and thus transmits motion to the ring. 

Expansion, Gas Engine: # That part of the 
cycle of > a gas engine immediately after 
ignition, in which the gas expands and drives 
the piston forward. 

Expansion, Steam Engine: That portion 
of the stroke of the steau- engine in which 
the steam is cut off by tne valves and con- 
tinues to perform work on the piston, increas- 
ing in volume and decreasing in pressure. 

Explosive Motor : See ' ' Internal-Combustion 
Motor". 

F 

Fan, Cooling: A mechanically operated fan 
for producing a current of air for cooling tne 
radiator or cylinder of a gas engine. 

Fan, Radiator: A mechanically operated 
rotary fan Used to induce the flow of air 
through the radiator to facilitate the cooling 
of the water. 

Fan Belt: The belt which drives the cooling 
fan. 

*an Pulley: A pulley permanently attached 
to the fan and over which the fan belt runs 
to drive it. 

Fat Spark: A short, thick, ignition spark. 
Feed Pump: A pump by which water is 

delivered from the tank to the boiler of a 

steam car. 
Feed Regulator: A device to maintain a 

uniform water level in a steam boiler by 

controlling the speed of the feed pump. 



409 



Digitized by 



Google 



12 



GLOSSARY 



Feed-Water Heater: An apparatus for 
heating the boiler-feed water, either by 
means of a jet of steam or steam-heated 
coils. 

Fender: A mud guard or shield over the 
wheels of a car. 

Field, Magnetic: Space in the neighborhood 
of the poles of a magnet in which the mag- 
netism exerts influence. Field also refers to 
the coils which produce the magnetism in an 
electromagnet. 

Fierce Clutch: A clutch which cannot be 
engaged easily. A grabbing clutch. 

Filler Board: Woodwork shaped to fill the 
space between the lower edge of the wind- 
snield and the dash. 

Fin: Projections cast on the cylinders of a 
gas engine to assist in cooling. 

Final Drive: That part of a car by which the 
driving effort is transmitted from the parts 
of the transmission carried on the frame to 
the transmission parts on the rear axle. 
The propeller shaft in a shaft-drive car. 

Fire Test: A test of a lubricant to determine 
the temperature at which it will burn. 

Firing: (1) Ignition of the charge in a gas 
engine. (2) The act of furnishing fuel 
under the boiler of a steam engine. 

First Speed: That combination of transmis- 
sion gears which gives the lowest gear ration 
forward. Slow speed; low speed. 

Flash Boiler: A boiler arranged to generate 
highly superheated steam almost instan- 
taneously, by allowing water to come in 
contact with very hot metal surfaces. 

Flash Generator: See "Flash Boiler". 

Flash Point: The temperature at which an 
oil will give off a vapor that will ignite when 
a flame comes in contact with it. 

Flash Test: A test to determine the flash 
point of oils. 

Flexibility: In an engine the ability to do 
useful work through a range of speeds. 

Flexible Coupling: See "Universal Joint". 

Flexible Shaft: A pliant shaft which will 
transmit considerable power when revolving. 

Flexible Tubing : A tube for the conduction 
of liquids or gases, which may be bent at a 
small radius without leaking. 

Float Carbureter: A carbureter for gasoline 
engines in which a float of cork or hollow 
metal controls the height of the liquid in the 
atomizing nozzle. Sometimes called float- 
feed carbureter. 

Float Valve: An automatic valve by which 
the admission of a liquid into a tank is con- 
trolled through a lever attached to a hollow 
sphere which floats on the surface of the 
liquid and opens or closes the valve accord- 
ing as it is high or low. 

Floating Axle: See "Axle, Floating". 

Floating the Battery on the Line: Charg- 
ing the battery while it is giving out current. 

Flooding: Excessive escape of fuel in a 
carbureter from the spraying nozzle. 

Flushing Pin: In a float-feed carbureter, a 
pin arranged to depress the float in priming. 
Also called primer and tickler. 

Flywheel: A wheel upon the shaft of an 
engine which, by virtue of its moving mass, 
stores up the energy of the gas transmitted 
to the flywheel during the impulse stroke 
and delivers it during the rest of the cycle, 
thus producing a fairly constant torque. 



Flywheel Marking: Marks on the face of a 
flywheel to indicate the time of valve open- 
ing and closing and thus assist in valve 
setting. 

Foaming: See "Priming". 

Fore Carriage: A self-propelled vehicle io 
which the motor is carried on the forward 
trucks, and propelling and steering is done 
with the forward trucks. 

Fore-Door Body: An automobile body hav- 
ing doors in the forward compartment. 

Four-Cycle or Four-Stroke Cycle: The 
cycle of operations in gas engines occupying 
two complete revolutions or four strokes. 

Four- Wheel Drive: Transmission of driving 
effort to all four wheels. 

Fourth Speed: That combination of trans- 
mission gears which gives the fourth from 
the lowest gear ratio forward. Usually the 
highest speed. 

Frame: The main structural part of a chas- 
sis. ^ It is carried upon the axles by the 
springs and carries the different elements of 
the car. 

Frame Hangers: See "Body Hangers". 
Free Wheel: A wheel so arranged that it 

can rotate more rapidly than the mechanism 

which drives it. 

Friction^ The resistance existing between 

two bodies in contact which tends to prevent 

their motion on each other. 
Friction Clutch: A device for coupling and 

disengaging two pieces of shafting while in 

motion, by the friction of cones or plates on 

one another. 
Friction Disk: The thin plate used in a disk 

or friction clutch. See Disk Clutch". 
Friction Drive: A method of transmitting 

power or motion by frictional contact. 

Fuel: A combustible substance by whose 
combustion power is produced. Gasoline 
and kerosene are the chief automobile fuels. 

Fuel Economy. See "Economy, Fuel". 

Fuel Feed, Gravity: See "Gravity Fuel 
Feed". 

Fuel Feed, Pressure: See "Lubrication, 
Force-Feed." 

Fuel Feed, Vacuum. See "Vacuum Fuel 

Feed". 

Fuel-Feed Regulator: A device in the fuel 
system of steam motor by which the rate of 
flow of fuel to the burner is automatically 
regulated. 

Fuel Level : The heigh l . of the top of the fuel 
in the float chamber of a carbureter. 

Fuel-Level Indicator: An instrument either 
permanently connected to the fuel tank or 
which may be inserted thereon to indicate 
the quantity of fuel in the tank. 

Fuel Tank, Auxiliary: A tank designed to 
hold a supply of fuel in addition to that 
carried in the main shaft. 

Fuse: A length of wire in an electric circuit 
designed to melt and open the circuit when 
excess current flows through it and thus pre- 
vent damage to other portions of the circuit. 

Fusible Plug: A hollow plug filled with an 
alloy which melts at a point slightly above 
the temperature of the steam in a boiler, as 
when the water runs low, thus putting out 
the fire and preventing the burning out oi 
the boiler. 



410 



Digitized by 



Google 



GLOSSARY 



13 



Gage: (1) Strictly speaking, a measure of, or 
instrument for determining dimensions or 
capacity. Practically, the term refers to an 
instrument for indicating the pressure or 
level of liquids, etc. (2) The distance be- 
tween the forward or rear wheels measured 
at the points of contact of the tires on the 
road. Tread; track. 

Gage Cock: A small cock by which a pipe 

leading to a gage may be opened or closed. 
Gage Lamp: Lamp, usually electric, placed 

above or near the gages to enable them to be 

read at night. 
Gage, Oil: See "Oil Gage". 
Gage, Tire: See "Tire-Pressure Gage". 
Gap: In automobiles, the spark gap. 
Garage: A building for storing and caring 

for automobiles. 
Garage, Portable: A garage which may be 

moved from one place to another either as a 

whole or in sections. 
Gas: Matter in a fluid form which is elastic 

and has a tendency to expand indefinitely 

with reduction in pressure. 
Gas Economizer: See "Economizer". 
Gas Engine: An internal-combustion motor 

in which a mixture of gas and air is used as 

fuel. The term is also applied to the gaso- 

'ine engine. 
Gas Engine, Otto: A four-stroke cycle 

engine developed by Otto and using the 

hot-tube method of ignition. 
Gas Generator: An apparatus in which a 

gas is generated for any use. 
Gas Lamp: See "Acetylene Lamp". 
Gases, Boyle's Law of:' See "Boyle's Law 

Of (-»■""»" 



Gases, Gay Lussac*s Law of: Called 
Charles' 8 Law and the Second Law of Oases. 
Law denning the physical properties of 

fases at constantly maintained pressure, 
t states that at constant pressure the vol- 
ume of gas varies with the temperature, the 
increase bei^g in proportion to the change of 
temperature and volume of the gas. 

Gasket: A thin sheet of packing material or 
metal used in making joints, piping, etc. 

Gasoline: A highly volatile fluid petroleum 
distillate; a mixture of fluid hydrocarbons. 

Gasoline-Electric Transmission: A sys- 
tem of propulsion in which a gasoline engine 
drives an electric generator, and the power 
is transmitted electrically to motors which 
drive the wheels. 

Gasoline Engine: An internal-combustion 
motor in which a mixture of gasoline and air 
is used as a fuel. 

Gasoline Primer: The valve on the car- 
bureter of a gasoline engine by which the 
action of the engine can be started. 

Gasoline-Tank Gage : A fuel-lever indicator 
for gasoline. 

Gasoline Tester: A hydrometer graduated 
to indicate the specific gravity of gasoline, 
usually in degrees Baume. 

Gate: A plate which guides the gearshift 
lever in making speed changes. 

Gather: Convergence of the forward por- 
tions of the front wheels. Toeing in. 

Gay Lussac'8 Law of Gases: See "Gases, 
Gay Lussac's Law of". 



Gear, Balance: See "Differential Gear". 

Gear, Bevel: See "Bevel Gear". 

Gear, Change-Speed: An arrangement or 
gear wheels which transmits the power of 
the motor to the differential gear at variable 
speeds independently of the motor speed. 

Gear, Differential: See "Differential". 

Gear, Fiber: A gear cut from a vulcanized 
fiber blank. 

Gear, Helical: A gear whose teeth are not 
parallel to the axis of the cylinders. 

Gear, Internal: A gear whose teeth project 
inward toward the center from the circum- 
ference of gear wheel. 

Gear, Planetary: See "Planetary Gears". 

Gear, Progressive : See "Progressive Change- 
Speed Gears". 

Gear, Rawhide: A gear cut from a blank 
made up of compressed rawhide. 

Gear, Selective: See "Selective Change- 
Speed Gears". 

Gear, Timing: See "Timing Gears". 

Gear, Worm: A helical gear designed for 
transmitting motion at angles, usually at 
right angles and with a comparatively great 
speed reduction. 

Gearbox : The case covering the change-speed 
gears. 

Gear Shifting: Varying the speed ration 
between motor and rear wheels by operating 
the change-speed gears. 

Gear-Shift Lever: A lever by which the 
change-speed gears are shifted. 

Geared -Up Speed: A speed obtained by an 
arrangement of gears in the gearset such that 
the propeller shaft rotates more rapidly than 
the crankshaft. 

Gearset: See "Gear, Change-Speed". 

Generator, Acetylene: See "Acetylene Gen- 
erator". 

Generator, Electric: See "Electric Gener- 
ator". 

Generator, Steam: A steam boiler. 

Generator Tubing: Tubing by which acety- 
lene is conducted from the generator to the 
lamp. 

Gimbal Joint: A form of universal joint. 

Gong: A loud, clear sounding bell, usually 
operated either electrically or by foot power. 

Governor: A device for automatically regu- 
lating the speed of an engine. 

Governor, Dynamo: A method of auto- 
matic control of the generator (usually an 
ignition generator, in automobile work) by 
which its speed is maintained approximately 
constant. 

Governor, Hydraulic: A governor applied 
to engines cooled by a pump circulation of 
water in such a way that the throttle opening 
is controlled by the pressure of the water. 

Governor, Spark: A method of automati- 
cally controlling the speed of the engine by 
varying the time of ignition. See "Gov- 
ernor". 

Grabbing Clutch: See "Fierce Clutch". 

Gradometer: An instrument for indicating 
the degree of the gradient or the per cent of 
the grade. It consists of a level with a 
graduated scale. 

Graphite: One of the forms in which carbon 
occurs in matter. Also known as black lead 



411 



Digitized by 



Google 



14 



GLOSSARY 



and plumbago. Used as a lubricant in pow- 
dered or flake form in the cylinders of 
explosive engines. 

Gravity-Feed Oiling System: See "Lubri- 
cation, Gravity". 

Gravity Fuel Feed: Supply of fuel to the 
carbureter from the tank by force of gravity. 

Grease and Oil Gun: A syringe by means 
of which grease or oil may be introduced 
into the bearings of the machinery. 

Grease Cup: A device designed to feed 
grease to a bearing by the compression of a 
Hand screw. 

Grid: A lead plate formed in the shape of a 
gridiron to sustain and act as a conductor of 
electricity for the active material in a 
storage battery. 

Grinding Valves: See "Valve Grinding". 

Gripping Clutch: See "Fierce Clutch". 

Ground: An electric connection with the 
earth, or to the framework of a machine. 

H 

Half-Motion Shaft : See "Half-Time Shaft". 

Half -Time Gear: See "Timing Gears'*. 

Half -Time Shaft: The cam shaft of a four- 
cycle gas engine. It revolves at one-half 
the speed of the crankshaft. 

Hammer Break: A make-and-break ignition 
system in which the spark is produced when 
the moving terminal strikes the stationary 
terminal like a hammer. 

Header: A pipe from which two or more 
pipes branch. Manifold. 

Heater, Automobile: A device for warming 
the interior of an automobile, usually electric, 
or by means of exhaust gases or jacket 
water. 

High Gear: That combination of change- 
speed gears which gives the highest speed. 

High-Tension Current: A current of high 
voltage, as the current induced in the second- 
ary circuit of a spark coil. 

High-Tension Ignition: Ignition by means 
of high-tension current. 

High-Tension Magneto: A magneto which 
delivers high-tension current. 

Honeycomb Radiator: A radiator consist- 
ing of many very thin tubes, giving it a 
cellular appearance. 

Hood: (1) That part of the automobile 
body which covers the frame in front of the 
dash. The engine is usually under the hood. 
(2) The removable covering for the motor. 

Hooke's Coupler: See "Universal Joint". 

Horizontal Motor: A motor the center line 
of whose cylinder lies in a horizontal plane. 

Horn, Automobile: A whistle or horn for 
giving warning of the approach of the 
automobile. 

Horsepower: The rate of work or energy 
expended in a given time by a motor. One 
horsepower is the rate or energy expended 
in raising a weight of 1>60 pounds one foot 
in one second, or raiding 33,000 pounds one 
foot in one minute. 

Horsepower Brake: The oower delivered at 
the flywheel of an internal combustion 
engine as ascertained by a brake iesk 

Horsepower, Rated: The calculated power 
which may be expected to be delivered by a 
motor* In America the term usually refers 



«\ S 6 * horsepower as calculated by the 
S.AJL formula. 

Hot- Air Intake: The pipe or opening con- 
veying haated air to the carbureter. 

Hot-Head Ignition: The method of igniting 
the charse in a gas-engine cylinder by main- 
taining the head of the combustion chamber 
at a high temperature from the internal heat 
of combustion, as in the Diese*. engine. 

Hot-Tube Ignition. An ignition device 
formerly used for gab engines in which a 
closed metal *ube *a heated red-hot ly a 
Bunsen flame. When the compressed gases 
in the cylinder are allowed to come in con- 
tact with this, ignition takes place. 

Housing: A metallic covering for moving 
parts. 

H.P.: (1) Abbreviation for horsepower. (2) 

Abbreviation for high pressure. 
Hub Cap: A metal cap placed over the outer 

end of a wheel hub. 
Hydrocarbons: Chemical combinations of 

carbon and hydroger in varied proportions, 

usually distillates »f petroleum, su«h a* 

gasoline, kerosene, 3tc. 
Hydrometer: An instrument by which the 

specific gravity or density of liquids may l*$ 

ascertained. 
Hydrometer Scale, Baume's: An arbitrary 

measure of specitc gravity. 



I-Beam: Sometimes called I -Section. A struc- 
tural piece having a cross section resemoling 
the letter I. I-Beam front axle. 

Igniter: An insulated contact plug without 
sparking points, used in make-and-break 
ignition with low-tension magneto. 

Igniter, High-Speed: An igniter having a 
short spark coil for high-speed engines. 

Igniter, Juirp-Spark: A system of ignition 
in which -ji used a current of high piessurc, 
which will jump across a gap in tie high- 
pressure circuit, causing a spark at the gap. 

Igniter, Lead of: Amount by which the igni- 
tion is advanced. See "Advanced Ignition". 

Igniter, Primary: The apparatus in a pri- 
mary circuit for mulcing and breaking the 
circuit. 

Igniter Spring: A spring to quickly break 
the circuit of a primary igniter. 

Ignition, Advancing: See "Advanced Ig- 
nition". 

Ignftion, Battery: A system which gets its 
supply of current from a storage battery or 
dry cells. This system usually consists of a 
battery, a step-up coil, and a distributor for 
sending the current to the different spark 
plugs. 

Ignition, Catalytic: Method of ignition for 
explosive motors based on the property of 
some metals, particularly spongy platinum, 
of becoming incandescent when in contact 
with coal gas or carbonised air. 

Ignition, Double: See "Double Ignition". 

Ignition, Dual: See "Dual Ignition". 

Ignition, Fixed: Ignition in which the 
spark occurs at a given point in the cycle 
and cannot be changed from that point ut 
the will of the operator except bv ^timiiur 
the Ignition system. Fixed »oark. 

Ignition, Generator ? Ignition current which 
is furnished bv a combination lighting 
generator and magneto. The generator in 



412 



Digitized by 



Google 



GLOSSARY 



16 



fitted with an interrupter and distributor. 
Sometimes refers to system in which a gener- 
ator charges a battery and the latter fur- 
nishes the ignition current in connection 
with a coil and distributor. 

Ignition, High-Tension: Sometimes called 
jump-spark. Ignition which is effected by 
means of a high-tension or high-voltage 
current which is necessary to jump a gap in 
the spark plug. 

Ignition, Hot-Head: See "Hot-Head Igni- 
tion". 

Ignition, Jump-Spark: See "Ignition, 
High-Tension". 

Ignition, Low-Tension: See "Ignition, 
Make-and-Break' ' . 

Ignition, Make-and-Break: A system in 
which the spark is produced by the breaking 
or interruption of a circuit, the break 
occurring m the combustion space of the 
cylinder. The current used is of low-volt- 
age, hence "die synonym, low-tension ignition. 

Ignition, Magneto: Ignition produced by 
an eiectric generator, called a magneto, which 
is or/erated by the gas engine for which it 
furnishes current. Dynamo ignition. Gen- 
erator ignition. 

Igsi cum, Matter Vibrator : A system which 
usee as m^iiy non-vibrator coils as 'there 
are cylinders, ard one additional coil, called 
the mastcf vibrator, for interrupting the 
primary circuit for all coils. The master 
vibrator also is used with vibrator coils in 
wWh the vibrators are short-circuited. 

Ignition, Premature: Ignition occurring so 
*ar before the top dead center mark that the 
explosion occurs Delve the piston has reached 
upper dead center. 

Ignition, Primary: An ignition system in 
which a low-tension current flows through a 
primary coil, the circuit being mechanically 
opened, allowing a high-tension spark to 
jump across the gap. See "Primary Coil". 

'ignition, Retarding: Setting the spark of 
an internal-combustior motor so that the 
ignition will occur at a later part of the 
stroke. 

Ignition, Self: ^xploson of the combusti- 
ble charge by heat other than that produced 
by the spark. Incandescent carbon will 
cause this. Mjtor overheating because of 
lack of water is another cause. 

Ignition, Single: A system using but one 
source of current. 

Ignition, Synchronized: Ign.tion by means 
of which the timing in each cylinder of a 
multicylinder engine is the same. In syn- 
chronized ignition the spark occurs at the 
same point in the cycle in each cylinder. 
This type of ignition is obtained with a 
magneto and is lacking in a multi-coil sys- 
tem using vibrator coils. 

Ignition, Timing of: The adjustment of the 
ignition system so that ignition will take 
place at the desired part of the cycle. 

Ignition, Two-Independent: See "Igni- 
tion, Double". 

Ignition, Two-Point: A system comprising 
two ignition sources, or a double-distributor 
magneto, and two sets of spark plugs, both 
ot whicL spark at the same time. 
Ignition Distributor: See "Distributor." * 
Ignition Switch: A control or switch for 
turning the ignition current on and off volun- 
tarily 



I. H. P.: Abbreviation for indicated horse' 
power. 

Indicated Horsepower: (1) The horse- 
power developed Dy the fuel on the pistons, 
in contradistinction to brake horsepower. 
See "Horsepower, Brake". (2) The horse- 
power of an engine as ascertained from an 
indicator diagram. 

Indicator: An instrument by which the 
working gas in an engine records its working 
pressure. 

Indicator Card: A figure drawn by means 
of an indicator by the working gas in an 
engine. Also called indicator diagrpm. 

Induction Stroke: The downstroke of a 

Siston which causes a charge of mixture to 
e drawn into the cylinder. 

Inflammation: The act or period of com- 
bustion of the mixture in the cylinder. 

Inflate: To increase the pressure within a 
tire by forcing air into it. 

Inflator, Mechanical Tire: A small power- 
driven air-pump for inflating the tire; either 
driven by gearing, chain, or belt from the 
engine shaft, or by friction from the flywheel. 

Inherent Regulation: Expression applied 
to elec*ric generators which use no outside 
means of regulating the output, the regula- 
tion being affected by various windings of 
the armature and fields. 

Initial Air Inlet: See "Primary Air Inlet". 

Initial Pressure: Pressure in a cylinder 
after the charge has been drawn in but not 
compressed. 

Injector: A boiler-feeding device in which 
the momentum of a steam jet, directed by a 
series of conical nozzles, carries a streani of 
water into the boiler, the steam condensing 
within and heating the water which it forces 
along. 

Inlet, Valve: The valve which controls the 
inlet port and so allows or prevents mixture 
from passing to the cylinder. 

Inlet Port: Passage or entrance in the cylin- 
der wall through which the fuel mixture is 
taken. Sometimes called intake port. 

Inlet Manifold: Sometimes called intake 
manifold or header. A branched pipe con- 
nected + o the mixing chamber at one end 
and at the br^ucl* ends to the cylinders so as 
to communicate with the inlet ports. 

Inlet Manifolc, Integral: A manifold or 
header cast integral with the cylinder. 

Inner-Tire Shoe: A piece of leather or 
rubber placed within the tire to protect the 
inner tube. 

Inner Tube: A soft air-tight tube of nearly 
pure rubber, which fits within a felloe upon 
the casing. 

Inside Lap: See "Exhaust Lap". 

Intake Manifold: The large pipe which 
supplies the 'smaller intake pipes from each 
cylinder of a gas engine. 

Intake Pipe: Sometimes made synonymous 
with inlet manifold. Correctly, the pipe 
from the carbureter to the inlet manifold. 

Intake Stroke: See "Induction Stroke". 

Intensifier: See "Outside Spark Gap". 

Intermediate Gear: A gear in a change- 
speed set between high and low. In a 
three-speed set it would be second speed. 
In a four, either second or third. 



413 



Digitized by 



Google 



16 



GLOSSARY 



Intermediate Shaft t See "Shaft, Inter- 
mediate". 

Internal-Combustion Motor: Any prime 
mover in which the energy is obtained by 
the combustion of the fuel within the 
cylinder. 

Internal Gear: See "Gear, Internal". 
Interrupter: See "Vibrator". 



Keyway: Slot in a rotating member used t» 
hold the key 

Kick Switch:* Ignition switch mounted so 
that the driver can operate it with the foot. 

Kilowatt: An electrical unit equal to 1000 
watts. 

Knuckle Joint: See "Swivel Joint". 



Jack: A mechanism by which a small force 
exerted over a comparatively large distance 
is enabled to raise a heavy body. Used for 
raising the automobile axle to remove the 
weight from the wheels. 

Jacket, Water: A portion of the cylinder 
casting through which water flows to cool 
the cylinder. 

Jacket Water: The cooling water circulating 
in a water-cooling system. 

Jackshaft: Shaft used in double-chain drive 
vehicles. Shaft placed transversally in the 
frame and driving from its ends chains which 
turn the rear wheels mounted on a dead 
axle. 

Jeantaud Diagram: See "Diagram, Jean- 
taud". 

Joint Knuckle: See "Swivel Joint." 

Joule's Law of Gases: See "Gases, Joule's 
Law of". 

Jump Spark: A spark produced by a sec- 
ondary jump-spark coil. 

Jump Spark, Circuit Maker: A mechani- 
cally operated switch by which the circuit in 
a jump-spark ignition system is opened and 
closed. ' 

Jump-Spark Coil: An electrical transformer 
and interrupter, consisting of a primary 
winding of a few turns o f coarse wire sur- 
rounding an iron core, and a secondary 
winding consisting of a great number of 
turns of very fine wire. The condenser is 
usually combined with this. Also known as 
secondary spark coil. 

Jump-Spark Igniter: See "Igniter, Jump- 
Spark". 

Jump-Spark Plug: See "Spark Plug". 

Junction Box: A portion of an electric- 
lighting system to which all wires are carried 
for the making of proper connections. 

Junk Ring: A packing ring used in sleeve- 
valve motors. It has the same functions as 
a piston ring. See "Piston Ring". 



Kerosene: A petroleum product having a 
specific gravity between 58° and 40° Baume\ 
It is used as a fuel in internal-combustion 
engines and can often be used in gasoline 
engines by starting the engine on gasoline, 
then switching to kerosene. 

Kerosene Burner: A burner especially 
adapted to use kerosene as a fuel. 

Kerosene Engine: An engine using kero- 
sene as fuel. 

Key: A semicircular or oblong piece of 
metal used to hold a member firmly on a 
revolving shaft so as to prevent the member 
from rotating. 

Key, Baldwin : A key with an oblong section. 

Key, Woodruff: A key with a semicircular 
section. » 



Labor: The jerky operation of an engine. 

The engine is said to labor when it cannot 

pull its load without misfiring or jerking. 
Lag, Combustion: The time between the 

instant of the spark occurrence and the 

explosion. 

Lag, Ignition: The time between the instant 
of spark occurrence and the time at which 
the spark mechanism producing it begins 
to act. 

Lamp, Trouble: Sometimes called inspec- 
tion lamp. A small electric bulb carried in 
a suitable housing, and attached to a long 
piece of lamp cord. Used for inspecting 
parts of the car. 

Lamp Bulb: The incandescent bulb used in 
a lamp. 

Lamp Bracket: A support for a lamp. 

Lamp Lighter: An apparatus for lighting 
gas lamps by electricity. The lamps are 
usually so arranged that by pushing the 
button the gas is turned on and the spark 
made at the same time. 

Landaulet: A type of car which may be 
used as an open or closed car. The rear por- 
ti.n of the body may be folded down like a 
top. 

Landaulet Body: An automobile body 
resembling a limousine body, but having a 
cover, fitted to the back, which may be let 
down, leaving the back open. The top 
generally extends over the driver. 

Lap: To make parts fit perfectly by operat- 
ing them with an abrasive, such as ground 
glass, between the rubbing surfaces. To 
finish. 

Lap of Steam Valves: In the slide valve of 
a steam engine, the amount by which the 
admission edges overlap the steam port when 

. the valve is central with the cylinder case. 

Layshaft: A countershaft or secondary shaft 
of a gearset operated by the main or shifter 
shaft. 

Lead, or Lead Wire: Any wire carrying 
electricity. 

Lead: In a steam engine the amount by 
which the steam port is opened when the 
piston is at the start of its stroke. 

Lead Battery: See "Accumulator". 

Lead of Igniter: See "Igniter, Lead of". 

Lead of Valve: In an engine the amount by 
which the admission port is opened when the 
piston is at the beginning of the stroke; 
according as this is greater or less, the admis- 
sion of working fluid is varied through 
sever"' fractions of the stroke. 

Lean Mixture: Fuel after leaving the car- 
bureter, which contains too much air in pro 
portion to the gasoline. Sometimes called 
thin mixture, rare mixture, or weak mixture. 

Lever, Brake: See "Brake Lever." 

Lever, Change-Speed: Lever by which the 
different combinations of change gears are 
made so as to vary the speed of the driving 



414 



Digitized by 



Google 



GLOSSARY 



17 



wheels in relation to the speed of the engine ; 
also called gearshift lever. 

