Engine Repair Fundamentals - Self Study

8/6/2019 Engine Repair Fundamentals - Self Study

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enginerepai

enginrepai

fundamental

self-stud

COURSE CODE: 32S01ORDER NUMBER: FCS-13031-R

Ford Customer Service DivisionTechnical Training


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IMPORTANT SAFETY NOTICE

Appropriate service methods and proper repair procedures are essential for the safe, reliable operation of all motor vehicles,as well as the personal safety of the individual doing the work. This manual provides general directions for accomplishingservice and repair work with tested, effective techniques. Following them will help assure reliability.

There are numerous variations in procedures, techniques, tools and parts for servicing vehicles, as well as in the skill of theindividual doing the work. This manual cannot possibly anticipate all such variations and provide advice or cautions as toeach. Accordingly, anyone who departs from instructions provided in this manual must first establish that he compromises

neither his personal safety nor the vehicle integrity by his choice of methods, tools or parts.

As you read through the procedures, you will come across NOTES, CAUTIONS, and WARNINGS. Each one is there for aspecific purpose. NOTES give you added information that will help you to complete a particular procedure. CAUTIONS aregiven to prevent you from making an error that could damage the vehicle. WARNINGS remind you to be especially carefulin those areas where carelessness can cause personal injury. The following list contains some general WARNINGS thatyou should follow when you work on a vehicle.

Always wear safety glasses for eye protection.

Use safety stands whenever a procedure requires you tobe under the vehicle.

Be sure that the ignition switch is always in the OFFposition, unless otherwise required by the procedure.

Set the parking brake when working on the vehicle. If youhave an automatic transmission, set it in PARK unlessinstructed otherwise for a specific service operation. Ifyou have a manual transmission it should be in RE-VERSE (engine OFF) or NEUTRAL (engine ON) unlessinstructed otherwise for a specific service operation.

Operate the engine only in a well-ventilated area to avoidthe danger of carbon monoxide.

Keep yourself and your clothing away from moving partswhen the engine is running, especially the fan and belts.

To prevent serious burns, avoid contact with hot metalparts such as the radiator, exhaust manifold, tail pipe,catalytic converter and muffler.

Do not smoke while working on the vehicle.

To avoid injury, always remove rings, watches, loosehanging jewelry, and loose clothing before beginning to

work on a vehicle. Tie long hair securely behind yourhead.

Keep hands and other objects clear of the radiator fanblades. Electric cooling fans can start to operate at anytime by an increase in underhood temperatures, eventhough the ignition is in the OFF position. Therefore, careshould be taken to ensure that the electric cooling fan iscompletely disconnected when working under the hood.

The recommendations and suggestions contained in this manual are made to assist the dealer in improving his dealership partsand/or service department operations. These recommendations and suggestions do not supersede or override the provisions othe Warranty and Policy Manual, and in any cases where there may be a conflict, the provisions of the Warranty and Policy Manuashall govern.

The descriptions, testing procedures, and specifications in this handbook were in effect at the time the handbook wasapproved for printing. Ford Motor Company reserves the right to discontinue models at any time, or change specifications,design, or testing procedures without notice and without incurring obligation. Any reference to brand names in this manualis intended merely as an example of the types of tools, lubricants, materials, etc. recommended for use. Equivalents, ifavailable, may be used. The right is reserved to make changes at any time without notice.

WARNING: MANY BRAKE LININGS CONTAIN ASBESTOS FIBERS. WHEN WORKING ON BRAKE COMPONENTS, AVOIDBREATHING THE DUST. BREATHING THE ASBESTOS DUST CAN CAUSE ASBESTOSIS AND CANCER.

Breathing asbestos dust is harmful to your health.

Dust and dirt present on car wheel brake and clutch assemblies may contain asbestos fibers that are hazardous to your healthwhen made airborne by cleaning with compressed air or by dry brushing.

Wheel brake assemblies and clutch facings should be cleaned using a vacuum cleaner recommended for use with asbestos fibersDust and dirt should be disposed of in a manner that prevents dust exposure, such as sealed bags. The bag must be labeled peOSHA instructions and the trash hauler notified as to the contents of the bag.

If a vacuum bag suitable for asbestos is not available, cleaning should be done wet. If dust generation is still possible, techniciansshould wear government approved toxic dust purifying respirators.

OSHA requires areas where asbestos dust generation is possible to be isolated and posted with warning signs. Only techniciansconcerned with performing brake or clutch service should be present in the area.

Copyright 2000 Ford Motor Company Produced and Coordinated byTechnical Support OperationsFord Customer Service Division

March, 2000


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5. Provide me with a clear and thorough

explanation of the service performed.

6. Call me within a reasonable amount oftime after my service visit to ensure thatI'm completely satisfied.

7. Be responsive to questions or concernsI bring to your attention.

1. Make it convenient to have my

vehicle serviced at your dealership.

2. The Service Advisor shoulddemonstrate a genuine concern formy service needs.

3. Fix it right the first time.

4. Complete servicing my vehicle in atimely and professional manner.

Expectation 3Fix It Right The First Time, on Time.

Both service advisors and technicians areimportant players when it comes to Expectation#3.

Why

Customers tell us Fixing It Right The First Time, on Time is one of the reasons theywould decide to return to a dealer to buy a vehicle and get their vehicles serviced.

Technician Training

It is our goal to help the technician acquire all of the skills and knowledge necessary toFix It Right The First Time, on Time. We refer to this as competency.

Technicians Role

Acquire the skills and knowledge for competency in your specialty via:

STST New Model

Self Study Self Study

FordStar Broadcasts FordStar Broadcasts

Ford Multimedia Training (FMT) Instructor Led Instructor Led

The Benefits

The successful implementation of expectations means:

Satisfied customers Repeat vehicle sales

Repeat service sales Recognition that Ford and Lincoln/Mercury technicians are the Best in the

Business

CUSTOMER EXPECTATIONS

Customer Expectations: Service


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TABLE OF CONTENTS

Engine Repair Fundamentals March, 2000 i

INTRODUCTION ............................................................................................................................ Intro-1Introduction ............................................................................................................................... Intro-1

Engine Repair Curriculum ......................................................................................................... Intro-2

Engine Repair Curriculum Path................................................................................................. Intro-3

Course Description and Format ................................................................................................. Intro-4

LESSON 1: ENGINE FUNDAMENTALS ......................................................................................... 1-1

Objectives ........................................................................................................................................ 1-1Contents ........................................................................................................................................... 1-1

Engine Fundamentals ...................................................................................................................... 1-2

Four-Stroke Operation ..................................................................................................................... 1-3

Intake Air System .......................................................................................................................... 1-10

Fuel System ................................................................................................................................... 1-13

Ignition System.............................................................................................................................. 1-14

Exhaust System ............................................................................................................................. 1-15

Exhaust Gas Recirculation (EGR) System .................................................................................... 1-16

Cooling System ............................................................................................................................. 1-17

Lubrication System............................................................................................................. ........... 1-20

Positive Crankcase Ventilation (PCV) System .............................................................................. 1-23Review Questions .......................................................................................................................... 1-25

LESSON 2: OIL AND LUBRICANTS ............................................................................................... 2-1Objectives ........................................................................................................................................ 2-1

Contents ........................................................................................................................................... 2-1

Primary Purposes of Engine Oil ...................................................................................................... 2-2

Oil Properties ................................................................................................................................... 2-8

Rating Oils ..................................................................................................................................... 2-11

Additives ........................................................................................................................................ 2-12

Engine Damage.............................................................................................................................. 2-14

Review Questions .......................................................................................................................... 2-17

LESSON 3: FUELS ............................................................................................................................. 3-1Objectives ........................................................................................................................................ 3-1

