How Engines Work
This chapter is an overview of the entire engine and its system components before you begin study ing each individual system in detail.
Almost all automotive engines used in passenger cars and trucks today operate on the 4-stroke prin ciple. All four of the cycles are described and ex- plained with illustrations for each. .
The theory of combustion is a necessary pnnciple to grasp if you want to understa d how n engine works. Here, the theory is detailed to m clude getting air into the engine via the carburetor, heating the mixture, the timing of the valves to let air and fuel in, and exhaust gases out.
More basics are covered-cylinder numbering,firing order, and engine construction.
Then the chapter goes into the component sys tems. The cooling system is necessary to dissipate the tremendous heat built up during the combus tion process. The valvetrain is covered in a section which explains camshaft, valves, tappets, valve springs and valve action.
Next, you’ll find a discussion of piston construction, piston rings and piston pins. The crank shaft is the very heart of the engine. The cra k components are discussed, including the crank It self, vibration dampers, the flywheel, bearings and more.
There are also separate sections in this chapter on the Corvair air-cooled engine and also qmte extensive definitions of terms.
Engine Valve System
Beginning with this chapter the Auto Engines and Electrical Systems textbook begins to delve in detail into each engine system.
Here, you start at the beginning. What are the valve system parts? Discussions on valve operating conditions and valve clearances are next followed by an extensive section on causes of valve troubles such as leakage, high temperature, seats, and heat caused problems.
Valve system service makes up the rest of the chapter. There are complete instructions on how to check compression, how to use a compression gauge, how to free stuck valves and how to adj st valve lash, plus complete rocker arm serVIce information.
The next part of the chapter explains what is involved with, and how to do, a typical valve job. This is effectively detailed and includes the fol lowing: removing cylinder head, replacing valves, cleaning carbon deposits, valve inspection, measur ing valve-stem-to-valve guide clearance, reaming valve guides, replacing valve guides, replacing valve springs, grinding valves, servicing valve seat inserts, and servicing hydraulic lifters.
You’ll also find a special section on modifyingvalve gear for high performance.
The second large section in this chapter covers timing gear, timing chain, belt and camshaft. .
First is a discussion of the theory of valve tim ing. Then each component that affects valve timing is discussed individually including the tim ing chain or belt, camshaft thrust plate, cam gears or sprocket and crank gear or sprocket.
The balance of the chapter covers the servicing of these components. There are sections covering the replacement of timing gears, timing chains and sprockets, camshaft replacement and cam bearing
replacement. There’s a special section on high per formance camshafts and related components, too.
Engine Piston System
The piston system involves all those parts which transmit the power of combustion to the flywheel. In this chapter, you’ll learn the system components and their servicing.
The first section of the chapter discusses how to determine cylinder bore wear and distorted cylin der bores in a block. Also discussed are other piston-related problems such as .piston ring. wea , piston slap, improperly seated rmgs, excessive oil consumption, and oil loss via various forms of leakage.
The second section discusses piston system service. Here you’ll find the proper method of check ing for external and internal oil loss, how to inspect a cylinder block, how to repair cracked blocks, how to disassemble an engine to perform a ring job, the proper use of the reamer, how to choose proper replacement rings, proper removal and re placement of pistons and rings, and the use of the ring compressor.
In addition to piston rings, you’ll find a complete section on pistons themselves-how to in spect, how to clean, how to check piston skirts for collapse.
The third large section in this chapter deals with cylinder bore service. You11 learn how to check cylinder bores, and how to recognize vari ous conditions such as too much or too little taper, out-of-round bores, wavy bores, etc. Also here is a discussion of various tools used to service cylinder bores. There are three methods commonly used the dial gauge, the inside micrometer, and the telescope gauge. Also covered are major machine tools used in refurbishing cylinder bores such as the glaze buster, flexible hone, rigid hone, and boring bars. You’ll also find a section devoted to reboring of cylinder blocks. The section explains when to bore, how much, and the use of the boring bar. There is also information covering the fitting of cylinder sleeves or liners when reboring isn’t practical plus how to set up a block for high performance use.