Lever, Spark: Lever by which the speed and 
power of the engine are controlled by adjust- 
ing the time of ignition. 

Lever, Steering: See "Steering Lever". 

Lever, Throttle: A lever by which the speed 
and power of the engine are controlled by 
adjusting the amount of mixture admitted 
to the cylinder. 

Lever Lock: An arrangement for locking the 
gearshift lever in free position so that with 
the engine running the driving axle will not 
be driven. 

Lift: The distance through which a poppet 
valve is moved in opening from fully-closed 
to fully-open position. 

Lifting Jack: See "Jack". 

Lighting Outfit, Electric: An outfit for 
electrically lighting an automobile. This 
usually consists of a dynamo, storage bat- 
tery, and lamps and switchboard, with the 
necessary wiring and cut-outs. 

Limousine Body: An enclosed automobile 
body having the front and sides with side 
doors. The top extends over the seat of the 
driver. 

Liner: One or more pieces of metal placed 
between two parts so they may be adjusted 
by varying the thickness of the liner. Some- 
times called a shim. Also refers to a tool 
used for lining up parts. 

Liner, Laminated : A liner or shim made in 
a number of parts, the thickness being 
varied by removing or adding parts. 

Lines of Force: See "Field, Magnetic". 

Link Motion: In a steam engine, the name 
for the arrangement of eccentric rods, links, 
hangers, and rocking shafts by which the 
relative motion and position of the slide 
valves are changed at will, providing for 
varying rates of expansion of the steam and 
thus varying the speed for either forward or 
backward motion. 

Live Axle: See "Axle, Live". 

Lock, Auto Safety: A device arranged so 
that it is impossible to start the motor car 
except by the proper combination or key. 

Lock Nut: A nut placed on a bolt immedi- 
ately behind the main nut to keep the main 
nut from turning. 

Lock Switch: A switch in the ignition cir- 
cuit so arranged that it can not be thrown on 
except by the use of a key. 

Lock Valve: A valve capable of being secured 
with lock and key. 

Long-Stroke: A gas engine whose stroke is 
considerably greater than its bore. 

Lost Motion: Sometimes called play or 
backlash. Looseness of space between two 
moving parts. 

Louver: A slit or opening in the side of a 
hood or bonnet of a motor car. Used to 
allow air from the draft to escape. A venti- 
lator. 

Low Gear: The lowest speed gear. First 
speed in a change-speed set. 

Low-Speed Adjustment: A carbureter ad- 
justment which regulates the mixture when 
the motor is operating slowly, with little 
throttling opening. 

Low-Speed Band: The brake or friction 
band which controls the low speed of a plan- 
etary change-speed set. 



Low-Tension Current: A current of low 
voltage or pressure, such as is generated by 
dry cells, storage battery, or low-tension 
magneto. 

Low -Tension Ignition: See "Ignition, 
Make-and-Break". 

Low-Tension Magneto: A magneto which 
initially generates a current of low voltage. 

Low-Tension Winding: The winding of a 
transformer or induction coil through which 
the primary or low-tension current flows. 

Low Test: Gasoline which has a high den- 
sity, thus giving a low reading on the Baume* 
scale. Low-grade gasoline. 

Low-Water Alarm: An automatic arrange- 
ment by which notice is given that the 
water in the boiler is becoming too low for 
safety. 

Lubricant: An oil or grease used to dimin- 
ish friction in the working parts of machin- 
ery. 

Lubrication: To supply to moving parts 
and their bearings grease, oil, or other lubri- 
cant for the purpose of lessening friction. 

Lubrication, Circulating: A system in 
which the same oil is used over and over. 

Lubrication, Constant-Level: A system 
in which the level in the crankcase is kept to 
a predetermined level by means of a pump. 

Lubrication, Force-Feed: Method of lubri- 
cating the moving parts of an engine by 
forcing the oil to the points of application by 
means of a pump. 

Lubrication, Gravity: Method of supplying 
oil to moving parts of an engine by having a 
reservoir at a certain height above the highest 
point to be lubricated and allowing the oil 
to flow to the points of application by 
gravity. 

Lubrication, Non -Circulating: A system 
in which the same oil is used but once. 

Lubrication, Pressure-Feed: See "Lubri 
cation, Force-Feed". 

Lubrication, Sight-Feed: System of lubri- 
cation in which the oil pipe to different 
points of application is led through a glass 
tube in plain sight; usually at a point on the 
dashboard. 

Lubrication, Splash: Method of lubricat- 
ing an engine by feeding oil to the crank- 
case and allowing the lower edge of the 
connecting rod to splash into it. 

Lubricator: A device containing and supply- 
ing oil or grease in regular amounts to the 
working parts of the machine. 

Lubricator, Force-Feed: A pumj>-like de- 
vice which automatically forces oil to the 
moving parts. 

M 

Magnet: A piece of iron or steel which has 
the characteristic properties of being able to 
attract other pieces of iron and steel. 

Magnet, Horseshoe: A magnet shaped like 
the letter U. 

Magnet, Permanent: A magnet which 
when once charged retains its magnetism. 

Magnetic Field: See "Field, Magnetic". 

Magnetic Spark Plug: A spark plug used 
in a make-and-break system of ignition in 
which contact is obtained by means of a 
magnet. 

Magneto: See "Ignition, Magneto". 



415 



Digitized by 



Google 



18 



GLOSSARY 



Magneto: 

ator". 



See "Magneto-Electric Gener- 



Magneto, Double-Distributor: A magneto 
with two distributors feeding two sets of 
spark plugs, two in each cylinder and both 
sparking at once. See Ignition. Two- 
Point." 

Magneto, High-Tension : A magneto has 
' two armature windings and requires no out- 
side coil for the generation of high-tension 
current. 

Magneto, Induction: A type of magneto in 
which the armature and fields are stationary 
and a rotator or spool-shaped piece of metal 
is used to break the lines of force. 

Magneto, Low-Tension : See ' ' Low-Tension 
Magneto". 

Magneto, Rotating Armature: A magneto 
in which the armature winding revolves. 

Magneto Bracket: A shelf or portion of the 
crankcase web used to support the magneto. 

Magneto Coupling: A flexible joint which 
connects the magneto with a revolving 
motor shaft. 

Magneto Distributor: See "Distributor". 

Magneto-Electric Generator: A machine 
in which there are no field magnet coils, the 
magnetic field of the machine being due to 
the action of permanent steel magnets. 
Usually contracted to magneto. 

Main Bearing: A bearing used for support- 
ing the crankshaft. 

Manifold: A main pipe or chamber, into 
which or from which a number of smaller 

Ripes lead to other chambers. See "Intake 
lanifold", "Exhaust Manifold", and "Inlet 

Manifold". 
Manometer: A device for indicating either 

the velocity or the pressure of the water in 

the coiling system of a gasoline motor. 
Master Vibrator: A single vibrator which 

interrupts the current to each of a set of 

several spark coils in order. 
Mean Effective Pressure: The average 

pressure exerted upon a piston throughout 

its stroke. 

M.E. P.: Abbreviation for mean effective 
pressure. 

Mercury Arc Rectifier: A mercury vapor con- 
verter. See "Mercury Vapor Converter'^. 

Mercury Vapor Converter: An apparatus 
for converting alternating current into direct 
current by means of a bubble of mercury in 
a vacuum. The vapor of mercury possesses 
the property of allowing the flow of current 
in one direction only. Its principal use is 
for charging storage batteries. 

Mesh: Two gears whose teeth are so posi- 
tioned that one gear will drive the othei are 
said to be in mesh. 

Misfire: Failure of the mixture to ignite in 
the cylinder; usually due to poor ignition or 
poor mixtures. 

Miss: The failure of a gas engine to exp ode 
in one or more cylinders. Sometimes ct lied 
misfiring. 

Mixing Chamber: A pipe or chamber 
placed between the carbureter and inlet 
manifold. Sometimes integral with the car- 
bureter or manifold. 

Mixing Tube: A tubular carbureter for a 
gas or gasoline engine. 

Mixing Valve: A device through which air 
and gas are admitted to form an explosive 



mixture. The carbureter of a gasoline 
engine combines the mixing valve and 
vaporiser. 

Mixture: The fuel of a gas engine, consisting 
of sprayed gasoline mixed with air. 

Monobloc: Cast en bloc or in one piece. 
Refers usually to cylinders, which are cast 

. two or more at once. 

Motocycle: A trade name for a special make 
of motorcycle. • 

Motor, Electric: See "Electric Motor". 

Motor, Gasoline: See "Gasoline Motor". 

Motor, High-Speed: A gas engine whose 
rotative speed is very high and whose power 
output goes up with the speed to an unusual 
degree. 

Motor, Horizontal: A gas engine whose cyl- 
inder axis lies in a horizontal plane. 

Motor, I-head: A gas engine which has 
cylinders, a section of which resembles the 
letter I. This type has the valves in the 
head. 

Motor, L-Head: A gas engine in which a 
section of cylinders resembles the letter L. 
The valves in this type are all on one side. 

Motor, Long-Stroke: See "Long-Stroke 
Motor". 

Motor, Non-Poppet: A gas engine whose 
valves are not of the poppet type. In this 
class is the Knight sleeve valve, the rotary 
valve, and the piston valve. 

Motor, Overhead Valve: A motor with cyl- 
inders whose valves are in the head. 

Motor, Piston Valve: A gas engine using 
valves which are in the form of pistons. 

Motor, Poppet: A gas engine using poppet- 
type valves. See "Poppet Valve". 

Motor, Revolving Cylinder: A motor whose 
cylinders revolve as a unit. 

Motor, Rotary Valve: One in which the 
valves consist of slots cut out along cylin- 
drical rods which rotate in the cylinder 
casting. 

Motor, Sliding Sleeve: The Knight type 
motor in which thin sleeves slide up and 
down in the cylinder, the sleeves having 
ports which register with the inlet and 
exhaust manifolds. 

Motor, T-Head: A gas engine with the 
valves on opposite sides of the cylinders, a 
section of which resembles the letter T. 

Motor, V-Type: A motor whose cylinders 
are set on the crankcase so as to form an 
angle of 45 to 90 degrees between them. 

Motor, Vertical: A motor with the cylindei 
axis in a vertical plane. 

Motorcycle: A bicycle propelled by a gaso- 
line engine. 

Mud Guard: Metal or leather strips placed 
over the wheels to catch the flying mud and 
to prevent the clothing from coming in con- 
tact with the wheels when entering and 
leaving the car. 

Muffler Cut-Out: See "Cut-Out, Muffler". 

Muffler Cut-Out Pedal: See "Cut-Out 
Pedal". 

Muffler Exhaust: A vessel containing par- 
titions, usually perforated with small holes 
and designed to reduce the noise occasioned 
by the exhaust gases of an engine, by forcing 
the gases to expand gradually. 



416 



Digitized by 



Google 



GLOSSARY 



19 



Muffler Explosion: Explosion of unburned 
gases in exhaust passages of the muffler, 
usually due to poor ignition or poor mixture. 

Multiple Circuit: A compound circuit in 
which a number of separate sources or 
electrically operated devices, or both, have 
all their positive poles connected to a single 
positive conductor and all their negative 
poles to a single negative conductor. 

N 

i 

N.A.A.M.: Abbreviation for National Asso- 
ciation of Automobile Manufacturers. 

Naphtha: A product of the distillation of 
petroleum used to some extent for marine 
engines. 

Needle Valve: A valve in a carbureter used 
for regulating the amount of gasoline to flow 
in with the mixture. 

Negative Plate: Plate of a storage battery to 
which current returns from the outside 
circuit. 

Negative Pole: That pole of an electric 
source through which the current is assumed 
to enter or now back into the source after 
having passed through the circuit external 
to the source. 

Neutral Position: The position of the 
change-speed lever which so places the gear* 
that the motor may run idle, the car remain- 
ing still. 

Non-Defla table Tire: See "Tire, Non- 
Puncturable". 

Non-Freezing Solution: A solution placed 
into the radiator of a motor car to prevent 
the water therein from freezing. Alcohol 
and glycerine are the usual anti-freezing 
agents. See "Anti-Freezing Solution". 

Non-Puncturable Tire: See "Tire, Non- 
Puncturable". 

Non-Skid Device: See "Anti-Skid Device". 



Odometer: (1) The mileage-recording mech- 
anism of a speedometer. (2) An instrument 
to be attached to an automobile wheel to 
automatically indicate the distance traveled. 
Odometer, Hub: A speed-recording device 

which is placed on the hub cap of a wheel- 
Offset: Off center, as a crankshaft in which 
a line vertically through the crankpins does 
not coincide with a line vertically through 
the center of the cylinder. 
Ohm: (1) tJnit of electrical resistance. (2) 
Amount of electrical resistance. Sueb resist- 
ance as would limit the flow of electricity 
under an electromotive force of one volt to 
a current of one ampere. 
Ohm's Law: The law which gives the rela- 
tion between voltage, resistance, and current 
flow in any circuit. Expressed algebraically,' 

C— -r where C is the current flowing in ara- 

K 
peres, I the voltage and R the ohmic resist- 
ance. 

Oil Burner: A burner equipped with an 
atomizer for breaking up liquid fuel into a 
spray. ' 

Oil Engine: An internal-combustion motor 
using kerosene or other oil as fuel. 

Oil Gage: (1) A gage to indicate the flow 
of oil in the lubricating system. (2) Used 
to show the level of oil in a compartment in 
the base of a gas engine. 



Oil Gun: A cylinder with a long point ard a 
»pring plunger for iquirting oil or grease 
into inaccessible parts of a machine. 

Oil Pump: A small f orce pump providing a 
constant positive supply of oil under pres- 
sure; usually considered ' to be more reliable 
than a lubricator. 

Oiler: An automobile device , for oiling 
machinery. 

Opposed Motor: A gasoline engine whose 
cylinders are arranged in pairs on opposite 
sides of the crankshaft, both connecting 
rods of each pair being connected to the 
same crank, to that the shock of the explo- 
sion in one will be balanced by the cushion- 
ing effect of the compression in the other. 
In general these motors are two-cylinder, 
horizontal. 

Otto Cycle: See "Four-Stroke Cycle". 

Outside Spark Gap: See "Spark Gap, Out- 
side". 

Overcharged: The state of the storage bat- 
tery when it has been charged at too high a 
rate or for too great a length of time, 

Overhead Camshaft: A camshaft which is 
placed above the cylinder of a gas engine. 

Overhead Valves: See "Motor, Overhead 
Valve". 

Overheating: The act of allowing the motor 
to reach an excessively high temperature 
due to the heat of combustion being not 
carried away rapidly enough by the cooling 
devices, or to insufficient lubrication. Over- 
heating of a bearing is due to insufficient 
lubrication. 



Packing: The material introduced between 
the parts of couplings, joints, or valves, to 
prevent the leakage of gas or liquids to or 
from them. 

Panel, Charging: A small switchboard for 
charging a storage battery. 

Parallel Circuit: See "Multiple Circuit". 

Patch, Tire-Repair: Rubber strips for mak- 
ing repairs in punctured or ruptured tires. 

Petcock: A control cock which when open 
allows gas or liquid to escape from the cham- 
ber to which it is attached. 

Petrol: Word used in England for gasoline. 

Picric Acid: Acid which may be added to 
gasoline to increase the motor efficiency. 
Gasoline will absorb about five per cent of 
its weight of picric acid. 

Pin, Taper: A conically shaped pin. 

Pinch: A cut in an inner tube caused by the 
tube being caught or pinched between the 
outer casing and the rim. 

Pinion: (1) The smaller of any pair of 
gears. (2) A small gear made to run with 
a larger gear. 

Piston: The hollow, cylindrical portion 
attached to the connecting rod of a motor. 
The reciprocating part which takes the 
strain caused by the explosion. 

Piston Air Valve: A secondary air valve in 
the piston of earlier types of gas engines to 
compensate the imperfect operation of sur- 
face carbureters used with those engines 
and to secure the injection of a sufficient 
quantity of air to insure the combustion of 
the charge. 

Piston Head: The top of the piston. 



417 



Digitized by 



Google 



20 



GLOSSARY 



Piston Pin: A pin which holds the connect- 
ing rod to the piston. 

Piston Ring: (1) A metal ring inserted in a 
groove cut into a piston assisting in making 
the latter tight in the cylinder. There are 
usually three rings on each piston. (2) 
Rings about the circumference of a piston, 
whose diameter is slightly greater than that 
of the pisi on. These are to insure closer fit 
and prevent wearing of the piston, as the 
wear is taken up by the rings which may 
be easily removed. 

Piston Rod: Usually called connecting rod* 
The rod which connects the piston with 
the crankshaft. 

Piston Skirt: The portion of a piston below 
the piston pin. 

Piston Speed : The rate at which the piston 
travels in its cylinder. 

Piston Stroke: The complete distance a 
piston travels in its cylinder. 

Pitted: Condition of a working surface which 
has become covered with carbon particles 
which have been imbedded in the metal. 

Planetary Gear: An arrangement of spur 
and annular gears in which the smaller gears 
revolve around the main shaft as planets 
revolve around the sun. 

Planetary Transmission: A transmission 
system in which the speed changes are ob- 
tained by a set of planetary gears. 

Plate: Part of a storage battery which holds 
active material. See "Negative Plate". 

Pneumatic Tire: A tire fitted to the wheels 
of automobiles, consisting usually of two 
tubes, the outer of India rubber, canvas, and 
other resilient wear-resisting material, and 
the inner composed of nearly pure rubber 
which is inflated with compressed air to 
maintain the outer tube in its proper form 
under load. 

Polarizing: Formation of gas at the negative 
element of a cell so as to prevent the action 
of the battery. > This formation of gas is 
caused by the violent reaction taking place 
in a circuit of low resistance. 

Pole Piece: A piece of iron attached to the 
pole of a magneto used in an electric gener- 
ator. 

Poppet Valve: A disk or drop valve usually 
seating itself through gravitation or by 
means of springs, and frequently opening by 
suction or cams. 

Port: An opening for the passage of the 
working fluid in an engine. 

Portable Garage: See "Garage, Portable". 

Positive Connection: A connection by 
which positive motion is transmitted by 
means of a crank, bolt, or key, or other 
method by which shipping is eliminated. 

Positive Motion: Motion transmitted by 
cranks or other methods in which slipping 
is eliminated. 

Positive Plate: Plate in a storage batterv, 
from which the current flows to the outside 
circuit. 

Positive Pole: The source from which elec- 
tricity is assumed to flow; the opposite of 
negative pole. In a magnet the positive pole 
is the end of the magnet from which the 
magnetic flux is assumed to emanate. 

Pounding in Engine: Pounding noise at 
each revolution, usually caused by either 



carbon deposit, loose or tight piston, loose 
bearing or other part, or pre-ignition. 

Power Stroke: The piston stroke in a gas 
engine in which the exploded gases are 
expanding, thus pushing the piston down- 
ward. 

Power Tire Pump: A pump which is oper- 
ated by a gas engine and is used to inflate 
the tires of a motor car. 

Power Unit: The engine with fuel, cooling, 
lubrication, and ignition systems, without 
the transmission or running gears. Some- 
times the gearset and driving shaft are 
included by the term. 

Pre-Ignition : See "Premature Ignition". 

Premature Ignition: Ignition of fuel before 
the proper point in the cycle. 

Pressure-Feed: See "Lubrication, Force- 
Feed". 

Pressure Gage: A gage for indicating the 
pressure of a fluid confined in a chamber, 
such as steam in a boiler, etc. 

Pressure Lubricator: A lubricating device 
in which the oil is forced to the bearings by 
means of a pump or other device for main- 
taining pressure. 

Pressure Regulator: A device for main- 
taining the pressure of the steam in the 
principal pipe at a constant point irrespective 
of the fluctuations of pressure in the boiler. 

Primary Air Inlet: The main or fixed air 
intake of a carbureter. 

Primary Circuit: The circuit which carries 
low-tension current. 

Primary Coil: A self-induction coil consist- 
ing of several turns of wire about an iron 
core. 

Primary Spark Coil: An induction coil 
which has only a single winding composed 
of a few layers of insulated copper wiro 
wound on a bundle of soft iron wires, known 
as the core, also as a wipe, or touch, spark coil. 

Primer: A pin in a float-feed valve so 
arranged that it may depress the float in 
priming a gasoline engine. Also called 
tickler and flushing pin. 

Priming: (1) The carrying of water over 
with the steam from the boiler to the 
engine, due to dirty water, irregular evapo- 
ration, or forced steaming. (2) Injecting a 
small amount of gasoline into the cylinder 
of a gasoline engine to assist in starting. 

Priming Cock: A control cock screwed into 
the cylinder and which when open com- 
municates with the combustion chamber 
allowing gasoline to be poured into the 
cylinder. 

Progressive Change-Speed Gears : Change- 
speed gears so arranged that higher speeds 
are obtained by passing through all the 
intermediate steps and vice versa. 

Prony Brake: A dynamometer to indicate 
the horsepower of an engine. A ban I 
encircles the flywheel of the engine and is 
secured to a lever, at the other end of which 
is a scale to measure the pull. 

Propeller Shaft: The shaft which turns the 
rear axle of a motor car. The drive shaft. 

Pump, Centrifugal: A pump with a hollow 
hub and curved blades which by centrifugal 
force throw water or oil into the system 
requiring it. 

Pump, Circulation: See "Circulation 
Pump". 



418 



Digitized by 



Google 



GLOSSARY 



21 



Pump, Fuel-Feed : A mechanically oper- 
ated pump for insuring positive feed of fuel 
to the burner of a steam engine or carbureter 
of a gas engine. 

Pump, Oil: See "Oil Pump". 

Pump, Plunger: Sometimes called piston 
pump. One containing a piston which 
forces a liquid to a system. 

Pump, Power Tire: See "Tire Pump". 

Pump, Steam Boiler-Feed: See "Boiler- 
Feed Pump". 

Pump, Water Circulating: See "Circula- 
tion Pump". 

Pump Gear: A pump composed of two 
gears in mesh placed in a housing. When 
the gears revolve they carry oil or water, as 
the case may be, on their teeth, which deliver 
it to an outlet. 

Puncture: The perforation of an inflated 
rubber automobile tire by some sharp sub- 
stance on the roadbed. 

Puncture-Closing Compound: A viscous 
compound placed within the inner tire tube 
to close the hole caused by a puncture. 

Push Rod: A rod which operates the valves 
of a poppet-valve motor. A rod which 
imparts a pushing motion. 



Race: (1) The parts upon which the balls 
of a ball bearing roll. (2) When referring 
to a gas engine, to operate at high speed 
without a load. 

Racing Body: A low, light automobile body, 
having two seats with backs as low as possi- 
ble; designed for large fuel capacity and 
very high speed. 

Radiator: A device consisting of a large 
number of small tubes, through which the 
heated water from the jacket of the engine 
passes to be cooled, the heat being carried 
away from the metal of the radiator by air. 

Radiator, Cellular : See "Honeycomb 
Radiator". 

Radiator, Tubular: A radiator consisting 
of many tubes, through which water passes 
to be cooled. 

Radiator Protector: See "Bumper". 

Radius Rod : A bar in the frame of an auto- 
mobile to assist in maintaining the proper 
distance between centers. Also called 
distance rod. 

Rawhide Gear: Tooth gears, built up of 
compressed rawhide, used for high-speed 

. drive. Sometimes a metal gear is merely 
faced with rawhide for the purpose of reduc- 
ing noUe. 

Reach Rod: See "Radius Rod". 

Reciprocating Parts: The parts such as 
pistons and connecting rods which have a 
reciprocating motion. 

Rectifier, Alternating-Current: See "Cur- 
rent Rectifier". 

Relief Cock : See "Compression-Relief Cock". 

Removable Rim : See "Demountable Rim". 

Resiliency: That property of a materia 
by virtue of which it springs back or recoils 
on removal of pressure, as a spring. 

Resistance, Electrical: (1) A part of an 
electric circuit for the purpose of opposing 
the flow of the current in the circuit. (2) 
The electrical resistance of a conductor is 



that quality of a conductor by virtue of 
which the conductor opposes the passage of 
electricity through its mass. Its umt is 
the ohm. 
Retard: With reference to the ignition sys- 
tem, causing the spark to occur while the 
piston is retarding or moving downward on 
the working stroke. 

Retarding Ignition: See "Ignition, Retard- 
ing". 

Retarding the Spark: See "Ignition, Re- 
tarding". 

Retread: To replace the tread of a pneu- 
matic tire with a new one. 

Reverse Cam: On a gasoline engine a cam 
so arranged that by reversing its motion or 
shifting it along its shaft it will operate the 
valves and cause the engine to reverse. 

Reverse Gear: In a steam engine, a device 
by which the valves may be set to effect 
motion of the car in either direction. In a 
gasoline # automobile, the reversing gear is 
usually incorporated with the change-speed 
gears. 

Reverse Lever: A lever by which the direc- 
tion of movement of the driving wheels may 
be reversed without reversing the engine. 
This is usually combined with the change- 
speed levers. 

Rheostat: A device for regulating the flow 
of current in a closed electrical circuit by 
introducing a series of graduated resistances 
into the circuit. 

Rim : The portion of a wheel to which a solid 
or pneumatic tire is fitted. A circular, 
channel-shaped portion attached to the 
wheel felloe. 

Rim, Demountable: A rim which may be 
removed from the wheel easily in order that 
another with an inflated tire may take its 
place. 

Rim, Quick-Detachable: A rim made of 
two or more parts so that, the tire may be 
detached and attached quickly. 

Rim, Removable: See "Demountable Rim". 

Road Map: A map of a section or locality 
showing the best roads for motor-car travel, 
and usually the best stopping places and 
repair stations. 

Roadster: A small motor car designed to be 
fairly speedy; usually has carrying capacity 
for an extra large quantity of fuel and sup- 
plies; generally seats two persons, with pro- 
vision for one or two more, by the attach- 
ment of a rumble seat in the rear. 

Rocker Arm: A pivoted lever used to oper- 
ate overhead valves in a T-head motor 

Rod, Radius: See "Radius Rod". 

Rod, Steering: See "Steering Rod". 

Roller Bearings: See "Bearing, Roller'*. 

Roller Chain: A chain whose links are pro- 
vided with small rollers to decrease the fric- 
tion and the noise. 

Rotary Valves A type of valve somewhat 
similar to the Corliss engine valve used on 
automobile motors. 

Rumble: A small single seat to provide for 
an extra passenger on a two-seated vehicle. 
Usually detachable. 

Runabout: A small two-seated vehicle, usu- 
ally of a lower power and lower speed, as 
/ well as lower operating radius, than a road- 
star. 



419 



Digitized by 



Google 



22 



GLOSSARY 



Running Board: A horisontal step placed 
below the frame and used to assist passen- 
gers in leaving and entering a motor car. 

Running Gear: The frame, springs, motor, 
wheels, speed-change gears, axles, and 
machinery of an automobile, without the 
body; used synonymously with chassis. 

S 

Safety Plug: See "Fusible Plug". 

Safety Valve: A valve seated on the top of a 
steam boiler, and loaded so that when the 
pressure of the steam exceeds a certain point 
the valve is lifted from the seat and allows 
the steam to escape. 

Saturated Steam: The quality of the 
steam when no more steam can be made in 
the closed vessel without raising the tempera- 
ture or lowering the pressure. 

Scavenging: The action of clearing the cyl- 
inder of an internal-combustion motor of 
the burned-out gases. 

Score: To burn, or abrade a moving part 
with another moving part. 

Screw: An inclined plane wrapped around a 
cylinder; a cylinder having a helical groove 
cut in its surface. 

Searchlight: A headlight designed to throw 
a very bright light on the road. Electricity 
or acetylene is usually used as an illuminant, 
and the lamp has a parabolic reflector and 
may be turned to throw the light in any 
direction. 

Secondary Battery: See "Accumulator". 

Secondary Circuit: A circuit in which the 
electromotive force is generated by induc- 
tion from a primary circuit in which a varia- 
ble current is flowing. The high-tension 
circuit of a jump-spark ignition system. 

Secondary Circuit: The circuit which carries 
high-tension current. 

Secondary Spark Coil: An induction coil 
having a double winding urn>n its core. 
The inner winding is composed of a few 
layers of insulated wire of large size, and 
the outer winding consists of a great many 
layers of very small insulated copper wire. 
Also known as a jump-spark coil. 

Seize: Refers to moving parts which adhere 
because of operation without a film of oil 
between the working surfaces. 

Selective Change-Speed Gears: Change- 
speed gears so arranged that .any desired 
speed combination can be obtained without 
going through the intermediate steps. 

Self -Firing: Ignition of the mixture in a 
gas engine due to the walls of the cylinder or 
particles attached to them becoming over- 
heated and incandescent. 

