A TEXTBOOK OF

AUTOMOBILE ENGINEERING

(An ISO 9001:2008 Company)

BENGALURU ● CHENNAI ● COCHIN ● GUWAHATI ● HYDERABAD JALANDHAR ●  KOLKATA ●  LUCKNOW ●  MUMBAI ●  RANCHI ● NEW DELHI BOSTON (USA) ●  ACCRA (GHANA) ●  NAIROBI (KENYA)

A TEXTBOOK OF AUTOMOBILE ENGINEERING © by Laxmi Publications (P) Ltd. All rights reserved including those of translation into other languages. In accordance with the Copyright (Amendment) Act, 2012, no part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise. Any such act or scanning, uploading, and or electronic sharing of any part of this book without the permission of the publisher constitutes unlawful piracy and theft of the copyright holder’s intellectual property. If you would like to use material from the book (other than for review purposes), prior written permission must be obtained from the publishers.

Typeset at Goswami Associates, Delhi First Edition: 2007; Reprint: 2008, 2009, 2010, 2011, 2012, 2013, Second Edition: 2014, 2015, 2016, 2017 Edition: 2018 ISBN 978-81-7008-991-9 Limits of Liability/Disclaimer of Warranty: The publisher and the author make no representation or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties. The advice, strategies, and activities contained herein may not be suitable for every situation. In performing activities adult supervision must be sought. Likewise, common sense and care are essential to the conduct of any and all activities, whether described in this book or otherwise. Neither the publisher nor the author shall be liable or assumes any responsibility for any injuries or damages arising here from. The fact that an organization or Website if referred to in this work as a citation and/or a potential source of further information does not mean that the author or the publisher endorses the information the organization or Website may provide or recommendations it may make. Further, readers must be aware that the Internet Websites listed in this work may have changed or disappeared between when this work was written and when it is read.

Branches

All trademarks, logos or any other mark such as Vibgyor, USP, Amanda, Golden Bells, Firewall Media, Mercury, Trinity, Laxmi appearing in this work are trademarks and intellectual property owned by or licensed to Laxmi Publications, its subsidiaries or affiliates. Notwithstanding this disclaimer, all other names and marks mentioned in this work are the trade names, trademarks or service marks of their respective owners.

Published in India by

Laxmi Publications (P) Ltd.

(An ISO 9001:2008 Company) 113, GOLDEN HOUSE, DARYAGANJ, NEW DELHI - 110002, INDIA Telephone : 91-11-4353 2500, 4353 2501 Fax : 91-11-2325 2572, 4353 2528 www.laxmipublications.com [email protected]

&

Bengaluru

080-26 75 69 30

&

Chennai

044-24 34 47 26, 24 35 95 07

&

Cochin

0484-237 70 04,

405 13 03

&

Guwahati

0361-254 36 69,

251 38 81

&

Hyderabad

040-27 55 53 83, 27 55 53 93

&

Jalandhar

0181-222 12 72

&

Kolkata

033-22 27 43 84

&

Lucknow

0522-220 99 16

&

Mumbai

022-24 93 12 61

&

Ranchi

0651-220 44 64

CONTENTS Chapter

Pages

1.

1—13

INTRODUCTION 1.1. 1.2. 1.3. 1.4. 1.5. 1.6.

2.

Introduction to an Automobile Brief History of Automobile Classification of Automobiles Parts of an Automobile Description of an Automobile Performance of an Automobile Short Answer Questions Highlights Objective Type Questions Theoretical Questions

... ... ... ... ... ... ... ... ... ...

POWER UNIT—AUTOMOBILE ENGINES

1 1 3 5 7 8 11 12 13 13

14—269

I. Introduction to Internal Combustion Engines 2.1. 2.2. 2.3. 2.4. 2.5. 2.6. 2.7. 2.8. 2.9. 2.10. 2.11. 2.12. 2.13. 2.14. 2.15. 2.16. 2.17.

Heat Engines Development of I.C. Engines Classification of I.C. Engines Application of I.C. Engines Engine Cycle-Energy Balance Basic Idea of I.C. Engines Different Parts of I.C. Engines Terms Connected with I.C. Engines Working Cycles Indicator Diagram Four Stroke Cycle Engines Two Stroke Cycle Engines Intake for Compression Ignition Engines Comparison of Four Stroke and Two Stroke Cycle Engines Comparison of Spark Ignition (S.I.) and Compression Ignition (C.I.) Engines Comparison between a Petrol Engine and a Diesel Engine How to Tell a Two Stroke Cycle Engine from a Four Stroke Cycle Engine ?