The fourth major section in this chapter covers piston pin and connecting rod service. Here, you’ll find a discussion of piston pin sizes and how to check whether piston pins are too loose or too tight.
Moving onto connecting rods, the chapter dis cusses how to remove and replace rod bushings, how to hone piston holes, how to check rod align ment and assemble pistons and connecting rods.
Crankshaft and Bearings
Bearings are covered first. Main and rod bear ings are identified and discussed. Then the c apter turns to the servicing of crankshafts and beanngs.
Oil leakage causing low oil pressure is one of the most common problems found in this part of the engine and there’s a discussion here on how to de tect bearing oil leaks. Other bearing troubles dis cussed include binding, out-of-round bearings and knocks.
Before checking bearings for wear, the crank shaft journals should be inspected for surface smoothness, nicks, and for out-of-round and taper. There is a complete discussion on how this can be accomplished, including procedures showing the use of micrometers.
There are three methods of checking bearing clearances-the shim method, Plastigage method and the micrometer method. You’ll find all three methods discussed in detail here.
Installing bearings requires specific techniques.
So this chapter covers complete installation techniques for both rod and main bearings.A complete crankshaft service requires removal of the crank. Polishing, grinding and other service procedures are discussed here including the im portant check for straightness.
Also included is a discussion on servicing :By wheels and preparing crankshafts for high per formance use.
Engine Oiling Systems
The many parts that make up the automobile engine are either tightly fastened together or move against one another. If they move against one an other, friction becomes a concern and therefore lubrication to keep wear to a minimum and to provide for smooth operation is required.
This chapter delves into the lubrication of the engine, starting with basics. Characteristics of en gine oil, what oils do in an engine, how they work, and their classifications are covered.
How an engine is lubricated and the components that make up the oiling system are covered,unit by unit.
The oiling system service information starts right at the basics too, with how to check the oil level in an engine. Also covered are causes of ex cessive oil consumption, oil changing intervals,
how to change oil, checking for oil leaks, high or low oil pressure and what it means. Then down into the rest of the oiling system: the oil pan, and how to replace it, oil screens, and removing and replacing oil pumps. Oil filters and their workings are explained, too, as are the crankcase ventilation and PCV systems.
Emission Control Systems
Since 1968, emission control systems have been mandated by federal law to be on all new cars sold in this country. This chapter takes you system by system and component by component through the oftentimes complex network of emission con trols used on cars since 1968.
The early systems such as the air pump and electric assist choke are covered first. Other early systems include engine modification systems em ployed by all four of the major U.S. manufacturers.
Then the chapter turns to more modem systems of emission control such as exhaust gas recircula tion, catalytic converters, controlled combustion systems, various ignition spark retard devices and also delay vacuum controlled valves that retard distributor advance.
Next, there is a detailed discussion on evaporative emission controls including both the carbon storage type and the crankcase storage type.
Diesel Engine
As gasoline has become more scarce, and as emission controls have gotten more stringent, the diesel engine has been used more extensively than ever as an automotive powerplant.
This chapter is a detailed explanation of how diesel engines work and how they differ from conventional gasoline engines. There is also a dis cussion of the characteristics of diesel combustion.
As the diesel fuel system is the most complex part of the diesel engine, the fuel system gets the most coverage here. You’ll find information that includes fuel supply units, injection, governors, distributor type systems, and the wobble plate pump system.
Also included is a discussion of recent engineer ing developments in the diesel engine field includ ing Mercedes-Benz’s 5-cylinder diesel engine and General Motors’ Oldsmobile 350 V8 diesel.
The Wankel and How It Works
The Wankel rotary engine is a complete depar
ture from ordinary internal combustion engine design. Despite the differences of design, the op eration of the rotary engine is quite easy to under stand.
This chapter takes you step by step through the Wankel rotary.
A brief history of the development of the engine is discussed and the tremendous performance po tential of the rotary engine is touched upon.
Major engine components are discussed and compared to the equivalent unit in a piston engine, followed by the combustion process in the rotary engine. And here is where most of the similarities and differences occur between a rotary and piston engine.
