Today’s Technician : Automotive Engine Repair and Rebuilding : Classroom Manual

CLASSROOM

MANUAL

For Automotive Engine Repair & Rebuilding

SIXTH EDITION

Australia • Brazil • Japan • Korea • Mexico • Singapor e • Spain • United Kingdom • United States

CLASSROOM

MANUAL

For Automotive Engine Repair & Rebuilding

SIXTH EDITION

Chris Hadfield

Director, Minnesota Transportation Center of Excellence

Randy Nussler

South Puget Sound Community College & New Market Skills Center

Repair & Rebuilding, Sixth Edition

Chris Hadfield

Randy Nussler

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Classroom Manual ISBN: 978-1-305-95811-1

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Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii

CHAPTER 1 Automotive Engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Terms to Know 1 • Introduction 1 • Basic Engine Operation 2 • Cooling System 6

• Lubrication System 6 • Engine Breathing 6 • Engine Performance 7 • Cylinder

Head 9 • Timing Mechanism 10 • Engine Block 11 • Summary 12 • Review

Questions 13

CHAPTER 2 Engine Repair and Rebuilding Industry . . . . . . . . . . . . . 15

Terms to Know 15 • Introduction 15 • Full-Service Repair Facilities 15

• Machine Shop and Engine Rebuild Facilities 17 • Engine Repair and Replacement

Specialty Facilities 18 • Engine and Component Remanufacturing Facilities 19

• Summary 20 • Review Questions 20

CHAPTER 3 Theory of Engine Operation . . . . . . . . . . . . . . . . . . . . . 22

Terms to Know 22 • Introduction 23 • Major Engine Components 23 • Engine

Operating Principles 27 • Behavior of Liquids and Gases 30 • Pressure and

Vacuum 30 • Boyle’s Law 31 • Engine Operation 31 • Engine Classifications 34

• Engine Vibration 38 • Engine Displacement 40 • Direction of Crankshaft

Rotation 42 • Engine Measurements 42 • Other Engine Designs 49 • Engine

Identification 52 • Summary 56 • Review Questions 56

CHAPTER 4 Engine Operating Systems . . . . . . . . . . . . . . . . . . . . . . 59

Terms to Know 59 • Introduction 60 • The Starting System 60 • Lubrication

Systems 65 • Cooling Systems 76 • Cooling Fans 88 • Lubrication and Cooling

Warning Systems and Indicators 90 • Fuel System 94 • Automotive Fuels 98

• Summary 102 • Review Questions 103

CHAPTER 5 Factors Affecting Engine Performance . . . . . . . . . . . . 105

Terms to Know 105 • Introduction 105 • Spark Plugs 106 • Combustion Chamber

Sealing 107 • Fuel and Combustion 111 • Engine Noises 115 • Summary 116

• Review Questions 116

CHAPTER 6 Engine Materials, Fasteners, Gaskets, and Seals . . . . . 118

Terms to Know 118 • Introduction 118 • Engine Materials 119 • Manufacturing

Processes 122 • Fasteners 126 • Gaskets, Seals, Sealants, and Adhesives 131

• Summary 139 • Review Questions 139

CHAPTER 7 Intake and Exhaust Systems. . . . . . . . . . . . . . . . . . . . . 141

Terms to Know 141 • Introduction 141 • Air Induction System 142 • Air Intake

Ductwork 143 • Air Cleaner/Filter 143 • Intake Manifold 146 • Intake Manifold

Tuning 147 • Vacuum Basics 149 • Vacuum Controls 149 • Turbochargers 150

• Superchargers 155 • Exhaust System Components 159 • Mufflers 163

• Summary 165 • Review Questions 166

CONTENTS

CHAPTER 8 Engine Configurations, Mounts,

and Remanufactured Engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

Terms to Know 168 • Introduction 168 • Engine Configurations 168

• Engine Mounts 170 • Remanufactured Engines 172 • Summary 175 • Review

Questions 175

CHAPTER 9 Cylinder Heads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

Terms to Know 177 • Introduction 177 • Cylinder Heads 178 • Cylinder

Head Component Relationships 189 • Combustion Chamber Designs 190

• The Combustion Process 194 • Multivalve Engines 197 • Summary 198

• Review Questions 198

CHAPTER 10 Camshafts and Valvetrains . . . . . . . . . . . . . . . . . . . . . 200