... ... ... ... ... ... ... ... ... ... ... ... ... ...

15 17 17 20 21 22 23 48 50 51 51 57 59 60

... ...

61 63

...

63

... ...

64 64

II. Combustion in S.I. Engines 2.18. 2.19.

Introduction to Combustion in S.I. Engines Combustion Phenomenon (v)

( vi )

Chapter

Pages

2.20. 2.21. 2.22. 2.23. 2.24. 2.25. 2.26. 2.27.

Effect of Engine Variables on Ignition Lag Spark Advance and Factors Affecting Ignition Timing Pre-ignition Detonation Performance Number (PN) Highest Useful Compression Ratio (HUCR) Combustion Chamber Design—S.I. Engines Some Types of Combustion Chambers

2.28. 2.29. 2.30. 2.31. 2.32. 2.33. 2.34.

Introduction to Combustion in C.I. Engines Combustion Phenomenon in C.I. Engines Fundamentals of the Combustion Process in Diesel Engines Delay Period (or Ignition Lag) in C.I. Engines Diesel Knock C.I. Engine Combustion Chambers Cold Starting of C.I. Engines

2.35. 2.36. 2.37. 2.38. 2.39. 2.40. 2.41.

General Aspects Intake for Two stroke Cycle Engines Scavenging Process Scavenging Parameters Scavenging Systems Crankcase Scavenging Scavenging Pumps and Blowers

... ... ... ... ... ... ... ...

67 67 68 71 74 74 74 81

... ... ... ... ... ... ...

86 87 90 94 96 97 104

... ... ... ... ... ... ...

105 109 110 112 113 116 117

III. Combustion in C.I. Engines

IV. Two Stroke Engines

V. Fuels for I.C. Engines 2.42. 2.43.

Conventional Fuels (for I.C. Engines) Alternative Fuels for I.C. Engines

... ...

118 137

2.44. 2.45. 2.46. 2.47. 2.48. 2.49. 2.50.

VI. Supercharging of I.C. Engines Purpose of Supercharging Supercharging of S.I. Engines Supercharging of C.I. Engines Modification of an Engine for Supercharging Superchargers Supercharging Arrangements Turbochargers

... ... ... ... ... ... ...

149 151 156 158 158 158 159

... ... ... ...

167 167 170 180

... ... ...

182 184 185

2.51. 2.52. 2.53. 2.54. 2.55. 2.56. 2.57.

VII. Testing and Performance of I.C. Engines Introduction to Testing and Performance of I.C. Engines Performance Parameters Basic Measurements Engine Performance Curves Comparison of Petrol and Diesel Engines—Fuel Consumption, Load Outputs and Exhaust Composition Governing of I.C. Engines Noise Abatement

( vii )

Chapter 2.58. 2.59. 2.60. 2.61. 2.62. 2.63. 2.64. 2.65. 2.66. 2.67. 2.68. 2.69. 2.70. 2.71. 2.72. 2.73. 2.74.

3.

Pages VIII. Miscellaneous Engines Dual-fuel and Multi-fuel Engines Stratified Charge Engine Stirling Engine The Wankel Rotary Combustion (RC) Engine Variable Compression Ratio (VCR) Engines Free-Piston Engine Plant IX. Air Pollution from I.C. Engines and its Control Introduction to Air Pollution from I.C. Engines Pollutants Spark Ignition (S.I.) Engine Emissions S.I. Engine Emission Control Diesel Engine Emissions Diesel Smoke and Control Comparison of Gasoline and Diesel Emissions Zero Emission Air Pollution from Gas Turbines and its Control Effects of Engine Emissions on Human Health Comparative Data of Constructional Features of Engines of Some India Vehicles Short Answer Questions Highlights Objective Type Questions Theoretical Questions Unsolved Examples

... ... ... ... ... ...

196 201 203 208 214 217

... ... ... ... ... ... ... ... ... ...

219 219 222 226 234 236 239 239 240 241

... ... ... ... ... ...

242 244 246 251 262 268

FUEL SUPPLY SYSTEM 3.1.