Self-Starter: See "Engine Starter". 

Separator, Steam: A device attached to 
steam pipes to separate entrained water 
from live steam before it enters the engine, 
or to separate the oily particles from exhaust 
steam on its way to the condenser. 

Series Circuit: A compound circuit in which 
the separate sources or the separate elec- 
trical receiving devices, or both, are so 
placed that the current supplied by each, or 
passed through each, passes successively 
through the other circuits from the first to 
the last. 

Set Screw: A small screw with a pointed 
end used for locking a part in a fixed position 
to prevent it from turning. 



Setting Valves: See "Valve Setting". 

Shaft, Intermediate: The shaft placed 
between the first and third motion gearing 
and acting as a carrier of motion between 
the two. 

Shaft Drive: System of power transmission 
by means of a shaft. 

Shim: See "Liner". 

Shock Absorber: A device attached to the 
springs or hangers of motor cars to deereat e 
the jars due to rough roads, instead 01 
allowing them to be transmitted to the 
frame of the carriage. 

Short Circuit: A shunt or by-path of com- 
paratively small resistance around a portion 
of an electric circuit, by which enough cur- 
rent passes through the new path to virtu- 
ally cut out the part of the circuit around 
which it is passed, and prevent it from 
receiving any appreciable current. 

Sight Feed : An indicator covered with glass 
which shows that oil is flowing in a system. 
A telltale sight. A check on the oiling 
system. 

Side-Bar Steering: See "Steering, Side- 
Bar". 

Side -Slipping: See "Skidding". 

Silencer: See "Muffler, Exhaust". 

Silent Chain: A form of driving chain in 
which the links are comprised of sections 
which so move over the sprocket that prac- 
tically all noise is eliminated. Silent chains 
are used specially for driving timing gears, 
gearsets, etc. 

Skidding: The tendency of the rear wheels 
to slide sideways to the direction of travel, 
owing to the slight adhesion between tires 
and the surface of the roadbed, also called 
side-slipping. 

Skip: See "Miss". 

Sleeve Valve: A form of valve consisting of 
cylindrical shells moving up and down in 
the cylinders of such a motor as the Silent 
Knight. 

Sliding Gears: A change-speed set in which 
various gears are placed into mesh by the 
sliding on a shaft of one or more gears. 

Sliding Sleeve: See "Motor, Sleeve-Valve". 

Slip Cover: A fabric covering for the top 
when down or for the upholstery of a motor 
vehicle. 

Smoke in Exhaust: Smoky appearance in 
the exhaust due to too .much oil, too rich 
mixture, low grade of fuel, or faulty ignition. 

Solid Tire: See "Tire, Solid". 

Sooting of Spark Plug: Fouling of the 
spark plug with soot, due to poor mixture, 
impure fuel, or improper lubrication. 

Spare Wheel: An extra wheel complete 
with inflated tire, carried on the car for quick 
replacement of wheel with damaged tire. 

Spark, Advancing: See "Advanced Igni- 
tion". 

Spark Coil: A coil or coils of wire for pro- 
ducing a spark at the spark plug. It may 
be either a secondary or primary spark coiL 

Spark Gap: A break in the circuit of a 
jump-spark ignition system for producing a 
spark within the cylinder to ignite the 
charge. The spark gap is at the end of a 
small plug called the spark plug. 

Spark Gap, Extra: See "Spark Gap, Out- 
side". 



420 



Digitized by 



Google 



GLOSSARY 



23 



Spark Gap, Outside: A device to overcome 
the short circuiting in the spark gap due to 
fouling and carbon deposits between the 
points of the high-tension spark plug. It is 
a form of condenser, or capacity in which 
the air acts as the dielectric between two 
surfaces at the terminals of a gap in a high- 
tension circuit. 

Spark Intensifier: See "Spark Gap, Out- 
side". 

Spark Lever: See "Timing Lever". 

Spark Plug: The terminals of the secondary 
circuit of a jump-spark ignition system 
mounted to leave a spark gap between the 
terminals projecting inside the cylinder for 
the purpose of igniting the fuel in the cylin- 
der l>y means of a spark crossing the gap 
between them. 

Spark Plug, Pocketing: Mounting the 
spark plug in a recess of the cylinder head to 
reduce the sooting of the sparking points. 

Spark Plug, Sooting of: See "Sooting of 
Spark Plug". 
. Spark Regulator: A mechanism by which 
the time of ignition of the charge is varied 
by a small handle on or near the steering 
wheel. 

Spark, Retarding: See "Ignition, Retard- 
ing". 

Spark Timer: See "Timer, Ignition". 

Speaking Tube: See "Annunciator". 

Specific Gravity: The weight of a given 
substance relative to that of an equal bulk 
of some other substance which is taken as a 
standard of comparison. Air or hydrogen 
is the standard for gases, and water is the 
standard for liquids and solids. 

Specific Heat: The capacity of a substance 
for removing heat as compared with that of 
another which is taken <as a standard. The 
standard is generally water. 

Speed-Change Gear: A device whereby the 
speed ratio of the engine and driving wheels 
of the car is varied. 

Speed Indicator: An instrument for show- 
ing the velocity of the car. 

Speedometer: A device used on motor cars 
for recording the miles traveled and for 
indicating the speed at all times. 

Speedometer Gears: Gears used to drive a 
shaft which operates the speedometer. 

Speedometer Shaft: A flexible shaft which 
operates a speedometer. 

Spiral Gear: A gear with helically-cut 
teeth. 

Splash Lubrication: See "Lubrication, 

Splash". 
Spline: A key. 

Spontaneous Ignition: See "Self-Firing". 
Sprag: A device to be let down (usually at 

the rear of the car) to prevent its slipping 

back when climbing a hill. 

Spray Nozzle: That portion of a carbureter 
which sprays the gasoline. 

Spring: An elastic body, as a steel rod, 
plate, or coil, used to receive and impart 
power, regulate motion, or diminish con- 
cussion. 

Spring, Cantilever: A type of spring which 
appears like a semi-elliptic reversed; and 
which is flexibly attached in the center, 
rigidly at one end, and by a shackle at the 
other. 



Spring, Elliptic: A spring, elliptic in shape, 
and consisting of two half-elliptic members 
attached together. 

Spring Semi-Elliptic: A spring made up ot 
a number of leaves, the whole resembling a 
portion of an ellipse. 

Spring, Supplementary: See "Shock Ab- 
sorber". 

Spring, Underslung: A spring which is 
fastened under the axle instead of over it. 

Spring Hangers: See "Body Hangers". 

Spring Shackle: A link attached to one end 
of a spring which allows for flattening of the 
spring. 

Sprocket: A wheel with teeth around the 
circumference, so shaped that the teeth will 
fit into the links of a chain which drives or 
is driven by the sprocket. 

Starboard: The right-hand side of a ship or 
vessel. 

Starter, Engine: See "Engine Starter". 

Starting, Gas Engine: The operation neces- 
sary to make the engine automatically con- 
tinue its cycle of events. It usually consists 
of opening the throttle, retarding the spark, 
closing the ignition circuit, and cranking the 
engine. 

Starting Crank: A crank by which the 
engine may be given several revolutions by 
hand in order to start it. 

Starting Device: See "Engine Starter". 

Starting on Spark: In engines having four 
or more cylinder with well-fitting pistons, 
it is often possible to start the motor after it 
has stood idle for some time by simply clos- 
ing the ignition circuit, provided that the 
Erevious stopping of the engine was done 
y opening the ignition circuit before the 
throttle was closed, leaving an unexploded 
charge under compression in . one of the 
cylinders. 

Steam: The vapor of water; the hot invisible 
vapor given off by water at its boiling point. 

Steam Boiler: See "Boiler". 

Steam Condenser: See "Condenser". 

Steam, Cycle of: A series of operations of 
steam forming a closed circuit, a fresh series 
beginning where another ends; that is, 
steam is generated in the boilers, passes 
through the pipes of the engine, doing work 
successively in its various cylinders, escap- 
ing at exhaust pressure to the condenser, 
where it is converted into water and returned 
to the boiler, to go through the same opera- 
tions once more. 

Steam Engine: A motor depending for its 
operation on the latent energy in steam. 

Steam Gage: See "Pressure Gage". 

Steam Port: See "Admission". 

Steering, Side-Bar: Method of guiding the 
car by means of an upright bar at the side 
of the seat. 

Steering Angle for Front Wheels: Maxi- 
mum angle of front wheels to the axle when 
making a turn; should be about 35°. 

Steering Check: A device for locking the 
steering gear so that the direction will 
not be changed unless desired. 

Steering Column: See "Steering Post". 

Steering Gear: The mechanism by which 
motion is communicated to the front axle of 
the vehicle, by which the wheels may be 
turned to guide the car as desired. 



421 



Digitized by 



Google 



24 



GLOSSARY 



Steering Knuckle: A knuckle connecting 
the steering rods with the front axle of the 
motor. 

Steering Lerer: A lever or handle by which 
the car is guided. 

Steering Neck: The vertical spindle carried 
by the steering yoke. It is the pivot of the 
bell crank by which the wheel is turned. 

Steering Pillar: See "Steering Post". 

Steering Poet: The member through which 
the twist of the steering wheel is trans- 
mitted to the steering knuckle. The steering 
post often carries the spark and throttle 
levers also. 

Steering Rod: The rod which connects the 
steering gear with the bell cranks or pivot 
arms, by means of which the motor car is 
guided. 

Steering Wheel: The wheel by which the 
driver of a motor car guide? it. 

Steering Yoke: The Y-shaped piece in 
which the front axle terminates. The yoke 
carries the vertical steering spindle or 
steering neck. 

Stephenson Link Motion: A reversing gear 
in which the ends of the two eccentric rods 
are connected by a link or quadrant sliding 
over a block at the end of the valve spindle. 

Step-Up Coil: A coil used to transform low- 
into high-tension current. 

Storage Battery: See "Accumulator". 

Stroke: See "Piston Stroke". 

Strainer, Gasoline: A wire netting for pre- 
venting impurities entering the gasoline feed 
system. 

Strangle Tube: The narrowing of the 
throat of the carbureter just above the air 
inlets in order to increase the speed of the 
air, and thus increase the proportion of gas 
which will be picked up. 

Stroke: The distance of travel of a piston 
from its point of farthest travel at one end 
of the cylinder to its point of farthest travel 
at the other end. Two strokes of the piston 
take place to every revolution of the crank- 
shaft. 

Stud Plate: The plate or frame in a planet- 
ary transmission system carrying studs upon 
which the central pinions revolve. 

Suction Valve: The type of admission valve 
on an internal combustion engine which is 
opened by the suction of the piston within 
the cylinder and admits the mixture. The 
valve is normally held to its seat by a spring. 

Sulpha ting of Battery: The formation of 
an inactive coating of lead sulphate on the 
surface of the plates of a storage battery. 
It is a source of loss in the battery. 

Superheated Steam: Steam which has been 
still further heated after reaching the point 
of saturation. 

Supplementary Air Valve: See "Auxiliary 
Air Valve". 

Swivel Joint: The joint for connecting the 
steering arm of the wheel or lever-steering 
mechanism to the arms on the steering 
wheel. Also called knuckle joint. 



Tachometer: An instrument for indicating 
the number of revolutions made by a machine 
in a unit of time. 

Tandem Engine: A compound engine hav- 
ing two or more cylinders in a line, one 



behind the other, and with pistons attach* 4 
to the same piston rod. 

Tank Gage: See "Fuel-Level Indicator". 

Tappet Rod: See "Push Rod". 

Taxicab: A public motor-driven vehicle in 
which the fare is automatically registered by 
the taximeter. 

Taximeter: An instrument in a public 
vehicle for mechanically indicating the fare 
charged. 

Terminals: The connecting posts of elec- 
trical devices, as batteries or coils. 

Thermal Unit: Usually called the British 
Thermal Unit, or B. t. u. A measure of 
mechanical work equal to the energy re- 

auired to raise one pound of water one 
egree Fahrenheit. 

Thermostat: An instrument to automati- 
cally regulate the temperature. 

Thermoeiphon Cooling: A method of cool- 
ing the cylinder of a gas engine. The water 
rises from the jackets and siphons into a 
radiator from whence it returns to the 
supply tank, doing away with the necessity 
for a circulating pump. 

Three-Point Suspension: A method used 
for suspending motor car units, such as the 
motor, on three points. 

Throttle: A valve placed in the admission 
pipe between the carbureter and the admis- 
sion valve of the motor to control the speed 
and power of the motor by varying the 
supply of the mixture. 

Throttle, Foot: See "Accelerator". 

Throttle, Lever: A lever on the steering 
wheel which operates the carbureter throttle. 

* See "Throttle*. 

Throttling: The act of closing the admission 
pipe of the engine so that the gas or steam is 
admitted to the cylinder less rapidly, thus 
cutting down the speed and power of the 
engine. 

Thrust Bearing: A bearing which takes 
loads parallel with the axis of rotation of the 
shaft upon which it is fitted. 

Tickler: A pin in a carbureter arranged to 
hold down the float in priming, also called 
flushing pin and primer. 

Timer, Ignition: An ignition commutator. 

Timing Gears: The gears which operate the 
camshaft and magneto shaft. The camshaft 
gear is twice as large as the crankshaft geai. 

Timing Lever: A lever fitted to gas engines 
by means of which the time of ignition is 
changed. Also called spark lever. 

Timing Valve: In a gas engine using float- 
tube ignition, a valve controlling the opening 
between the combustion space and the 
igniter. 

Tip, Burner: A small earthen, aluminum, or 
platinum cover for the end of the burner 
tube of an acetylene lamp. It is usually 
provided with two holes, so placed that the 
jets from them meet and spread out in a 
fan shape. 

Tire, Airless: See "Airless Tire". 

Tire, Clincher: A type of pneumatic tire 
which is held to a clincher. 

Tire, Cushion: Vehicle tire having a very 
thick rubber casing and very small air space. 
It is non-puncturable and does not have to 
be inflated, but is not as resilient as a pneu- 
matic tire. 



422 



Digitized by 



Google 



GLOSSARY 



25 



Tire, Non-Delia table: See "Tire, Non- 
Puncturable". 

Tire, Non Punc titrable: A tire so construct- 
ed that it cannot be easily punctured or will 
not become deflated when punctured. 

Tire, Punctures ir» : Holes or leaks in pneu- 
matic tires caused by foreign substances 
penetrating the inner tube and allowing the 
air to escape. 

Tire, Single-Tube: A pneumatic tire in 
which the inner and outer tubes are com- 
bined. 

Tire, Solid: A tire made of solid, or nearly 
solid rubber. 

Tire Band: A band to protect or repair a 
damaged pneumatic tire. See "Tire Pro- 
tector". 

Tire Bead: Lower edges of a pneumatic "ire 
which grip the curved portion of a rim. 

Tire Case: (1) A leather or metal case tor 
carrying spare tire; same as tire holder, 
(2) The outer tube. 

Tire Chain: See "Anti-Skid Device". , 

Tire Filling: Material to be introduced into 
the tire to take the place of air and do away 
with puncture troubles 

Tire Gage: Gage used for measuring the air 
pressure in a pneumatic tire. 

Tire Holder: A metal or leather case for 
carrying spare tires. 

Tire-Inflating Tank: A tank containing 
compressed air or gas for inflating the tires. 

Tire Inflater, Mechanical: A small mechan- 
ical pump for inflating pneumatic tires. 

Tire ^atch: See "Patch, Tire Repair". 

Tire-Pressure Gage: A pressure gage to 
indicate the pressure of air in the tire. 

Tire Protector: The sleeve or band placed 
over a tire to protect it from road wear. 

Tire Pump: A pump for furnishing air under 
pressure to the tire, may be either hand- or 
power-operated. 

Tire Sleeve: A sleeve to protect the injured 
part of a pneumatic tire. It is a tire pro- 
tector which covers more of the circumfer- 
ence of the wheel than a tire band. See 
"Tire Protector". 

Tire Tape: Adhesive tape used to bind the 
outer tube to the rim in repairing tires. 

Tire Tool: Tool used to apply and remove a 
tire. 

Tire Valve: A small valve in the inner tube 

to allow air to be pumped into the tube 

without permitting it to escape. 
Tires, Creeping of: See "Creeping of Tires". 
Tonneau: The rear seats of a motor car. 

Literally, the word means a round tank or 

water barrel. 

Torque: Turning effort, or twisting effort of 
a rotating part. 

Torque Rod: A rod attached at one end to 
the rear axle and at the other to the frame; 
used to prevent twisting of the rear-axle 
housing. 

Torsion Rod: Thj shaft that transmits the 
turning impulse from the change gears to 
the rear axle. Usually spoken of as the 
shaft. 

Touch Spark: See "Wipe Spark". 
Tourabout: A light type of touring car. 
Touring Car: A car with no removable rear 



seats, and a carrying capacity of four to 
seven persons. 

Town Car: A car having the rear seats 
enclosed but the driver exposed. 

Traction: The act of drawing or state of 
being drawn. The pull (or push) of wheels 

Tractor: A self propelled vehicle for hauling 
other vehicles or implements; a traction 
engine. 

Transmission, Individual Clutch: A 
transmission consisting of a set of spur gears 
on parallel shafts which are always in mesh, 
different trains being picked up with a 
separate clutch for each set. 

Transmission, Planetary: A transmission 
system in which a number of pinions revolve 
about a central pinion in a manner similar to 
the revolution of the planets about the sun; 
usual type consists of a central pinion sur- 
rounded by three or more pinions and an 
internal gear. 

Transmission, Sliding Gear: A trans- 
mission system in which sliding change-speed 
gears are used. 

Transmission Brake: Brake operating on 
the gearset shaft or end of the propeller shaft. 

Transmission Gears: A set of gears by 
which power is transmitted. In automo- 
biles, usually called change-speed gears. 

Transmission Ratio: The ratio of the speed 
of the crankshaft to the speed of the trans- 
mission shaft or driving shaft. 

Tread: That part of a wheel which comes in 
contact with the road. 

Tread, Detachable: A tire covering to pro- 
tect the outer tube, which may be taken off 
or replaced. 

Trembler: The vibrating spring actuated by 
the induction coil magnet which rapidly 
connects and disconnects the primary circuit 
in connection with jump-spark ignition. 

Truck: (1) A strong, comparatively slow- 
speed vehicle, designed for transporting 
heavy loads. (2) A swiveling carriage 
having small wheels, which may be placed 
under the wheels of a car. 

Try Cock: A faucet or valve which may be 
opened by hand to ascertain the height of 
water in the boiler. 

Tube Case: See "Tire Case". 
Tube Ignition: See "Hot- Tube Ignition". 
Tubing, Flexible: See "Flexible Tubing". 
Tubular Radiator: An automobile radiator 

in which the jacket water circulates in a 

series of tubes. 

Tungsten Lamp: Incandescent bulb with 
the filament made of tungsten wire. 

Turning Moment: See "Torque". 

Turning Radius: The radius of a circle 
which the wheels of a car describe in making 
its shortest turn. 

Turntable: Device installed in the floor of a 
garage and used for turning motor cars 
around. 

Two-Cycle or Two-Stroke Cycle Engine: 

An internal-combustion engine in which an 
impulse occurs at the beginning of every 
revolution, that is, at the beginning of every 
downward stroke of the piston. 

Two- to-One Gear: The system of gearing in 
a four-cycle gas engine for driving the cam- 
shaft, which must revolve once to every two 
revolutions of the crankshaft. 



423 



Digitized by 



Google 



26 



GLOSSARY 



u 

Under Frame: The main frame of the 
chassis or running gear of a motor vehicle. 

Unit-Power Plant: A power system consist- 
ing of a motor, gearset, and clutch which 
may be removed from the motor car as a 
unit. 

Universal Joint: A mechanism for endwise 
connection of two shafts so that rotary 
motion may be transmitted when one shaft 
is at an angle with the other. Also called 
universal coupling, flexible coupling, Cardan 
joint and Hooke's joint. 

Upkeep: The expenditure for maintenance 
or expenditure required to keep a vehicle in 
good condition and repair. 



Vacuum Fuel Feed : A system of feeding the 
gasoline from a tank at the rear of an auto- 
mobile by maintaining a partial vacuum at 
some point in the system, usually at the dash, 
the fuel flowing from this point by gravity to 
the carbureter. 

Vacuum Line: In an indicator diagram, the 
line of absolute vacuum. It is at a distance 
corresponding to 14.7 pounds below the 
atmospheric line. 

Valve: A device in a passage by which the 
flow of liquids or gases may be permitted or 
stopped. 

Valve, Admission: The valve in the admis- 
sion pipe of the engine leading from the car- 
bureter to the cylinder by which the supply 
of fuel may be cut off. 

Valve, Automatic: See "Automatic Valve". 

Valve, Inlet: See "Inlet Valve". 

Valve, Mixing: See "Mixing Valve". 

Valve., Muffler Gut-Out: See "Cut-Out, 
Muffler". 

Valve, Overhead: See "Overhead Valve". 

Valve, Poppet: See "Poppet Valve". 

Valve, Rotary: See "Motor, Rotary Valve"* 

Valve, Suction: An admission valve which 
is opened by the difference between the pres- 
sures in the atmosphere and in the cylinder. 

Valve Gage: A valve-retaining pocket which 
is attached to the cylinder. 

Valve Clearance: The clearance of play 
between the valve stem and the tappet. 

Valve Gear: The mechanism by which the 
motion of the admission or exhaust valve is 
controlled. 

Valve Grinding: The act of removing marks 
of corrosion, pitting, etc., from the seats and 
faces of poppet or disk valves. The surfaces 
to be ground are rotated in contact with each 
other, an abrasive having been supplied. 

Valve Lift: See "Lift". 

Valve Lifter: A device for raising a poppet 
valve from its seat. 

Valve Seat: (1) That portion of the engine 
upon which the valve rests when it is closed. 
(2) The portion upon which the face of a 
valve is in contact when closed. 

Valve Setting: The operation of adjusting 
the valves of an engine so that the events of 
the cycle occur at the proper time. Also 
called valve timing. 

Valve Spring: The spring which is around 
the valve stem and is used to return the 



valve to closed position after it has been 
opened by the cam: 

Valve Stem : The rod-like portion of a poppet 
valve. 

Valve Timing: See "Valve Setting". 

Vaporizer: A device to vaporize the fuel for 
an oil engine. In starting it is necessary to 
heat the vaporiser, but the exhaust gases 
afterwards keep it at the proper tempera- 
ture. The carbureter of the gas engine 
properly belongs under the general head of 
vaporizer, but the term has become restricted 
to the vaporiser for oil engines. 

Variable-Speed Device: See "Gear, Change- 
Speed". 

Vertical Motor: An upright engine whose 
piston travel is in a vertical plane. 

Vibrator: The part of the primary circuit of 
a jump-spark ignition system by which the 
circuit is rapidly interrupted to give a trans- 
former effect in the coil. 

Vibrator, Master: See "Master Vibrator". 

Volatile: Passing easily from a liquid to a 
gaseous state, in opposition to fixed. 

Volatilization: Evaporation of liquids upon 
exposure to the air at ordinary temperatures. 

Volt: Practical unit of electromotive force; 
such an electromotive force as would cause 
a current of one ampere to flow through a 
resistance of one ohm. 

Voltammeter: A voltmeter and an ammeter 
combined; sometimes refers to wattmeter. 

Voltmeter: An instrument for measuring 
the difference of electric potential between 
the terminals of an electric circuit. It 
registers the electric pressure in volts. 

Vulcanization: The operation of combining 
sulphur with rubber at a high temperature, 
either to make it soft, pliable, and elastic, oi 
to harden it. 

Vulcanizer: A furnace for the vulcanisation 
of rubber. 

W 

Walking Beam: See "Rocker Arm". 

Water Cooling: Method of removing the 
heat of an internal-combustion motor fiom 
the cylinders by means of a circulation of 
water between the cylinders and the outer 
casing. 

Water Gage: An instrument used to indicate 
the height of water within a boiler or other 
water system. It consists of a glass tube 
connected at its upper and lower ends with 
the water system. 

Water Jacket: A casing placed about the 
cylinder of an internal-combustion engine to 
permit a current of water to flow around it 
for cooling purposes. 

Watt: The unit of electric power. It is the 
product of the current in amperes flowing in 

a circuit by the pressure in volts. It is =7? 

746 

of a horsepower. 

Watt Hour: The unit of electrical energy. 
The given watt-hour capacity of a battery, 
for instance, means the ability of a battery 
to furnish one watt for the given number of 
hours or the given number of watts for one 
hour, or a number of watts for a number of 
hours such that their product will be the 
given watt hours. 

Welding, Autogeneous: A method of joining 
two pieces of metal by melting by means of a 



424 



Digitized by 



Goo 



'8 



A 



GLOSSARY 



27 



blow torch burning acetylene in an atmos- 
phere of oxygen. This melts the ends of the 
parts and these are then run together. 
Wheel, Artillery: A wood-spoked wheel 
whose spokes are in line with a line drawn 
vertically through the hub. 

Wheel, Dished: A wheel made concave or 
convex so that the hub is inside or outside as 
compared with the rim. This is to counter- 
act the outward inclination of the wheel due 
to the fact that the spindle is tapered and 
that its outward center is lower than its 
inner center. 

Wheel, Double-Interacting: The mecha- 
nism by which two wheels are hung on one 
hub or axle, the outer being shod with an 
ordinary solid tire and the inner with a 
pneumatic tire, so that the weight of the 
vehicle bears against the lowest point of the 
pneumatic tire of the inner wheel to give the 
durability and tractive properties ofa solid 
tire with the resiliency, of a pneumatic. 

Wheel, Spare: See "Spare Wheel". 

Wheel Steeling: See "Steering Wheel". 

Wheel, Wire: A wheel with spokes made of 
wire. 

Wheel Puller: A device used for pulling 
automobile wheels from their axles. 

Wheel Steer: A method of guiding a car by 
means of a hand wheel. 

Wheel. Steering Angle for: The angle 
which the steering column makes with the 
horizontal. It varies from 90° to 30° or less. 

Wheelbase: The distance between the road 
contact of one rear wheel with the point of 
road contact of the front wheel on the same 
side. 

Wheels, Driving on All Four: The method 
of using all four wheels of an automobile as 
the driving wheels. 

Wheels, Driving on Front: The method of 
using the two front wheels as the drivers. 

Wheels, Steering on Rear: Method of 
guiding the vehicle by turning the rear 
wheels. 



Whistle: An automobile accessory oonslBting 
of a signalling apparatus giving a loud or 
harsh sound. Also called a horn. 

Wind Guard: See "Wind Shield". 

Wind Shield: A glass front placed upright 

on the dash to protect the occupants of the 

car from the wind. 

Wipe Spark: Form of primary sparking 
device in which a spark is produced by a 
moving terminal sliding over another ter- 
minal, the break thus made causing a spark. 
Also called touch spark. 

Wipe-Spark Coil: A primary spark coil 
with which the spark is made by wiping 
contact. 

Wire Drawing: The effect of steam passing 
through a partially closed valve or other 
constricted opening; so called from the thin- 
ness of the indicator diagram. 

Working Pressure: The safe wot '.ring pres- 
sure of a boiler, usually estimated as \ of 
the pressure at which a boiler will burst. 

Worm: A helical screw thread. 

Worm and Sector: A worm gear in which 
the worm wheel is not complete but is only 
a sector. Used especially in steering 
devices. 

Worm Drive: A form of drive using worm 
gears. See "Gears, Worm". 

Worm Gear: The spiral gear in wLioh a 

worm or screw is used to rotate a wheel 
Worm Wheel: A wheel rotated by a worm. 
Wrist Pin: See "Piston Pin". 



X Spring: A vehicle spring composed of two 
laminated springs so placed one upon the 
other that they Form the letter X. 



Yorke, Steering: See "Steering Yoke", 



125 



Digitized by 



Google 



Digitized by VjOOQIC 



INDEX OF WIRING DIAGRAMS 



Diagrams with Plate Numbers Are Blueprints Placed in Numerical Order 
throughout Volumes III and IV; Numbers Opposite Remaining Diagrams 
Refer to Bottom Folio in the Volumes Noted. 