The Turbine and How It Works
In its basic concept, the turbine engine is the simplest of all engine designs. Yet, because the turbine hasn’t been used in production automo biles, most students of automotive technology feel that they have to be Aeronautical Engineers to understand this complex mystery surrounding the turbine engine.
Not so, as this chapter quickly proves. The chapter leads off with an explanation of exactly how the turbine engine works. It then covers the fuel system, the burner and the ignition system separately.
Also included is a discussion of the possible future uses of turbine engines and their perfonnance characteristics.
Cooling System
The purpose of the cooling system is to preyent temperatures of cylinders, pistons, valves and oth er engine parts from rising high enough to destroy the parts or the oil which lubricates them.
The cooling system chapter explains how this is accomplished. Each component’s function in the system is described. Components covered include the water pump, fan, radiator, drain cocks and plugs, radiator cap, thermostat, and hoses.
There is a discussion of the theory of water physics which explains what happens when water freezes and boils and how anti-freezes alter the chemistry of the water solution, changing the freezing and boiling points.
Cooling system damage is discussed to help in spotting damage from overheating, overcooling, corrosion and other conditions.
Preventive maintenance is as important as repair. So here you’ll fiud a section devoted to that subject. Proper water level, leakage (both internal and external), proper selection and maintenance of thermostats, fan belts and radiator caps are all covered.
The third part of the chapter covers trouble shooting-how to test for such conditions as frozen coolant, overheating, foaming, air suction, combus tion leakage, improperly functioning thermostat, improperly functioning pressure cap, improperly functioning temperature gauge or warning light, and radiator clogging.
The fourth part of the chapter covers cooling system service operations-how to clean a system, how to :flush it out, how to test and add anti-freeze, how to inspect and replace hoses, how to inspect and replace belts, how to service the water pump and how to remove and service the radiator itself.
Fuel System
Feeding the engine is the fuel system-one of the simplest, yet most complex, systems on an au tomobile. The chapter starts with the basics and explains the components of the fuel system and the function of each. Fuel tanks, filters, pumps and lines, air cleaner, carburetor, intake manifold,
-·exhaust system, even fuel gauges are covered here. Also note that fuel injection is covered in the next chapter.
Once you know the components, you should know how an engine uses them to transport fuel which bums and produces power. So the next part of the chapter covers the theory of fuels and how they produce power. Such topics as combustion, pressure detonation and octane rating are covered.
The physics of carburetion is a section that stays with theory but zeroes in on the actual air-fuel mixture as it proceeds through the carburetor. This section discusses vaporization, atmospheric pres sure, vacuum and heat.
The actual carburetor is next . And here you’ll get a thorough understanding of how this most important component works. The text explains the float system, throttle valve, idle and low speed
system, power system, accelerator system, and choke. There’s also a discussion of venturi action and how it affects carburetion principl es plus an explanation of the concept of the balanced car buretor that handles all types of loads.
Also in the chapter is a detailed look at the repair and servicing of the most common carbu retors found in the field-Carter, Holley, Rochester and Stromberg.
Another section is devoted to the fuel system service. Here you11 find information on how to maintain the air cleaner, carburetor, fuel lines, fuel filter, fuel pump, intake manifold and exhaust
·.system in top opera:ting condition.
However, should trouble develop, you have to learn how to spot it. The troubleshooting section that follows explains how to spot various fuel sys tem troubles including an inoperative choke, water in the fuel system, a clogged fuel tank or pipe, fuel pump failure, vapor lock, and leaks. Other troubles covered include diagnosing an engine that won’t idle or start, an engine that loses power, and ex cessive fuel consumption.
The next major section covers carburetor service.
There is overhaul information on most commonly used carburetors. Carter, Holley, Rochester and even Stromberg models are covered.
The last section covers fuel pump service-test ing, overhauling, and diagnosing troubles. There is quite an extensive discussion of high perform ance fuel systems and their setup.
Fuel Injection
Although it’s really part of a car’s fuel system, a fuel injection unit is so different from conven tional carburetion that a separate chapter was necessary to accurately cover the subject.