270—350

Air, Fuel and Exhaust Gases Circuits of Petrol and Diesel Engines

...

270

... ... ... ... ... ... ... ... ... ... ...

272 273 273 274 275 276 277 278 286 296 300

... ... ...

315 316 316

I. S.I. Engines 3.2. 3.3. 3.4. 3.5. 3.6. 3.7. 3.8. 3.9. 3.10. 3.11. 3.12.

Introduction to Carburetion and Carburettors Induction System Factors Influencing Carburetion Mixture Requirements Distribution Transient Mixture Requirements A Simple or Elementary Carburettor Complete Carburettor Carburettors Petrol Injection Theory of Simple Carburettor II. C.I. Engines

3.13. 3.14. 3.15.

Introduction to Fuel Injection Systems for C.I. Engines Functional Requirements of an Injection System Functions of a Fuel Injection System

( viii )

Chapter 3.16. 3.17. 3.18. 3.19. 3.20. 3.21. 3.22. 3.23.

4.

Fuel Injection Systems Fuel Pump and Fuel Injector (Atomiser) Types of Nozzles and Fuel Spray Patterns Engine Starting Systems Fuel Injection Computation in C.I. Engines Troubleshooting of a Fuel System Troubleshooting of Carburettor Comparative Diesel Engine Fuel System Data of Some Indian Automobiles Short Answer Questions Highlights Objective Type Questions Theoretical Questions Unsolved Examples

... ... ... ... ... ... ...

317 321 326 329 330 338 339

... ... ... ... ... ...

342 342 345 346 348 349

ENGINE FRICTION AND LUBRICATION SYSTEMS 4.1. 4.2. 4.3. 4.4. 4.5. 4.6. 4.7. 4.8.

5.

Pages

Introduction Total Engine Friction Effect of Engine Parameters on Engine Friction Determination of Engine Friction Lubrication Lubrication Systems Crankcase Ventilation Lubrication System of Some Indian Vehicles Short Answer Questions Highlights Objective Type Questions Theoretical Questions

351—372 ... ... ... ... ... ... ... ... ... ... ... ...

COOLING SYSTEMS 5.1. 5.2. 5.3. 5.4. 5.5. 5.6. 5.7. 5.8. 5.9. 5.10. 5.11.

Necessity of Engine Cooling Areas of Heat Flow in Engines Gas Temperature Variation Heat Transfer, Temperature Distribution and Temperature Profiles Effects of Operating Variables on Engine Heat Transfer Cooling Air and Water Requirements Cooling Systems Components of Water Cooling System Specifications for the Cooling System of an Engine Troubleshooting of Cooling System Cooling System Data of Some Indian Vehicles Short Answer Questions Highlights Objective Type Questions Theoretical Questions

351 351 353 354 354 361 368 368 369 369 370 371

373—404 ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...

373 375 375 376 381 382 384 394 399 400 400 401 402 403 404

( ix )

Chapter 6.

Pages

CHASSIS AND SUSPENSION

405—461 A. Chassis

6.1. 6.2. 6.3. 6.4. 6.5.

Introduction to Chassis Classification of Chassis Frame Body Vehicle Dimensions

... ... ... ... ...

405 406 409 413 415

... ... ... ... ... ... ... ... ... ... ... ...

415 416 416 417 418 422 425 439 452 457 457 459

B. Suspension 6.6. 6.7. 6.8. 6.9. 6.10. 6.11. 6.12. 6.13.

7.

TRANSMISSION SYSTEM 7.1. 7.2. 7.3. 7.4. 7.5. 7.6. 7.7.

8.

Introduction to Suspension System Functions/Objects of a Suspension System Requirements of a Suspension System Elements of a Suspension System Springs Dampers (or Shock Absorbers) Suspension Systems Wheels and Tyres Short Answer Questions Highlights Objective Type Questions Theoretical Questions

Introduction to Transmission System Clutch Gear Box (Transmission) Propeller Shaft Universal Joints Final Drive and Differential Rear Axles Short Answer Questions Highlights Objective Type Questions Theoretical Questions

462—527 ... ... ... ... ... ... ... ... ... ... ...

STEERING AND FRONT AXLE 8.1. 8.2. 8.3. 8.4. 8.5. 8.6. 8.7. 8.8. 8.9.