Terms to Know 200 • Introduction 200 • Summary 214 • Review Questions 215

CHAPTER 11 Timing Mechanisms . . . . . . . . . . . . . . . . . . . . . . . . . . 217

Terms to Know 217 • Introduction 217 • Valve Timing Systems 217 •

Chain-Driven Systems 220 • Belt-Driven Systems 221 • Gear-Driven Systems 223

• Variable Valve Timing Systems 224 • Variable Valve Lift (Cam-Shifting) 226

• Variable Valve Timing and Lift Systems 226 • Summary 231 • Review Questions 231

CHAPTER 12 Engine Block Construction. . . . . . . . . . . . . . . . . . . . . 233

Terms to Know 233 • Introduction 233 • Block Construction 235 • Crankshaft 240

• Camshaft 245 • Lifter Bores 245 • Harmonic Balancing 245 • Flywheel 246

• Short Blocks, Long Blocks, and Crate Engines 247 • Summary 248

• Review Questions 248

CHAPTER 13 Pistons, Rings, Connecting Rods, and Bearings . . . . . 250

Terms to Know 250 • Introduction 250 • Bearings 250 • Camshaft and Balance

Shaft Bearings 257 • Balance Shafts 257 • Pistons 257 • Piston Designs and

Construction 263 • Piston Rings 266 • Connecting Rods 268 • Summary 270

• Review Questions 270

CHAPTER 14 Alternative Fuel and Advanced

Technology Vehicles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272

Terms to Know 272 • Introduction 272 • Alternative Fuel Vehicle Use 273

• Propane Vehicles 273 • E85 and Flexible Fuel Vehicles 276 • Compressed

Natural Gas Vehicles 278 • The Honda Civic GX CNG Vehicle 283 • Electric

Vehicles 284 • Hybrid Electric Vehicles 286 • Hev Operation 287 • Plug-In Hybrid

Electric Vehicles 294 • Fuel Cell Vehicles 295 • Summary 295 • Review Questions 296

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314

vii

PREFACE

Thanks to the support the Today’s TechnicianTM series has received from those who teach

automotive technology, Cengage Learning, the leader in automotive-related textbooks, is

able to live up to its promise to provide new editions of the series every few years. By

revising this series on a regular basis, we can respond to changes in the industry, changes

in technology, changes in the certification process, and to the ever-changing needs of

those who teach automotive technology.

The Today’s TechnicianTM series features textbooks and digital learning solutions that

cover all mechanical and electrical systems of automobiles and light trucks. The individual

titles correspond to the ASE (National Institute for Automotive Service Excellence) certification areas and are specifically correlated to the 2016 standards for Automotive Service

Technicians (AST), Master Automotive Service Technicians (MAST), and Maintenance

and Light Repair (MLR).

Additional titles include remedial skills and theories common to all of the certification

areas and advanced or specific subject areas that reflect the latest technological trends,

such as this updated title on engine repair.

Today’s Technician: Automotive Engine Repair and Rebuilding, 6th edition, is designed

to give students a chance to develop the same skills and gain the same knowledge that

today’s successful technicians have. This edition also reflects the changes in the guidelines

established by the National Automotive Technicians Education Foundation (NATEF).

The purpose of NATEF is to evaluate technician training programs against standards

developed by the automotive industry and recommend qualifying programs for certification (accreditation) by ASE. Programs can earn ASE certification upon NATEF’s recommendation. NATEF’s national standards reflect the skills that students must master. ASE

certification through NATEF evaluation ensures that certified training programs meet or

exceed industry-recognized, uniform standards of excellence.

The technician of today and for the future must know the underlying theory of all

automotive systems and be able to service and maintain those systems. Dividing the material into two volumes, a Classroom Manual and a Shop Manual, provides the reader with

the information needed to begin a successful career as an automotive technician without

interrupting the learning process by mixing cognitive and performance learning objectives into one volume.

