Chapter 13

Chapter 13 Chapter 13 - Start

Added : 2016-04-25 Views :26K

Download Presentation

Chapter 13




Download Presentation - The PPT/PDF document "Chapter 13" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.



Presentations text content in Chapter 13

Slide1

Chapter 13

Engine Sealing and Reassembly

Slide2

Torque Principles

All metals are elastic

Bolts can stretch and compress

Stretch applies clamping force

Too much stretch destroys the bolt

Bolts torqued to yield never return to normal

Slide3

Slide4

Torque Principles (Cont.)

Most torque values are for dry fasteners

Lubricants increase applied torque

Visually inspect the bolts

Use lubricants or sealers as specified

Tighten in the correct sequence

Ensure proper fastener is used

Slide5

Tightening Sequence Examples

Slide6

Threads must be clean and undamagedUse liquid sealant or engine oil on threadsInstall bolts in their proper holesRun a nut over the bolt’s threads by handClean bolt and cylinder block threads with a thread chaser or tapTighten bolts to the proper torque specification

Bolt Installation Tips

Slide7

Thread Cleaning

Slide8

Thread Repair

Overtorquing or incorrect threading will strip threads

May be repaired using thread insert or Helicoil

Slide9

Torque-To-Yield Bolts

TTY fasteners are designed to stretch when properly tightened

Once at yield point the bolt is permanently stretched

Commonly used as cylinder head bolts

Torqued in steps

Slide10

TTY Bolts (Cont.)

Slide11

Knowledge Check

Why is proper tightening of bolts necessary when installing engine components?

Slide12

Gaskets

Used to provide a positive seal between parts bolted together

Also act as spacers, wear insulators, and vibration dampers

Gaskets are used on stationary parts

Seals are used with moving parts

Slide13

Cut or Soft Gaskets Made of cork, rubber, or paperSilicone Gasket MaterialThree different typesHard Gaskets Made of steel, copper, or a composite of metal and fiberSealantsUsually in liquid form

Gasket Classifications

Slide14

Paper/Fiber Gaskets – low temperature/low pressure Cork Gaskets – not commonly used today

Cut Gaskets

Slide15

Other Gaskets

Molded Rubber Gaskets – retain flexibility and are durable

May have steel insert around bolt holes

Do not use sealants or adhesives

Hard Gaskets – made from steel and other materials

Used as cylinder head and exhaust manifold gaskets

Slide16

Slide17

Replacement Gaskets

Available individually or as sets

A full set contains all gaskets necessary for rebuilding an engine

Some components are assembled using form in place gaskets

Check TSBs for updated gaskets

Slide18

Never reuse old gasketsHandle new gaskets carefullyEnsure clean mating surfaces

General Gasket Installation

Slide19

General Gasket Installation

Use the right gasket in the right positionOnly use sealants when specifiedMake sure all threads are clean and undamaged

Slide20

Head GasketsSeals combustion, coolant, and oilExposed to very low temperatures to combustion temps of 2000 – 4000 °FSeals vacuum and combustion pressures (1000 psi peak pressures)Allows for movement between head and blockMost late model engines use MLS gaskets

Specific Engine Gaskets

Slide21

MLS Gasket

Slide22

Common Head Gasket Failure

Preignition/Detonation

Incorrect timing or mixture, vacuum leak, faulty cooling system

Engine Overheating

Improper Installation

Wrong head or block surface finish, incorrect bolt tightening, stretched bolts, improper sealant use, incorrect gasket

Slide23

Slide24

Specific Engine Gaskets (Cont.)

Manifold Gaskets

Intake, exhaust, or combination

Valve Cover Gaskets

Must seal between different metals or materials

Oil Pan Gaskets

Seal between the block and pan

EGR Valve

Gasket may be used to regulate exhaust flow

Slide25

Adhesives

Used only to hold a gasket in placeDo not assembly until adhesive is dry

Slide26

Aerobic SealantsCure only when exposed to oxygen (air)Are commonly used to form gasketsAnaerobic SealantsCure only in the absence of oxygen (air)Are used for thread sealant

Types of Sealants

Slide27

Types of Sealants (Cont.)

General Purpose Sealants

Available in liquid, brush on, or aerosol types

Ensure sealant is O

2

sensor safe

Never use a hard drying sealant on gaskets

Thread Sealants

Used on bolts passing through a liquid passage

Slide28

Types of Sealants (Cont.)

Silicone Sealants

Formed-in-place gasket

Applied to mating surfaces

Room Temperature Vulcanizing (RTV) most common

Too much RTV can be squeezed out and into oil system

Slide29

Applying RTV

Slide30

Antiseize Compounds

Prevents dissimilar metals from reacting with each other and seizing

Commonly used on aluminum parts

Always follow manufacturer recommendations when using

Slide31

Knowledge Check

Technician A says gaskets are used between moving parts of the engine. Technician B says liquid RTV gasket maker can be used in place of any engine gasket. Who is correct?

Slide32

Engine Gaskets and Seals

Slide33

Used with rotating partsThree basic typesFiber-packingTwo-piece lipOne-piece radial

Oil Seals

Slide34

Oil Seals (Cont.)

Slide35

Two-Piece Lip Seal

Slide36

Engine Reassembly

Clean and lubricate head bolts

Match head gasket to block

Place head on block and alignment dowels

Torque head bolts in sequence

Lube pushrods and rocker arms

Slide37

Timing Belts and Chains

Cam and crank alignment is critical

Follow timing procedures exactly

Ensure the tensioners apply properly

Slide38

Methods of ValveLash Adjustment

Rocker arms with adjustable pivotsAdjustable push rodsRocker arms with adjustable screwsAdjustable cam followersSelective shims

Slide39

Final Assembly Steps

Install various covers, pulleys, and sensors

Ensure coolant drain plugs are installed

Coat sensor O-rings with oil before installing

Install vibration damper onto crankshaft

Make sure manifold mating surfaces are clean and install manifolds

Slide40

Final Assembly Steps (Cont.)

Install the thermostat and housing

Install the flexplate and torque converter or the flywheel and clutch components

Inspect and loosely install motor mounts

Install all other related components as necessary

Slide41

Knowledge Check

What are two methods of adjusting valve lash?

Slide42

Always refer to the manufacturer’s service informationPrime the oil pump prior to starting the engineFollow the manufacturer’s computer relearn procedures if applicable

Engine Installation Tips

Slide43

Starting Procedure

Set ignition timing as closely as possible

Fill fuel tank with several gallons of fresh fuel

Start engine and run at 1500 RPM

Run until engine reaches normal operating temperature then shut off

Recheck all adjustments

Slide44

Break-In Procedure

Test drive at 30 MPH and accelerate to 50 MPH at full throttle

Repeat at least 10 times

Apply loads to engine for short periods

This helps assure the rings seat

Slide45

Relearn Procedures

The computer will need to learn the engine condition and make adjustments

Idle and transmission shift schedules will relearn

Reset any memory functions such as the clock and radio presets

Slide46

Slide47

Slide48

Slide49

Slide50

Slide51

Slide52


About DocSlides
DocSlides allows users to easily upload and share presentations, PDF documents, and images.Share your documents with the world , watch,share and upload any time you want. How can you benefit from using DocSlides? DocSlides consists documents from individuals and organizations on topics ranging from technology and business to travel, health, and education. Find and search for what interests you, and learn from people and more. You can also download DocSlides to read or reference later.
Youtube