Contents ........................................................................................................................................... 3-1

Types of Fuels .................................................................................................................................. 3-2

Gasoline Additives ........................................................................................................................... 3-4

Additives That Do Not Improve Performance ................................................................................. 3-5

Alternative Fuels.............................................................................................................................. 3-9

Review Questions .......................................................................................................................... 3-11


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TABLE OF CONTENTS

ii March, 2000 Engine Repair Fundamentals

LESSON 4: COOLANT ...................................................................................................................... 4-1Objectives ........................................................................................................................................ 4-1

Contents ........................................................................................................................................... 4-1

Purpose of Coolant .......................................................................................................................... 4-2

Types of Coolant.............................................................................................................................. 4-3

Review Questions ............................................................................................................................ 4-9

LESSON 5: SEALANTS .................................................................................................................... 5-1Objectives ........................................................................................................................................ 5-1

Contents ........................................................................................................................................... 5-1

Sealants ............................................................................................................................................ 5-2

Review Questions ............................................................................................................................ 5-7

ANSWERS TO REVIEW QUESTIONSLesson 1 ............................................................................................................................... Answers-1

Lesson 2 ............................................................................................................................... Answers-3

Lesson 3 ............................................................................................................................... Answers-5

Lesson 4 ............................................................................................................................... Answers-7

Lesson 5 ............................................................................................................................... Answers-9


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INTRODUCTION

Engine Repair Fundamentals March, 2000 Intro-1

INTRODUCTION

The Engine Fundamentals self-study is the first course of the Engine Repair Curriculum. Since this course sets

the building blocks for the other courses, it is important that it be completed first. It is also important that all

prerequisite courses be completed prior to taking this self-study, as this will lead to a better understanding of the

material presented.

This course has two main goals. The first goal is to introduce you to the basic engine theory of operation. Thesecond goal is to provide an understanding of the symptom-to-system-to-component-to-cause diagnostic process.

As you learn new information, try to relate the new knowledge to the basic engine systems as a whole. Think

about the cause-and-effect relationships between the subsystems and components. Understanding the cause-and-

effect relationships will help you in diagnosis. This course will include information related to basic engine

systems. Some of the topics that will be covered in this course include the following:

l Four-stroke operation

l Intake air system

l Fuel system

l Ignition system

l Exhaust system

l Exhaust gas recirculation (EGR) system

l Cooling system

Although you may be familiar with some of these topics, it is essential that you, as a professional engine

technician, have a thorough understanding and mastery of this information. You will find that mastery learning

is necessary to diagnose and service the latest engine systems.


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INTRODUCTION

Intro-2 March, 2000 Engine Repair Fundamentals

ENGINE REPAIR CURRICULUM

Each course found in the Engine Repair Curriculum is one of the following types:

l Self-study This type of course is a self-paced program. The technician is responsible for learning the material

on his or her own. The training material consists of a reference book and an accompanying videotape. The

videotape is designed to support the material in the reference book and should not be used on its own.

l Ford Multimedia Training (FMT) This type of course is also self-paced. The multimedia course allows the

technician to interact with the training materials. The multimedia course allows the technician to utilize the

knowledge attained in the self-study course. The FMT concentrates on relationships, such as the cause-and-

effect relationships between symptoms and components.

l Classroom The classroom course allows for practical, real-world application of skills and knowledge learned

in the other courses.

There are five courses in the Basic Engine Curriculum. Please refer to the Engine Repair Curriculum Path that

follows.

Course Codes

These courses may be found in the STARS planner using the following course codes:

Engine Performance

l Engine Repair Fundamentals Self-Study .................................................................. Course code: 32S01S0

l Automotive Measuring Tools FMT .......................................................................... Course code: 32S02M0

l Base Engine Operation and Diagnosis ......................................................................... Course code: 32S03M0

l Engine Repair Classroom.......................................................................................... Course code: 32S05T0

l Servicing New Engine Designs Fordstar .................................................................. Course code: 32S06F0

Why Training?

1. Customers bring vehicles to the dealership because they want the best service possible. They believe that no

other technician besides you, a Ford trained technician, could know their vehicle better.

2. Customers expect a dealership to Fix It Right The First Time, On Time.

So, how do you live up to the customers expectations? The answer is continuous training. Training allows you to

gain efficiency. Efficiency makes you an asset to the customer, the dealer, and yourself. Training promotes job

security and allows you to learn the latest and greatest technology and service procedures.


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INTRODUCTION

Engine Repair Fundamentals March, 2000 Intro-3

Engine RepairFundamentals

SS

1

AutomotiveMeasuring Tools

FMT

2

ENGINE REPAIRCURRICULUM PATH

Prerequisites

NVH (Classroom)

Basic Electrical Part 1 (Self Study)

Basic Electrical Part 2 (FMT)

Basic Electrical Part 3 (Classroom)

Electronics Part 1 (Self Study)

Electronics Part 2 (FMT)

Electronics Part 3 (Classroom)

Base EngineOperation and Diagnosis

FMT

Legend

1 = Self Study (SS)

2 = Ford Multimedia Training (FMT)

3 = FORDSTAR

4 = Instructor Led Classroom

2

Servicing NewEngine Designs

FORDSTAR

EngineRepair

Classroom

4

3

ENGINE REPAIR CURRICULUM PATH


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INTRODUCTION

Intro-4 March, 2000 Engine Repair Fundamentals

COURSE DESCRIPTION AND FORMAT

Course Description for Self-Study Learners

This Student Reference Book is designed for use as part of a self-study training course, which means you can

allow yourself as much time as you need to learn the information in each section. A videotape has been developed

to accompany this book. The videotape provides information that can best be presented through visual means.

Lesson Review Questions are provided throughout this book to help evaluate your individual learning needs.

Answers to the Lesson Review Questions are provided with page references to help you determine your strengths

and weaknesses. If you have difficulty answering certain questions, review the material until you feel confident

that you understand the information.

Take as much time as you need to master the material. You may not answer the questions 100% correctly the first

time around. With study, you will quickly master those areas with which you may have difficulty.

Evaluation Strategy

The final evaluation questions for this self-study course are also on Base Engine Operation and Diagnosis FMT

CD-ROM. You must pass this test for the Engine Repair Fundamentals Self-Study before you can begin the FMT

course.


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LESSON 1: ENGINE FUNDAMENTALS

Engine Repair Fundamentals March, 2000 1-1

OBJECTIVES

l Describe the Four-Stroke Theory.

l Describe the Intake Air System.

l Describe the Fuel System.

l Describe the Ignition System.

l Describe the Exhaust System.

l Describe the Exhaust Gas Recirculation System.

l Describe the Cooling System.

l Describe the Lubrication System.

l Describe the Positive Crankcase Ventilation

System.

CONTENTS

l Engine Fundamentals

l Four-Stroke Operation

l Intake Air System

l Fuel System

l Ignition System

l Exhaust System

l Exhaust Gas Recirculation (EGR) System

l Cooling System

l Lubrication System

l Positive Crankcase Ventilation (PCV) System

l Review Questions


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1-2 March, 2000 Engine Repair Fundamentals

ENGINE FUNDAMENTALS

The engines used in all Ford Motor Company

passenger vehicles are four-stroke internal

combustion engines. Internal combustion means the

burning of the fuel used to power the vehicle takes

place inside the engine.

Although todays engines are far more efficient in

terms of fuel economy, cleaner exhaust emissions,

and increased durability, they still use the same basic

principles of operation as the original four-stroke

engines.

Cylinders are inserted or cast into the engine block.

The cylinder houses a piston. The piston is connected

to a crankshaft by a connecting rod. The up and down

movement of the piston is converted into rotarymotion by the crankshaft. The crankshaft is used to

transfer power to the drivetrain.