The design of Cengage’s Today’s TechnicianTM series was based on features that are

known to promote improved student learning. The design was further enhanced by a

careful study of survey results, in which the respondents were asked to value particular

features. Some of these features can be found in other textbooks, while others are unique

to this series.

Each Classroom Manual contains the principles of operation for each system and

subsystem. The Classroom Manual also contains discussions on design variations of key

components used by the different vehicle manufacturers. It also looks into emerging

technologies that will be standard or optional features in the near future. This volume is

organized to build upon basic facts and theories. The primary objective of this volume is

to allow the reader to gain an understanding of how each system and subsystem operates.

This understanding is necessary to diagnose the complex automobiles of today and tomorrow. Although the basics contained in the Classroom Manual provide the knowledge

needed for diagnostics, diagnostic procedures appear only in the Shop Manual. An

viii

understanding of the underlying theories is also a requirement for competence in the

skill areas covered in the Shop Manual.

A spiral-bound Shop Manual delivers hands-on learning experiences with step-bystep instructions for diagnostic and repair procedures. Photo Sequences are used to illustrate some of the common service procedures. Other common procedures are listed and

are accompanied with fine line drawings and photos that allow the reader to visualize and

conceptualize the finest details of the procedure. This volume also contains the reasons

for performing the procedures, as well as when that particular service is appropriate.

The two volumes are designed to be used together and are arranged in corresponding

chapters. Not only are the chapters in the volumes linked together, the contents of the

chapters are also linked. The linked content is indicated by marginal callouts that refer

the reader to the chapter and page where the same topic is addressed in the companion

volume. This valuable feature saves users the time and trouble of searching the index or

table of contents to locate supporting information in the other volume. Instructors will

find this feature especially helpful when planning the presentation of material and when

making reading assignments.

Both volumes contain clear and thoughtfully selected illustrations, many of which are

original drawings or photos specially prepared for inclusion in this series. This means that

the art is a vital part of each textbook and not merely inserted to increase the number of

illustrations.

The layout of Automotive Engine Repair & Rebuilding, 6th edition, is easy to follow

and consistent with the Today’s TechnicianTM series. Complex systems are broken into

easier-to-understand explanations. Industry standardized terms and vernacular are used

and explained in the text.

Jack Erjavec

HIGHLIGHTS OF THE NEW EDITION—CLASSROOM

MANUAL

The Classroom Manual for this edition of Today’s Technician: Automotive Engine Repair

and Rebuilding includes updated coverage of the NATEF AST, MAST, and MLR tasks

for engine repair and rebuilding. In addition to updated coverage of industry trends, new

information has been added on the following:

■ 0w16 oil

■ Engine design changes for gas direct injection (GDI)

■ EPDM belts

■ Stretch belts

■ Wet timing belts

■ Flat plane crankshafts

■ Cam-phaser design, operation, and service

■ Variable valve timing

■ Variable lift

■ Active fuel management

■ Variable cylinder displacement

HIGHLIGHTS OF THE NEW EDITION—SHOP MANUAL

Like all textbooks in the Today’s TechnicianTM series, the understanding acquired by reading the Classroom Manual is required for competence in the skill areas covered in the

Shop Manual. Service information related to the topics covered in the Classroom Manual

is included in this manual. In addition, several photo sequences are used to highlight

typical service procedures and provide the student the opportunity to get a realistic idea

of a procedure. The purpose of these detailed photo sequences is to show students what

to expect when they perform the same procedure. They can also provide a student with

familiarity of a system or type of equipment they may not be able to perform at their

school.

To stress the importance of safe work habits, Chapter 1 covers safety issues and has

been updated to include hybrid vehicle high-voltage safety. Included in this chapter are

common shop hazards, safe shop practices, safety equipment, and the legislation concerning and the safe handling of hazardous materials and wastes.

Chapter 2 covers special tools and procedures. Procedures include the use of engine

condition and diagnostic test equipment, precision engine measuring tools and specialty

measuring tools, along with engine reconditioning tools and equipment.

