Chapter I: Front Matter

THE PETROL ENGINE

_BOOKS FOR MOTOR ENGINEERS._

=Electrical Ignition for Internal Combustion Engines.= By =M. A. Codd=. 109 illus., 163 pp., cr. 8vo. 3_s._ net.

Introduction—Principle of Electric Flow—Batteries—Switches—Coils—Auto-Tremblers—Lodge Ignition—Distributors—Magneto Ignition—High Tension Magnetos—Faults and Remedies—Magneto Repairs—Induction Coil Design—Index.

=Dynamo Lighting for Motor Cars.= By =M. A. Codd=, Author of “Electrical Ignition for Internal Combustion Engines.” 128 illus., vi + 96 pp. 8vo. 2_s._ 6_d._ net.

Introduction and General Principles—Fitting the System—Wiring the Car—Permanent Magnet System—Permanent and Electro-Magnet System—Electro-Magnetically Governed System—Electro-Magnetically Controlled System—Mechanically Controlled System—Hot Wire Controlled System—Some useful Accessories—Upkeep, Maintenance, and Location of Faults—Index.

=English-French and French-English Dictionary of the Motor Car, Cycle and Boat.= By =Frederick Lucas=. 171 pp., cr. 8vo. 2_s._ net.

=Motor Cycles, Side Cars and Cycle Cars=, Construction, Management and Repair. By =V. W. Page=, M.E. A comprehensive non-technical treatise, defining all forms of the lighter self-propelled vehicles, principles of operation, construction, and practical application of component parts. 8vo, 344 illus., 550 pp. (_New York._) 6_s._ 6_d._ net.

=The Modern Gasolene Automobile=, its Design, Construction, Maintenance and Repair. By =Victor W. Page=, M.E., late Technical Editor of the “Automobile Journal.” 500 illus., 693 pp., 8vo. (_New York._) 12_s._ net.

=Drawings for Medium Sized Repetition Work=, with Examples of Drawings for Motor-Car Parts. By =R. D. Spinney=, A.M.I.Mech.E. 47 illus., 130 pp., 8vo. 3_s._ 6_d._ net.

=Motor Body Building= in all its branches. By =C. W. Terry=, Organizer and Inspector of the City and Guilds of London Institute. With additional matter by =Arthur Hall=, Graduate member of “The Institute of British Carriage Manufacturers,” 1st class certificate in honours of the City and Guilds of London Institute, and other awards; Instructor in Motor Body Building, Municipal Technical College, Brighton, etc., etc. Medium 8vo, 256 pp., 15 illus., 5 plates. 10_s._ 6_d._ net.

E. & F. N. SPON, LTD., 57 HAYMARKET, LONDON, S.W.

The Petrol Engine

A Text-book dealing with the Principles
of Design and Construction, with
a Special Chapter on the
Two-stroke Engine

By

FRANCIS JOHN KEAN

B.SC. (LOND.); M.I.M.E.

First-Class Honourman in Engineering; Head of the Motor Car Engineering
Department of the Polytechnic School of Engineering, Regent Street,
London, W.; Formerly Lecturer on Experimental Engineering
at McGill University, Montreal, Canada

71 ILLUSTRATIONS

[Colophon]

London
E. & F. N. SPON, LIMITED, 57 HAYMARKET

New York
SPON & CHAMBERLAIN, 123 LIBERTY STREET

1915

CONTENTS

PAGE

LIST OF ILLUSTRATIONS ix

PREFACE xiii

CHAPTER I

GENERAL PRINCIPLES—
Explosive Mixtures 1
The Meaning of Suction 2
The Meaning of Compression 3
The Meaning of a Stroke 3
The Otto Cycle 5

CHAPTER II

DESCRIPTION OF A TYPICAL PETROL ENGINE—
The Cylinder 8

CHAPTER III

ENGINE DETAILS—
The Piston 17
The Connecting Rod 21
The Crankshaft 23
The Flywheel 25

CHAPTER IV

THE VALVES—
Poppet Valves 29
Sleeve Valves 31
The Camshafts and Eccentric Shafts 33
The Timing Wheels 37
The Crankchamber 38

CHAPTER V

THE CARBURETTOR AND CARBURATION—
The Float Chamber 44
The Petrol Jet and Choke Tube 46
The Mixing Chamber and Throttle Valve 47
Recent Improvements in Carburettors 47
Pressure Feed and Gravity Feed 50

CHAPTER VI

IGNITION AND IGNITION DEVICES—
The Sparking Plug 51
The High Tension Magneto 52
The Ignition Coil 57
Wiring Diagram for Magneto Ignition System 60
Wiring Diagram for a Coil Ignition System 60
Timing the Ignition 62

CHAPTER VII

LUBRICATION—
Properties of Oils 63
Splash System of Lubrication 63
Improved System of Splash Lubrication 64
Forced Lubrication 65

CHAPTER VIII

COOLING—
Natural or Thermo-Syphon Circulation 69
Forced or Pump Circulation 71

CHAPTER IX

THE POINTS OF A GOOD ENGINE—
Choosing the Number of Cylinders 75
The Question of the Valves 77
Economy and Durability 79

CHAPTER X

TWO-STROKE ENGINES—
The Two-port Two-stroke Engine 80
The “Kean” Duplex Air Scavenging Engine 85
The Twin-cylinder Two-stroke Engine 96

CHAPTER XI

HORSE-POWER AND THE INDICATOR DIAGRAM—
Work 98
Power 98
Brake Horse-power 99
Rated Horse-power 100
Indicated Horse-power 101
The Indicator Diagram 102

CHAPTER XII

LIQUID FUELS—
Petrol 108
Benzol 108
Alcohol 109
Paraffin 109
Thermal Efficiency 110