FS020-C

1

2

34

Item Description

1 Cylinder

2 Piston

3 Connecting Rod4 Crankshaft


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FOUR-STROKE OPERATION

Item Description

1 Intake Stroke

2 Compression Stroke

Item Description

3 Power Stroke

4 Exhaust Stroke

The four-stroke system of operation consists of an intake stroke, compression stroke, power stoke, and exhaust

stroke. One stroke is counted each time the piston moves the entire length of the cylinder. The term four-stroke

engine is used because the piston moves up or down the cylinder four times in one cycle.

RFS001-D

1 2 3 4


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Vacuum

During the intake stroke, the downward movement of

the piston creates a low-pressure area above the

piston, which draws air into the cylinder. At the same

time, atmospheric pressure is trying to force air into

the cylinder. A throttle plate is used at the air intake

of the engine to control the amount of air that is

allowed to enter the engine. While the engine is

idling, the throttle plate is closed. During closed

throttle operation a minimal amount of atmospheric

pressure is allowed to enter the engine. Because a

low-pressure area is created during each cylinders

intake stroke, a pressure differential occurs between

atmospheric pressure and the low pressure within the

engine. The low pressure within the engine is known

as a vacuum. Vacuum is high 43-56 cm Hg(17-22 in. Hg) at idle with the throttle closed.

When the throttle plates are opened, more

atmospheric pressure is allowed into the engine and

the amount of vacuum decreases. At Wide Open

Throttle (WOT) there is very little vacuum in the

intake manifold. Item Description

1 Atmospheric Pressure

2 Low Pressure

3 Closed Throttle

RFS010-C

2

1

3


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Compression Stroke

The second stroke in the four-stroke cycle is the

compression stroke. As the piston passes bottom dead

center (its lowest point of movement) and starts up

again, the compression stroke begins. The intake

valve is closed and the exhaust valve remains closed.

The air/fuel mixture trapped in the cylinder is now

compressed into a very small volume at the top of the

cylinder or Top Dead Center (TDC). As the air/fuel

mixture is compressed the temperature of the mixture

increases dramatically.

The top of the piston and the dome of the cylinder

head form the combustion chamber. The combustion

chamber contains the intake and exhaust valves plus a

spark plug. As the air/fuel mixture is compressed in

the combustion chamber, the mixture is ignited by the

spark plug and the power stroke begins.

Item Description

1 Intake Valve Closed

2 Spark Plug

3 Exhaust Valve Closed

RFS003-B

1

2

3


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Compression Ratio

The difference in volume when the piston is at BDC

(A) and TDC (B) is called the compression ratio.

If the cylinder has nine times the volume at BDC than

at TDC, the compression ratio is 9:1 (nine-to-one).

The air/fuel ratio is compressed so that it burns

completely and delivers the maximum amount

of power.

RFS006-C

BDC

TDC

A B

1

2

3

4

5

6

7

8

9

1

2

3

4

5

6

7

8

9


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Power Stroke

The third stroke in the four-stroke cycle is the power

stroke. The power stroke begins as the air/fuel

mixture, compressed in the combustion chamber, is

ignited by the spark plug. As the spark ignites the air/

fuel mixture a controlled explosion is created within

the combustion chamber. The pressure created from

the combustion causes a rapid increase in the pressure

within the cylinder. This increase in pressure pushes

down on the top of the piston. This burst of energy is

transferred to the crankshaft and is measured as

horsepower and torque.

Item Description


2 Spark Plug

3 Exhaust Valve Closed

RFS004-B

1 2 3


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Exhaust Stroke

The fourth and final stroke in the four-stroke cycle is

the exhaust stroke. The exhaust valve is opened as the

rotation of the crankshaft pushes the piston back up

the cylinder. This forces the burned gases out through

the exhaust port. As the piston reaches top dead

center, the intake valve is opened again and the cycle

repeats itself. The exhaust valve is closed shortly after

the piston begins its downward movement of the

intake stroke.

The engine relies on other systems to ensure that

combustion takes place smoothly and efficiently.

These systems are as follows:

l Intake air system

l Fuel system

l Ignition system

l Exhaust system

l Exhaust gas recirculation (EGR) system

l Cooling system

The following section covers these systems.Item Description


2 Spark Plug

3 Exhaust Valve Open

RFS005-B

1 2 3


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RFS007-C

2

3

1

INTAKE AIR SYSTEM

Item Description

1 Air Cleaner Assembly

2 Intake Air Hose

3 Throttle Body

The intake air system is responsible for controlling the amount of air allowed into the engine.

Air Cleaner

Air is drawn through the air cleaner and intake air tube before entering the engine. The air cleaner filters theincoming air to prevent dirt and other contamination from entering the engine. Dirt particles can cause damage to

internal engine components and drastically reduce engine life.

Another function performed by the air cleaner housing is to reduce or muffle the noise created by incoming air.


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Intake Manifold

Item Description

1 Intake Manifold

2 Throttle Body

The intake manifold is used to direct incoming air into the cylinders. Air enters the engine through the throttle

body and is sent to individual intake runners that direct the air to each cylinder.

During engine design the length of the intake runners can be varied to determine the rpm range where an engine

will best perform. Long narrow intake runners are used to enhance low rpm performance. Short wide-open intake

runners are used to enhance high rpm performance. On some engines both types of runners are used to enhance

overall engine performance.

RFS009-B

1 2


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FUEL SYSTEM

Item Description

1 Fuel Tank

2 Fuel Pump and Pick-up

3 Fuel Filter

Item Description

4 Fuel Injectors

5 Fuel Rails

6 Fuel Injectors

The purpose of the fuel system is to store a quantity of fuel and supply fuel to the cylinders during engine

operation.

The fuel system starts at the fuel tank where fuel is stored. A fuel pump transfers fuel from the bottom of the fuel

tank and through a pick-up/strainer. The fuel then travels through the fuel lines and fuel filter. The fuel filter

prevents contamination of the fuel injectors by removing particulates in the fuel. After passing through the fuel

filter, fuel is sent to a fuel rail that is used to direct fuel to fuel injectors. On many vehicles, excess fuel is

returned to the fuel tank through a return fuel line.

Pressure in the fuel rail is controlled by either regulating the current to the fuel pump or by a fuel pressure

regulator located on the return side of the fuel rail.

Modern Ford Motor Company vehicles use electronic fuel injection that sprays fuel directly into the engines

intake port. Shortly before the intake valve opens to allow the air into the cylinder, a fuel injector sprays a mist of

fuel into the intake port of each cylinder. The air/fuel mixture is drawn into the cylinder when the intake valve

opens.

A Powertrain Control Module (PCM) determines the most effective time and amount of fuel to deliver. At the

correct time, the PCM commands the fuel injector to spray a mist of fuel into the intake port.

6

RFS012-B

5

3

1

2

4


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IGNITION SYSTEM

Item Description

1 Coil Pack

2 Ignition Wires

3 Spark Plug

An ignition system is used to deliver the spark necessary to ignite the air/fuel mixture in the cylinder.

Ignition coils generate the high voltages necessary for the spark to jump the air gap at the spark plug. The primary

side of the coil generates a magnetic field when both power and ground are supplied to the coil. When the ground

circuit is opened a high voltage is induced in the secondary side of the coil. This high voltage is delivered to the

spark plug through spark plug wires that are attached between the secondary side of the ignition coil and the

spark plug. Coil-on-plug systems mount the ignition coils directly above the spark plugs and eliminate the need

for spark plug wires.

A control module controls the electrical current to the ignition coil(s) to turn them on and off. Various inputs are

used by the module to determine precisely when and how long the coil(s) should be turned on or off.