The subsequent Shop Manual chapters synch up with those in the Classroom Manual,

and the related content of each manual’s chapters is linked by use of page references in the

margins. This allows the student to quickly cross-reference the theory with the practical.

Redundancy between the Classroom Manual and the Shop Manual has been kept to a

minimum; the only time theory is discussed again is if it is necessary to explain the diagnostic results or as an explanation of the symptom. Currently accepted service procedures

are used as examples throughout the text. These procedures also served as the basis for the

job sheets that are included in the textbook at the end of each chapter. Updated coverage

in the Shop Manual addresses:

■ Engine pre-oiling

■ Engine break-in

■ 500-mile service for newly rebuilt engines

■ HEV service and safety

■ Concerns related to improper oil service on hydraulically controlled systems

CLASSROOM MANUAL

Features of the Classroom Manual include the following:

Upon completion and review of this chapter, you should understand and be able to describe:

Autoignition temperature

Bore

Bottom dead center (BDC)

Boyle’s law

Brake horsepower

Coil

Compression-ignition (CI)

engines

Compression ratio

Connecting rods

Crankshaft

Cycle

Detonation

Displacement

Dual overhead cam

(DOHC)

Engine

Efficiency

Engine bearings

Friction

Fuel injection

Glow plugs

Gross horsepower

Horsepower

Hybrid electric vehicle

(HEV)

Indicated horsepower

Internal combustion engine

Kinetic energy

Law of conservation of

energy

Mechanical efficiency

Net horsepower

Overhead cam (OHC)

Overhead valve (OHV)

Piston rings

Potential energy

Preignition

Reciprocating

Reed valve

Rotary valve

Spark-ignition (SI) engine

Stroke

Thermal efficiency

Thermodynamics

Top dead center (TDC)

Torque

Transmission

Transverse-mounted engine

Vacuum

Valve overlap

Volumetric efficiency (VE)

Wrist pin

CHAPTER 3

THEORY OF ENGINE OPERATION

■ Major engine components.

■ Basic engine operation.

■ Basic laws of physics involved with

engine operation.

■ Engine classifications according to

the number of cycles, the number of

cylinders, cylinder arrangement,

and valvetrain type.

■ The four-stroke cycle theory.

■ The different cylinder arrangements

and the advantages of each.

■ The different valvetrains used in

modern engines.

■ Engine measurement terms such as

bore and stroke, displacement,

compression ratio, engine efficiency,

horsepower and torque, horsepower

losses, mechanical efficiency, and

thermal efficiency.

■ The relationship between compression

ratio and engine power output.

■ Mechanical, volumetric, and thermal

efficiencies, and factors that affect

each.

■ The basic operation of alternative

engine designs, including two-stroke,

diesel, and stratified charge.

■ The internal components of a diesel

engine and how they differ from those

of a gas engine.

Terms To Know

11_ch03_hr_022-058.indd 22

256 Chapter 13

oil bearing clearances fall within the range of 0.0008 inch (0.0203 mm) to 0.002 inch

(0.0508 mm). These are just typical clearances; always check the manufacturer’s specifications

for the engine you are working on.

Bearings are a wear item. They are designed to wear and protect the crankshaft or

camshaft. They do wear out after high mileage and exposure to contaminated oil. When the

engine is disassembled for repairs, it is customary to replace the main, rod, and cam bearings.

When fitting new bearings, you will have to check the clearance to ensure that it is

within the specified range. We will discuss this procedure in Chapter 13 of the Shop

Manual.

Undersize and Oversize Bearings

When a crankshaft is worn lightly and polished to be usable, bearings that are 0.001 and

0.002 inch undersize are often available. If the crankshaft has been ground to repair serious

journal wear, undersize bearings can be fitted. These bearings are generally available in

0.010, 0.020, and 0.030 inch undersize. Metric undersized bearings may include 0.050,

0.250, 0.500, and 0.750 mm. Undersize means that the inside diameter of the bearings is

smaller, to fit the reduced diameter of the crankshaft journals.