A. Steering System Purpose of a Steering System Functions of a Steering System Requirements of a Good Steering System General arrangement of a Steering System Steering Gears Steering Ratio Reversibility Steering Geometry Wheel Alignment

462 464 479 500 504 507 511 516 521 522 525

528—558 ... ... ... ... ... ... ... ... ...

528 528 529 529 531 534 535 535 536

(x)

Chapter 8.10. 8.11. 8.12. 8.13. 8.14. 8.15. 8.16. 8.17. 8.18. 8.19. 8.20.

Pages Steering Mechanisms Understeering and Oversteering Steering Linkages Steering Wheel and Column Steering Arm Drag link Steering Stops Power-Steering Adjustment of Steering Geometry Steering Troubleshooting Comparative Steering Data of Some Indian Automobiles

... ... ... ... ... ... ... ... ... ... ...

539 542 543 545 545 546 546 546 550 551 551

... ... ... ... ... ... ... ...

552 552 553 553 554 556 557 557

B. Front Axle 8.21. 8.22. 8.23. 8.24.

9.

Introduction to Front Axle Construction of Front Axle Types of Front Axles Stub Axles Short Answer Questions Highlights Objective Type Questions Theoretical Questions

BRAKING SYSTEM 9.1. 9.2. 9.3. 9.4. 9.5. 9.6. 9.7. 9.8. 9.9. 9.10. 9.11. 9.12. 9.13. 9.14. 9.15. 9.16. 9.17. 9.18. 9.19. 9.20.

Introduction to Braking System Necessity of a Braking System Functions of Brakes Requirements of a Good Braking System Classification of Brakes Mechanical Brakes Hydraulic Brakes Power Brakes Brake Effectiveness Factors Controlling the Stop of an Automobile Arrangement of Brakes in Different Vehicles Brake Shoes and Linings Brake Drum Brake Shoe Holding Down Arrangements Brake Testers Brake Service Troubleshooting Chart of Hydraulic Brakes System Troubleshooting Chart of Air Brakes Troubleshooting Chart of Brake Shoes and Drums Comparative Brake Data of Some Indian Vehicles Short Answer Questions Highlights Objective Type Questions Theoretical Questions

559—588 ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...

559 559 560 560 560 561 563 569 576 576 577 577 578 578 579 580 581 581 582 583 583 585 586 587

( xi )

Chapter

Pages

10. AUTOMOTIVE ELECTRICAL SYSTEM 10.1.

Introduction to Electrical System

10.2. 10.3. 10.4.

Introduction to starting System The Battery Starting Motor (or Self-starter)

589—690 ...

589

... ... ...

591 591 608

... ... ...

615 615 621

... ... ... ... ... ... ... ... ... ... ... ...

626 627 627 627 628 635 637 638 641 643 644 647

... ... ... ... ... ... ... ...

649 649 653 661 676 681 683 688

I. Starting System

II. Charging system 10.5. 10.6. 10.7.

Introduction to Charging System Generator (Dynamo) Alternator (A.C. generator)

10.8. 10.9. 10.10. 10.11. 10.12. 10.13. 10.14. 10.15. 10.16. 10.17. 10.18. 10.19.

Introduction to Ignition System Purpose of Ignition System Requirements of an Ignition System Basic Ignition Systems Battery (or coil) Ignition System Magneto Ignition System Firing Order Ignition Timing Spark Plugs Limitations of Conventional Ignition Electronic Ignition Systems Troubleshooting of Ignition System

10.20. 10.21. 10.22. 10.23.

Introduction to Lighting and Accessory System Main Circuits of the Automobile Electrical System Lighting System Accessories Short Answer Questions Highlights Objective Type Questions Theoretical Questions

III. Ignition System

IV. Lighting and Accessory System

11. MAINTENANCE AND TROUBLESHOOTING OF AUTOMOBILE 11.1. 11.2.

Maintenance Troubleshooting Short Answer Questions Highlights Objective Type Questions Theoretical Questions

691—744 ... ... ... ... ... ...

12. MISCELLANY 12.1.

Gas Power Cycles

691 725 741 742 743 743

745—863 ...

745

( xii )

Chapter 12.2. 12.3. 12.4. 12.5. 12.6. 12.7.