First, a brief history of fuel injection and its automotive uses is given. Then a separate section for each type of unit details information on com ponents, their function and the overall operation of each system.
Generally, fuel injection units can be divided into two groups-mechanical and electronic. Both types are covered here.
The separate sections include the Rochester unit used on older General Motors cars, the Bendix electronic type and three Bosch systems.
The Bosch systems are the older D-J etronic, the newer L-Jetronic, both of which are electronically controlled units, and the mechanically controlled K-Jetronic continuous system.
Electricity
If electricity seems more mysterious than some of our more prosaic tools like hammers and pliers, it is mainly because electricity is invisible. There is no way of seeing an electric current :flow throu gh a wire.
This chapter pulls the wraps off the mystery. It covers the theory of electricity from a practical viewpoint , looking briefly into atomic theory and electrons, but then moves quickly onto Ohm’s law,
volts, amps, types of circuits, electrical measure ments and electrical conductors.
Magnetism
Most of the lectrical units in a car employ not only electricity but also magnetism (produced by electricity) to make them work. The list of elec tromagnetic units includes the starting motor (and other electric motors), ignition coil, hom, hom relay, solenoids, cutout relay, current regulator, voltage regulator (unless it’s a new electronic type), etc.
This chapter explains the theory of magnetism right from the basics-magnetic fields, moving electrons, opposite poles, etc. Then, the next moves on to cover how an electric generator and electric motors work.
Electrical System
Once you know the basics of electricity and magnetism, it’s time to apply that knowledge to the workings of an automobile. With this chapter, we move away from basic theory and into the realm of practical knowledge.
Starting right in with how to read a wiring diagram, the chapter takes you step by step through the various circuits that make up an au tomobile’s electrical system. Covered are the start ing circuit, charging circuit, ignition circuit, hom circuit, windshield wiper circuit, instrument cir cuit and lighting circuit.
The chapter then discusses electrical system service. Such topics as electrical wiring, cable gauge, ignition cable, replacing cables, terminal connections, and selecting proper cable are all covered.
Ignition System
The purpose of the ignition system is to supply sparks across the electrodes of the spark plugs to ignite the air-fuel mixture in the cylinders.
This chapter first explains the components of the ignition system and their function. The igni ti n coil, condenser, spark plugs, and distributor are covered.
The distributor is detailed separately and the principles of centrifugal and vacuum spark advance are discussed.
The service section begins with a troubleshoot ing guide that helps pinpoint such troubles as a bad condenser, grease or oil in the distributor, a
loose connection, incorrect breaker point gap, worn distributor shaft bushings, worn breaker arm pivot bushings, improper breaker spring tension, hard starting, and miss.
Causes of ignition coil failure are discussed as is the importance of correct coil polarity. Instruc tions for testing coils are included.
In order to help you judge the condition of spark plugs accurately, there is a section covering analysis of plug conditions plus information on gaskets, cleaning, adjusting gaps and proper in stallation techniques.
Condensers and breaker points are covered sep arately in the service section. Causes of condenser breakdown are given as is information on how to read breaker points.
Distributor inspection procedure is explained including methods of testing centrifugal and vac uum advance and testing the condenser circuit.
The balance of the chapter consists of detailed overhaul information for Delco-Remy, Ford, Hol ley, Prestolite, and Chrysler distributors. Each make is covered in a separate section.
Transistorized and Electronic Ignition Systems
Both pure electronic and also transistorized systems are covered in this chapter.
Since transistorized systems were in use earlier, they’re covered first. The first section of this chapter explains what a transistor is and how it is applied to an ignition system. Then, specific systems are covered including the Delco-Remy and Ford systems. The operation of each system is described as are the service recommendations and troubleshooting procedures for each.
The pure electronic systems are in the second part of this chapter. A brief history of electronic ignition systems is followed by a discussion of the advantages of an electronic system over a con ventional breaker point ignition system.
Then each electronic system’s theory of operation is covered. Included in the discussion are the Chrysler, Ford, General Motors and Prestolite sys tems plus the systems currently being used on im ported cars.