Item Description

4 Crankshaft Position Sensor

5 Control Module

6 Coil-On-Plug

RFS020-A

1 2 3

4

1011

1 2 3

5

6 4


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EXHAUST SYSTEM

Item Description

1 Mufflers

2 Resonators

Item Description

3 Tailpipes

4 Catalytic Converters

The exhaust system directs exhaust gases from the exhaust manifold through the exhaust pipes to the catalytic

converter then through the muffler and out the tailpipe.

Tailpipe Emissions

Emissions are created as a by-product of the combustion process. In perfect conditions, the only emissionscreated from an internal combustion engine would be carbon dioxide (CO2) and water (H2O). Since conditions in

the real world are never perfect, internal combustion engines create harmful emissions such as hydrocarbons

(HC), carbon monoxide (CO), and oxides of nitrogen (NOx).

Several methods are used to control emissions. A fuel control system, ignition system, catalytic converter, and

Exhaust Gas Recirculation (EGR) system work together to keep the engine operating as efficiently as possible.

RFS011-B

1

2

3

4


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EXHAUST GAS RECIRCULATION (EGR) SYSTEM

At high combustion temperatures (above 1,372C [2,500F]), nitrogen and oxygen in a cylinder can chemically

combine to form the harmful emission NOx.

The EGR system recirculates exhaust gases into the combustion chamber under certain conditions.

Since exhaust gas has already combusted, the exhaust gases cannot burn again. Recirculating exhaust gas into the

cylinder displaces some of the normal air/fuel mixture. As a result, EGR slows and cools the combustion process

by several hundred degrees, which reduces NOx formation.

Item Description

1 EGR Valve

2 Exhaust Gas

3 Intake Air

RFS016-B

EGR

TUBE

INTAKE

1

2

3


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COOLING SYSTEM

Item Description

1 Thermostat

2 Pressure Cap

3 Water Pump

Item Description

4 Radiator

5 Coolant Reservoir

6 Heater Core

The cooling system consists of the following components:

l Coolant

l Water Pump

l Cooling Passages and Hoses

l Radiator

l Cooling Fan

l Radiator Pressure Cap

l Radiator Coolant Recovery Reservoir

l Thermostat

RFS014-C

1

2

3

45

6


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The three main purposes of the cooling system are:

l Maintain the desired operating temperature under all conditions

l Allow the engine, on start-up, to reach the desired operating temperature as quickly as possible

l Heat the passenger compartment

The cooling system maintains the desired operating temperature. The cooling system prevents the engine from

overheating and prevents the engine from running too cool.

The desired operating temperature is within a specific range. Too high a temperature results in overheating of

cylinder walls, pistons, cylinder heads, valves and other engine components. Too low a temperature results in

premature component wear, carbon deposits, and poor fuel economy.

All Ford Motor Company gasoline engines are liquid-cooled. This means the engine block, cylinder head and in

some cases the intake manifold have cooling passages. Coolant circulates through the engine and radiator.

Coolant absorbs the heat generated by combustion and friction. Heat transfers from the radiator to the outside air

as the coolant flows through the radiator. Engine coolant flowing through the heater core is used to heat the

passenger compartment.

1. Coolant

Coolant transfers heat from the engine, lubricates the water pump, protects the cooling system from corrosion,

and prevents freezing and boil over. Coolant is a 50/50 mixture of water and green-colored ethylene glycol. A

few Ford applications use orange-colored Organic Acid Technology (OAT), or extended life coolant. Green and

orange coolants are not interchangeable.

The coolant mixture lowers the freezing point and raises the boiling point of the coolant. Additives in the coolant

lubricate the water pump and prevent corrosion of the cooling system components.

2. Water Pump

The water pump circulates coolant through the radiator, heater core, engine block, and cylinder head. A belt on

the Front End Accessory Drive (FEAD) drives the water pump. The FEAD turns a pulley, which is connected to a

shaft that drives the impeller. The impeller is basically a paddle wheel that pushes the coolant from the pump into

the engine block and cylinder head.

3. Cooling Passages and Hoses

The rubber hoses and cooling passages in the engine block and cylinder head (and in some cases in the intake

manifold) allow coolant a path to and from the radiator, heater core, and throughout the engine.

4. Radiator

The radiator is basically a heat exchanger. As the coolant passes through the tubes of the radiator, heat transfers

to the thin fins of metal or aluminum. Heat transfers from the radiator fins to the passing air. The coolant,

now significantly cooler than when it entered the radiator, circulates back into the engine to absorb and remove

more heat.


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5. Cooling Fan

At highway speeds, the radiator has enough airflow across the radiator for effective heat transfer. At lower

speeds, like stop-and-go driving and idle conditions, the radiator does not have enough airflow to effectively

remove heat from the coolant. Under low airflow conditions the cooling fan draws more air across the radiator

fins. Most modern cooling fans are electric and are controlled by the PCM. The cooling fan shroud increases

efficiency and prevents injury.

6. Pressure Cap

The cooling system is a pressurized system. Because the cooling system is a closed system the pressure in the

cooling system rises as temperatures rise. Todays cooling systems are designed to have about 96.5-117.2 kPa

(14-17 psi) of pressure at operating temperature. Cooling system pressure raises the boiling point of the coolant.

A pressure cap is used to maintain correct cooling system pressure. On some vehicles the pressure cap is located

on the radiator. Excessive pressure and coolant will be released to a coolant recovery reservoir.

Other vehicles locate the pressure cap on the coolant recovery reservoir. In these systems, excess pressure is

allowed to escape from the top of the reservoir.

Since the cooling system is pressurized at operating temperature, the radiator cap should never be removed when

the system is hot. The hot coolant may spray from the radiator and cause injury.

7. Radiator Coolant Recovery Reservoir

The coolant recovery reservoir allows for the expansion and contraction of coolant due to temperature

differences. Some systems use a pressurized reservoir requiring a pressure cap. This system will typically have

coolant flow through the recovery reservoir during normal operation.

8. Thermostat

The thermostat ensures that the engine reaches operating temperature as quickly as possible.

The thermostat prevents coolant from entering the radiator as the engine warms up. Preventing the radiator from

removing heat from the coolant reduces the amount of time needed to reach operating temperature. A small

amount of coolant circulates through the water pump bypass, preventing hot spots in the coolant.

When the coolant reaches operating temperature, a temperature-sensitive wax in the thermostat expands, pushing

the valve in the thermostat open. When the thermostat is open coolant flows through the entire cooling system,

including the radiator.


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RFS015-B

1

2

34

5

LUBRICATION SYSTEM

Item Description

1 Oil Passage

2 Oil Passage

3 Oil Filter

Item Description

4 Oil Pan

5 Oil Pump


31/94



The main functions of the lubrication system in an engine are to:

l Reduce friction

l Prevent wear

l Remove heat

l Clean

l Seal

l Prevent corrosion

All moving components in an engine require constant lubrication. Without lubrication, metal to metal contact

quickly destroys the components. Engine oil forms a thin barrier between the metal surfaces, preventing metal to

metal contact.

Parasitic drag is the amount of energy lost in a running engine due to friction between moving parts. If an engine

has a high amount of parasitic drag there is less available energy to perform work. Engine oil reduces parasitic

drag. Reducing the amount of friction between components increases the amount of available energy that can be

used to perform work.

Oil Pan

Several quarts of oil are stored in the oil pan, which is bolted to the bottom of the engine. The oil pan stores

engine oil until the oil is needed in the engine. Heat transfers through the oil pan as the oil waits to be circulated

through the engine.

Oil Pump and Oil Pump Tube and Screen Cover

The oil is drawn in through the oil pump tube and screen cover. The screen cover prevents the oil pump from

ingesting large contaminants. The oil pump pressurizes and circulates the oil through the lubrication system.