A 

Abbott-Detroit 1917, Model 6-44— Remy System Vol. Ill, Plate 1 

Abbott-Detroit 1917— Remy Ignition, S. & L. System Vol. IV, Page 42 

Ahrens-Fox— Delco System Vol. Ill, Plate 2 

Allen 1916, Model 37— Westinghouse System. Vol. IV, Page 148 

Alter 1915-16— Remy System Vol. Ill, Plate 3 

Apperson — Bijur System Vol. Ill, Page 292 

Apperson, Anniversary Model — Bijur System Vol. Ill, Plate 4 

Apperson 6-16, 8-16, 6-17, and 8-17— Remy System Vol. Ill, Page 301 

Apperson 1916-17-18— Remy System Vol. IV, Page 41 

Apperson, Model 8-18- A — Remy System. Vol. Ill, Plate 5 

Atlas Three-Quarter Ton Truck— Remy System Vol. Ill, Plate 6 

Auburn, Models 4-40, 4-41, 6-45, 6-46— Remy System Vol. Ill, Plate 7 

Auburn 6-40— Delco Single-Unit System Vol. Ill, Page 253 

Auburn 1916, Models 4-38, 6-38, 6-40— Remy System Vol. IV, Page 40 

Auburn 1917-18, 6-39— Remy System Vol. IV, Page 39 

Auburn 6-44— Delco System Vol. Ill, Page 321 

Austin 12-Cylinder— Delco System Vol. Ill, Page 322 

B 

Briggs-Detroit 8-Cylinder — Remy System Vol. Ill, Plate 8 

Briscoe 1917— Auto-Lite System Vol. Ill, Page 267 

Buick 1914, Model B-54-55— Wiring Diagram, Delco System Vol. Ill, Plate 10 

Buick 1914, Model B-54-55— Circuit Diagram, Delco System Vol. Ill, Plate 11 

Buick, Models C24 and C25— Delco System Vol. Ill, Page 340 

Buick, Models C36 and C37— Delco System Vol. Ill, Page 341 

Buick 1916— Delco System Vol. Ill, Page 342 

Buick, Models D-44-45-46-47— Delco System Vol, III, Page 34£ 

Buick 1916, Model D-54-55— Delco System Vol. Ill, Plate 12 

Buick, Models D-34-35— Delco System Vol. Ill, Page 343 

Buick, Models E-34-35 and E-4 Truck— Delco System Vol. Ill, Plate 9 

Buick 4-6 Cylinder 1919, Models 44-50 — Circuit Diagram, 

Delco System Vol. Ill, Plate 13 

Buick 1920, Export, Models KX-44, 45, 49— Delco System . . Vol. Ill, Plate 13A 

C 

Cadillac 1912— Generator Circuits, Delco System Vol. Ill, Page 336 

Cadillac 1914— Delco System Vol. Ill, Page 338 

Cadillac 1915— Delco System Vol. Ill, Page 339 



427 

Digitized by 



Google 



2 INDEX 

Cadillac 1919, Model 57— Delco System Vol. Ill, Plate 13B 

Cadillac 1920, All Open Cars— Delco System Vol. Ill, Plate 13C 

Cadillac 1920, Model 59— Delco System Vol. Ill, Plate 13D 

Cadillac, Model 53— Delco System Vol. Ill, Page 347 

Cadillac, Model 55— Delco System Vol. Ill, Page 348 

Cartercar 1914, Model 7 — Circuit Diagram, Delco System.. . Vol. Ill, Plate 14 
Cartercar 1914, Model 7 — Wiring Diagram, Delco System. . . Vol. Ill, Plate 15 
Cartercar 1915, Model 9 — Circuit Diagram, Delco System.. . Vol. Ill, Plate 16 

Case 1915, Model "30"— Westinghouse System Vol. Ill, Plate 17 

Case 1917— Auto-Lite System Vol. Ill, Plate 18 

Chalmers 1915, Model 29— Westinghouse System Vol. Ill, Plate 19 

Chalmers 1916-17 — Remy Ignition and Westinghouse S. & L. 

System Vol, IV, Page 43 

Chalmers 1918 — Remy Ignition and Westinghouse S. & L. 

System Vol. IV, Page 44 

Chalmers 1917-18, Model 6-30— Westinghouse System. Vol. Ill, Plate 20 

Chandler 1917 — Regular Series, Gray & Davis System Vol. Ill, Page 411 

Chandler 1917 (Serial 35001-60000)— Gray & Davis System Vol. Ill, Page 412 

Chandler 1920— Westinghouse System ' Vol. Ill, Plate 20A 

Chevrolet — Auto-Lite System Vol. Ill, Page 255 

Chevrolet 490— Auto-Lite Single-Wire System. Vol. Ill, Page 268 

Chevrolet, Model F— Auto-Lite System Vol. Ill, Page 271 

Chevrolet, Model FB— Auto-Lite System Vol. Ill, Plate 23 

Chevrolet, Model D— Auto-Lite System Vol. Ill, Plate 21 

Chevrolet, Model "F- A"— Auto-Lite System Vol. Ill, Plate 22 

Chevrolet 1918, Models D-4 and D-5— Remy System Vol. Ill, Plate 24 

Chevrolet 1920, Model FB — Remy Ignition and Auto-Lite 

S. & L. System. Vol. Ill, Plate 23A 

Cole 1913, Models 4-40, 4-50 and 6-60— Wiring Diagram, 

Delco System Vol. Ill, Plate 30 

Cole 1913, Model 4-40— Circuit Diagram, Delco System Vol. Ill, Plate 31 

Cole 1914 4-6 Cylinder— Circuit Diagram, Delco System. . . . Vol. Ill, Plate 25 

Cole 1914 4-Cylinder— Wiring Diagram, Delco System Vol. Ill, Plate 26 

Cole 1914 6-Cylinder— Wiring Diagram, Delco System Vol. Ill, Plate 27 

Cole 1915, Model 4-40— Circuit Diagram, Delco System Vol. Ill, Plate 28 

Cole 1915, Model 6-50— Circuit Diagram, Delco System Vol. Ill, Plate 29 

Cole, Model 860— Delco System Vol. Ill, Page 325 

Cole, Model 880— Delco System Vol. Ill, Page 326 

Cole 1918, Model 870— Circuit Diagram, Delco System Vol. Ill, Plate 32 

Cole 1919, Model 870 (Serial 51001-54000)— Delco System. Vol. Ill, Plate 32A 
Cole 1920, Model 870 (Serial 57200 and up)— Delco System. . Vol. Ill, Plate 32B 

Commerce, Model E — Remy System Vol. Ill, Plate 33 

Crow-Elkhart 1916, Model 30— Dyneto System. Vol. Ill, Plate 34 

Crow-Elkhart 1916-17, Model C 23— Dyneto System Vol. Ill, Plate 35 

Cunningham 1913-14, Model "M"— North East System Vol. Ill, Plate 36 

Cunningham, Model "M" — Hearse and Ambulance Equip- 
ment, North East System Vol. Ill, Plate 37 

Cunningham, Model V-3— Delco System Vol. Ill, Plate 38 

Cunningham, Model V — Westinghouse System Vol. IV, Page 143 



,Goo 9 Ie 



Digitized by VjOOQI 



INDEX 3 

D 

Daniels Eight, 1917— Westinghouse System Vol. IV, Page 138 

Daniels 1920, Model D-19— Delco System Vol. Ill, Plate 38A 

Davis, Models 6-H, 6-1, 6-K— Delco System Vol. Ill, Page 329 

Davis, Model 6-J— Delco System Vol. Ill, Page 330 

Delco — Diagram Showing Method of Locating Breaks in 

Wires Vol. Ill, Page 363 

Delco — Diagram Showing Method of Locating Grounds Vol. Ill, Page 360 

Delco — Diagram Showing Method of Locating Short Circuits Vol. Ill, Page 361 
Delco— Pictorial Chart of Single-Unit, Single-Wire System . . Vol. Ill, Page 206 
Delco — Typical Wiring Diagram for Single-Unit, Single- Wire 

System Vol. Ill, Page 251 

Delco— 6-24 Volt Systems, Typical Wiring Diagram of Start- 
ing Motor Circuit Vol. Ill, Page 337 

Dodge— Layout of North East System Vol. IV, Page 24 

Dodge 1915— North East System Vol. Ill, Plate 39 

Dodge 1917— North East Single-Wire Vol. IV, Page 29 

Dorris 1920, Model 6-80— Westinghouse System Vol. Ill, Plate 39A 

Dort 1916-17 — Two-Brush Wiring Diagram for Connecticut 

Ignition and Westinghouse S. Systems Vol. IV, Page 144 

Dort 1916-17 — Three-Brush Wiring Diagram for Connecticut 

Ignition and Westinghouse S. Systems Vol. IV, Page 147 

Dort, Models 4 and 5 — Splitdorf-Apelco System Vol. Ill, Plate 41 

Dort 1917 — Wiring Diagram for Three-Brush Generator 

(New Style), Westinghouse System Vol. Ill, Plate 40 

Dyneto — One- Wire System, Typical Diagram Vol. Ill, Page 397 

Dyneto — Two- Wire System, Typical Diagram Vol. Ill, Page 397 

E 

Elcar, Models D4, E4, G4, D6, E6, G6— Dyneto System. . . . Vol. Ill, Plate 42 

Elgin, Model 6-E-16— Delco System Vol. Ill, Page 333 

Elgin 1917 Sixes— Wagner System Vol. IV, Page 117 

Elgin Six 1917— Wagner System Vol. Ill, Plate 43 

Elgin 1918— Wagner System Vol. IV, Page 118 

Elgin 1920, Model H— Wagner 6-Volt System Vol. Ill, Plate 43A 

Elkhart 1917— Delco System Vol. Ill, Page 334 

Elkhart 1920, Models G, H, K, D, (Serial 15000 and up)— 

Delco System Vol. Ill, Plate. 43B 

Empire 1915, Model 31— Remy System Vol. Ill, Plate 44 

Empire 1916, Model 33— Remy System Vol. Ill, Plate 45 

Enger 12-Cylinder 1916-17— Circuit Diagram, Remy System Vol. Ill, Plate 46 

Essex 1919, Model A— Delco System Vol. Ill, Plate 46A 

Essex 1920, Model A— Delco System Vol. Ill, Plate 46B 

F 

Ford 1919 Cars— Ford Starting System Vol. IV, Page 155 

Ford 1918-19 Cars— Gray & Davis System (See Gray & 
Davis) 



429 



4 INDEX 

Franklin, Series 8 — Dyneto System Vol. Ill, Page 393 

Franklin, Series 9— Dyneto System Vol. Ill, Page 394 

G 
Grant 1916-17, Model K— Remy Ignition and Wagner S.&L. 

Systems Vol. IV, Page 45 

Grant Six 1918— Wagner System Vol. IV, Page 124 

Grant 6-Cylinder 1919, Model G— Wagner System Vol. Ill, Plate 47 

Gray & Davis — Wiring Diagram for Single- Wire System with 

Grounded Motor Vol. Ill, Page 406 

Gray & Davis — Wiring Diagram for Single- Wire System with 

Grounded Switch Vol. Ill, Page 408 

Gray & Davis — Wiring Diagram for Dynamo and Regulator Vol. Ill, Page 416 
Gray & Davis Ford — Plan View of Complete Wiring System Vol. IV, Page 166 
Gray & Davis Ford — Complete Wiring System Simplified . . . Vol. IV, Page 167 
Gray & Davis Ford — Pictorial View of Wiring Diagram Vol. IV, Page 168 

H 
HAL 1917 12-Cylinder — Remy Ignition and Westinghouse 

Systems Vol. IV, Page 49 

HAL 12-Cylinder, Model 21 — Remy Ignition and Westing- 
house S. & L. Systems Vol. IV, Page 133 

Harroun, Model AA1 — Remy System Vol. IV, Page 60 

Harroun 1918— Remy System Vol. Ill, Plate 48 

Haynes Light Six — Leece-Neville System Vol. IV, Page 14 

Haynes 1916-17— Remy System Vol. IV, Page 46 

Haynes 1917 Light Six— Leece-Neville System Vol. IV, Page 17 

Haynes, Models 33, 34, 35, 36 and 37— Remy System Vol. Ill, Plate 49 

Haynes, Models 40, 40-R, 41— Delco System Vol. Ill, Page 353 

Haynes 1920 Light Twelve— Leece-Neville System Vol. Ill, Plate 49A 

Hollier Eight — Atwater-Kent Ignition and Splitdorf S. & L. 

Systems Vol. IV, Page 93 

Hudson 1914, Model 6-40— Circuit Diagram, Delco System Vol. Ill, Plate 50 
Hudson 1914, Model 6-54— Circuit Diagram, Delco System Vol. Ill, Plate 51 
Hudson 1915, Model 6-40— -Circuit Diagram, Delco System Vol. Ill, Plate 52 
Hudson 1915, Model 6-54— Circuit Diagram, Delco System Vol. Ill, Plate 53 
Hudson 1916, Model 6-40 — Circuit Diagram, Delco System Vol. Ill, Plate 54 

Hudson 1917 Super Six— Delco System Vol. Ill, Page 354 

Hudson 1919-20 Super Six, Model O— Delco System Vol. Ill, Plate 54A 

Hupmobile— Bijur System Vol. Ill, Page 291 

Hupmobile, Series N 1916-17 — Westinghouse System Vol. IV, Page 137 

I 

Interstate, Model T F— Remy System. . . .' Vol. Ill, Plate 55 

Interstate, Model T R— Remy System Vol. Ill, Plate 56 

Interstate 1916-17— Remy System Vol. IV, Page 53 

J 

Jackson Wolverins "349"— Auto-Lite System Vol. Ill, Page 272 

Jackson 1915, Model 6-40 — Circuit Diagram, Delco System. Vol. Ill, Plate 57 



430 

Digitized by 



Googk 



INDEX 

Jeffery Chesterfield Six 1916— Bijur Two-Wire System. Vol. Ill, Page 256 

Jeffery Chesterfield Six— Bijur Two-Wire System Vol. Ill, Page 289 

Jeffery Six, Model 671— Bijur System Vol. Ill, Page 297 

Jordan Sixty— Bijur System Vol. Ill, Page 286 

Jordan 1920, Model F— Delco System Vol. Ill, Plate 57A 

Jordan 1920, Model F, Series 2— Delco System Vol. Ill, Plate 57B 

Jordan 1920, Model M— Delco System Vol. Ill, Plate 570 

K 

King 1915— Ward-Leonard System. .'. Vol. Ill, Plate 58 

King 1916— Ward-Leonard System Vol. Ill, Plate 59 

King 8-Cylinder, Model EE— Bijur System Vol. Ill, Page 285 

King, Model EE and F— Bijur System Vol. Ill, Plate 60 

Kissel 191.5, Model 4-36— Westinghouse System Vol. Ill, Plate 61 

Kissel 1915, Model 6-42— Westinghouse System Vol. IV, Plate 62 

Kissel 100 Point Six 1917— Westinghouse System Vol. IV, Plate 64 

Kissel 1916, Models 4-32 and 4-36— Westinghouse System.. . Vol. IV, Plate 63 
Kissel 100 Point Six 1916— Remy Ignition and Kissel S.&L. 

Systems Vol. IV, Page 54 

Kissel 12-Cylinder 1917— Delco System Vol. Ill, Page 357 

Kissel 100 Point Six 1918— Circuit Diagram, Remy System Vol. IV, Plate 65 

Kline 1916, Model 6-36— Westinghouse System Vol. IV, Plate 66 

Krit 1915— Layout of North East 12-Volt System Vol. IV, Page 25 

L 

Leece-Neville — Generator and Circuit-Breaker Circuits Vol. IV, Page 15 

Lexington, Series 6-0-17 and 6-00-17 — Connecticut Ignition 

and Westinghouse S. & L. Systems Vol. IV, Page 134 

Liberty 1917— Delco System Vol. Ill, Page 358 

Locomobile 1911 and 1912— Bosch-Rushmore System Vol. IV, Plate 67 

Locomobile 1913, Models "38" and "48"— Westinghouse 

System Vol. IV, Plate 68 

Locomobile 1915 Closed Car — Westinghouse System Vol. IV, Plate 69 

Locomobile, Series 2, 6-Cylinder, Models 38 and 48 — West- 
inghouse System Vol. IV, Page 132 

M 

Madison, Model 18 — Circuit Diagram, Remy System Vol. IV, Plate 70 

Marion-Handley Six, 1917 — Westinghouse System Vol. IV, Page 150 

Marmon, Model 34 — Bosch-Rushmore System Vol. Ill, Page 313 

Marmon 1920, Model 34-B— Delco System Vol. IV, Plate 70A 

Maxwell 1916-17— Complete Wiring Diagram Vol. IV, Page 80 

Maxwell 1916-17 — Complete Wiring Diagram, Showing De- 
tails of Dash Panel and Batteries Vol. IV, Page 81 

Maxwell 1917 Truck— Auto-Lite System Vol. IV, Plate 71 

Maxwell 1918— Pictorial Chart of Simms-Huff System Vol. IV, Page 83 

Maxwell 1918— Simms-Huff System ; Vol. IV, Page 84 

McLaughlin Care — Remy System Vol. IV, Page 63 



431 



6 INDEX 

Mercer — Bosch-Rushmore Starter Vol. Ill, Page 311 

Mercer, Series 22-70— Bosch Ignition and U. S. L. S. & L. 

Systems Vol. Ill, Page 314 

Mercer 1917 Cars— U.S.L. System Vol. IV, Page 106 

Metz 1918— Gray & Davis System Vol. IV, Plate 72 

Mitchell 1917, Model D-40— Mitchell-Splitdorf System Vol. IV, Page 94 

Mitchell, Model C-42— Circuit Diagram, Remy System Vol. IV, Plate 73 

Mitchell-Lewis 1914-15 — Circuit Diagram, Remy System. . . Vol. IV, Plate 74 

Moline Tractor, Model D— Remy System Vol. IV, Plate 75 

Moon 1914, Model 42— Circuit Diagram, Delco System Vol. IV, Plate 76 

Moon 1914, Model 42— Wiring Diagram, Delco System Vol. IV, Plate 77 

Moon 1914, Model 6-50— Circuit Diagram, Delco System. . . Vol. IV, Plate 78 
Moon 1915, Model 4-38— Circuit Diagram, Delco System. . . Vol. IV, Plate 79 
Moon 1916, Models 6-40 and 6-30 — Circuit Diagram, Delco 

System Vol. IV, Plate 80 

Moon, Model 6-43— Delco System Vol. Ill, Page 365 

Moon, Model 6-66— Delco System Vol. Ill, Page 366 

N 

Nash, Model 681— Delco System Vol. Ill, Page 369 

Nash Model Truck— Delco System Vol. IV, Plate 81 

Nash 1919, Models 681, 682— Delco System Vol. IV, Plate 80A 

National Highway 12 — Delco Ignition and Bijur Starter .... Vol. Ill, Page 298 
National Highway 6, 1917-18 — Delco Ignition and Westing- 
house Starter Vol. IV, Page, 149 

National Six — Wiring Diagram for Remy Double-Deck Unit Vol. IV, Page 71 

National 12-Cylinder, Series A-K— Delco System Vol. Ill, Page 370 

National, Series AF3— Delco System Vol. IV, Plate 82 

National 1920, Series BB (Serial 60001 and up)— Westing- 
house System Vol. IV, Plate82A 

North East— Wiring Diagram for 16- Volt Vol. IV, Page 26 

North East — Wiring Diagram for 24- Volt System Using 

7-Volt Lamps Vol. IV, Page 27 

North East Model "D" Starter-Generator — Internal Wiring 

Diagram Vol. IV, Page 31 

North East Model "B" Starter-Generator — Internal Wiring 

Diagram Vol. IV, Page 32 

North East Two-Wire Starting and Lighting System Vol. IV, Page 30 

O 

Oakland 1914, Model 36— Wiring Diagram, Delco System.. . Vol. IV,. Plate 83 

Oakland 1914, Models 48-62— Circuit Diagram, Delco System Vol. IV, Plate 84 
Oakland 1914, Models 48-62-43— Circuit Diagram, Delco 

System Vol. IV, Plate 85 

Oakland 1914, Models 48-62-43— Wiring Diagram, Delco 

System Vol. IV, Plate 86 

Oakland 1915, Model 37— Circuit Diagram, Delco System.. . Vol. IV, Plate 87 

Oakland 1915, Model 49— Circuit Diagram, Delco System.. . Vol. IV, Plate 88 

Oakland 1917, Model 32-B— Delco System Vol. Ill, Page 373 



432 



INDEX 7 

Oakland, Model 34— Delco System Vol. Ill, Page 374 

Oakland, Model 32— Remy System Vol. IV, Page 63 

Oakland 1917, Model 34-B— Remy System Vol. IV, Page 64 

Oakland 1920, Model 34-C— Remy System Vol. IV, Plate 88A 

Oakland, Model 32— Remy System Vol. IV, Page 65 

Olds 6-Cylinder 1913, Model 53— Circuit Diagram, Delco 

System Vol. IV, Plate 89 

Olds 1914, Model 54r— Circuit Diagram, Delco System Vol. IV, Plate 90 

Olds 1915, Model 42— Circuit Diagram, Delco System Vol. IV, Plate 91 

Olds 1915, Model 55— Circuit Diagram, Delco System Vol. IV, Plate 92 

Olds 1917, Model 45— Delco System Vol. Ill, Page 377 

Olds 1917, Model 45A— Delco System Vol. Ill, Page 378 

Oldsmobile, Model 37— Remy System Vol. IV, Plate 93 

Oldsmobile 1919, Model 45-A— Delco System Vol. IV, Plate 93A 

Oldsmobile 1919, Model 45-B— Delco System Vol. IV, Plate 93B 

Oldsmobile 1920, Model 45-B— Delco System Vol. IV, Plate 93C 

Olympian 1917— Auto-Lite System Vol. IV, Plate 94 

Overland, Models 85 and 85-B— Auto-Lite System Vol. Ill, Page 275 

Overland Light Fours, Model 90-4— Auto-Lite System Vol. Ill, Page 276 

Overland— Auto-Lite System Vol. Ill, Page 278 

Overland Four, 1920— Auto-Lite System Vol. IV, Plate 94A 

P 

Packard 1915, Models 3-38 and 5-48— Bijur System Vol. IV, Plate 95 

Packard 1916 Twin Six— Bijur System Vol. IV, Plate 96 

Packard 6-Cylinder 1916— Bijur Two-Unit, Two- Wire System Vol. Ill, Page 204 

Packard 1919-20, Models 325, 335— Delco System Vol. IV, Plate 96A 

Packard 1920, Models 3-25, 3-35— Bijur System Vol. IV, Plate 96B 

Packard "Twin-Six," Models 2-35 and 2-25— Simplified 

Bijur System Vol. Ill, Page 306 

Packard "Twelves"— Bijur System Vol. Ill, Page 307 

Paige 1916-17, Model 639— Remy System Vol. IV, Page 57 

Paige, Model 6-55— Remy System Vol. IV, Page 58 

Paige-Detroit, Model 6-40— Remy System Vol. IV, Plate 97 

Pan, Model 250 — Circuit Diagram, Remy System Vol. IV, Plate 98 

Paterson 1914, Models 32-33— Delco System Vol. IV, Plate 99 

Paterson 1915, Models 4-32 and 6-48 — Circuit Eiagram, 

Delco System Vol. IV, Plate 100 

Paterson 1916, Model 6-42— Circuit Diagram, Eclco System Vol. IV, Plate 101 
Paterson 1917, Models 6-45 and 6-45-R — Circuit Diagram, 

Delco System Vol. IV, Plate 102 

Pathfinder 1917 12-Cylinder— Delco System Vol. Ill, Page 383 

Peerless, Model 56 — Chassis Wiring Eiagram for Gray & 

Davis Vol. Ill, Page 403 

Peerless, Model 56 — Electrical Diagram for Gray & Davis. . Vol. Ill, Page 404 

Peerless 1917— Auto-Lite System Vol. IV, Plate 103 

Pierce-Arrow, Series 4, Models 38, 48 and 66— Bosch System Vol. IV, Page 129 
Pierce-Arrow, Series 4 Enclosed Car, Models 38, 48 and 66— 

Westinghouse System Vol. IV, Page 130 



m 



8 INDEX 

Pierce-Arrow, Series 4, Models 38, 48, and 66 — Westinghouse 

System Vol. IV, Page 131 

Pierce-Arrow 1919-20, Models 38, 48— Delco System Vol. IV, Plate 103A 

Pilot 1917, Model 6-45— Delco System Vol. Ill, Page 384 

Premier 1914, Model M Generator — Remy System. . Vol. IV, Plate 104 

Premier 1915, Model M Generator— Remy System. . , Vol. IV, Plate 105 

Premier 1915, Model M J Generator— Remy System Vol. IV, Plate 106 

Premier 1917, Model 6-B— Delco System Vol. Ill, Page 389 

Premier 1919, Models 6-B, 6-C— Delco System Vol. IV, Plate 106A 

R 
Regal — Internal and External Wiring Diagram for Heinze- 

Springfield Vol. Ill, Page 421 

Regal 1917, Model J— Heinze-Springfield System Vol. IV, Plate 107 

Reo 1914-15— Remy System Vol. IV, Page 67 

"Reo the Fifth"— Remy System Vol. IV, Page 66 

Reo 1916— Remy System Vol. IV, Page 68 

Reo 4- and 6-Cylinder 1917— Remy System Vol. IV, Page 69 

Reo, Models T and U— Remy System Vol. IV, Plate 108 

Reo Model F 1500 Pound Truck— Remy System Vol. IV, Plate 109 

S 

Saxon 4-Cylinder 1916— Wagner System Vol. IV, Plate 110 

Saxon 1917, Model S-4— Remy System Vol. IV, Plate 111 

Saxon 4-Cylinder 1917 Roadsters, Models B-5-R and B-6-R 

—Wagner System Vol. IV, Page 109 

Saxon 6-Cylinder 1917, Models S-3-T, S-4-T and S-4-R— 

Wagner System * Vol. IV, Page 110 

Scripps-Booth — Bijur System Installed on Earlier Models. . Vol. Ill, Page 293 

Scripps-Booth — Bijur System Installed on Later Models .... Vol. Ill, Page 294 

Scripps-Booth 6-Cylinder— Remy System Vol. IV, Plate 112 

Scripps-Booth, Model G — Remy System Vol. IV, Page 70 

Scripps-Booth 4- and 6-Cylinder — Wagner Two-Unit System Vol. IV, Page 126 

Scripps-Booth 1920, Series B— Remy System Vol. IV, Plate 112A 

Simms-Huff — Wiring Diagram Vol. IV, Page 79 

Splitdorf-Apelco 12 m 6- Volt, Single-Unit, Two- Wire System 

Wiring Diagram Vol. IV, Page 88 

Splitdorf Lighting Generator and VR Regulator Wiring Dia- 
gram Vol. IV, Page 90 

Standard "8" 1917— Westinghouse System Vol. IV, Plate 113 

Stearns-Knight 4-Cylinder 1913— Gray & Davis System Vol. IV, Plate 114 

Stearns-Knight— Remy Single- Wire 12- Volt System Vol. IV, Plate 115 

Stearns, Model SKL 4— Remy System Vol. IV, Page 73 

Stearns 1916-17-18— Remy System Vol. IV, Page 74 

Stephens 1917— Delco System Vol. Ill, Page 390 

Stevens-Duryea 1915, Model D6 — Circuit Diagram, Delco 

System Vol. IV, Plate 116 

Stevens-Duryea 1915, Model D6 — Wiring Diagram, Delco 

System Vol. IV, Plate 117 



434 



INDEX 6 

Studebaker 1914-15 Grounded Battery— Remy System Vol. IV, Plate 118 

Studebaker 1914-15 Insulated Battery— Remy System Vol. IV, Plate 119 

Studebaker, Models SH, EH and EG— Remy System Vol. IV, Plate 120 

Studebaker 1916-17— Remy System Vol. IV, Page 75 

Studebaker 4 and 6, Models SF and ED — Remy Ignition and 

Wagner Systems Vol. IV, Page 123 

Stutz 1914-15— Circuit Diagram, Remy System Vol. IV, Plate 121 

Stutz 1916-17— Remy System Vol. IV, Page 76 

Stutz 1918, Series 3— Delco System. . . . .• Vol. IV, Plate 122 

Stutz, Model 1918— Delco System Vol. IV, Plate 123 

Sun Light Six, Model 17— Circuit Diagram, Remy System. . Vol. IV, Plate 124 

T 
Templar, Model 445 — Circuit Diagram, Remy System Vol. IV, Plate 125 

U 
U.S.L.— Wiring Diagram for 24-12-Volt External Regulator 

Type Vol. IV, Page 99 

U.S.L.— Wiring Diagram for 12-6^ Volt External Regulator 

Type Vol. IV, Page 100 

U.S.L. — Wiring Diagram for 24-12-Volt Inherently Regu- 
lated Type Vol. IV, Page 101 

V 

Velie, Model 22— Remy System Vol. IV, Page 59 

Velie 1916, Model 22— Remy System Vol. IV, Page 61 

Velie, Model 28— Remy System Vol. IV, Page 62 

Velie, Models 38, 39-7, 39 Sport — Circuit Diagram, Remy 

System Vol. IV, Plate 126 

W 

Wagner Twelve-Volt, Single-Unit, Two- Wire System — Wiring 

Diagram Vol. IV, Page 112 

Westcott 1915, Models U-6 and 0-35— Circuit Diagram, 

Delco System Vol. IV, Plate 127 

Westcott 1917-18— Delco System Vol. Ill, Page 350 

Westcott, Series 19— Delco System Vol. IV, Plate 128 

Westinghouse — Wiring Diagram for Generator with Self- 
Contained Regulator Vol. IV, Page 140 

Westinghouse — Wiring Diagram for System with External 

Regulator Vol. IV, Page 141 

Westinghouse — Diagram of Connections for Complete Sys- 
tem with Separately Mounted Regulator Vol. IV, Page 145 

White— Leece-Neville System Vol. IV, Page 15 

White, Model G-M— Leece-Neville System Vol. IV, Page 18 

Willys-Knight, Model 88-4— Auto-Lite System Vol. Ill, Page 281 

Willys-Knight, Model 88-8— Auto-Lite System Vol. Ill, Page 282 

Winton— Bijur System Vol. Ill, Page 288 

Winton Limousine Six, Model 22- A— Bijur System Vol. Ill, Page 305 

Winton Touring Six, Model 22-A— Bijur System Vol. Ill, Page 302 



436 ,Goo 9 Ie 



Digitized by VjOOQI 



Digitized by VjOOQIC 



GENERAL INDEX 



In this Index the Volume number appears in Roman numerals — thus, 
I, II, III, IV, etc., and the Page number in Arabic numerals — thus, 1, 2, 3, 4, 
etc. For example, Volume IV, Page 327, is written, IV, 327. 