Pages Automotive Gas Turbines Automobile Body and Safety Considerations Car Driving Fuel Saving Garage Tools and Equipment Technical Specifications of Automotive Vehicles Short Answer Questions Highlights Objective Type Questions Theoretical Questions

13. “UNIVERSITIES’ QUESTIONS (LATEST) WITH ANSWERS/SOLUTIONS”

... ... ... ... ... ... ... ... ... ...

771 786 790 801 804 825 859 859 860 862

864—901

ADDITIONAL OBJECTIVE TYPE QUESTIONS’ BANK

903—952

APPENDICES

953—980

INDEX

981—984

PREFACE TO THE SECOND EDITION I take pleasure in presenting the “Second Edition” of this book on “Automobile Engineering”. The warm reception which the previous edition has received is a matter of great satisfaction to me. In this edition, the book has been thoroughly revised; a new chapter (No. 13) namely “Universities Questions (Latest) with Answers/Solutions” has been added to make the book more useful to the readers. Any suggestions for improvement of the book are most welcome.

Er. R.K. Rajput (Author)

PREFACE TO THE FIRST EDITION The main objective of writing this book on the subject “Automobile Engineering” is to present to the student community, a book which contains comprehensive treatment of the subject matter in simple, lucid and direct language and envelopes an ample number of worked examples to illustrate the text. The book contains twelve chapters in all. All these chapters are saturated with much needed text, supported by simple and self-explanatory figures and worked examples, wherever required. At the end of each chapter Short Answer Questions, Highlights, Objective Type Questions, Theoretical Questions and Unsolved Examples have been added to make the book a comprehensive and complete unit in all respects. The book will prove to be a boon to the students preparing for engineering undergraduate, A.M.I.E. section B (India) and competitive examinations. The author’s thanks are due to his wife Ramesh Rajput for extending all cooperation during preparation of the manuscript. In the end the author wishes to express his gratitude to Shri R.K. Gupta, Chairman, Shri Saurabh Gupta, Managing Director, Laxmi Publications Pvt. Ltd., New Delhi for taking pains in bringing out the book with a very good presentation in a short span of time. Although every care has been taken to make the book free of errors both in text as well as in worked examples, yet the author shall feel obliged if any errors present are brought to his notice. Constructive criticism of the book will be warmly and thankfully welcomed. Er. R.K. Rajput (Author)

1 Introduction 1.1. Introduction to an automobile. 1.2. Brief history of automobile. 1.3. Classification of automobiles. 1.4. Parts of an automobile—mechanical portion—chassis and transmission—the engine—electrical system—body or carriage portion. 1.5. Description of an automobile. 1.6. Performance of an automobile—Short Answer Questions—Highlights—Objective Type Questions—Theoretical Questions.

1.1. INTRODUCTION TO AN AUTOMOBILE Automobile. An “automobile” is a self-propelled vehicle driven by an internal combustion engine and is used for transportation of passengers and goods on ground. Examples : Bus, car, jeep, truck, tractor, scooter, motor cycle. The modern automobile, in general, is essentially a transportation equipment unit. It consists of a “frame” supporting the “body” and certain “power developing and transmitting units” which are further supported by “tyres and wheels” through “springs and axles”. An “engine” supplies the power, which is delivered by the “transmission system” to the wheels through the clutch or fluid coupling. Automobile engineering. Automobile (or automotive) engineering is a branch of engineering in which we study all about the automobiles and have practice to propel them. — Mobile or motive means one which can move. Automobile or automotive means one which itself can move. The different names for the automobile are : l Auto l Automobile l Autocar l Autobuggy l Car l Motor l Motor car l Motor vehicle l Motor coach l Motor wagon l Horseless coach. 1.2. BRIEF HISTORY OF AUTOMOBILE The famous years in early automobile history are as follows : Year Event l 1769 French engineer Captain Nicholas Cugnot of France built the first road vehicle propelled by its own power (Attained a speed of about 2.5. m.p.h. in 15 minutes). l 1801 First steam carriage built by Richard Trevithick in England. l 1804 Oliver Evans built the finest American self-propelled steam vehicle. l 1827 Onesiphare Pacqueur of France invented first differential. l 1832 First 3-speed Transmission patented by W.H. James in England. l 1880 German and French efforts developed an internal combustion engine vehicle (which was used to carry fruits). The present day automobile is the development of this vehicle.

1

875.00