32/94



Oil Filter

The oil circulates from the pump to the oil filter, where particles that may cause engine damage are removed from

the oil. Regular replacement of the oil and oil filter are critical to the correct operation of the lubrication system.

Filtered oil circulates through the engine block and cylinder head.

Oil Passages

Oil passages allow engine oil to circulate to critical engine components. The passages are small and can easily be

plugged or restricted by contaminants in the oil.

Oil Cooler

Oil picks up heat from the engine components and carries the heat into the oil pan or oil cooler. Oil can be cooled

in one of two ways. The first way oil can be cooled is by transmitting heat from the oil pan to the outside air. The

second way oil can be cooled is by circulating the oil through an oil cooler. An oil cooler allows heat to transfer

from the oil to the outside air, much like a small radiator.

Lubricating the Cylinder Walls

Oil is either sprayed from a hole in the connecting rod to the cylinder wall below the piston, or slung onto the

cylinder from controlled leakage from the connecting rod and main bearings. The oil on the cylinder wall seals

the piston rings to the cylinder wall. Without oil to create the seal, combustion gases easily slip past the piston

rings, drastically reducing the efficiency of the engine.


33/94


34/94

NOTESNOTES




35/94



REVIEW QUESTIONS

1-1. List the four strokes in a four-stroke engine:

1. ___________________________________________________________________________________

2. ___________________________________________________________________________________

3. ___________________________________________________________________________________

4. ___________________________________________________________________________________

1-2. Why is the air/fuel mixture compressed before ignition?

______________________________________________________________________________________

______________________________________________________________________________________

1-3. When is the maximum amount of vacuum created?

A. When the throttle plates are closed.

B. When the throttle plates are open.

C. WOT.

D. Vacuum is constant in an internal combustion engine.

1-4. In an electronic fuel injection system, where is fuel delivered?

______________________________________________________________________________________

______________________________________________________________________________________

1-5. What component creates the magnetic field that induces a voltage to fire the spark plug?

______________________________________________________________________________________

______________________________________________________________________________________

1-6. Which harmful tailpipe emission does the EGR system help to reduce?

______________________________________________________________________________________

______________________________________________________________________________________

1-7. What are the three primary functions of the cooling system?

1. ___________________________________________________________________________________

2. ___________________________________________________________________________________

3. ___________________________________________________________________________________

1-8. Incorrect metering of the PCV system can cause:

A. corrosion of internal engine components.

B. blow-by gases to build pressure in the crankcase.

C. excessive parasitic drag.

D. Both A and B.


36/94

NOTESNOTES




37/94

LESSON 2: OIL AND LUBRICANTS


OBJECTIVES

l Identify the primary purposes of engine oils.

l Identify the properties of oil.

l Identify the characteristics of acceptable and

unacceptable oils.

l Identify engine damage related to engine oil.

CONTENTS

l Primary Purpose of Engine Oil

l Oil Properties

l Rating Oils

l Additives

l Engine Damage

l Review Questions


38/94



PRIMARY PURPOSES OF ENGINE OIL

The primary purposes of the automotive lubricating system are:

l Reducing frictional resistance

l Preventing wear

l

Cooling

l Cleaning

l Preventing corrosion

l Sealing

1. Reducing Frictional Resistance

When two solid surfaces are lubricated with oil, the oil divides itself into three layers. Each outside layer adheres

to the solid surfaces. Oil molecules in the center layer slide against each other. The center layer of oil molecules

act like little bearings between the metal surfaces. The friction of the oil molecules sliding against each other is

much less than the amount of friction between two non-lubricated surfaces.

Item Description

1 Outside Oil Layers

2 Center Oil Layer

FS001-B

1

2


39/94



2. Preventing Wear

Oil is pumped through the engine by the oil pump.

The crankshaft rides on a layer of oil. Oil is pumped

into the main bearings at the top where the pressure is

low and is distributed around the bearing by the

rotation of the crankshaft. During the power stroke an

extremely large amount of downward force (A) is

exerted on the connecting rod (B) and crankshaft (C).

This forces the crankshaft down into the bearings.

Because of the extreme pressure, a film of oil on the

bearings is critical to prevent the crankshaft from

coming into contact with the bearings and causing

damage.

Engine wear occurs when metal components are

allowed to contact each other. Oil prevents the engine

components from coming into contact with each

other. When an engine hasnt run for a period of time,

the oil drains back into the oil pan. On start-up there

is a short time lag between when the engine starts and

when all of the engine surfaces are completely

lubricated. The correct viscosity of oil minimizes the

amount of time between start-up and when all

surfaces are completely lubricated.

Oil with the recommended viscosity is thin enough to

quickly flow into all of the areas that require

lubrication on start up, but still thick enough to stay

on the components and provide adequate lubrication

at operating temperature.

RFS022-A

B

C

A


40/94



3. Cooling

Item Description

1 Oil Circulation Path

2 Surrounding Air

The combustion process and the friction between engine components generate heat in an engine. Engine oil plays

a large part in removing heat from the engine. Bearings and moving parts are covered in the oil circulating

through the engine. As the engine oil circulates, heat transfers from the engine components to the oil. Heat

transfers from the oil pan and then to the surrounding air. Some vehicles have oil coolers to increase the transfer

of heat from the oil.

FS003-C

1

2


41/94



4. Cleaning

Item Description

1 Connecting Rod

2 Oil Pan and Oil

3 Leak Area

Contaminants enter the oil from blow-by and condensation. Engine oil suspends the contaminants so they can be

removed from the engine at the next oil change. If allowed to settle, the contaminants would build up in the

engine and restrict or completely block vital oil passages.

To prevent contamination from damaging engine components, the contaminants are from the oil by the oil filter.

If the oil filter is not changed at the recommended intervals, the oil filter may become restricted or completely

blocked. The oil filter has a bypass that allows oil to circulate past the oil filter when the filter is completely

blocked, but the oil is now unfiltered. Unfiltered oil allows the contaminants into the oil passages whererestrictions may occur.

FS004-B

1

2

3


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6. Sealing

Item Description

1 Combustion Chamber

2 Piston Ring

3 Oil

Oil is either sprayed onto the cylinder wall from a small hole in the connecting rod, or slung onto the cylinder

wall by the crankshaft. Engine oil seals the rings to the cylinder walls. Without oil, the engine would have

excessive blow-by and a resulting loss of power.

FS005-C

23

2122

23


44/94



OIL PROPERTIES

Viscosity

Viscosity, or resistance to flow, indicates how well a fluid flows at a given temperature. The viscosity of an oil

(or of any fluid) changes as temperatures change.

Higher temperatures cause the viscosity to decrease, resulting in a thinner oil. Lower temperatures cause the

viscosity to increase, resulting in a thicker oil.

Using a lubricant with too high a viscosity rating causes excessive drag during start-up. The increased time

between when the engine starts and when all surfaces are properly lubricated causes excessive wear.

The weights given on oils are arbitrary numbers assigned by the Society of Automotive Engineers (SAE). These

numbers correspond to real viscosity as measured by several accepted techniques. These measurements are taken

at specific temperatures. The W means the oil meets specifications for viscosity at -18C (0F) and is suitable

for winter use. Using a 40-weight oil when the specifications call for a 30-weight oil is an example of using an oil

with too high a viscosity.

Using a lubricant with too low a viscosity rating causes inadequate lubrication at high temperature. The oil barrier

between the metal surfaces thins to the point of contact, causing excessive wear. Using a 10-weight oil when the

specifications call for a 30-weight oil is an example of using an oil with too low a viscosity.