The page numbers of this volume will be found at the bottom of the pages; 
the numbers at the top refer only to the section. 





Vol. 


Page 




Vol. 


Page 


A 






Air cooling (continued) 






Absorption of heat 


v, 


350 


flanges, or fins 


I, 


438 


Acetylene consumption, 






internal cooling and scav- 






measuring 


v, 


112 


enging 


I, 


439 


Acetylene generators 


v, 


15 


Air cushion 


II, 


214 


Acetylene regulator 


v, 


30 


Air and gasoline supply 






Acid, adding to storage bat- 






I, 242; VI, 


39, 40, 47 


tery 


IV, 


183 


auxiliary air valve 


I, 


243 


Addendum circle 


v, 


169 


double carburetors for 






Adjustable crankshaft flanges I, 


219 


multi-cylinder mo- 






Adlake automatic cut-out 


III, 


217 


tors 


I, 


247 


Advance and retard of spark 


III, 


59 


double-nozzle type 


I, 


245 


adjusting for time factor 






multiple-nozzle carburetors I, 


248 


of coil 


III, 


60 


nature of new develop- 






analysis of oscillograph 






ments 


I, 


246 


diagrams 


III, 


64 


use of by-pass 


I, 


246 


calculation of small time 






usual forms of auxiliary 






allowance 


III, 


60 


air-inlet valve 


I, 


243 


magneto timing 


III, 


62 


Venturi-tube mixing 






Mea method 


III, 


65 


chamber 


I, 


244 


Aeronautical motors 


I, 24, 81 


water-jacketing 


I, 


242 


Air I, 334 


;vi, 


51 


Air-inlet valve, auxiliary 


I, 


243 


need for cleaning 


VI, 


51 


Air jackets 


I, 


439 


pre-heating for carburetor 


I, 


334 


Air leaks in inlets-manifold 






Air cleaners, types of 


VI, 


53 


of motorcycle 


v, 


333 


air-washer type 


VI, 


53 


Air-supply system for pub- 






attention required 


VI, 


55 


lic garages 


v, 


254 


centrifugal type 


VI, 


53 


Air-washer 


VI, 


53 


felt baffle type 


VI, 


55 


Allen, firing order and igni- 






Air conditions in tractor 


VI, 


51 


tion advance 


III, 


77 


Air-cooled aviation motors 


I, 


86 


Alternating current, sources 






Air cooling 


I, 


438 


of 


VI, 


328 


air jackets 


I, 


439 


determining polarity 


VI, 


332 


blowers and fans 


I, 


439 


mercury arc rectifier 


VI, 


329 



NcU.—For page numbers »ee foot of vagee. 



437 



Digitized by 



Google 



INDEX 



Vol. Page 
Alternating current, sources 
of (continued) 

motor generator VI, 329 

Alternating-current rectifiers IV, 223 

Aluminum, cleaning I, 224 

Aluminum castings V, 81 

Aluminum welding V, 78 

Ammeter V, 317 
Ammeter readings in testing 

electrical system III, 265 

Amperage and voltage VI, 76 

Ampere-hour meter VI, 394 

Annealing V, 55 

Annular bearings, adjusting II, 81 

Anti-freezing solutions I, 437 
Apperson III, 77, 290, 300 

Arbor presses V, 173 

Arc welder V, 22 
Architectural appearance of 

public garage V, 239 
Armature of motor of elec- 
tric car VI, 294 
Armature testing III, 375 
Armature troubles VI, 388 
Armature windings II, 412 
Arrangement of oars in pub- 
lic garage V, 202 
Atwater Kent battery igni- 
tion system III, 102 
Atwater Kent interrupter III, 19 
Auburn, firing order and 

ignition advance III, 77 
Auburn-Delco electrical sys- 
tem, diagram for III, 254 
Austin, firing order and 

ignition advance III, 78 
Auto-Lite automatic en- 
gagement III, 229 
Auto-Lite system III, 266 
battery cut-out III, 274 
battery cut-out tests III, 283 
generator III, 266 
generator tests III, 280 
instructions III, 277 
instruments III, 277 
regulation III, 269 
starting motor III, 270 

Note. — For page numbers tee foot of pages. 



Vol. Page 



Auto-Lite system (contin- 






ued) 






wiring diagram 


III, 


277 


Auto-Ped motorcycle 


V, 


280 


Autocar delivery wagon 


VI, 


211 


Automatic battery cut-out 


III, 


216 


Automatic charge-stopping 






device 


VI, 


337 


Automatic engagement 


III, 


229 


Automatic gear-cutting ma- 






chine 


II, 


83 


Automatic switches III, 108; V, 


313 


Automatically timed sys- 






tems 


III, 


68 


Automobile boilers for 






steam cars 


v, 


380 


fire-tube boilers 


V, 


385 


flash boilers 


V, 


385 


special types 


v, 


387 


water-tube boilers 


V, 


382 


Automobile motors 


I, 18, 81 


vs. aviation motors 


I, 


81 


cylinders 


I, 


19 


valves 


I, 


19 


Automobile repair shops 


V, 11, 


123 


accurate filing in 


V, 


123 


welding in 


V, 


11 


Automobile repair by weld- 






ing, examples of 


V, 


97 


axle housings 


V, 


104 


bodies and fenders 


V, 


100 


crankcases and transmis- 






sion cases 


V, 


107 


engine cylinders 


V, 


105 


frames 


V, 


97 


manifolds 


V, 


104 


pressed-steel parts 


V, 


97 


shafts and axles 


V, 


103 


springs 


V, 


102 


Automobile and tractor 






VI, 11, 70, 121 


136 


Automobile welding, miscel- 






laneous processes 






in 


v, 


86 


carbon removing by use 






of oxygen 


v, 


95 


cutting 


v, 


86 



438 



Digitized by 



Google 



INDEX 



Automobile welding, miscel 
laneous processes 
in (continued) 
examples of automobile 

repair 
lead burning 
Auxiliary air valve 
Avery horizontal-opposed 

engine 
Aviation motors 
air-cooled 
B.R.I type 
Frederickson 
Jupiter 

Marlin-Rockwell 
Mercury 
Wasp 
aviation vs. automobile 

motors 
classification 
water-cooled 
Basse-Selve 
Curtiss V type 
Duesenberg 
Hall-Scott 
King-Bugatti 
Liberty V type 
Packard and Liberty 
Sunbeam-Coatalen fan 
type 
Axle bearings 
Axle housings, repair by 

welding 
Axle pivots, inclining 
Axles II, 151; 

B 



Vol. Page 



V, 97 
V, 91 
I, 243 

VI, 100 
1, 24, 81 
I, 86 
91 
86 
90 
88 
91 
89 



I, 
I, 

I, 
I, 
I, 
I, 

I, 
I, 
I, 
I, 

I, 
h 
I, 
I, 
I, 



81 
84 
91 
92 
96 
101 
95 
94 
99 
1, 101 

I, 104 
II, 161 

V, 104 
II, 106 
VI, 3B5 



B.R.I aviation motor I, 91 

B.t.u V, 354 

Babbitt, pouring V, 127 

Back-firing V, 34 

Back-kick release III, 232 

Balanced drive VI, 196 

Ball and Ball carburetor I, 281 

Ball bearings I, 478; II, 162 

Basse-Selve aviation motor I, 92 

Note. — Forlpage numbers see foo >oJ pages. 





Vol. 


Page 


Battery (see Storage bat- 






tery) 






Battery cut-out IV, 112, 121, 142 


!, 273 


Battery cut-out tests, Auto- 






Lite system 


Ill, 


283 


Battery equipment 


VI, 


198 


Battery ignition systems, 






modern 


III, 


99 


Atwater Kent 


III, 


102 


Connecticut 


III, 


105 


Delco 


III, 


111 


effect of starting and 






lighting develop- 






ments on ignition 


HI, 


99 


generator design follows 






magneto precedent III, 


99 


Remy 


m, 


108 


Westinghouse 


in, 


101 


Battery in starting and 






lighting systems, 







of 



outside 



IV, 
IV, 

IV, 
IV, 
IV, 
IV, 
IV, 
IV, 



summary 
structions 
buckled plates 
charging from 

source 
connectors 
Edison battery 
electrolyte 
gassing 

hydrometer tests 
intermittent and winter 

use 
joint hydrometer-volt- 
meter test 
low battery 
sediment 

specific gravity; voltage 
sulphating 
voltage tests 
washing battery 
Baum6 scale 
Bearing balls, saving 
Bearing scraping 
Bearing troubles and reme- 
dies 
Bearings 

I, 212, 468; II, 29, 126; VI, 



IV, 
IV, 
IV, 
IV, 
IV, 
IV, 
IV, 
VI, 
II, 

v, 



288 
300 

302 
299 
305 
288 
293 
291 



IV, 304 



292 
300 

297 
300 
294 
295 
298 
341 
77 
128 



I, 212 



144 



439 



Digitized by 



Google 



INDEX 



Vol. !Page 



Vol. Page 



Bearings (continued) 






ballbearings 


I, 


472 


bearing wear 


I, 


213 


combined radial and 






thrust bearing 


I, 


475 


crankshaft pounding 


I, 


214 


handy wrench 


I, 


216 


holding for bearing caps 


I, 


215 


plain bearings 


I, 


469 


roller bearings 


I, 


470 


test for tightness 


I, 


214 


types of bearings required 






for different loca- 






tions 


I, 


468 


Becker gear-cutting machine 


Hi 


84 


Bench methods in repair 






shop 


V, 


72 


Bench work 


V, 


115 


bearing scraping 


V, 


128 


chipping and filing 


V, 


117 


cutting gears 


V, 


168 


drilling 


V, 


144 


fitting piston rings 


V, 


135 


fitting taper pins 


V, 


155 


forging 


V, 


163 


hand keyseating 


V, 


156 


lapping cylinders 


V, 


141 


miscellaneous bench 






methods 


V, 


172 


reaming 


V, 


151 


rebabbitting bearings 


V, 


126 


riveting 


V, 


158 


soldering 


V, 


133 


tapping 


V, 


147 


use of micrometers 


V, 


139 


work bench design 


V, 


115 


Bendix drive 


III, 


425 


Bennett air washer 


I, 


321 


Bennett carburetor 


I, 


317 


Bent rod, straightening 


I, 


201 


Benzol 


I, 


110 


Bevel friction drive 


VI, 


119 


Bevel friction transmission 


II, 


62 


Bevel gears II, 88 


,114 


,261 


Bevel pinion and sector 






steering gear 


II, 


122 



Biddle, firing order and 






ignition advance 


III, 


78 


Bijur system 


HI, 


283 


generator 


III, 


283 


instructions 


in, 


293 


Apperson 


in, 


300 


Hupp 


in, 


299 


Jeffery 


in, 


296 


Packard 


in, 


304 


Scripps-Booth 


in, 


303 


Winton 


in, 


293 


instruments 


in, 


287 


regulation 


in, 


283 


starting motor 


in, 


287 


wiring diagrams 


in, 


287 


Apperson 


in, 


290 


Hupp 


in, 


290 


Jeffery 


in, 


28f 


Scripps-Booth 


in, 


290 


Winton 


in, 


287 


Bilgram gear-planing ma- 






chine 


ii, 


87 


Blacksmithing repair out- 






fit 


v, 


164 


Blowers 


i, 


439 


Blowouts 


ii, 


355 


Blowpipe V, 17, 26, 


33, 37, 89 


Blow torch, use of 


v, 


134 


Bodies and fenders, repair 






by welding 


v, 


100 


Boiler accessories and regu-» 






lation in steam 






cars 


v, 


388 


Boiler explosions, cause of 


v, 


357 


Boiler types in steam auto- 






mobile 


v, 


348 


Boosting 


VI, 


346 


advantages 


VI, 


346 


methods of boosting 


VI, 


348 


possible safe charging 






rates 


VI, 


347 


regulation of boosting 






charge 


VI, 


347 


Bosch ignition system 


m, 


48 


Bosch impulse starter 


VI, 


94 


Bosch incandescent lamp 


in, 


241 



Note. — For page number* see foot of pages. 



440 



Digitized by 



Google 



INDEX 



Vol. Page 
Boech-Rushmore automatic 

engagement III, 229 
Bosch-Rushmore generator III, 211 
Bosch-Rushmore system III, 308 
generator III, 308 
instructions III, 312 
instruments and protec- 
tive devices III, 310 
regulation III, 308 
starting motor III, 308 
wiring diagram III, 312 
Bour-Davis, firing order and 

ignition advance III, 78 

Boyle's law V, 352 

Brake adjustments II, 275 

Brake drums, truing II, 283 

Brake linings II, 282; V, 158 

Brake lubrication II, 275 
Brake operation, methods 

of II, 272 

Brake troubles and repairs II, 279 
Brakes 

II, 266; V, 305; VI, 203, 255, 324 

brake adjustments II, 275 

brake lubrication II, 275 

classification II, 267 
double-brake drum for 

safety II, 272 
electric brakes II, 275; VI, 324 
external-contracting brakes II, 267 
function of brake II, 266 
hydraulic brakes II, 276 
internal-expanding brakes II, 268 
methods of brake opera- 
tion II, 272 
motorcycle V, 305 
recent developments II, 275 
summary of instructions II, 361 
troubles and repairs II, 279 
vacuum brakes II, 277 
Brass welding V, 84 
Brazing malleable iron V, 78 
Brewster, firing order and 

ignition advance III, 78 
Briscoe, firing order and 

ignition advance III, 78 

British thermal unit V, 354 

Note. — For page numbers see foot of page*. 



Vol. Page 
Bronze welding V, 84 
Brown and Sharpe gear-cut- 
ting machine II, 83 
Brushes 

II, 420; IV, 255; V, 342; VI, 387 
Buckled battery plates, 
summary of in- 
structions IV, 300 
Buick III, 78, 338 
Buick-Delco electrical sys- 
tem, diagram for III, 250 
Building materials for pub- 
lic garages V, 237 
Built-in regulator type of 

generator III, 213 

Bunsen burner V, 375 

Burner principles V, 375 
Burners for steam cars V, 374, 409 

Bushing removers I, 192 

By-pass, use of I, 246 



Cable drives II, 62 
Cable in electrical equip- 
ment, calculating 

size of III, 95 
Cadillac III, 78, 335 

Cadillac carburetor I, 309 
Camber complicates axle 

ends II, 156 
Cams I, 370 
difficulties in making cams I, 382 
friction I, 370 
grinding increases accu- 
racy I, 383 
number of valves per 

cylinder I, 377 
old way required more 

accurate inspection I, 383 
one cam for two valves 

influences shape I, 380 
typical valve actions I, 374 
what good modern prac- 
tice shows I, 376 
Camshaft I, 402, 409 
chain drive for I, 402 
twisted I, 409 



441 



Digitized by 



Google 



6 



INDEX 



Vol. Page 

Camshaft and timing gear VI, 29 

Cantilever spring . II, 194 

Capacity of battery IV, 179 

Capacity of condensers II, 403 

Carbon burning V, 96 

Carbon deposits in cylinder I, 151, 167 

removal of I, 167 
compression indicating 

gage I, 172 

liquid solvent I, 169 
removing carbon by 

scraping tools I, 169 

Carbon-removing apparatus V, 96 
Carbon removing by use of 

oxygen V, 95 

Carbonizing flame V, 36 

Carburetor 

I, 151, 235; V, 327, 332; VI, 155, 220 

classification I, 237 

developments in I, 246 

effect of heavier fuels I, 235 

motorcycle V, 327, 332 

Carburetor adjustment, 

general I, 329 

starting at high speeds I, 329 

Carburetor and carburetion I, 235 
adjustment of air and 

gasoline supply I, 242 
inlet manifold design and 

construction I, 337 
kerosene and heavy fuel 

carburetors I, 313 

summary of instructions I, 354 

troubles and remedies I, 326 
Carburetor troubles and 

remedies I, 326 

Carburetor types I, 248 

Stromberg I, 248 

Zenith I, 252 

Holley I, 259 

Toquet I, 263 

Kingston I, 266 

Master I, 269 

Miller I, 271 

Webber I, 273 

Rayfield I, 277 

Note. — For page numbers see foot of pages. 



Vol. Page 
Carburetor types (continued) 

Ball and Ball I, 281 
Newcomb I, 284 
Marvel I. 288 
Schebler I, 291 
Stewart I, 294 
Johnson I, 297 
Carter I, 300 
H. &N. I, 303 
Tillotson I, 304 
Knox I, 305 
Sunder man I, 306 
Shakespeare I, 307 
Packard I, 308 
Cadillac I, 309 
Bennett I, 317 
Ensign I, 324 
Case, firing order and igni- 
tion advance III, 78 
Cast-aluminum welding V, 81 
Cast axles. II, 157 
Cast-iron welding V, 69 
oxidation V, 69 
preparation of welds V, 72 
welding rods V, 70 
Centrifugal air cleaner VI, 53 
Centrifugal governors VI, 107, 225 
auxiliary types VI, 109 
Chadwick, firing order and 

ignition advance III, 78 

Chain drive for camshafts I, 402 

Chain drive on electric car VI, 300 

Chain four-wheel drive II, 145 
Chalmers, firing order and 

ignition advance III, 78 
Chandler, firing order and 

ignition advance III, 79 

Charge, testing rate of IV, 231 

Charging current, sources of VI, 327 

alternating current VI, 328 

charging Edison battery VI, 345 

charging rate VI, 334 

direct current VI, 327 

electrolyte VI, 342 

starting charge VI, 336 

temperature of battery VI, 333 

voltage after charging VI, 332 



442 



Digitized by 



Google 



INDEX 



Vol. Page 
Charging rate of storage 

battery VI, 334 
Charging storage battery 

IV, 219; VI, 272, 327, 357 

boosting VI, 346 

sources of current VI, 327 

after washing VI, 357 

Chassis details of gasoline 

trucks VI, 254. 

Chassis group II, 168 

characteristics of parts II, 168 

frames II, 169 

shock absorbers II, 209 

springs II, 190 

summary of instructions II, 223 

Check valves V, 388 

Chemical sources of ignition 

current III, 16 
Chevrolet, firing order and 

ignition advance III, 79 
Chevrolet — Auto-Lite elec- 
trical system, dia- 
gram for III, 254 
Chicago, firing order and 

ignition advance III, 79 
Chipping in automobile re- 
pair V, 117, 156 
Chisel types used in repair 

work V, 118 

Circuit II, 377, 385, 407, 440; VI, 74 

multiple or shunt II, 387 

series II, 386 

series-multiple II, 387 

Circuit-breaker 

III, 218, 257, 367; IV, 272; VI, 201 
Circuit of high-tension mag- 
neto III, 36 
Circular pitch of gear 3 V, 169 
Circulation, water I, 431 
Cadillac system I, 434 
pumps I, 432 
thermosiphon I, 434 
Cleaning repair parts of 
electrical equip- 
ment IV, 239 
Cleaning storage battery 

IV, 201; VI, 353 

NoU. — For page numbers see foot of pages. 



Vol. Page 

Clearances in reamer teeth V, 153 

Clincher rims II, 316 
Clutch I, 36; II, 11; V, 308, 

339; VI, 113, 228 
motorcycle V, 308, 339 
types of II, 11 
Clutch to disengage starter 
from gasoline en- 
gine III, 230 
Clutch facings V, 159 
Clutch forms .in semi- 
three-quarter, and 
full-floating rear 
axles II, 246 
Clutch group II, 11 
details of clutch opera- 
tion II, 26 
• summary of instructions II, 94 
x types of clutches II, 11 
Clutch operation, details of II, 26 
Clutch troubles and reme- 
dies II, 30; VI, 177 
adjusting clutch pedals II, 38 
clutch spinning II, 35 
clutch troubles outside 

clutch II, 39 
cork inserts II, 35 
fierce clutch II, 34 
Ford clutch troubles II, 34 
handling clutch springs II, 33 
replacing clutch leathers II, 31 
slipping clutch II, 30 
summary II, 39 
Coal gas I, 108 
Coefficient of expansion V, 46 
Coey, firing order and igni- 
tion advance III, 79 
Coil III, 20, 174, 249 . 
Coil-spring shock absorber II, 211 
Cold-riveting metals V, 160 
Cole, firing order and igni- 
tion advance III, 79 
Commercial-car wheels II, 298 
Commercial vehicles 

II, 183; VI, 181-259 

classification VI, 183 

development of field VI, 181 



443 



Digitized by 



Google 



8 



INDEX 



Vol. Page 
Commercial vehicles (con- 
tinued) 

electric vehicles VI, 183 

frame construction II, 183 

gasoline vehicles VI, 211 

scope of VI, 181 

trailers VI, 257 

standard design VI, 182 

Commutators II, 409 
Commutator and brushes, 
summary of in* 

structions IV, 255 
Commutator maintenance 

in Delco system III, 372 
Compensating support, 

principles of VI, 255 

Compound distributor III, 45 

Compound expansion V, 364 

Compound-wound generator II, 418 

Compression I, 152; III, 125; V, 362 

effect of on indicator card V, 362 

effect of on spark III, 125 

poor I, 152 

Compression stroke I, 63, 67 

Condenser 

H, 403; III, 24, 30, 250; VI, 80 

Conduction V, 350 

Conductors II, 382, 390, 437; VI, 73 
Cone clutch II, 12; VI, 118, 228 

Connecticut battery system III, 105 

Connecting rod I, 197 
Connecting-rod bearings 

I, 199, 205; V, 129 
Connecting-rod troubles 

and repairs I, 201 
adjustment of connecting- 
rod bearings I, 205 
classification of troubles I, 201 
straightening bent rod I, 201 
Connections, importance of 

good III, 96 
Connectors of battery, sum- 
mary of instruc- 
tions IV, 299 
Constant-current generator III, 207 
Constant-potential gener- 
ator III, 212 

Note. — For page numbers tee foot of paoe*. 



Vol. Page 
Construction of motor car, 

general outline of I, 138 

Construction of motorcycles V, 293 

brakes V, 305 

clutches V, 308 

drive V, 306 

electrical equipment V, 311 
gearsets, or change-speed 

mechanisms V, 309 
lubrication V, 303 
motors V, 295 
regulation V, 315 
spring and frame con- 
struction V, 293 
starting V, 305 
Contact, symbol for III, 249 
Contact breaker III, 124; VI, 88 
Contact makers III, 19 
Contact points, summary 

of instructions IV, 276 

Contact timers III, 19 
Contracting-band clutch 

II, 14, 56; VI, 118 
Contraction in welding 

V, 18, 46, 47, 49, 56, 63, 70, 78 

Control in electric cars VI, 309 

controller VI, 310 

counter-e.m.f. VI, 309 

electric brake VI, 324 

fuses VI, 324 

methods of VI, 318 

ofl&ce of shunt VI, 322 

Control in gasoline tractors VI, 107 

clutches VI, 113 

engine governors VI, 107 

transmissions VI, 121 

Control in motorcycles V, 329 

Control in starting and 

lighting systems 

IV, 88, 111, 121, 135 
Control system lubrication 

in tractors VI, 143 

Controller in electric cars VI, 198, 310 

care of controller VI, 317 

drum type VI, 310 

duplex control VI, 317 

flat radial type VI, 312 



444 



Digitized by 



Google 



INDEX 



9 



Vol. Page 
Controller in electric cars 
(continued) 

flush types VI, 314 

magnetic type VI, 314 

Convection V, 350 

Cooling, internal I, 439 
Cooling circulation, types 

of VI, 67 
Cooling systems 

I, 36, 424; VI, 66, 159, 221 
air cooling I, 438 
in gasoline tractors VI, 66, 159 
in gasoline trucks VI, 221 
water cooling I, 424 
Cooling troubles and ad- 
justments I, 440 
Copper welding V, 82 
Cord tires II, 315 
Counter-e.m.f. II, 424; VI, 309 
Couple-Gear truck drive VI, 194 
Couple-Gear wheel II, 150 
Crank effort, theory of I, 41 
Crank and firing arrange- 
ments I, 36 
Crankcase I, 220; V, 107 
repair by welding V, 107 
Crankcase arms and engine 

supports I, 223 

Crankcase materials I, 223 

Crankcase oil I, 467 
Crankcase troubles and 

remedies • I, 224 
Crankshaft I, 208; V, 128 
holding upright on bench V, 128 
Crankshaft bearings I, 211 
Crankshaft and connecting- 
rod bearing shims I, 211 
Crankshaft lapping I, 219 
Crankshaft troubles and 

remedies I, 212 

Cross-connecting rods II, 138 

Crossed wires, symbol for III, 250 

Current II, 377, 392, 405; VI, 72 

Current and current control VI, 198 

battery equipment VI, 198 

brakes VI, 203 

controller VI, 198 

Note. — For page numbers see foot of paoc9. 



Vol. Page 
Current and current control 
(continued) 

safety devices VI, 201 

tires VI, 203 

Current direction III, 247 
Current supply in electrical 

equipment III, 123, 134 
Curtiss V type aviation 

motor I, 96 
Cut-off, operating on steam 

cars V, 409 
Cut-out switch connected 

to brake VI, 201 
Cut-outs I, 424; III, 362 
testing III, 362 
Cutting in automobile repair V, 86 
Cutting blowpipe V, 88 
Cutting gears in repair work V, 168 
Cutting with oxygen, prin- 
ciple of V, 87 
Cycle in explosion motors I, 13, 147 
four-stroke I, 14, 147 
six-stroke I, 17 
two-stroke I, 16, 147 
Cyclemotor V, 278 
Cylinder bore I, 176 
Cylinder and crankshaft 

sub-group I, 158 
connecting rods I, 197 
crankcases I, 220 
crankshafts I, 208 
cylinder forms and con- 
struction I, 158 
pistons and accessories I, 184 
Cylinder I, 19, 160, 164, 179; V, 144 
Cylinder forms and con- 
struction I, 158 
Cylinder heads I, 175 
Cylinder lapping, methods 

of I, 177 

Cylinder multiplication I, 148 

Cylinder oil, mixing with fuel I, 468 

Cylinder repairs I, 167 

D 

Dayton motorcycle V, 276 

Dead center, effect of I, 44 



445 



Digitized by 



Google 



10 



INDEX 



Vol. Page 

Dead center indicator I, 178 

Dedendum circle V, 169 
DeDion, firing order and 

ignition advance III, 79 

Defects in welds V, 42 

Delco ignition relay III, 115 

Delco ignition system III, 111 

adjusting Delco ignition 

relay III, 117 
Delco ignition relay III, 115 
earlier model interrupter III, 112 
interrupter for higher- 
speed engines III, 116 
timer with resistance unit III, 113 
Delco starting and lighting 

system III, 319 
instructions III, 352 
adjusting third brush III, 355 
commutator mainte- 
nance III, 372 
general instructions III, 352 
seating brushes III, 368 
testing armatures III, 375 
testing circuit-breaker III, 367 
testing cut-out III, 362 
testing field coils III, 382 
testing wiring III, 359 
six-volt; single-unit; sin- 
gle-wire III, 319 
control III, 320 
dynamotor III, 319 
protective devices III, 331 
regulation III, 324 
wiring diagrams III, 335 
six-volt; two-unit; single- 
wire III, 345 
generator III, 345 
regulation III, 346 
starting motor III, 346 
starting switch III, 349 
wiring diagram III, 349 
Delco third-brush excitation III, 210 
Delco wiring diagrams III, 335, 349 
Buick III, 338 
Cadillac III, 335 
Delivery wagon VI, 185, 211 
electric VI, 185 

Note. — For page numbers see foot of pages. 