You’ll also find a discussion of General Motors’ Micro-Processed Sensing and Automatic Regula tion ( MISAR) system.
Generators and Regulators
In the early days of automobiles, there weren’t many electrical devices used and the need for power generation was small. As the need for electrical power grew, su did the importance of the generator. Although no longer in use, this book would not be complete if we didn’t cover DC gen erators because there are probably still several million cars on the road using an older style DC
generator.
This chapter first explains generator construction and how a generator actually produces power There is also a section on generator service in cluding rebuilding information.
A regulator is designed for one purpose only to regulate or control the charging rate in the generator-battery circuit.
The second part of the chapter covers regulators from their construction to their operation. Following the theory discussion, there is informa tion on how to replace regulators and also how to test specific models made by Ford, Prestolite, Bosch and Delco-Remy.
Separate review questions for generators and regulators appear at the end of the chapter.
Alternator Systems
As the electrical demands of the modern auto mobile became too much for the old style DC generator, automobiles were equipped with AC generators, or alternators. Previously, alternators were used only on city delivery trucks, heavy duty vehicles, buses and other vehicles where the de mand on the electrical system was extreme.
This chapter first covers the differences between an alternator and generator, then details the con struction of the alternator. There is also a complete discussion on how the alternator functions to pro duce power.
An explanation of how the alternator changes AC current to DC so that the other parts of the electrical system can use the power is also covered here.
The second part of the chapter covers alternator service. The Chrysler, Delco-Remy, Ford, Leece Neville, Motorola, and Prestolite sys·tems are all described, their system components detailed, then covered completely for service and overhaul. There is a very extensive testing section for each brand of alternator.
Alternator Systems
As the electrical demands of the modern auto mobile became too much for the old style DC generator, automobiles were equipped with AC generators, or alternators. Previously, alternators were used only on city delivery trucks, heavy duty vehicles, buses and other vehicles where the de mand on the electrical system was extreme.
This chapter first covers the differences between an alternator and generator, then details the con struction of the alternator. There is also a complete discussion on how the alternator functions to pro duce power.
An explanation of how the alternator changes AC current to DC so that the other parts of the electrical system can use the power is also covered here.
The second part of the chapter covers alternator service. The Chrysler, Delco-Remy, Ford, Leece Neville, Motorola, and Prestolite sys·tems are all described, their system components detailed, then covered completely for service and overhaul. There is a very extensive testing section for each brand of alternator.
Included here are the Chrysler reduction gear type, the Chrysler direct drive type, Delco-Remy type, Ford starter with integral positive engage ,ment drive, Ford type with Folo-Thru drive and
all Prestolite starters.
The end of this chapter contains a guide to starter motor problems.
Starting Switches
Magnetic and solenoid switches are designed to perform mechanical jobs electromagnetically such as closing a heavy circuit or shifting the starter drive pinion with the engine flywheel ring gear for cranking.
There are several types in common usage and this chapter covers them all-magnetic and sole noid types. There are separate sections for the Carter vacuum switch and the Stromberg vacuum switch.
The balance of the chapter consists of starter switch service information including checking switch operation.
The Storage Battery
The first question is, what does a battery do? That’s where this chapter starts. You’ll also find complete information on how a battery works, how a battery is constructed and how a battery’s power capacity is determined.
There is a detailed troubleshooting guide to various battery troubles including sulphation, in sufficient electrolyte, overheating, overcharging, buckled plates, freezing, corrosion, and vibration.
The theory and the how to of hydrometer test ing is explained. Other service information in cludes the proper way to add water, how to test for electrical capacity, the proper method of re moving and installing a battery, and proper charg ing techniques.
Dash Gauges
All vehicles have at least four gauges or indi cator lights to tell the driver how various systems are functioning. This chapter describes the con struction and operation of the commonly used automotive gauges-fuel level, oil pressure, coolant temperature, and ammeter.
There is also servicing information for these gauges plus information on dash indicator lights, speedometers, electric clocks and other accessories.