FS007-A

10-WEIGHT 10-WEIGHT


45/94



Multi-Weight Oil

Oil molecules are different sizes. 5-weight molecules are smaller than 40-weight molecules. Single-weight oil

molecules are all the same size. For example, a 5-weight oil has all 5-weight oil molecules and a 40-weight oil

has all 40-weight molecules.

When the oil is cool, the metal surfaces (A) ride on layers of oil molecules (B). As the temperature increases, the

base oil molecules become more active. The more active oil molecules spread apart, causing the oil to have fewer

molecules in a given area (C). In other words, the oil thins.

The pressure on the metal surfaces remains constant, but when the molecules spread apart the solid surfaces push

them back together, taking up the free space (D). The oil molecules still act as bearings and the metal surfaces are

not in contact with each other, but the layer of oil is thinner.

FS008-A

C

D

BA


46/94



To solve the problem of oil thinning at higher temperatures, a polymer is added to the oil. When the oil is cold,

the polymer is tightly coiled (A). As the temperature increases the polymer uncoils making the polymer wider

(B). The larger diameter of the polymer takes up the room created by the more active oil molecules, forcing the

oil molecules back together. The benefit of adding the polymer is to have an oil that acts like a 5-weight oil atstart-up and like a 30-weight oil at operating temperature.

FS009-C

A

B


47/94



RATING OILS

The American Petroleum Institute (API) rates engine oil. Certification standards are set by US and Japanese auto

manufactures. Oils are tested in various ways to meet the API current required ratings.

Tests evaluate the oils ability to function:

l When the engine is run for short trips and the engine does not fully reach operating temperature.

l When the engine is hot, as with a summertime high load condition.

l During stop-and-go driving.

Engine oil is tested for its effect on fuel economy and its resistance to breaking down over a period of time. If the

engine oil bottle has the starburst API rating on it, the oil meets the current approved standards. Engine oils that

do not meet the current standards mandated by the API are not permitted to carry the API starburst marking. Ford

vehicles use only API approved oil.

Flexible Fuel Vehicles (FFV) require special oil. The oil is marked with the label FFV.


48/94



ADDITIVES

Today, a fully formulated motor oil is made up of 80

percent crude, and as much as 20 percent additives.

Engine oil additives are carefully blended to get the

best balance of properties. Sometimes, certain

additives compete with each other. Friction modifiers

act on the surface of the metal, while anti-wear

additives counteract to a small extent. The oil

manufacturer carefully selects the correct proportions

of each additive to develop the best final product.

Do not add aftermarket oil additives to engine oil.

Aftermarket companies sell additional additives to

add to engine oil. Changing the proportions of the

additives in oil can make the oil less effective, and

upset the delicate balance of the oil blend. Comparethis to making a cake. If the carefully blended recipe

calls for two eggs, will adding seven eggs make a

better cake? Obviously not. In the best case, it would

make no difference, and in the worst case it would

ruin the cake.FS012-A


49/94



Anti-Wear/Extreme Pressure

Anti-Wear/Extreme Pressure additives bond with the metal surfaces to prevent wear under normal operating

conditions. When the engine oil is under extreme pressure, the oil can be pushed out from in between the metal

surfaces it is designed to protect. When this happens, the surfaces can come into contact with each other. Anti-

wear additives react with metal surfaces to form a slippery film, preventing them from coming into contact under

extreme pressure.

Detergents/Dispersants

Detergents are added to engine oil to keep the by-products of combustion (carbon and varnish) from building up

on the engine surfaces. To a small extent, the detergents can clean existing oil deposits, but the main purpose is to

trap contaminants into the oil. Contaminants remain suspended in the oil, so they will be removed from the

engine at the next oil change.

Dispersants work closely with detergents. Dispersants break the contaminants into very fine particles, preventing

them from attaching to each other. The particles are fine enough to easily pass through the oil filter and between

the metal surfaces that are lubricated. Without dispersants, the contaminants form into structures and build up to

restrict or completely block oil passages and the oil filter.

Corrosion Inhibitors

After the engine is shut off, condensation begins to form. This water combines with blow-by to form extremely

corrosive contaminants. Corrosion inhibitors react with metal surfaces to prevent rust. A continuous film covers

the metal surfaces to prevent water from contacting the metal.

Viscosity Index (VI) Improvers

VI improvement additives (friction modifiers) are synthetic oil thickeners that improve the viscosity through the

entire useful range of an oil. To reduce the tendency of the oil to change viscosity as temperatures change, highmolecular weight polymers called VI improvers are added.


50/94



Foam Inhibitors

Foam causes cavitation, overheating due to the reduction in the oils ability to remove heat, and reduced oil pump

efficiency. Foam inhibitors cause air bubbles in the oil to join together and rise to the surface. On the surface of

the oil the bubbles break, removing the air from the oil.

Pour Point Depressants

The lowest temperature at which oil flows is called the pour point. The pour point of engine oil is directly related

to the amount of wax the oil contains. As oil cools, wax structures prevent the oil from flowing. Pour point

depressants bond with individual wax crystals to prevent structures from forming.

Oxidation Inhibitors

At high temperatures, oxidation causes the oil to become thicker and darker, resulting in sludge. Oxidation

inhibitors give the oil a longer life by retarding the reaction of the oil and oxygen.

ENGINE DAMAGE

Without sending engine oil out to a laboratory to be tested, there is no good way to identify that oil is functioning

properly. Because of the residual oil left in an engine when the oil is drained, new oil tends to turn dark very

quickly.

Fuel smell in the oil and inappropriate oil level are two concerns that can indicate an engine concern. As a rule, if

the quality of oil is in question the oil and filter should be replaced.

Oil can be sent out to a testing facility for diagnosis, but this is an uncommon practice. If oil is to be sent out,

include an unused sample of the appropriate oil for comparison.


51/94



Low Oil Level

The first thing to notice when checking the engine oil is the oil level.

A low oil level may indicate an engine that is burning or leaking oil. Too much oil causes the oil to foam,

reducing the efficiency of the oil pump and causing cavitation.

Varnish

FS013-A

MIN MAX

Varnish (A) on the dipstick may indicate that the engine oil has not been changed at regular intervals.

FS014-A

MIN MAX

A


52/94



Coolant in the Oil

Oil that has a milky color is an indication of coolant in the oil. Coolant in the oil can be caused by a blown head

gasket, cracks between the oil and coolant passages, or a water pump shaft that has damaged the timing cover.

Coolant in the oil removes the lubricating qualities of the oil.

FS015-A

MIN MAX

Contaminated Oil

Excessive particulate contamination in the oil can

cause internal engine damage. The particles can

scratch or become embedded in the bearings.

Excessive contamination can be caused by:

l failure to perform standard maintenance.

l excessive blow-by.

l a failed, incorrectly installed or missing air filter.

l restricted or improper oil filter.

l restricted PCV system.

FS037-B


53/94


54/94

NOTESNOTES




55/94

LESSON 3: FUELS


OBJECTIVES

l Identify engine driveability concerns related to

fuel.

l Identify the characteristics of acceptable and

unacceptable fuels.

l Identify the purpose of fuel additives.

l Identify the properties of the different fuels.

l Identify the different types of fuels used in Ford

and Lincoln/Mercury vehicles.

CONTENTS

l Types of Fuel

l Gasoline Additives

l Additives That Do Not Improve Performance

l Alternative Fuels

l Review Questions


56/94

LESSON 3: FUELS


TYPES OF FUELS

Types of fuels covered in this class include gasoline

and alternative fuels including Liquid Propane Gas

(LPG), Compressed Natural Gas (CNG), and

Methanol/Ethanol. Diesel and electric power are

covered in other classes.