Vol. Page 

Delivery wagon (continued) 

gasoline VI, 211 

Demountable rim II, 322, 333 

Demountable rim tire types II, 309 

Denatured alcohol I, 108 

Deppe" gas generator I, 322 

Deranged cells, detecting IV, 199 

Designs of public garages V, 207 

large size garage V, 218 

medium size garage V, 212 

small size garage V, 207 

very large garage V, 227 

Dies in repair work V, 150 

Differential lock VI, 245 

Differentials on rear axles, 

effect of II, 251 

Dimming devices ' III, 245 

Direct current, sources of VI, 327 

generators VI, 327 

service mains VI, 328 

Disc clutch II, 16 

Disc individual clutch II, 56 
Discharge of storage battery 

IV, 228; VI, 273, 279, 351 

limits of VI, 351 

rate VI, 279 

safe discharge point VI, 279 

testing rate of IV, 228 

Disco system III, 391 

six-volt; two-unit III, 391 

twelve-volt; single-unit III, 391 

Dismounting motor V, 128 

Distillates of petroleum 

I, 108; VI, 37 
Distilled water, adding to 

storage battery IV, 182 
Distributor III, 23, 51, 110, 172 
in Remy system III, 110 
summary III, 172 
Distributor leakage III, 125 
Dixie, firing order and igni- 
tion advance III, 80 
Dixie magneto III, 42 
Doble steam car V, 370, 397 
lubrication V, 398 
steaming test V, 398 



446 



Digitized by 



Google 



INDEX 



11 



Vol. Page 
Dodge, firing order and 

ignition advance III, 80 

Dog clutches VI, 231 
Dorris, firing order and 

ignition advance III, 80 
Dart, firing order and igni- 
tion advance III, 80 
Double-brake drum for 

safety II, 272 
Double carburetors for 

mulbi- cylinder 

motors I, 247 

Double-chain drive II, 238 

Double-nozzle carburetor I, 245 

Double-reduction live axle VI, 242 

Double-spark ignition III, 54 
Double-unit Westinghouse 

system IV, 139 

Drag link II, 134 

Drainage of public garages V, 250 

Draw filing V, 124 

Drill presses V, 180, 262 

Drilling hard metals V, 173 

Drilling in modern repair shop V, 144 

Drive, motorcycle V, 306 
Driving connections of 

starting motor III, 228 

Driving reaction II, 241 

Drop forgings for front axles II, 158 
Dropped rear axle of full 

floating type II, 245 

Drum type controller VI, 310 

Dry bearings VI, 386 

Dry cells, defects of III, 16 

Dual ignition system III, 48 

Duesenberg aviation motor I, 101 

Dummy brake drum useful II, 280 

Dunloptire II, 307 
Duplex control in electric 

car VI, 317 

Duplex ignition system III, 53 

Dynamo II, 408 
Dynamometer used to test 

horsepower I, 119 

Dynamotor II, 425; IV, 22, 77, 111, 135 
in starting and lighting 

systems IV, 22, 77, 111, 135 

Note. — For page numbers see foot of pages. 



Vol. Page 

Dyneto system III, 391 

six-volt; two-unit III, 392 

generator III, 392 

. instructions III, 397 

regulation III, 392 

starting motor III, 396 

wiring diagrams III, 396 

twelve-volt; single-unit; 

single-wire III, 391 

dynamotor III, 391 

instructions III, 392 

E 

Eagle horizontal engine VI, 100 

Early cut off, effect of V, 363 
Edison battery 

IV, 182, 305; VI, 288, 345 
advantages and disad- 
vantages VI, 290 
charging VI, 345 
composition of plates VI, 288 
size of battery VI, 291 
Eight-cylinder motor I, 43 
Eisemann centrifugal-gov- 
ernor automatic- 
ally timed system III, 69 
Eisemann impulse starter VI, 96 
Electric automobiles VI, 26 1-396 
care and operation VI, 327 
boosting VI, 346 
charging battery VI, 327 
cleaning battery VI, 353 
miscellaneous VI, 375 
putting battery out of 

commission VI, 373 

renewal of battery VI, 363 

fundamental features VI, 261 

control VI, 309 

motor VI, 292 

storage battery VI, 261 

transmission VI, 299 

indicating instruments VI, 394 

sources of power loss VI, 383 

tires and mileage VI, 389 

Electric brakes II, 275; VI, 324 

Electric car motor VI, 187, 292 

Electric car springs II, 201 



447 



Digitized by 



Google 



12 



INDEX 



Vol. Page 
Electric circuit II, 377, 440 
chemical effect of current II, 393 
circuits II, 385 
conductors II, 382 
current II, 377 
electrical pressure II, 378 
heating effect of current II, 392 
non-conductors II, 384 
Ohm's law II, 379 
power unit II, 380 
resistance II, 379 
short-circuit and grounds II, 389 
size of conductors II, 390 
voltage drop II, 383 
Electric delivery wagon VI, 185 
Electric drive II, 64, 65, 149 
Electric front drive VI, 246 
Electric or gas furnaces V, 164 
Electric gear-shift, sum- 
mary 6f instruc- 
tions IV, 286 
Electric generating clutch II, 24 
Electric horns III, 239 
Electric indicating instru- 
ments VI, 394 
Electric motor principles II, 421, 450 
batteries II, 427 
counter-e.m.f. II, 424 
dynamotors II, 425 
theory of operation II, 421 
types of motors II, 424 
Electric starting and light- 
ing systems 

III, 201; IV, 11-305 

general features III, 201 
practical analysis of types 

III, 247; IV, 11 
starting and lighting stor- 
age batteries IV, 173 
summary of instructions IV, 243 
Electric tractors VI, 203 
Electric transmissions 

II, 64, 65; VI, 251 

Electric trucks VI, 205, 207 

characteristics of chassis VI, 207 

classification VI, 207 

Electric vehicles VI, 183 

Note. — For page numbers see foot of pages. 



Vol. Page 
Electric vehicles (contin- 
ued) 
advantages VI, 184 
current and current con- 
trol VI, 198 
delivery wagon VI, 185 
motive power VI, 187 
power efficiency VI, 185 
range of use VI, 183 
special forms VI, 203 
trucks VI, 207 
Electric welding processes V, 21 
Electrical equipment for 
gasoline cars 
II, 375-453; III, 11-427; IV, 11 
cleaning IV, 239 
electric starting and light- 
ing systems III, 201 
elementary electrical 

principles II, 376 

ignition III, 11 

introduction II, 375 

practical analysis of types III, # 247 
testing, adjustment, and 

maintenance III, 122 

weakness of II, 375 
Electrical equipment of 

motorcycle V, 311 
Electrical equipment types, 

analysis of III, 247 
Auto-Lite system III, 266 
Bijur system III, 283 
Bosch-Rushmore system III, 308 
Delco system III, 319 
Disco system III, 391 
Dyneto system III, 391 
explanation of wiring dia- 
grams III, 247 
Gray & Davis system III, 398 
Heinze-Springfield sys- 
tem III, 420 
protective and testing 

devices III, 257 
Electrical pressure II, 378, 404 
Electrical principles 

II, 376, 428; VI, 72 

circuits II, 377; VI, 74 



44S 



Digitized by 



Google 



INDEX 



13 





Vol. 


Page 




Vol. 


Page 


Electrical principles (con- 






Engine bearings, care of 


v, 


408 


tinued) 






Engine cylinders, welding 


v, 


105 


conductors 


VI, 


73 


Engine group 


I, 


139 


electric current 


VI, 


72 


carburetion sub-group 


I, 


139 


electrical units 


VI, 


73 


cooling system 


I, 


141 


induction principles 


II, 


401 


cylinder and crankshaft 






low- and high-tension 






sub-group 


I, 


139 


currents 


VI, 


77 


exhaust system 


I, 


141 


magnetism 


II, 


394 


flywheel 


I, 


143 


voltage and amperage 


VI, 


76 


ignition system 


I, 


141 


Electrical symbols, signifi- 






inlet and exhaust valves 


I, 


141 


cance of 


III, 


247 


lighting system 


I, 


143 


Electrical troubles 


v, 


342 


lubrication system 


I, 


142 


Electrical units 


VI, 


73 


starting system 


I, 


142 


Electrically operated gears 


II, 


53 


Engine-group elements 


I, 


147 


Electrically operated 






Engine lubrication for 






switches 


III, 


236 


steam car 


v, 


404 


Electricity, importance of 






Engine of motorcycle 


v, 


295 


on automobiles 


II, 


375 


Engine operation in motor- 






Electrine 


I, 


110 


cycle 


v, 


289 


Electrode arrangement in 






Engine parts in tractors VI, I 


20, 24 


, 144 


spark plugs 


III, 


26 


details of operation 


VI, 


144 


Electrolyte 






engine bearings 


VI, 


144 


IV, 176, 288; VI, 263, 272 


,342 


pistons 


VI, 


152 


adjusting specific gravity 


VI, 


207 


valves 


VI, 


147 


determination of strength 






Engine repairs 


I, 


152 


of acid 


VI, 


264 


Engine in tractor 


VI, 


19 


precautions regarding 


VI, 


272 


Engine troubles I, 151 


;vi, 


163 


purity of acid and water 


VI, 


264 


in automobiles 


i, 


151 


replacing evaporation or 






in tractors 


VI, 


163 


other losses 


VI, 


266 


clutch and transmission VI, 


177 


temperature correction 


VI, 


264 


engine noises 


VI, 


176 


Electromagnets 


II, 


396 


failure to start 


VI, 


163 


Elements of Storage battery 






governor 


VI, 


177 


cell 


IV, 


175 


housing tractor 


VI, 


178 


Elevators vs. ramps for 






running troubles 


VI, 


172 


large size garage 


v, 


218 


Engine types V, 348, 360 


;vi, 


97 


Elkhart, firing order and 






in steam automobiles V, 34S, 


,363 


ignition advance 


III, 


80 


in tractors 


VI, 


C7 


Elliott front axle 


II, 


152 


Ensign fuel converter 


i, 


325 


Emery wheel 


v, 


262 


Ensign heavy fuel carbu- 






Empire, firing order and 






retors 


i, 


324 


ignition advance 


III, 


80 


Epicyclic, or planetary, gears II, 


59 


Enger, firing order and 






Equalizing charge of storage 






ignition advance 


III, 


80 


battery 


IV, 


221 


Engine I, 151, 193; 


;vi, 


163 


Erie, firing order and igni- 






failure to start I, 151: 


;vi, 


163 


tion advance 


in, 


81 



Note. — For page numbers see foot of pages. 



449 



Digitized by 



Google 



14 



INDEX 





Vol. 


Page 




Vol. 


Page 


European high-speed 






Field coils, testing 


Ill, 


382 


motorcycle engine 


V, 


301 


Field magnets 


II, 


414 


Exhaust gas friction 


I, 


73 


Filaments for incandescent 






Exhaust gases, importance 






lamps 


III, 


241 


of handling prop- 






Filing methods in automo- 






erly 


I, 


417 


bile repair 


v, 


119 


Exhaust manifolds, forms of 


I, 


418 


accurate filing 


V, 


123 


Exhaust stroke 


I, 64, 72 


cleaning files 


v, 


125 


Exhaust system 


I, 


417 


file shapes 


v, 


120 


Exhaust-valve setting 


I, 


387 


manipulation of files 


v, 


121 


Expanding-band clutch 


II, 


15 


presence of grease 


v, 


126 


Expanding-shoe clutch 


VI, 


117 


proper files for certain 






Expansion and contraction 






work 


v, 


120 


in welding 






types of files 


v, 


119 


V, 18, 46, 47, 49, 56, 


63, 70, 78 


uses of different shapes 






Explosion of charge 


I, 


69 


of files 


v, 


123 


Explosion motors 1,11-134 


;vi, 


35 


Filler cap 


I, 


337 


aviation motors 


I, 


81 


Final-drive group 






elementary principles 


I, 


11 


I, 144; II, 231; VI, 133 


,233 


first practical engine 


I, 


12 


brakes 


II, 


266 


fuels 


I, 


105 


rear axles 


II, 


231 


general description 


I, 


11 


summary of instructions 


II, 


361 


historical 


I, 


12 


tires 


II, 


307 


horsepower and rating 






wheels 


II, 


284 


calculations 


I, 


115 


Finances and building costs 






motor details 


I, 


25 


of public garages 


v, 


232 


summary of instructions 


I, 


127 


Financial problems of pub- 






thermodynamics 


I, 


53 


lic garage 


v, 


199 


types 


I, 


18 


Finish filing 


v, 


157 


Exterior design for public 






Fans 


I, 


438 


garage 


v, 


237 


Fire-tube boilers 


v, 


380 


Exterior lubrication ] 


[,443 


,456 


Firing arrangement 


I, 


36 


External-contracting brakes 


II, 


267 


four-cylinder motor 


I, 


40 


External regulator type of 






two-cylinder motor 


I, 


37 


generator 


m, 


214 


Firing order III, 73 
firing orders and ignition 


;vi, 


90 


F 






advance 


in, 


77 








magneto mounting 


in, 


97 


F.R.P., firing order and 






possible combinations 


in, 


75 


ignition advance 


HI, 


81 


typical orders 


in, 


73 


Failure to start engine I, 151 


;vi, 


163 


wiring 


in, 


92 


Fans I, 436, 439, 440; 


;vi, 


222 


Firing orders and ignition 






Fellows gear shaper 


ii, 


84 


advance 


in, 


77 


Felt baffle air washer 


VI, 


55 


Allen 


in, 


77 


Fergus frame 


ii, 


176 


Apperson 


in, 


77 


Fiat, firing order and igni- 






Auburn 


in, 


77 


tion advance 


in, 


81 


Austin 


in, 


78 



Note. — For page numbers see foot of pages. 



450 



Digitized by 



Google 



INDEX 



15 



Vol. Page 



Vol. Page 



Firing orders and ignition 






Firing orders and ignition 




advance (contin- 






advance (contin- 




ued) 






ued) 




Biddle 


III, 


78 


Marion-Handley I 


[I, 85 


Bour-Davis 


III, 


78 


Marmon I! 


[I, 85 


Brewster 


III, 


78 


Maxwell I 


[I, 86 


Briscoe 


HI, 


78 


Mercer I 


[I, 86 


Buick 


HI, 


78 . 


Militaire I! 


[I, 86 


Cadillac 


III, 


78 


Mitchell I] 


[I, 86 


Case 


HI, 


78 


Moline I 


[I, 86 


Chadwick 


HI, 


78 


Monroe I 


[I, 86 


Chalmers 


III, 


78 


Moon I 


[I, 86 


Chandler 


HI, 


79 


Murray I 


[I, 86 


Chevrolet 


HI, 


79 


National I 


[I, 86 


Chicago 


HI, 


79 


Oakland I 


[I, 87 


Coey 


III, 


79 


Oldsmobile I 


[1, 87 


Cole 


III, 


79 


Packard 1 


[I, 87 


De Dion 


III, 


79 


Paige-Detroit I 


[I, 87 


Dixie 


III, 


80 


Pathfinder I 


[I, 88 


Dodge 


III, 


80 


Patterson I 


[I, 88 


Dorris 


HI, 


80 


Peerless I! 


[I, 88 


Dort 


HI, 


80 


Pierce-Arrow I 


[I, 88 


Elkhart 


III, 


80 


Pilliod I] 


[I, 89 


Empire 


III, 


80 


Premier I 


LI, 89 


. Enger 


III, 


80 


Princess I. 


[I, 89 


Erie 


HI, 


81 


Pullman 11 


[I, 89 


F.R.P 


HI, 


81 


Regal 11 


[I, 89 


Fiat 


III, 


81 


Reo I! 


[I, 89 


Ford 


III, 


81 


Ross I 


[I, 90 


Franklin 


III, 


81 


Saxon I] 


[I, 90 


Glide 


III, 


81 


Scripps-Booth I] 


[I, 90 


Grant 


III, 


81 


Simplex I! 


[I, 90 


Hollier 


HI, 


81 


Singer 1. 


[I, 90 


Homer-Laughlin 


III, 


82 


Spaulding I] 


[I, 90 


Hudson 


HI, 


82 


Sphinx I-] 


[I, 90 


Hupp 


III, 


83 


Standard I. 


[I, 91 


Interstate 


III, 


83 


Stearns I 


[I, 91 


Jackson 


III, 


83 


Studebaker I 


I, 91 


Jeffery 


HI, 


83 


Stutz 11 


[1, 91 


King 


III, 


84 


Sun 11 


LI, 91 


Kisselkar 


III, 


84 


Thomas L 


[1, 91 


Kline 


HI, 


84 


Trumbull 11 


I, 91 


Lexington-Howard 


HI, 


84 


Velie 11 


[I, 92 


Liberty 


III, 


84 


Westcott I 


I, 92 


Locomobile 


III, 


84 


Willys-Overland I] 


[I, 92 


McFarlan 


HI, 


85 


Winton I 


[I, 92 


Madison 


III, 


85 


Firing-up 


V, 402 



Note. — For page numbers see foot of pages. 



451 



Digitized by 



Google 



16 



INDEX 



Vol. Page 



Fixed-spark ignition sys- 






tems 


III, 


CS 


►Flame, welding 


V, 


79 


Flanges 


I, 


438 


Flash boilers 


V, 


385 


Flat drills 


V, 


144 


Flat-plate recoil springs 


II, 


214 


Flat radial controller 


VI, 


312 


Flexible joints 


II, 


234 


Floating disc clutch 


II, 


22 


Floats 


I, 


241 


Flush type controller 


V, 


314 


Flux for welding 


V, 19, 71 


Flywheel characteristics 


I, 


475 


Flywheel markings 


I, 


384 


Flywheel sub-group 


I, 


475 


Folding steering wheels 


II, 


133 


Force-feed splash lubrica- 






tion 


VI, 


62 


Forced cooling circulation 


VI, 


68 


Ford, firing order and igni- 






tion advance 


III, 


81 


Ford axles, checking up 


II, 


265 


Ford cars I, 257 


;iv, 


152 


carburetors on 


i, 


257 


electrical systems for 


IV, 


152 


Ford clutch troubles 


ii, 


34 


Ford electrical system 


IV, 


152 


Ford ignition system, sum- 






mary 


in, 


183 


Ford magneto III, 54 


, 130 


Ford planetary gears 


ii, 


60 


Ford spring 


n, 


200 


Ford steering gear 


ii, 


125 


Forging 


V, 


163 


Forgings for front axles 


II, 


158 


Four-cycle motor 






I, 14, 25, 50, 147 


;vi, 


10 


Four-cycle motorcycle engine V, 


289 


Four-cycle principle 


VI, 


20 


compression stroke 


VI, 


21 


exhaust stroke 


VI, 


22 


intake stroke 


VI, 


20 


power stroke 


VI, 


22 


Four-cylinder motor 


I, 40, 42 


Four-cylinder motorcycle 






engine 


v, 


300 



Vol. Page 
Four-stroke cycle I, 14, 25, 50, 147 
Four-wheel drives VI, 248 
Jeffery "Quad" VI, 250 
Four-wheel driving, steer- 
ing, and braking II, 142 
Four-wheel trailers VI, 258 
Troy trailer VI, 258 
Frame II, 168, 169; V, 97 
classes of frames II, 170 
effect on springs II, 173 
general characteristics II, 169 
pressed-steel frames II, 172 
rigid frame II, 173 
sub-frames II, 173 
summary of instructions II, 223 
tendency in design II, 171 
troubles and repairs II, 185 
types II, 175 
welding V, 97 
Frame bracing methods II, 189 
Frame construction, motor- 
cycle V, 293 
Frame group I, 146 
Frame troubles and repairs II, 185 
Franklin, firing order and 

ignition advance III, 81 
Frederickson aviation motor I, 86 
Fresh-oil lubrication VI, 65 
Friction disc II, 61 
Friction drive VI, 119 
bevel friction drive VI, 119 
Frictional-plate shock ab- 
sorber II, 210 
Front axle II, 151 
axle bearings II, 161 
materials II, 157 
troubles and repairs II, 163 
types II, 151 
Front axle troubles and re- 
pairs II, 163 
Front drives VI, 246 
early development VI, 246 
electric front drive VI, 246 
Front stand attachment for 

motorcycle V, 325 

Front-wheel drive II, 140 

Fuel I, 105, 235; VI, 38 



Note. — For page numbers see foot of pages. 



452 



Digitized by 



Google 



INDEX 



17 



Vol. Page 



Fuel (continued) 






denatured alcohol 


I, 


108 


effect of heavier 


I, 


235 


explosibility 


I, 


114 


gas and gas generators 


I, 


113 


other fuels 


I, 


110 


petroleum products 


I, 


106 


vaporizing 


VI, 


38 


war-time fuel develop- 






ments 


I, 


111 


Fuel available 


VI, 


36 


products of distillation 


VI, 


37 


Fuel developments due to 






War 


I, 


111 


Fuel feeding 


I, 


346 


Fuel line 


I, 


353 


Fuel mixture 


I, 


114 


Fuel spray, methods of 


» 




handling 


I, 


242 


Fuel supply 


I, 


346 


Fuel supply system of 






tractors 


VI, 26, 35 


air and fuel balanced 


VI, 


47 


details of spraying process 


VI, 


41 


effect of increasing speed 


VI, 


42 


fuels available 


VI, 


36 


gasoline and kerosene car- 






buretor 


VI, 


49 


heating requirements 


VI, 


44 


need for cleaning air 


VI, 


51 


operating principle of in- 






ternal-combustion 






motor 


VI, 


35 


proportion of air to gas 


VI, 


40 


tractor air conditions 






very bad 


VI, 


51 


types of air cleaners 


VI, 


53 


vaporizing fuel 


VI, 


38 


Fuel system of steam car 


V, 


388 


Fuel system troubles and 






repairs 


I, 


353 


Fuels, heat values of 


V, 


354 


Fuels for public garages 


V, 


252 


Fuels for steam cars 


V, 


374 


gasoline and kerosene 


V, 


374 


Full-elliptic spring 


II, 


192 


Full floating axle II, 243 


, 248 



Vol. Page 
Fuses III, 237, 259; IV, 271; 

V,*318;VI, 324 

Fusible plug V, 404 

G 

Garage furniture V, 255 

Garage tools V, 260 
Garages, public V, 197-266 
Gas and air in carburetion 

VI, 39, 40, 47 

Gas furnaces V, 164 

Gas and gas generators I, 113 

Gases, laws of V, 352 
Gases used in oxy-acetylene 

process V, 13 

Gaskets, making I, 174 

Gasoline I, 106, 111, 337 
Gasoline automobiles 

I, 137-487; II, 11-373 

bearings I, 468 

carburetors and carburetion I, 235 

chassis group II, 168 

clutch group II, 11 

cooling systems I, 424 
cylinder and crankshaft 

sub-group I, 158 
engine-group elements I, 147 
final-drive group II, 231 
flywheel sub-group I, 475 
general outline of con- 
struction I, 138 
introductory I, 13^ 
lubrication system I, 443 
steering group II, 105 
summary of instructions I, 227, 478 
transmission group II, 40 
valves and their mechanism I, 365 
Gasoline delivery wagons VI, 211 
Autocar VI, 211 
classification limits VI, 211 
White VI, 215 
Gasoline as fuel for steam car V, 374 
Gasoline heating require- 
ments in carbure- 
tion VI, 44 
Gasoline and kerosene car- 
buretor VI, 49 



Note. — For page numbers see fool of pages. 



453 



Digitized by 



Google 



18 



INDEX 



Vol. Page 
Gasoline line I, 337, 353 
Gasoline pump V, 408 
Gasoline railway cars, trans- 
mission needs of II, 55 
Gasoline strainer I, 327 
Gasoline tank, filling I, 337 
Gasoline tractors VI, 11-179 
analysis of tractor mech- 
anisms VI, 19 
control system VI, 107 
motors VI, 19 
introduction VI, 11 
operation VI, 135 
Gasoline trucks VI, 216 
chassis and running gear 

details VI, 254 
motor details VI, 217 
power transmission de- 
tails VI, 228 
Gasoline vehicles I, 137; VI, 211 
automobiles I, 137 
delivery wagons VI; 211 
trucks VI, 216 
Gassing of storage battery 

IV, 191, 293; VI, 273 

Gear cases I, 223 

Gear control I, 409 
Gear-cutting machines, 

types of II, 81 

automatic II, 83 

Becker II, 184 

Bilgram II, 87 

Brown and Sharpe II, 83 

Fellows II, 84 

Gleason , II, 85 

Whiton II, 82 

Gear drive on electric car VI, 301 

Gear operation, noise in II, 69 

Gear pitch and faces II, 93 

Gear pullers II, 71; V, 176 

Gear reduction on electric 

car, usual VI, 299 

Gear shifting II, 52, 72 

pneumatic system II, 55 

poor II, 72 

Gear troubles II, 93 

Gears II, 81; V, 89 

Note. — For page numbers see foot of pages. 



Vol. Page 
Gears (continued) 

cutting V, 89 

definition of terms V, 168 

method of design V, 169 

types of gear-cutting 

machines II, 81 

types of gears in automo- 
bile II, 88 
Gearsets, motorcycle V, 309 
Generator III, 207, 212, 249; 

IV, 11, 47, 121, 139, 156, 171, 243 
Generator design follows 

magneto precedent III, 99 
Generator output, control of III, 207 
Generator principles II, 408, 444 

armature windings II, 412 

brushes II, 420 

classification II, 408 

commutators II, 409 

elementary dynamo II, 408 

field magnets II, 414 

Generator-starting n»" 4 '»r IV, 95, 159 
Generator tests III, 280, 414 

Gleason gear planer II, 85 

Glide, firing order and igni- 
tion advance III, 81 
Governing I, 53 
Governor VI, 107, 224 
Governor troubles in tractors VI, 177 
Grant, firing order and igni- 
tion advance III, 81 
Gravity feeding I, 455 
Gravity-return layout of 
tire repair equip- 
ment II, 347 
Gray & Davis special sys- 
tem for Ford cars IV, 158 
installation IV, 158 
instructions IV, 158, 169 
testing generator with 

ammeter IV, 171 

Gray & Davis system III, 398 

generator III, 398 

Gray & Davis service tests III, 413 
instructions III, 409 

instruments III, 399 

regulation III, 399 



454 



Digitized by 



Google 



INDEX 



19 



Vol. Page 
Grease cups I, 468 

Grease gun, mammoth I, 463 

Greases I, 460 

Grinders V, 177, 262 

Grinding drills in repair shop V, 146 
Grinding in lathe V, 264 

Grounded motor, Gray & 

Davis system III, 407 

Grounded switch, Gray & 

Davis system III, 409 

Grounds II, 389; III, 249, 258 



H 



H. & N. carburetor I, 303 

Hack saws, power V, 182, 262 

Hall-Scott aviation motor I, 95 

Hammering V, 56, 69 

Hand keyseating in repair 

shop 
Hand tools for public garages 
Hardening steel 
Haywood vulcanizer 
Headlight glare 
Heat efficiency of motors 
Heat transformation 
Heat treatment in automo- 
bile repair 
Heat value of fuels 
Heat and work 
Heating charge 
Heating for public garages 
Heating requirements in 
carburet ion 

gasoline 

kerosene 
Heavier fuels, effect of 
Heavy fuel carburetors 
Heavy sheet-steel welding 
Heavy soldering 
Heavy welding section 
Heinze-Springfield system 

generator 

instructions 

regulation 

starting motor 

wiring diagram 

Note. — For page numbers see foot of pages. 