Oversize bearings may be used when the block has been line bored to an oversized

diameter. Oversize bearings are often available in 0.010, 0.020, 0.030, and 0.040 inch.

Available metric oversized bearings are typically 0.250, 0.500, 0.750, and 1.000 mm. These

bearings have a larger outside diameter than the standard bearing. The use of oversize

and undersize bearings has decreased dramatically as component replacement has become

more cost-effective than many complex machining operations. Some bearings are stamped

with a code that allows the technician to check the size of the bearing that is currently in

use. New bearings come stamped from the factory with the size correlation on it. Some

engine blocks have a stamping on them that helps the technician indicate what size bearing came on the engine originally. If different sized bearings are installed in this type of

engine, the technician should change this mark or remove it.

Shop Manual

Chapter 13, page 588

Undersize bearings

have the same outside

diameter as standard

bearings, but the bearing material is thicker to

fit an undersize crankshaft journal.

Oversize bearings are

thicker than standard

to increase the outside

diameter of the bearing to fit an oversize

bearing bore. The inside

diameter is the same as

standard bearings.

Figure 13-11 Bearing crown maintains close clearances at the top

and bottom of the bearing, where most of the loads are applied.

Parting face

Bearing

crown

AUTHOR’S NOTE It has been my experience that most connecting rod and main

bearing failures are caused by contaminated engine oil or lack of lubrication. Often

the cause of failure is clear by the sludge in the oil pan, the coolant-contaminated

oil, or the lack of oil in the crankcase. Try to determine the cause of the failure if it

is premature. Most bearings should last the life of the engine; these days, that may

reach 150,000 to 200,000 miles (241,402 to 321,870 km). Be sure to discuss the

importance of regular oil and filter changes with your customers.

Figure 13-10 A multiplepiece thrust bearing.

h13 hr 250-271.indd 256 4/3/17 8:29 PM

Cognitive Objectives

These objectives outline the chapter’s contents

and identify what students should know and

be able to do upon completion of the chapter.

Each topic is divided into small units to

promote easier understanding and learning.

Cross-References to

the Shop Manual

References to the appropriate page

in the Shop Manual appear whenever

necessary. Although the chapters of the

two manuals are synchronized, material

covered in other chapters of the Shop

Manual may be fundamental to the

topic discussed in the Classroom

Manual.

Margin Notes

The most important terms to know are

highlighted and defined in the margin.

Common trade jargon also appears

in the margin and gives some of the

common terms used for components.

This helps students understand and

speak the language of the trade,

especially when conversing with an

experienced technician.

Author’s Note

This feature includes

simple explanations,

stories, or examples of

complex topics. These

are included to help

students understand

difficult concepts.

Terms to Know List

A list of key terms appears immediately

after the Objectives. Students will see

these terms discussed in the chapter.

Definitions can also be found in the

Glossary at the end of the manual.

116 Chapter 5

REVIEW QUESTIONS

Figure 5-17 The bearings on the left are worn down to the copper underlayer;

these created engine knocking from the bottom end.

SUMMARY

■ Proper engine performance requires that the

engine is mechanically sound and that its support

systems are functioning as designed.

■ The combustion chamber must be properly sealed

to provide good engine performance.

■ The valves, spark plug, rings, and head gasket seal

the combustion chamber.

■ The octane rating of gasoline describes its ability to

resist knocking; the higher the number, the greater

the resistance to knocking.

■ Higher volatility fuel should be used in the winter

to assist cold starts; lower volatility fuel should be

used in the summer to prevent excessive HC emissions and vapor lock.

■ Misfire, preignition, and detonation are three types

of abnormal combustion that can cause serious

engine damage.

■ Failures in the cooling or lubrication systems can

cause abnormal combustion or serious engine defects.

■ Normal engine wear will eventually lead to abnormal noises and reduced performance.

Short-Answer Essays

1. What components seal the combustion chamber?

2. What problems can occur from improper

combustion chamber sealing?

3. What effect will a burned valve have on engine

performance?

4. What does a gasoline’s octane rating describe?

5. What problems can occur when fuel with an

inappropriate volatility is used?