Gasoline

Gasoline is the fuel designed for spark-ignition

internal combustion engines. Derived from

petroleum, gasoline consists of over 200 different

hydrocarbons.

Modern distillation processes create hydrocarbons

with the desirable volatility and characteristics

necessary for good engine performance. Additives

(added during the manufacturing process) enhance the

performance of the gasoline.

Alternative Fuels

Alternative fuels like CNG and LPG burn cleaner

with fewer hydrocarbon emissions. Although Ford

Motor Company does develop electric vehicles, only

spark ignition vehicles are covered in this course.

FS016-A

GA

SOLINE


57/94

LESSON 3: FUELS


Volatility

FS017-A

GASOL

INE

Volatility is gasolines ability to evaporate. In the intake manifold, high volatility allows air and fuel to properly

pre-mix before combustion. In the gas tank, low volatility prevents the fuel from evaporating and causing high

emissions.

Gasoline manufacturers balance the need for proper atomization with the reduction of hydrocarbon emissions.

The result is a carefully blended fuel that is adjusted seasonally and geographically to account for weather

extremes. Use of the wrong blend results in driveability concerns.

Like engine oils, there are plenty of aftermarket products that claim to make gasoline more effective in one way

or another. All necessary gasoline additives are added during the manufacturing process; no additional

aftermarket additives are needed.


58/94

LESSON 3: FUELS


GASOLINE ADDITIVES

FS018-A

Octane/Antiknock Compounds

Antiknock compounds increase the antiknock quality of gasoline. Gasoline containing tetraethyl lead was first

marketed in 1923. The average concentration of lead in gasoline gradually was increased until it reached amaximum of about 2.5 grams per gallon (g/gal.) in the late 1960s.

New refining processes producing higher octane gasoline components, steady growth in the population of

vehicles requiring unleaded gasoline, and EPA regulations requiring the reduction of the lead content of gasoline

began in 1979. In 1996, the EPA completely banned the addition of lead additives to gasoline.

After lead was banned from gasoline, manufacturers developed higher octane gasoline to prevent engine knock.

Spark knock is the sound made when the air/fuel mixture is ignited in one part of the combustion chamber and the

spark plug ignites the remaining mixture in a different part of the combustion chamber. The collision between the

two flame fronts results in a knocking sound. Combustion chamber pressures rise significantly when the flame

fronts collide, causing engine damage.

Octane controls the flash point, or the temperature required for ignition of the fuel. With the correct octane, the

flash point of the fuel is high enough to prevent the hot carbon deposits from igniting a second flame front. The

result is correct combustion in the cylinder.

Without sufficient octane to prevent knock, the Electronic Engine Controls (EEC) retard the timing causing a loss

of power. Using fuel with the correct octane after a sub-standard fuel has been used may appear to increase

power. This, however, does not make the statement higher octane increases engine power correct. Using the

correct octane fuel allows the EEC to set the timing for more efficient engine operation. Once the octane is

sufficient to prevent knock, additional octane does not increase power or fuel economy.


59/94

LESSON 3: FUELS


Oxidation Inhibitors

Oxidation inhibitors (also called antioxidants) prevent gasoline components from reacting with oxygen in the air

to form peroxides or gums. Peroxides can degrade antiknock quality and attack plastic fuel system parts. Soluble

gum results in engine deposits, and insoluble gums plug fuel filters.

Metal Deactivators

Active metals, like copper and zinc, effectively catalyze the oxidation of gasoline. For this reason, active metals

like copper and zinc are not used in most gasoline distribution and vehicle fuel systems. When they are present,

metal deactivators inhibit their catalytic activity.

Demulsifiers

Demulsifiers improve the water separating characteristics of gasoline.

Deposit Control Additives

Deposit control additives reduce the build-up of deposits on the throttle body, intake manifold, fuel injectors,

intake ports and valves. Early deposit control additives controlled deposits on intake valves, but caused depositsin the combustion chambers. Since then, deposit control additives have been improved to prevent intake deposits

without adding combustion chamber deposits.

Anti-Icing Additives

Anti-icing additives prevent ice formation in the fuel system. The need for this additive is disappearing as

vehicles with fuel injection systems replace vehicles with carburetors.

ADDITIVES THAT DO NOT IMPROVE PERFORMANCE

The following additives have no effect on engine performance, but instead are used for identification andhandling reasons.

Dyes

Dyes are oil-soluble solids and liquids used to visually distinguish batches, grades, or applications of gasoline

products. For example: Gasoline for general aviation, manufactured to more exacting requirements, is dyed blue

to distinguish it from motor gasoline for safety reasons.

Corrosion Inhibitors

Tanks and pipelines of the gasoline distribution and marketing system are constructed primarily of uncoated steel.

Corrosion inhibitors prevent free water in the gasoline from rusting or corroding these facilities. Corrosion

inhibitors are less important once the gasoline is in the vehicle. The metal parts in the fuel systems of todays

vehicles are made of corrosion-resistant alloys coated with corrosion-resistant coatings.

Drag Reducers

As energy costs have increased, pipelines have sought more efficient ways to ship products. Drag reducers lower

pumping costs by reducing friction between the flowing gasoline and the walls of the pipe.


60/94

LESSON 3: FUELS


Engine Concerns Related to Gasoline

Contaminated fuel causes sluggish operation, misfire,

hard/no-start, and other driveability concerns. Water

in the fuel causes rust to form in steel lines, misfire or

hesitation at low speeds, and hard/no-start conditions.

To identify fuel concerns due to contaminated fuel,remove the fuel line from the tank side of the fuel

filter. (Removing the line from the tank side of the

fuel filter prevents the fuel filter from removing

contamination.) Pump some of the questionable fuel

into an approved clear glass container and hold the

container up to the light. Inspect the fuel for

contaminants that may be in the fuel. Dirt, rust and

other particulate contamination may be floating in the

fuel or may settle to the bottom of the container.

Allow the fuel to settle. Water in the fuel settles to the

bottom of the container.

NOTE: If contamination in the fuel tank is identified,

flush the fuel tank.

Item Description

1 Fuel

2 Water

3 Contaminants

FS021-B

3

1

2


61/94

LESSON 3: FUELS


Contaminants in the fuel cause restrictions in the fuel system components.

Restrictions may occur in the fuel injectors, fuel filter, fuel pump pick-up, or fuel lines.

NOTE: Simply changing a restricted fuel component (such as a filter or injector) may only cure the symptom. If

the root cause of contaminated fuel is not identified, the new filter quickly becomes restricted, and the condition

will reoccur.

FS022-A


62/94

LESSON 3: FUELS


Fuel Storage

FS020-A

The volatility requirements for gasoline are different in the summer than they are in the winter. If a summer blend

is used in the winter, or a winter blend used in the summer, driveability concerns may occur. To prevent the use

of the wrong blend, gasoline should be used as quickly as possible.

If gasoline absolutely needs to be stored, store gasoline in an approved, tightly closed, full or almost full

container. Add fuel stabilizer and store the container in a cool dry place. Appropriately stored fuel stays good for

at least a year.


63/94

LESSON 3: FUELS


ALTERNATIVE FUELS

Methanol/Ethanol

Methanol and ethanol are two forms of alcohol fuel. Both are made from non-petroleum products.

Methanol is made from coal, and ethanol is made from farm products such as corn, potatoes, or sugar cane. Both

alcohols have a higher octane than gasoline. Some areas require ethanol/methanol to be added to gasoline because

they reduce carbon monoxide by as much as 39%.

Compressed Natural Gas (CNG)

FS042-A

The main part of natural gas is methane. CNG is stored in the fuel tank at pressures between 20,684 kPa

(3,000 psi) and 24,821 kPa (3,600 psi). The CNG enters into the combustion as a gas, at approximately 100 psi.