V, 


156 


V, 


260 


V, 


166 


II, 


341 


III, 


244 


VI, 


66 


V, 


354 


V, 


165 


V, 


354 


V, 


349 


I, 


341 


V, 


249 


VI, 


44 


VI, 


44 


VI, 


45 


I, 


235 


I, 


313 


V, 


61 


V, 


134 


v, 


68 


III, 


420 


III, 


420 


III, 


424 


III, 


422 


III, 


420 


III, 


424 



Vol. Page 

Helical gears II, 89 

Herringbone gears II, 89 
Herz ball-governor auto- 
matically timed 

system IU, 70 

High pressure, effect of V, 363 
High-speed motors in 

motorcycles V, 272 
High-speed single motor VI, 298 
High-tension cables in elec- 
trical equipment III, 92 
High-tension ignition sys- 
tem III, 14, 133; VI, 79 
High-tension magneto 

III, 35; VI, 86 
High-tension magneto cir- 
cuit VI, 87 
Hindley worm gear II, 124 
Hoists and cranes I, 154 
Holley all-fuel carburetor I, 314 
Holley carburetors I, 257, 264, 313 
Holley kerosene carburetor I, 313 
Hollier, firing order and 

ignition advance III, 81 
Homer-Laughlin, firing 
order and ignition 

advance III, 82 

Horizontal engine VI, 99 

Eagle VI, 100 

horizontal-opposed Avery VI, 100 

Oil-Pull VI, 99 
Horsepower ratings 

I, 115; VI, 162, 218 
Hose for welding apparatus V, 31, 37 

Hot-riveting metals V, 160 

Hotchkiss drive II, 196 

Housing tractor VI, 178 
Hudson, firing order and 

ignition advance III, 82 
Hupp III, 83, 290, 299 
Hydraulic analogy in igni- 
tion system III, 29 
Hydraulic brakes II, 276 
Hydraulic clutches II, 24 
Hydraulic gear II, 63 
Hydraulic governor VI, 226 
Hydraulic suspensions II, 217 



455 



Digitized by 



Google 



20 



INDEX 



Vol. Page 
Hydrogen gas lead-burning 

outfit IV, 215 

Hydrometer 

IV, 183, 200, 237; VI, 2C8 
Hydrometer tests of bat- 
tery, summary of 
instructions IV, 231 



I-head cylinder forms I, 166 
Ignition I, 31, 51; III, 11 
chemical source of cur- 
rent III, 16 
fundamental ignition prin- 
ciples III, 11 
ignition systems III, 48, 99 
induction sources of cur- 
rent III, 32 
modern battery ignition 

systems III, 99 

sources of current III, 16 

spark timing III, 59 

summary of instructions III, 131 
testing, adjustment, and 

maintenance III, 122 
voltage and spark control 

devices III, 18 
Ignition advance (see Fir- 
ing orders and 

ignition advance) III, 77 

Ignition batteries, summary III, 180 

Ignition current, sources of III, 16 
Ignition failure, general 

causes of III, 191 
Ignition in Ford system IV, 156 
Ignition methods, changes in III, 18 
Ignition in motorcycle V, 327 
Ignition principles, funda- 
mental III, 11 
Ignition setting point III, 71 
Ignition switch in Remy 

system III, 110 
Ignition system 

III, 48, 99; VI, 26, 71, 220 

electrical principles VI, 72 

importance of VI, 71 

Note. — For page numbers see foot of pages. 



Vol. Page 
Ignition system (continued) 

types of ignition systems VI, 78 
Illuminating gas lead-burn- 
ing outfit IV, 213 
Impulse starter VI, 94 
Bosch VI, 95 
Eisemann VI, 96 
Incandescent lamps III, 241 
Independent controllers III, 211 
Indicated horsepower I, 115 
Indicating instruments VI, 394 
ampere-hour meter VI, 394 
volt-ammeter , VI, 394 
Indicator I, 53; IV, 12, 55, 77, 97, 282 
Indicator car^, effect of 

compression on V, 362 

Indicator diagrams . V, 362 

Individual clutch II, 55 
Individual pump p essure 

feeding I, 455 

Induction II, 401 

Induction coil III, 250; VI, 79 
Induction principles in gen- 
erators and motors 

II, 401, 435 

capacity of condensers II, 403 

circuits II, 407 
comparison of generator 

current to water flow .U, 403 

current and volume 1 1, 405 

electric motor principles Ii, 421 

friction and resistance II, 405 

generator principles II, 408 

induction II, 401 

power comparison II, 406 

pressure and voltage ii, 404 

self-induction II, 402 
Induction sources of ignition 

current III, 32 
Inductor-type magneto III, 39 
Industrial trucks VI, 205 
Inherently controlled gener- 
ator III, 209 
Initial charge of storage 

battery VI, 367 

Injector blowpipe V, 17 



456 



Digitized by 



Google 



INDEX 



21 



Vol. Page 

Inlet manifold design and 

construction I, 337 

Inlet valve, troubles with I, 400 

Inner tube, improvement in II, 315 

Inner tube repairs II, 351 

Installation of starting motor III, 225 

Instruments used in starting 
and lighting sys- 
tems IV, 12, 55, 77, 97, 282 

Interior lubrication I, 443 

Interlocking devices for gears II, 51 

Internal-combustion motor, 

principle of I, 11; VI, 35 

Internal -combustion vs. 

steam tractors VI, 19 

Internal cooling and scav- 
enging I, 439 

Internal damage IV, 198 

Internal dogs, individual 

clutch using II, 55 

Internal-expanding brakes II, 268 

Internal-external gear indi- 
vidual clutch II, 57 

Internal-gear drive for trucks II, 247 

Internal gear-driven axle VI, 242 

Interrupters III, 110, 112, 116, 170 

Interstate, firing order and 

ignition advance III, 83 

Ironclad Exide cell VI, 283 

improved connectors VI, 285 

negative plate VI, 284 

positive plate VI, 283 

separators VI, 284 



Vol. Page 

Joint hydrometer and volt- 
meter tests IV, 200, 237, 292 

Joints in sheet-aluminum 

welding V, 79 

Joy valve gear V, 368 

Jupiter aviation motor I, CO 

K 

Kerosene I, 108 

Kerosene carburetors I, 313 
Kerosene as fuel for steam 

cars V, 374 
Kerosene and gasoline car- 
buretor VI, 49 
Kerosene heating require- 
ments in carburetion VI, 45 
Keyseating, hand V, 156 
Keyway, laying out V, 156 
King, firing order and igni- 
tion advance III, 84 
King-Bugatti aviation motor I, 94 
Kingston carburetor I, 257, 266 
Kisselkar, firing order and 

ignition advance III, 84 
Kline, firing order and igni- 
tion advance III, 84 
Knight motor, timing I, 414 
Knight sleeve valves I, 410 
Knocking in engine . I, 151 
Knox "F" carburetor I, 305 
Knox tractor spr>£ II, 198 



Jacking-up troubles II, 256 

Jackson, firing order and 

ignition advance III, S3 

Janney-Williams hydraulic 

gear II, 63 

Jeffery III, 83, 287, 296 

Jeffery-Bijur electrical sys- 
tem, diagram for III, 257 

Jeflfery Quad II, 145; VI, 250 

Jigs V, 57, 126 

Johnson carburetor I, 297 

Note. — For page numbers see foot of pages. 



L-head cylinder forms 


I, 


164 


L-head motor, valves in 


VI, 


28 


Lamp voltages 


III, 


242 


Lamps, summary of instruc- 




tions 


IV, 


279 


Lapping cylinders 


v, 


141 


Lapping in piston ring 


v, 


136 


Large size garage 


v, 


218 


Latent heat 


v, 


356 


Lathe 


V, 183, 


261 


Lathe and accessories 


V, 261, 


264 


Lathe equipment for repair 




shops 


V, 


185 



457 



Digitized by 



Google 



22 



INDEX 



Vol. Page 

Lathe work, simple V, 186 

Lead burning IV, 21 1 ; V, 91 ; VI, 375 

apparatus V, 93 

Leece-Neville system IV, 11 

generator IV, 11 

instructions IV, 13 

instruments IV, 12 

regulation IV, 11 

starting motor IV, 12 

wiring diagram IV, 13 

Lemoine front axle II, 154 

Lexington-Howard, firing 

order and ignition 

advance III, 84 

Liberty, firing order and 

ignition advance III, 84 

Liberty V type aviation motor I, 99 

Light sheet-steel welding V, 56 

Light soldering V, 134 

Light-weight motorcycles V, 280 

Lighting III, 241; IV, 279 

Lighting batteries III, 242 

Lighting in Ford system IV, 156 

Lighting of public garage V, 246 

Lines of magnetic force II, 399 

Liquid batteries III, 17 

Live axle VI, 242 
Locomobile, firing order and 

ignition advance III, 84 

Locomobile spring II, 201 
Loose connections in Gray 

& Davis system III, 410 
Low battery IV, 300 
Low cells IV, 188 
Low-tension currents VI, 77 
Low-tension ignition VI, 78, 83 
spark coil VI, 78 
timing of VI, 83 
Low-tension ignition sys- 
tem III, 13, 131 
Low-tension magneto 

III, 33; VI, 82 
Lubricant, care of in cold 

weather I, 463 
Lubrication I, 35, 196, 443; II, 28, 
58, 80, 140, 206, 256, 275; V, 

147, 182, 303, 328; VI, 55, 139, 223 

Note. — For page numbers Bee foot of pages. 



Vol. Page 

Lubrication (continued) 
in gasoline automobiles I, 196, 443 
in gasoline tractors VI, 55, 139 

in motorcycles V, 303, 328 

M 

McFarlan, firing order and 

ignition advance III, 85 
Machine tools for public 

garages V, 261 
Machines and machine pro- 
cesses in repair 

work V, 173 
arbor presses and gear 

pullers V, 173 

drill presses V, 180 

grinders V, 177 

lathes V, 183 

miscellaneous equipment V, 193 

power hack saws V, 182 

shapers V, 190 

Mack transmission VI, 231 
Madison, firing order and 

ignition advance III, 85 
Magnet, weak III, 123 
Magnet recharger III, 128 
Magnetic attraction and re- 
pulsion, laws of II, 395 
Magnetic clutch II, 24 
Magnetic field II, 397 
Magnetic force, lines of II, 399 
Magnetic plugs III, 27 
Magnetic substances II, 396 
Magnetic type controller VI, 314 
Magnetism II, 394, 432 
electromagnets II, 396 
laws of magnetic attrac- 
tion and repulsion II, 395 
lines of magnetic force II, 399 
magnetic field II, 397 
magnetic substances II, 396 
natural and artificial mag- 
nets II, 394 
poles of magnet II, 395 
solenoids II, 399 
Magneto II, 414; III, 32, 126, 134; 

VI, 82, 86 



458 



Digitized by 



Google 



INDEX 



23 



Vol. Page 
Magneto (continued) 

breakdown of III, 126 
high-tension III, 35; VI, 86, 91 

inductor-type III, 39 

low-tension III, 33; VI, 82 

summary III, 134 

timing III, 41 
typical construction de- 
tails and current 

production III, 39 

working principle III, 32 

Magneto generators V, 313 

Magneto impulse starter VI, 94 

Magneto mounting III, 97 

Magneto speeds III, 67 

Magneto timing III, 62 
Maintenance of electrical 

equipment III, 122 
Make-and-break-circuit 

mechanisms VI, 80 

Malleable-iron welding V, 77 
Management and care of 

steam cars V, 400 

Mandrel for turning pins I, 193 

Manifold I, 337, 342; V, 104 

repair by welding V, 104 

Manly hydraulic gear II, 63 

Manograph I, 56 

Manograph cards I, 74 

Marine motors I, 22 
Marion-Handley, firing 
order and ignition 

advance III, 85 
Marlin-Rockwell aviation 

motor I, 88 
Marmon, firing order and 

ignition advance III, 85 

Marmon self-lubricating axle II, 155 

Marmon spring II, 197 

Marvel carburetor I, 288 

Master carburetor I, 269, 317 

Master vibrator III, 21 
Maxwell, firing order and 

ignition advance III, 86 

Mazda incandescent lamp III, 241 
Mea method of advancing 

spark III, 65 

NoU. — Fnr pao* numbert see foot of pages. 



Vol. Page 

Mechanical efficiency I, 116 
Mechanical elements of 

steam engine V, 359 
Mechanical equivalent of 

heat V, 355 
Medium size garage, typical 

arrangements for V, 212 

Melting point of metals V, 44 
Mercer, firing order and 

ignition advance HI, 86 

Mercury arc rectifier VI, 329 

Mercury aviation motor I, 91 

Merkel motorcycle V, 278 
Metal - to - metal dry -disc 

clutch II, 19 
Micrometer V, 139, 141 

Mileage of electric car VI, 389 
Militaire, firing order and 

ignition advance III, 86 

Miller racing carburetor I, 271 

Milling in lathe V, .264 

Milling machines V, 193 

Misfiring I, 151, 335; in, * 58 
Mitchell, firing order and 

ignition advance III, 86 

Modified splash lubrication VI, * 59 
Moline, firing order and 

ignition advance • III, 86 

Moline vertical tractor motor VI, 104 
Monroe, firing order and 

ignition advance III, 86 
Moon, firing order and igni- 
tion advance III, 86 
Motive power of electric 

vehicles I, 187 
motor suspension with 

chain drive VI, 187 
motor suspension with 

shaft drive VI, 188 
shaft and chain transmis- 
sion VI, .192 
type of motor VI, 187 
unit-wheel drives VI, 193 
worm-gear transmission VI, x 190 
Motor I, 151, 193; H, 421; 

V, 128; VI, 163 

failure to start I, 151; VI, 163 



Digitized by 



Google 



24 



INDEX 



Vol. Page 
Motor accessories of gaso- 
line trucks VI, 220 
Motor-car construction I, 138 
Motor details I, 25; VI, 217 
four-cycle type I, 25 
of gasoline trucks VI, 217 
accessories VI, 220 
design VI, 217 
motor governors VI, 224 
small stationary gas engine I, 48 
Motor in electric cars VI, 187, 292 
armature VI, 294 
capacity for overloads VI, 295 
chain drive VI, * 300 
essentials VI, 292, 296 
gear drive VI, 301 
motor speeds VI, 297 
principle of rotation VI, 292 
worm drive VI, 303 
Motor generator IV, 223; VI, 329 
Motor governor VI, 107, 117, 224 
Motor group in automobile I, 139 
Motor lubrication I, 35, 443; VI, 139 
of gasoline automobiles I, 443 
of gasoline tractors VI, 139 
Motor of motorcycle V, 289, 295, 325 
European high-speed type V, 301 
four-cylinder type V, 300 
operation suggestions V, 325 
single-cylinder type V, 295 
two-cylinder type V, 297 
Motor parts in tractors VI, 20, 24, 144 
Motor repairs in automobile I, 152 
Motor speeds VI, 297 
advantages of series- 
wound motor VI, 297 
high-speed single motor VI, 298 
types of motor windings VI, 297 
Motor suspension with chain 

drive VI, 187 
Motor suspension with shaft 

drive VI, 188 

Motor in tractors VI, 19, 163 

troubles VI, 163 

Motor troubles I, 151, VI, 163 

in automobile I, 151 

in tractor VI, 163 

Note. — For page number* tee foot of paee*. 



Vol. Page 
Motor types in tractors VI, 97 
horizontal engine VI, 99 
vertical motors VI, 103 
wide range VI, 97 
Motor windings III, 223 ; VI, 297 
Motorcycle I, 22; V, 269-342 
analysis of mechanisms V, 287 
construction details V, x 293 
evolution of V, 269 
history V, 271 
operation and repair of V, 325 
present trend of models V, 271 
special bodies and attach- 
ments V, 320 
standard specifications V, 269 
types of V, 274 
Motorcycle bodies and at- 
tachments, special V, 320 
Motorcycle chains, cleaning V, 340 
Motorcycle engine, princi- 
ples of operation Vj 289 
Motorcycle improvements V, 273 
Motorcycle mechanism 

nomenclature V, 287 
Motorcycle types, develop- 
ments in V, 282 
Muffler I, 422; V, 341 
Multi-vibrator, complica- 
tion of III, 21 
Multiple circuit II, 387 
Multiple cylinders, repair 

man's interest in I, 47 
Multiple-disc clutch 

II, 18, 39; VI, 228 

Multiple-nozzle carburetors I, 248 
Murray, firing order and 

ignition advance III, 86 



N 



I, 110 



Naphthalene 

National, firing order and 

ignition advance III, 86 
Needle valve I, 240, 337 

Needle valve stem, bent I, 327 

Neutral flame V, 35, 54 

Newcomb air-heated carbu- 
retor I, 287 



460 



Digitized by 



Google 



INDEX 



25 





Vol. 


Page 


Newcomb carburetor 


I, 


284 


Non-conductors 


II, 


384 


Non-leaking rings 


I, 


195 


Non-return layout of tire 






repair equipment 


II, 


347 


Non-skid treads 


II, 


309 


Non-vibrator coil 


HI, 


22 


North East system 


IV, 


22 


dynamotor 


IV, 


22 


instructions 


IV, 


26 


protective devices 


IV, 


22 


regulation 


IV, 


22 


switch tests 


IV, 


35 


wiring diagrams 


IV, 


24 


Nozzle, adjustment of 


I, 


330 



Oakland, firing order and 

ignition advance III, 87 
Ofeldt boiler system V, 399 
Ohm's law II, 397, 431 
Oil, ^necessity for discard- 
ing when used VI, 62 
Oil barrels I, 464 
Oil filtering outfit I, 466 
Oil pipes, bending I, 467 
Oil-Pull horizontal engine VI, 99 
Oil pumps V, 303 
Oil settling tanks I, 466 
Oil tank and outfit for test- 
ing bearings I, 464 
Oilless bearings I, 470 
Oils and greases I, 460 
characteristics of good oils I, 460 
principles of effective 

lubrication I, 461 

testing oils for acid, etc. I, 461 

Oils for public garages V, 252 
Oldsmobile, firing order and 

ignition advance III, 87 
One-cylinder motor I, 41 
Open circuits V, 342 
Operating cut-off and re- 
verse on steam cars V, 409 
Operating suggestions for 

motorcycles V, 325 

Note. — For page number* see foot of pages. 



Vol. Page 
Operation and care of weld- 
ing apparatus V, 26 
Operation and repair of 

motorcycles V, 325 
Oscillograph diagrams, 

analysis of III, 64 

Otto engine I, 12 

Otto four-stroke cycle I, 61, 65 

ideal I, 61 

in practice I, 65 

modifications for modern 

motors I, 73 

Outer shoe repairs II, 354 

Overhauling storage battery IV, 205 

Overhead welding V, 41 
Overloads, capacity of motor 

of electric car for IV, 295 
Oversize tires, use of II, 311 
Oxidation V, 78 
Oxidizing flame V, 36 
Oxy-acetylene blowpipe VI, 377 
Oxy-acetylene cutting V, 20, 86 
Oxy-acetylene flame, char- 1 
acterof V, 18, 34 
Oxy-acetylene process V, 13, 34 
advantages of V, 13 
character of flame V, 34 
expansion and contraction V, 18 
flux V, 19 
gases V, 13 
generators V, 15 
oxy-acetylene cutting V, 20 
oxy-acetylene flame V, 18 
preparation of work V, 18 
strength of weld V, 19 
welding blowpipes V, 17 
welding rod V, 18 
Oxy-acetylene welding prac- 
tice V, 11-112 
introduction V, 11 
miscellaneous processes V, 86 
technic of oxy-acetylene 

welding V, 24 

welding processes V, 11 

Oxy-acetylene welding technic V, 24 

general notes on welding V, 40 



461 



Digitized by 



Google 



26 



INDEX 



Vol. Page 
Oxy-acety lene welding tech- 
nic (continued) 
instructions for connect- 
ing apparatus V, 32 
operation and care of 

apparatus V, 26 

simple welding job V, 24 

welding for different metals V, 44 
Oxygen, cutting with V, 87 

Oxygen-adding devices I, 312 

Oxygen consumption, meas- 
uring V, 109 
Oxygen welding regulator V, 30 



Packard in, 87, 304 

Packard bevel adjustment II, 261 

Packard carburetor I, 308 

Packard and Liberty motors I, 101 
Paige-Detroit, firing order and 

ignition advance III, 87 

Parabolic reflector III, 243 

Parker pressed-steel wheels II, 297 

Parker rim-locking device II, 334 

Parrett air cleaner I, 322 

Parrett vertical motor VI, 104 
Passenger attachments for 

motorcycles V, 320 
Pathfinder, firing order and 

ignition advance III, 88 
Patterson, firing order and 

ignition advance III, 88 
Pedals, clutch II, 27, 38 

Peening V, 172 
Peerless, firing order and 

ignition advance III, 88 

Perlman rim patents II, 330 

Petroleum products I, 106 

coal gas I, 108 

gasoline I, 106 

kerosene I, 108 

miscellaneous distillates I, 108 

Pierce-Arrow, firing order 

and ignition ad- 
vance III, 88 
Pilliod, firing order and 

ignition advance III, 89 

Note.— For page numbere see foot of page: 



Vol. Page 

Pilot light for steam cars V, 376 
Piping and connections for 
fuel supply 

I, 46, 184; VI, 152 

in gasoline automobiles I, 184 

in gasoline tractors VI, 152 

power exerted against I, 46 

Piston and accessories I, 184 

Piston pins I, 188 

Piston and ring troubles and 

repairs I, 182, 189 

Piston rings I, 185; V, 135 

Pitch diameter of gear V, 169 

Pitch of gear V, 169 

Plain bearings I, 469 

Plain rim II, 316 

Planers V, 194 

Planetary gear II, 59; IV, 114 

Plate clutch VI, 116 

Platform spring II, 193 

Pleasure-car steering wheels II, 131 

Pleasure-car wheels II, 286 

Plug threads III, 28 

Pneumatic drive II, 64 
Pneumatic system of gear 

shifting II, 55 

Pneumatic tires II, 307; VI, 390 

Poles of magnet II, 395 
Poppet valve and valve 

parts, repairing I, 390 

Poppet-valve gears I, 370 

cams I, 370 
repairing poppet valves 

and valve parts I, 390 

valve timing I, 384 

Portable electric motor V, 265 

Power hack saws V, 182, 262 

Power loss in electric cars, 

sources of VI, 383 

armature troubles VI, 388 

brushes and commutator VI, 387 

dry bearings VI, 386 

miscellaneous VI, 389 

non-alignment of axles VI, 385 
non-alignment of steering 

wheels VI, 384 

worn chains and sprockets VI, 385 



462 



Digitized by 



Google 



INDEX 



27 



YoLPage 



Vol. Page 



Power provision for public 






Public garages (continued) 






garages 


v, 


251 


designs of 


v, 


207 


Power rating of motors 


I, 


124 


finances and building costs 


v, 


232 


Power stroke 


I, 64, 72 


location 


v, 


200 


Power transmission details 






necessary equipment 


v, 


246 


of gasoline trucks 


VI, 


228 


preliminary problems 


v, 


197 


clutch 


VI, 


228 


range of business 


v, 


197 


electric transmission 


VI, 


251 


typical exterior design 


v, 


237 


advantages 


VI, 


251 


Pullman, firing order and 






several systems 


VI, 


252 


ignition advance 


in, 


89 


final drive 


VI, 


233 


Pumps, adjusting 


i, 


441 


classification 


VI, 


234 


Push rods and guides 


i, 


404 


differential lock 


VI, 


245 








double-reduction live 






Q 






axle 


VI, 


242 


Q. D. rim 


n, 


316 


four-wheel drives 


VI, 


248 


Quenching 


v, 


56 


front drives 


VI, 


246 


Quick-detachable rim 


H, 


316 


internal gear-driven axle VI, 


242 


clincher forms 


H, 


321 


side-chain drive 


VI, 


234 


No. 2 


H, 


319 


worm drive 


VI, 


237 


type for straight sides 


H, 


322 


transmission 


VI, 


228 








Power unit 


II, 


380 


R 






Pre-compression 


I, 


79 








Pre-heating in welding 


v, 


50 


Radial and thrust bearings 


I. 


475 


Premier, firing order, and 






Radiation of heat 


v, 


350 


ignition advance 


in, 


89 


Radiator, protection of 




- 


Pressed-steel axles 


II, 


159 


from stresses * 


U 


69 


Pressed-steel frames II 


, 172, 


175 


Radiator construction in 






Pressed-steel parts of car, 




- 


gasoline trucks 


VI, 


221 


repair by welding 


v, 


97 


Radiator and piping 


I, 


427 


Pressure II 


, 378, 404 


modifications of cellular 






Pressure blowpipe 


v, 


17 


and tubular forms 


I, 


430 


Pressure-circulated lubrica- 






types of cells 


I, 


429 


tion 


VI, 


64 


types of tubes 


I, 


429 


Pressure feeding, individual 






Radius rod 


VI, 


236 


pump 


I, 


455 


Rating motors 






Pressure and temperature 






I, 115, 124; VI, 


162, 


218 


in explosion motor VI, 22 


{,55 


Rayfield carburetor 


I, 


277 


Primary batteries 


III, 


16 


Reamers, kinds of 


v, 


154 


Priming plugs 


III, 


28 


Reaming in shop 


v, 


151 


Princess, firing order and 






Rear axle 


II, 


231 


ignition advance 


in, 


89 


summary of instructions 


II, 


361 


Progressive gears 


ii, 


41 


transmission 


II, 


231 


Prony brake 


i, 


117 


troubles and repairs 


II, 


256 


Protective devices 






types of rear axles 


II, 


243 


III, 216, 257; IV, 22, 55, 97, 270 


Rear-axle housings 


II, 


251 


Public garages \ 


, 197-266 


Rear-axle lubrication 


II, 


256 


Note.— For page number§ see foot of paces. 














44 


•a Digitized by ' 


C^ooqI 



28 



INDEX 





Vol. Page 




Vol. 


Page 


Rear-axle troubles and repairs II, 


256 


Revolving filing 


v, 


125 


Rear-wheel bearings 


II, 


255 


Rigid frame 


II, 


173 


Rebabbitting, jig for 


v, 


126 


Rim-cut repair 


II, 


357 


Rebabbitting bearings 


v, 


126 


* Ring clutch 


II, 


15 


Reducing flame 


v, 


36 


Ring gear, installing new 


v, 


161 


Reflectors 


III, 


243 


Ring knock, tracing 


I, 


196 


Regal, firing order and igni- 






Riveting 


V, 


158 


tion advance 


III, 


89 


Roller bearings I, 470 


>;ii, 


162 


Regulation, methods of 


III, 


207 


Roller clutch 


III, 


232 


Regulation devices III 


, 170, 


225 


Roller contact timer 


III, 


19 


Regulation in electrical sys- 






Ross, firing order and igni- 






tem of motorcycles 


v, 


315 


tion advance 


III, 


90 


Regulation in starting and 






Rotating valves 


I, 


416 


lighting systems 






Rotation of motor of elec- 






IV, 11, 22, 47, 77, 88, 9C 


\, 111, 




tric car 


VI, 


292 


121, 135 


, 139 


Running gear details of gas- 






Regulators, summary of 






oline trucks 


VI, 


254 


instructions 


IV, 


250 


Running troubles in tractors 


VI, 


172 


Regulators for welding 






S 






apparatus 


V, 29, 89 






Relative conductivity 


V, 


350 


Safe edge file, use of 


v, 


123 


Reliner, use of 


II, 


360 


Safety devices on electric 






Remagnetizing 


III, 


127 


vehicles 


VI, 


201 


Removing carbon 


v, 


95 


charging circuit-breaker 


VI, 


202 


Remy battery-ignition sys- 






circuit-breaker and hand 






tem 


III, 


108 


switch 


VI, 


201 


detecting grounds 


III, 


109 


cut-out switch connected 






ignition switch 


III, 


110 


to brake 


VI, 


201 


interrupter and distributor III, 


110 


devices to prevent acci- 






Remy ignition system 


III, 


50 


dental starting or 






Remy starting and lighting 






tampering 


VI, 


202 


system 


IV, 


47 


Safety gap, sparking at 


III, 


126 


single unit 


IV, 


56 


Safety gap in magneto 


III, 


37 


two-unit 


IV, 


47 


Saxon, firing order and 






Reo, firing order and igni- 






ignition advance 


III, 


90 


tion advance 


III, 


90 


Scale prevention and remedies V, 


405 


Repair shop equipment V 


, 173, 


193 


Scavenging I, 66, 80, 


439 


Replacements 


I, 


440 


Schebler carburetors 


I, 


291 


Reserve tanks 


I, 


352 


Scripps-Booth III, 90 


, 290, 


303 


Resistance II, 379, 382, 405; 


III, 


249 


Sediment in storage battery 






Retard of spark 


III, 


59 


IV, 297; 


VI, 


353 


Retreading 


II, 


358 


Selective types of sliding 






Retreading vulcanizers 


II, 


346 


gears 


n, 41, 42 


Reverse, operating on steam 






Self-excited fields 


II, 


417 


cars 


v, 


409 


Self-induction 


II, 


402 


Reversed Elliott front axle 


II, 


152 


Semi-elliptic spring 






Reversibility 


I, 


80 


II, 191, 198; 


;vi, 


254 



Note. — For page numbers see foot of pages. 