6. Define preignition.

7. Define detonation.

8. Describe some causes of abnormal combustion.

9. What engine problems can detonation lead to?

10. What causes abnormal engine noises?

Fill-in-the-Blanks

1. A leak past the _______________ gasket can cause

compromised engine performance.

2. The _______________ _______________,

_______________ _______________, and

_______________ in addition to the spark plug

and cylinder wall seal the combustion chamber.

3. Malfunctions in the _______________ system and

the _______________ system can cause engine

mechanical problems.

4. Three types of abnormal combustion are

_______________,_______________, and

_______________. Preignition occurs when a

flame front starts _______________ the spark.

5. _______________ is likely to burn a hole in the top

of the piston.

58111 ch05_hr_105-117.indd 116 2/13/17 12:11 PM

Summary

Each chapter concludes with

summary statements that

contain the important topics

of the chapter. These are

designed to help the reader

review the contents.

Review Questions

Short-answer essays,

fill-in-the-blanks, and multiplechoice questions follow each

chapter. These questions are

designed to accurately assess

the student’s competence in the

stated objectives at the beginning

of the chapter.

A Bit of History

This feature gives the student

a sense of the evolution of the

automobile. This feature not

only contains nice-to-know

information, but also should

spark some interest in the

subject matter.

110 Chapter 5

Misadjusted valves can also cause valve leakage and burning. If a valve is adjusted too

tightly, it will be held open longer than it was designed to. This can cause a reduction in

performance through poor sealing of the combustion chamber during the appropriate

strokes. In extreme cases, it can also cause the valves to burn if they are exposed to excessive temperatures.

Figure 5-8 A pitted valve face allows leakage that will eventually

cause the valve to burn.

A BIT OF HISTORY

As recently as the mid-1980s, it was not uncommon for engines to require valve reconditioning

as early as 60,000 or 75,000 miles. Now due to advances in materials and machining, most of

today’s engines can run at least 150,000 miles before requiring valve service.

Head Gasket Damage

When a head gasket leaks, it can present a whole host of different symptoms. In the

context of combustion chamber sealing, a failure usually results in a leak between two

adjoining cylinders. This will lower the compression and combustion of both cylinders

significantly. This will cause rough running and a lack of power. Combustion gases can

also leak out into the cooling system. This can cause the cooling system pressure cap

to release pressure and coolant. The most common symptom of a blown head gasket is

coolant leaking into the combustion chamber. Another common symptom of head gasket failure is the presence of coolant in the oil. The oil dipstick will show signs of coolant

mixing with the oil, and it will look foamy and brownish, like a coffee milkshake. In these

situations, a complete engine rebuild may be required. This burning coolant causes clouds

of white, sweet-smelling exhaust to exit the tailpipe (Figure 5-9).

There is a significant difference in cost, labor, and technique, depending on what

problems exist with combustion chamber sealing. It will be your job to recognize the possible causes of low performance, in order to offer the customer responsible repair options

with a realistic estimate.

58111_ch05_hr_105-117.indd 110 2/13/17

xii

256 Chapter 13

oil bearing clearances fall within the range of 0.0008 inch (0.0203 mm) to 0.002 inch

(0.0508 mm). These are just typical clearances; always check the manufacturer’s specifications

for the engine you are working on.

Bearings are a wear item. They are designed to wear and protect the crankshaft or

camshaft. They do wear out after high mileage and exposure to contaminated oil. When the

engine is disassembled for repairs, it is customary to replace the main, rod, and cam bearings.

When fitting new bearings, you will have to check the clearance to ensure that it is

within the specified range. We will discuss this procedure in Chapter 13 of the Shop

Manual.

Undersize and Oversize Bearings

When a crankshaft is worn lightly and polished to be usable, bearings that are 0.001 and

0.002 inch undersize are often available. If the crankshaft has been ground to repair serious

journal wear, undersize bearings

0.010, 0.020, and 0.030 inch undersize. Metric undersized bearings may include 0.050,

can be fitted. These bearings are generally available in