Natural gas is a mixture of hydrocarbons (mainly methane [CH4]) and is produced either from gas wells or

in conjunction with crude oil production. For more information on CNG, consult the STARS guide for the

CNG class.


64/94

LESSON 3: FUELS


Liquid Propane Gas (LPG)

Propane gas is a by-product of the petroleum refining process. In its natural state, propane is a gas. Under mild

pressures (137 kPa [200 psi] or less), propane turns to a liquid.

Liquid propane is stored in the fuel tank. As the fuel crosses through a pressure regulator, the liquid propane

changes to a gas.

Propane burns cleaner than gasoline, but contains less energy per unit than gasoline.

LPG vehicles have less carbon build-up than gasoline engines. LPG vehicles emit about 20% fewer oxides of

nitrogen (NOx), and about 60% fewer carbon monoxides.


65/94

LESSON 3: FUELS


REVIEW QUESTIONS

3.1. Volatility is:

A. diesels measure of ignition.

B. gasolines ability to evaporate.

C. resistance to pre-ignition.

D. methanes mixture of hydrocarbons.

3.2 If a vehicle comes in for a new fuel filter shortly after replacing one, the root cause may be:

A. water in the fuel.

B. high octane.

C. contaminated fuel.

D. low octane.

3.3 Using fuel with a winter blend in the summer may result in:

A. driveability concerns.

B. increased horsepower.

C. contaminated fuel.D. oxidation.


66/94

NOTESNOTES

LESSON 3: FUELS



67/94

LESSON 4: COOLANT


OBJECTIVES

l Identify characteristics of unacceptable coolant.

l Describe engine concerns related to coolant.

CONTENTS

l Purpose of Coolant

l Types of Coolant

l Review Questions


68/94

LESSON 4: COOLANT


PURPOSE OF COOLANT

Automotive engines generate a great deal of heat.

The exhaust valve can reach temperatures of 648.8C

(1,200F). This heat must be removed from the

engine.

The cooling system is designed to keep enginetemperatures low enough to prevent overheating, yet

still high enough to help control emissions and heat

the passenger compartment in colder weather. FS027-A


69/94

LESSON 4: COOLANT


TYPES OF COOLANT

Ethylene Glycol Coolant

Ford Motor Company does not recommend or endorse the use of engine coolants made with propylene glycol in

Ford vehicles. Available information indicates that current propylene glycol-based engine coolants on the market

provide less heat transfer, and some may not provide enough corrosion protection to meet Ford specifications.

Furthermore, the claims of toxicological and environmental advantages of propylene glycol may be misleading.

Ethylene glycol coolants raise the boiling point and lower the freezing point of the water they are mixed with.

Ethylene glycol raises the boiling point of water (pure water has a boiling point of 100C [212F] and a

50/50 mixture has a boiling point of 108C [227F] at sea level) and lowers the freezing point of water

(pure water has a freezing point of 0C [32F] and a 50/50 mixture has a freezing point of -36C [-34F]

at sea level).

In Oregon, coolant is required by law to have a bittering agent, to protect children and animals from drinkingcoolant. Ethylene glycol coolants are poisonous and must be handled appropriately to prevent them from being

taken internally.

A pressure cap attached to the radiator pressurizes and seals the cooling system. The cooling systems increased

pressure raises the coolants boiling point to add a comfortable margin between the engine operating temperature

and the boiling point of the coolant.

Ethylene glycol coolants lubricate and prevent corrosion at all temperatures.

FS045-A

32F 212F

0C 100C

-34F 227F

-36.6C 108.3C


70/94

LESSON 4: COOLANT


Organic Acid Technology Coolant

Organic Acid Technology (OAT) coolant is designed

to be an extended life coolant, which will reduce

cooling system maintenance.

OAT coolant is orange in color to distinguish it from

green coolant and has special additives to lubricateand protect the cooling system from corrosion. OAT

coolant is only used in limited applications and is not

compatible with green coolant.

FS026-A

50%/50%

-34 -227

FS027-A

Coolant and Water Mixture

Ethylene glycol and OAT coolants are mixed with

50% water.

NOTE: To ensure correct mixing of the coolant and

water solution, pre-mix in a container and then add

the mixture to the cooling system.

Extreme climates (below -36C [-34F]), may require

a concentration slightly above 50%, but never more

than 60% coolant.

In most cases, tap water is fine for use in the cooling

system, but hard water should be avoided. Hard water

can leave deposits in the cooling system, reducing the

ability of the cooling system to transfer heat.


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LESSON 4: COOLANT


Coolant Additives

Anti-Corrosion

Anti-corrosion additives protect the cooling system.

Cooling system corrosion causes the internal parts of

the engine to scale or pit, dramatically reducing the

cooling systems ability to cool the engine.

Organic acids are slowly formed when oxygen

dissolved in the coolant, in combination with a hot

metal surface which may act as a catalyst, oxidizes

ethylene glycol to glycolic acid. Minor amounts of

formic and acetic acids can also be formed. When

these acids exceed normal levels the anti-corrosion

additives can no longer protect the cooling system.

Anti-Foaming

When coolant foams, cavitation occurs in the cooling

system. Cavitation causes the internal surfaces of the

cooling system to become pitted and damaged.

Foaming also inhibits the ability of the pump to move

coolant through the cooling system.

Lubricants

Lubricants keep the water pump lubricated.

FS036-A


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LESSON 4: COOLANT


Coolant Inspection

Visual inspection of engine coolant is very helpful in engine diagnosis. Inspect coolant color in both the radiator

coolant recovery reservoir and the radiator.

Dark brown coolant is an indication of the use of an unauthorized stop leak. If an unauthorized stop leak has been

used, flush the cooling system. The leak must be identified and repaired and the cooling system filled with the

correct mixture of water and Premium Engine Coolant (E2FZ-19549-AA).

E6AZ-19558-A Radiator Stop Leak is an approved, permanent way to repair small cooling system leaks.

Light brown or reddish coolant, or particles in the coolant indicates rust in the cooling system. If rust or corrosion

is found in the coolant, the cooling system needs to be flushed and filled with the correct mixture of water and

Premium Engine Coolant (E2FZ-19549-AA).

An iridescent sheen on top of the coolant indicates a trace of oil is entering the cooling system. This is an

indication of a small concern that is going to get worse.

Engine oil leaking past a gasket (intake manifold, or head gasket) into the cooling system causes the coolant to

have a milky brown color. Transmission fluid leaking into the cooling system from the transmission cooler causesthe coolant to have a milky reddish color. A water pump that has damaged the timing chain cover or a crack in

the engine block between the lubrication and cooling systems allows oil into the cooling system.

When oil is found in the cooling system, coolant is also found in the oil. To determine where the oil is coming

from, inspect the engine oil and transmission oil for coolant.

Color is not the only indicator of the quality of the engine coolant. For example, coolant that has overheated, or

has not been changed at the required intervals, may look fine but can cause rust and scaling in the cooling system.

Remember, coolant loses its anti-corrosion properties over time. Therefore, following recommended cooling

system maintenance intervals is critical.

Flushing/Backflushing

Flushing/backflushing helps remove contaminated coolant, rust and scale from the cooling system. The cooling

system Flush-All, flush kit hardware package and drain kit are used to flush the cooling system. Follow the

service manual procedures for flushing/backflushing the cooling system.

Residual water remaining in the cooling system after flushing/backflushing may dilute the strength of the coolant

mixture. Test the coolant strength after running the engine long enough to circulate the coolant, and adjust the

mixture as necessary.


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LESSON 4: COOLANT

Engine Repair Fund

Documents

Engine Repair Fundamentals - Self Study