464 



Digitized by 



Google 



INDEX 



29 



Vol. Page 
Semi-floating rear axle II, 243, 246 
Semi-reversible gear II, 127 
Separators of storage bat- 
tery cell IV, 176; VI, 281 
Series circuit II, 386 
Series generator II, 417 
Series-multiple circuit II, 387 
Series plugs III, 27 
Series-wound motor VI, 297 
Seven-eighths floating rear 

axle II, 243 

Shackles for springs II, 204 
Shaft and axle, repair by 

welding V, 103 
Shaft and chain transmission VI, 192 
Shaft drive II, 235 
Shaft and hole, degrees of fit V, 189 
Shakespeare carburetor I, 307 
Shaler vulcanizer II, 341 
Simpers V, 190 
Sheet- Aluminum welding V, 79 
Shock absorbers II, 169, 209 
Shop equipment, impor- 
tance of V, 115 
Shop information V, 115-194 
bench work V, 115 
importance of shop equip- 
ment V, 115 
machines and machine 

processes V, 173 

Short-circuits III, 122, 389; V, 342 

Shunt, office of VI, 322 

Shunt circuit II, 387 

Shunt-wound generator II, 418 

Side-chain drive VI, 234 

radius and torque rods VI, 236 

speed reduction VI, 237 

standard types VI, 235 

Side-wall vulcanizer II, 345 

Silent-chain drive II, 239 

Silent-chain transmission VI, 233 

Simms-Huff system IV, 77 

change of voltage IV, 79 

dynamotor IV, 77 

dynamotor connections IV, 78 

instructions IV, 82 

instruments IV, 77 

Note. — For page numbers see foot of pages. 



Vol. Page 
Simms-Huff system (contin- 
ued) 

regulation IV, 77 

starting switch IV, 81 

wiring diagram IV, 82 
Simplex, firing order and 

ignition advance III, 90 
Singer, firing order and igni- 
tion advance III, 90 
Single-cylinder motorcycle 

engine V, 295, 339 

Single-disc individual clutch II, 56 

Single-pump pressure feeding I, 446 
Single-unit electrical systems 

III, 202,283,319, 391; IV, 22, 

56, 77, 87, 95, 111, 135 
Single-wire electrical sys- 
tems 
III, 203, 250, 277, 312, 335, 
349, 405, 424; IV, 22, 47, 77, 

135, 139 

Six-cylinder motor I, 42 

Six-stroke cycle I, 17 

Six-volt systems II, 47 

Sixteen cylinders and more I, 45 

Sixteen-valve engine VI, 34 
Twin City Multiple-valve 

engine VI, 35 
Sixteen-volt system North 

East IV, 22 

Slide valve on steam car V, 360 

Sliding gears II, 41; VI, 299 

electrically operated gears II, 53 

general method of operation II, 41 

interlocking devices II, 51 

modern selective types II, 42 

pneumatic shifting system II, 55 

progressive types II, 41 

railway car needd II, 55 

selective types II, 41 

transmission location II, 45 

Sliding-sleeve valves I, 409 

Slip joints II, 233 

Slipping-clutch, regulation 

of generator by III, 208 

Small garages V, 207 

Smith Motor wheel V, 274 



465 



Digitized by 



Google 



30 



INDEX 



Vol. Page 

Soldering V, 133 

Solenoids II, 399 

Solid gasoline I, 111 

Solid tires VI, 391 

Spark,effect of compression on III, 1 25 

Spark control devices III, 18 

Spark coil VI, 78 

Spark gap VI, 81 

Spark lever II, 134 
Spark plugs 

III, 24, 125, 163; V, 319; VI, 91 
Spark timing III, 59 
automatically timed sys- 
tems III, 68 
Eisemann centrifugal- 
governor type III, 69 
firing order III, 73 
ignition setting point III, 71 
Sparking, effect of irregular III, 59 
Sparking at safety gap III, 126 
Spanieling, firing order and 

ignition advance III, 90 
Specific gravity 

IV, 177, 188, 197, 300; VI, 267 
Specific heat V, 46, 354 
Speed controller type of 

motor governor VI, 225 

Speed reduction in final drive VI, 237 
Sphinx, firing order and 

ignition 'advance III, 90 

Spindle troubles and repairs II, 167 

Spiral bevel gear II, 91 

Spiral gears II, 90 

Splash lubrication I, 456; VI, 58 

Spot-welder, electric V, 21 
Spraying process in carbure- 

tion VI, 38, 41 

Spring clips, repair for broken II, 262 
Spring construction of 

motorcycles V, 293 
Spring troubles and reme- 
dies II, 206; V, 102 
Spring wheels II, 301 
Springs II, 33, 169, 190; VI, 254 
adjusting spring hangers II, 204 
basis of classification II, 190 
cantilever II, 194 

Note. — For page numbers see foot of pages. 



Vol. Page 

Springs (continued) 

clutch U, 33 

full-elliptic II, 192 

Hotchkiss drive II, 196 

platform II, 193 

semi-elliptic II, 191; VI, 254 

shackles and spring horns II, 204 
spring construction and 

materials II, 206 
spring lubrication II, 205 
summary of instructions II, 226 
three-quarter elliptic II, 192 
troubles and remedies II, 206 
unconventional types II, 197 
varying methods of at- 
taching springs II, 202 

Spur gears II, 88, 114 

Spur type friction transmis- 
sion II, 61 

Standard, firing order and 

ignition advance III, 91 

Standard ignition systems III, 48 

Standard threads in tapping V, 147 

Stanley fuel, water, and 

steam systems V, 389 

Stanley steam car V, 369 

Starting and lighting stor- 
age batteries IV, 173 

Starting and lighting sys- 
tems in, 266; IV, 11 
Auto-Lite HI, 266 
Bijur HI, 283 
Bosch-Rushmore in, 308 
Delco in, 319 
Disco in, 391 
Dyneto HI, 391 
Gray & Davis HI, 398 
Heinze-Springfield III, 420 
Leece-Neville IV, 11 
North East IV, 22 
Remy IV, 47 
Simms-Huff IV, 77 
Splitdorf IV, 87 
U.S.L. - IV, 95 
Wagner IV, 111 
Westinghouse IV, 135 
Ford IV, 152 



466 



Digitized by 



Google 



INDEX 



31 



VoL Page 
Starting and lighting stor- 
age batteries (con- 
tinued) 
care of IV, 173, 182 

importance of IV, 17.3 

principles of construction IV, 174 
Starting motor 
. HI, 219; IV, 12, 55, 91, 121, 

146, 152, 157, 261 
Starting-motor faults in 
Gray & Davis sys- 
tem III, 410 
Starting-motor test chart 
for Gray & Davis 
system III, 418 
Starting in motorcycle V, 305 
Starting speeds, wide varia- 
tion in III, 222 
Starting switches III, 233; IV, 81, 163 
Stationary gas engine I, . 48 
four-cycle type I, 50 
two-cycle type I, 48 
Steam automobiles V, 345-411 
automobile boilers V, 380 
boiler accessories and reg- 
ulation V, 388 
characteristic features V, 346 
engine types and details V, 369 
fuels and burners V, 374 
heat and work V, 349 
introduction V, 345 
management and care of 

steam cars V, 400 

mechanical elements of 

steam engine V, 359 

Steam engines, develop- 
ment of V, 345 
Steam vs. internal- 
combustion tractors VI, 19 
Stearns, firing order and ^ 

ignition advance III, 91 

Steel, hardening tempering V, 165 

Steel welding V, 53 

general considerations V, 53 

heavy, sheet-steel welding V, 61 

light sheet-steel welding V, 56 

Note.— For page number* see foot of pages. 



VoL Page 
Steel welding (continued) 
welding heavy steel f org- 
ings and steel cast- 
ings V, 67 
Steering gear I, 468 
Steering-gear troubles and v 

repairs II, 129 

Steering gears II, 105 

action of wheels in turning II, 107 

Ford steering gear II, 125 

general characteristics of - ^ 

steering gears II, 110 

general requirements II, 105 

inclining axle pivots II, 106 

removing II, 128 

semi-reversible II, 127 

spur and bevel II, 114 

steering levers in front of < 

axle H, 108 

troubles and remedies II, 129 

worm-gear II, 115 

Steering group I, 145; II, 105 

front axles II, 151 

gears II, 105 

rod, or drag link II, 134 

special types of drive II, 140 

summary of instructions II, 218 

wheels II, 130 

Steering knuckles II, 139 

Steering levers in fr6nt of ' 

axle II, 108 

Steering rod II, 134 

Steering wheels II, 130; VI, 384 

Stephenson link valve gear V, 367 

Stewart carburetor I, 294 

Storage of batteries VI, 373 

Storage battery 111,117; * - - 

IV, 173; V, 318, 342; VI„ 261 
construction and action 

of typical cell VI, 262 

types of cells VI, 281 

Storage battery care VI, 351 

cleaning battery VI, 353 

importance of careful * 

attention VI, 351 

limits of discharge VI, 351 

miscellaneous VI, 375 



467 



Digitized by 



Google 



32 



INDEX 





Vol. 


Page 




Vol. 


Page 


Storage battery care (con- 






Sunbeam-coatalen fan type 






tinued) 






aviation motor 


I, 


104 


putting battery out of 






Sunderman "Nitro" carbu- 






commission 


VI, 


373 


retor 


I, 


306 


. renewal of battery 


VI, 


363 


Superheated steam 


v, 


364 


sulphating 


VI, 


351 


Superheating 


v, 


358 


Storage battery cells 






Switch tests for North East 






IV, 175, 177 


;vi, 


281 


system 


IV, 


35 


Edison battery 


VI, 


288 


Switches, summary III, 173 


;iv, 


278 


general characteristics 


VI, 


281 


Switches in starting and 






improvements 


VI, 


282 


lighting systems 


in, 


233 


Ironclad Exide type 


VI, 


283 


Symbols, significance of 


in, 


247 


starting batteries 


VI, 


286 








Storage battery construc- 






T 






tion and action 


VI, 


262 








capacity VI 


, 278, 


, 279 


T-head cylinder forms 


i, 


164 


charge 


VI, 


272 


Tables 






discharge 


VI, 


273 


American wire gage(B.& S.) II, 


391 


efficiency 


VI, 


274 


average resistance of soils 


vi> 


19 


electrolyte 


VI, 


263 


Baume scale of specific 






general description 


VI, 


262 


gravities 


VI, 


341 


hydrometer 


VI, 


268 


boosting rates 


VI, 


350 


rate of discharge 


VI, 


279 


carrying capacity of wires 


ii, 


394 


restoring sulphated battery VI, 


276 


characteristics of North 






safe discharge point 


VI, 


279 


East starting and 






sulphating 


VI, 


274 


lighting apparatus 


IV, 


, 36 


Storage battery in Gray & 






charging voltage for lead 






Davis system for 






batteries 


VI, 


333 


Ford cars \ 


IV, 


164 


effects of clearance 


i, 


69 


Storage battery instructions 


VI, 


381 


explosion motor fuels 


i, 


107 


Storage battery jar, replacing 


IV, 


202 


potential boosts at differ- 






Stromberg carburetors 


I, 


248 


ent states of dis- 






Stromberg Ford carburetor 


I, 


261 


charge 


VI, 


348 


Studebaker, firing order and 






Royal Automobile Club's 






ignition advance 


III, 


91 


committee report 






Stutz, firing order and igni- 






on Knight engine 


I, 


412 


tion advance 


III, 


91 


sulphuric-acid solutions 


VI, 


265 


Sub-frames 


II, 


173 


temperature correction 






Suction pressure 


I, 


67 


for specific gravity 






Suction stroke 


I, 61 


L, 65 


of electrolyte 


VI, 


339 


Sulphate tests of storage 






test chart for Gray & 






battery 


VI, 


276 


Davis generators 


III, 


415 


Sulphating of storage bat- 






test chart for Gray & 






tery 






Davis starting 






IV, 194, 294; VI, 


, 274, 


351 


motor 


III, 


417 


Sun, firing order and igni- 






timing regulation of 






tion advance 


III, 


91 


American motors 


I, 


372 


Note. — For page numbers see foot o 


/ paget 


r. 












468 


| Digitized by VjOOQ IC 



INDEX 



33 





Vol. 


Page 




Vol. 


Page 


Tables (continued) 






Third brush, adjusting 


HI, 


355 


timing regulation of 






Thomas, firing order and 






French motors 


I, 


371 


ignition advance 


HI, 


91 


Tank placing 


I, 


346 


Threads, standard 


v, 


147 


Taper pins, fitting 


V, 


155 


Three-quarter elliptic spring 


II, 


192 


Tappet, noisy 


I, 


390 


Three-quarter floating axle 






Tapping in repair shop work 


v, 


147 


II, 243 


, 246 : 


, 250 


Taps used in repair shop 


v, 


148 


Throttle lever 


II, 


134 


Temperature corrections in 






Throttle loose on shaft 


I, 


328 


adjusting specific 






Throttle valves 


I, 


239 


gravity IV, 19C 


); VI, 


264 


Throttling 


I, 


80 


Temperature and pressure 






Thrust and radial bearing 


I, 


475 


in explosion motor VI, 22, 55 


Tie rods 


II, 


138 


Temperature scales 


v, 


351 


Tillotson carburetor 


I, 


304 


Tempering steel 


V, 


165 


Timer, summary III 


, 170, 


, 184 


Test set 


III, 


260 


Timer with resistance unit 






Testing I, 195, 461; III 


, 122, 




used with Delco 






280, 359, 375, 414; IV, 


, 228, 


231 


system 


III, 


113 


armatures 


III, 


375 


Timing gear 


VI, 


29 


battery cut-out 


III, 


283 


Timing valves 


VI, 


31 


circuit-breaker 


III, 


367 


Tire construction 


II, 


335 


contact breaker 


HI, 


124 


Tire improvements, recent 


II, 


314 


current supply 


HI, 


124 


Tire inflation pressures, 






cut-out 


III, 


362 


proper 


II, 


310 


field coils 


HI, 


382 


Tire repair equipment 


II, 


339 


generator III 


:,280, 


,414 


Tire repairs 


II, 


339 


oils for acid 


I, 


461 


inner tube repairs 


II, 


351 


size of new piston 


I, 


195 


outer-shoe, or casing, re- 






storage battery IV, 


, 228, 


231 


pairs 


II, 


354 


wiring III, 


, 123, 


359 


repair equipment 


II, 


339 


Testing devices III, 


257, 


263 


Tire rims 


II, 


316 


Thermal conductivity 


v, 


44 


Tire valves II 


, ?14, 


337 


Thermal efficiency 


I, 


64 


Tires II, 307; V, 329; 


VI, 


203 


Thermodynamics of explo- 






changing 


II, 


312 


sion motor 


I, 


53 


kinds 


II, 


307 


indicators 


I, 


53 


motorcycle 


v, 


329 


manograph 


I, 


56 


pneumatic 


II, 


307 


Otto four-stroke cycle, 






rims 


II, 


316 


ideal 


I, 


61 


summary of instructions 


II, 


361 


Otto four-stroke cycle, in 






construction 


II, 


335 


practice 


I, 


65 


repairs 


II, 


339 


two-cycle motor diagram 


I, 


78 


Tires and mileage 


VI, 


389 


Thermodynamics of steam 


v, 


356 


improper inflation 


VI, 


393 


Thermostatic switch in 






kinds of tires 


VI, 


390 


Remy regulation 


IV, 


48 


new tire equipment 


VI, 


392 


Thermosiphon circulation 






relation of 


VI, 


389 


I, 434; 


VI, 


68 


test curves 


VI, 


391 


Note. — For page numbers see foot of paget 


!. 












4 


go Digitized by 


GooqI 



34 



INDEX 



Vol. Page 

Tires and rims, standard sizes II, 331 
Tool equipment for larger 

public garages V, 265 

Toquet Ford atomizer I, 261 

Torque bar II, 239 

Torque rod VI, 236 

Tracklayer vertical motor VI, 103 
Tractor (see gasoline tractor) 

VI, 11, 203 

electric VI, 203 
Tractor air conditions very 

bad VI, 51 
Tractor and automobile 

VI, 11, 70, 121, 136 

Tractor classes VI, 12 
development of tractor 

industry VI, 12 

lack of standardization VI, 12 

types of tractors VI, 13 

Tractor clutches VI, 113 

functions VI, 113 

friction drive VI, 119 

types VI, 114 

Tractor fuel supply system VI, 26, 35 

Tractor ignition system VI, 26, 71 

Tractor industry VI, 12 

Tractor lubrication VI, 139 

control system VI, 143 

motor VI, 139 

Tractor mechanisms VI, 19 

control system VI, 107 

motors VI, 19 

Tractor motor troubles VI, 163 

Tractor motors VI, 19 

cooling system VI, 66 

fuel supply system VI, 35 

ignition system VI, 71 

lubricating system VI, 55 

types of motors VI, 97 

valves and valve timing VI, 28 

Tractor operation VI, 135 

carburetor VI, 155 

cooling system VI, 159 

engine parts VI, 144 

engine troubles VI, 163 

general instructions VI, 135 

horsepower ratings VI, 162 

Note. — For poo* number* «ee foot of page*. 



Vol. Page 
Tractor operation (contin- 
ued) 

lubrication VI, 139 
Tractor parts giving most 

trouble VI, 136 
spares necessary VI, 137 
Tractor selection VI, 14 
financial return VI, 14 
size of farm VI, 15 
size of tractor VI, 16 
work done on demonstra- 
tion no criterion VI, 14 
Tractor size VI, 16 
factors governing capacity VI, 18 
margin of safety VI, 17 
power for belt work VI, 17 
Tractor transmissions VI, 121 
final drive VI, 133 
function VI, 122 
heavy types VI, 126 
intermediate types VI, 127 
range of types VI, 122 
special types VI, 129 
speed vs. weight VI, 121 
speeds VI, 123 
Tractor types VI, 13 
Trailers VI, 257 
four-wheel types VI, 258 
two-wheel types VI, 257 
utilizing excess power VI, 257 
Transformer III, 31 
Transformer principle II, 401 
Transmission I, 143; II, 40, 231; 

VI, 121, 177, 228, 299 

electric cars VI, 299 
gasoline automobiles 

I, 143; II, 40, 231 

gasoline tractors VI, 121, 177 

troubles VI, 177 

gasoline trucks VI, 228 

classification II, 40 

freak drives II, 62 

friction disc II, 61 

gears II, 81 

individual clutch II, 55 

miscellaneous types II, 62 

planetary gears II, 59 



470 



Digitized by 



Google 



INDEX 



35 





Vol. 


Page 




Vol. 


Page 


Transmission (continued^ 






Two-wire electrical system 






gasoline trucks 






III, 203, 254; IV, 1 1, 22, 87, 95, 1 11 


sliding gears 


n, 


41 


Two-unit electrical systems 






summary of instructions 


i ii, 


99 


III, 202, 266, 283, 308, 345, 




.troubles and repairs 


ii, 


69 


391, 392, 398, 420; IV, 


11,47 


,121 


Transmission adjustments 


ii, 


59 








Transmission bearings 


ii, 


59 


U 






Transmission rare, repair by 












' welding 


v, 


107 


U. S. Nelson system 


IV, 


111 


Transmission. )nratinn 


II, _. 


45 


U. S. L. system " 

generator-starting motor 


IV, 


95 


Transmission lubrication 


II, 58, 80 


IV, 


95 


Transmission operation 


II, 


58 


instructions 


IV, 


98 


Transmission and regula- 






instruments and protec- 






tion devices 


III, 


225 


tive devices 


IV, 


97 


Transmission troubles and 






Nelson system 


IV, 


111 


% repairs 


II, 


69 


regulation 


IV, 


96 


Troy trailer 


VI, 


258 


twelve-volt system 


IV, 


107 


Truck VI, 205 


, 207, 


216 


fuse blocks 


IV, 


107 


electric VI, 


, 205, 


207 


starting switch 


IV, 


107 


gasoline 


VI, 


216 


variations 


IV, 


95 


Truck types of steering wheels II, 


131 


wiring diagrams 


IV, 


98 


Trumbull, firing order and 






Underpans, steel 


II, 


181 


ignition advance 


HI, 


91 


Underslinging springs 


II, 


203 


Truss rods 


II, 


259 


<r Unisparker," operation of 


III, 


103 


Tubular axles 


II, 


159 


Unit-wheel drives 


VI, 


193 


drop-forged ends 


II, 


159 


balanced drive 


VI, 


196 


Tungsten filament for in- 






couple-gear truck drive 


VI, 


194 


candescent lamps 


HI, 


241 


Universal-joint housings 


II, 


258 


Twelve-cylinder motor 


I, 


44 


Universal joints 


II, 


232 


Twelve six-volt systems IV, 87 


f , 95 








Twelve-volt systems 






V 






IV, 22, 77 


, HI, 


135 


Vacuum brakes 


II, 


277 


Twenty-four twelve-volt 






Vacuum machinery, use of 






system, U.S.L. 


IV, 


95 


in public garage 


v, 


228 


Twenty-four volt system 


IV, 


22 


Valve I, 19, 25, 365, 374, 390 s 


,395 


Twin City multiple-valve 






action of 


I, 


374 


engine 


VI, 


35 


adjusting tension 


I, 


395 


Twin-cylinder motorcycle 






grinding 


I, 


396 


engine 


v, 


339 


importance of 


I, 


365 


Twist drills 


v, 


145 


noisy 


I, 


398 


Two-cycle motor diagram 


I, 


78 


number per cylinder 


I, 


377 


Two-cycle motorcycle engine 


v, 


291 


removing 


I, 


390 


Two-cylinder motor 


I, 37 


,41 


summary 


I, 


365 


Two-cylinder motorcycle 






taking out 


I, 


399 


engine V, 


, 272, 


297 


Valve cage I. 


p 182, 


405 


Two-stroke cycle 


I, 16 


>, 78 


Valve caps 


I, 


407 


Two-wheel trailers 


VI, 


257 


Valve enclosures 


I, 


399 



Note.— For page numbere see foot of pages. 



471 



Digitized by 



Google 



36 



INDEX 



Vol. Page 

Valve gears steam cars V, 367 

Valve guides I, 406 

Valve-key slots, cutting I, 396 

Valve mechanism I, 365 

exhaust system I, 417 

poppet-valve gears I, 370 

rotating valves I, 416 

sliding-sleeve valves I, 409 

Valve movement, lead and 

lag of VI, 32 

Valve ports, large I, 73 

Valve spring I, 391 

Valve-stem clearance I, 386 

Valve system parts I, 403 

Valve timing I, 384; V, 337; VI, 28, 32 

automobiles I, 384 

motorcycles V, 337 

tractors VI, 28, 32 

Valve timing gears I, 400 

Valve troubles of motorcycles V, 333 

Valves in motorcycle V, 326 

Valves in tractors VI, 147 

Valves and valve timing VI, 28 

camshaft and timing gear VI, 29 

lead and lag of valve 

movement VI, 32 
need of closely checking 

valves VI, 34 
placing of valves VI, 28 
sixteen-valve engine VI, 34 
timing valves VI, 31 
valve details VI, 28 
Vaporizing fuel VI, 38 
mixing gas and air VI, 39 
spraying necessary VI, 38 
Velie, firing order and igni- 
tion advance III, 92 
Venturi-tube mixing chamber I, 244 
Vertical motors VI, 103 
Hold and Tracklayer VI, 103 
Moline VI, 104 
Parrett VI, 104 
Vertical weldings V, 41 
Vibrator III, 20 
Vibrator coils, summary III, 186 
Vises V, 261 
Volt-ammeter VI, 394 
Voltage II, 404 

Note.— For page numbers see foot of pages. 



Vol. Page 

Voltage and amperage VI, 76 

Voltage drop II, 383; III, 94 

Voltage readings, how to take IV, 199 
Voltage and spark control 

devices III, 18 

Voltage standards III, 218 

Voltage of starting systems III, 223 
Voltage tests III, 264; IV, 198, 

200, 235, 237, 292, 295 
Voltmeter tests IV,j 198, 200, 235, 

237, 292, 295 

Vulcanization of tires II, 339 

Vulcanizers, retreading II, 346 

Vulcanizing kettles II, 344 

Vulcanizing outfits II, 341 

W 

Wagner system IV, 111 

single-unit IV, 111 

two-unit IV, 121 
Ward-Leonard automatic 

cut-out III, 217 

Wasp aviation motor I, 89 

Water-cooled aviation motors I, 91 

Water cooling I, 424 

anti-freezing solutions I, 437 

circulation I, 431 

fans I, 436 

radiators and piping I, 427 

Water-jacketing I,' 242, 425 

Water jackets, repairing 

cracked I, 179 

Water pump V, 407 
Water supply for public 

garages V, 249 

Water-tube boilers V, 382 

Waterproof plugs III, 28 

Watt's diagram of work I, 54 

Webber automatic carburetor I, 273 
Weld V, 19, 42 
Welding (see Oxy-acetylene 
welding practice 

I, 179, 220; V, 11, 40, 109 
Welding aluminum V, 78 
Welding apparatus V, 24 
Welding in automobile re- 
pair shops V, 11 
electric processes V, 21 



472 



Digitized by 



Google 



INDEX 



37 



Welding in automobile re- 
pair shops (con- 
tinued) 
miscellaneous processes 
oxy-acetylene process 
technic of oxy-acetylene 
welding 
Welding blowpipes 
Welding brass and bronze 
Welding cast iron 
Welding copper 
Welding different metals 
aluminum welding 
brass and bronze welding 
cast-iron welding 
copper welding 
malleable-iron welding 
pre-heating 
properties of metals 
steel welding 
Welding flame 
Welding flux 
Welding heavy sheet 
Welding heavy steel forg- 
ings and steel cast- 
ings 
Welding job, simple 
Welding malleable iron 
Welding processes 
Welding rods 
Welding steel 
Welds in heavy sheet 
Welds in light sheet 
Westcott, firing order and 

ignition advance 
Westinghouse ignition unit 
Westinghouse inherently 
controlled genera- 
tor 
Westinghouse starting 

switch 
Westinghouse system 
double-unit 
single-unit 



Vol. Page 



V, 
V, 



86 
13 



V, 24 
V, 17, 26 
V, 84 
V, 
V, 

v, 
v, 
v, 
v, 
v, 
v, 
v, 
v, 
v, 
v, 
v, 
v, 



82 
44 
78 
84 
69 
82 
77 
50 
44 
53 
35 
19 
63 



V, 67 

V, 24 

V, 77 

V, 11 
V, 18, 39 

V, 53 

V, 64 

V, 59 

III, 92 

III, 101 



III, 209 

III, 234 

IV, 135 
IV, 139 
IV, 135 



II, 


107 


II, 


298 


II, 


286 


II, 


361 


II, 


305 


II, 


284 


VI, 


215 


II, 


82 



92 



III, 38 



Vol. Page 
Wheel pullers II, 305 

Wheel sizes II, 284 

Wheel troubles and repairs II, 305 
Wheels II, 107, 284 

action in turning 
commercial-car wheels 
pleasure-car wheels 
summary of instructions 
troubles and repairs 
wheel sizes 
White delivery wagon 
Whiton gear-cutting machine II, 
Willys-Overland, firing 
order and ignition 
advance III, 

Winton HI, 92, 287, 293 

Winton spring II, 199 

Wiring connections of igni- 
tion system 
Wiring diagrams (see spe- 
cial wiring diagram 
indexes in Vols. 
Ill and IV) 
Wiring in electrical equip- 
ment III, 9: 
Wiring of magnetos 
Wiring tests 
Woodruff keys 
Work benches 
Work vises 

Workstand equipment 
Worm drive 
electric cars 
gasoline trucks 
Worm-gear transmission 

II, 92, 115; VI, 190, 240 
Worm type steering gear II, % 115 

Wrist pins and bushings, 

freeing I, 191 



3; IV, 


264 


VI, 


94 


in, 


359 


v, 


158 


V, 115, 


,257 


v, 


116 


II, 


257 


U, 237, 


303 


VI, 


303 


VI, 


237 



Zenith carburetors 



I, 252 



Note. — For page numbers see foot of pages. 



473 



Digitized by 



Google 



Digitized by VjOOQ IC 



Digitized by VjOOQIC 



Digitized by VjOOQIC 



Digitized by VjOOQIC 



Digitized by VjOOQIC