Clutches

Auto 3/4Mr. Saunders

GO

12/2001 VHS AUTO 3

Who needs a clutch?

12/2001 VHS AUTO 4

Not me!

12/2001 VHS AUTO 5

Big Daddy Don Garlits

12/2001 VHS AUTO 6

Clutches

Lets read together starting on page #

Black bookChapter 44

12/2001 VHS AUTO 7

Clutches 44-1 Purpose

of the Clutch Someone read

please

12/2001 VHS AUTO 8

Purpose of the Clutch Allows engine to be disengaged

from transmission for shifting gears and coming to a stop

Allows smooth engagement of engine to transmission

NOT !NOT !NOT !

12/2001 VHS AUTO 10

Clutches 44-2 Location of the Clutch

Someone read pleaseRear wheel drive

Front engineRear engineMid engine

Front wheel drive

12/2001 VHS AUTO 11

Clutches 44-3 Construction of the

Clutch Read along with me

12/2001 VHS AUTO 12

Clutches 44-3

Construction of the Clutch

Coil spring pressure plate (cover and pressure plate)

READ ON

12/2001 VHS AUTO 13

Clutches 44-3

Construction of the Clutch

Splines to input shaftOf transmission

Clutch Disk orFriction Disk

READ ON

12/2001 VHS AUTO 14

Pilot Bushing or bearing

READ ON

12/2001 VHS AUTO 15

Clutches 44-3

Construction of the Clutch

Flywheel boltsto crankshaft

Pressure plate & coverbolt to flywheel

If there is a chance you will be reusingpressure plate, make alignment marksto flywheel to maintain proper balanceBEFORE removal

When unbolting pressure plate from theflywheel, remove bolts evenly as not tobend the cover. REMEMBER, this is under high spring pressure.

12/2001 VHS AUTO 16

Flywheels Add weight to crank for non-power strokes Has ring-gear for cranking engine (usually

replaceable)

12/2001 VHS AUTO 17

Flywheels

Hot spots

12/2001 VHS AUTO 18

Flex plates Ring gear for automatic transmissions Light weight, bolts crank to torque

converterSometimes too

light weight

12/2001 VHS AUTO 19

Clutches 44-4 Operation of

the ClutchSomeone read please

12/2001 VHS AUTO 20

Clutches

Bolted to Crank

(friction disk) splined to transmissionInput shaft

(throw-out bearingT/O bearing) allowsto push on rotatingclutch fingers

Bolted to flywheel - Applies the spring force to clamp thefriction disk to the flywheel

(clutch fork) pushesT/O bearing to releaserotating clutch

Pilot bushing or bearing in centerof flywheel or crankshaft, supportsthe end of input shaft

12/2001 VHS AUTO 21

Pressure Plate

PivotsT/O bearing

Moves pressurePlate right

Releases friction diskfrom flywheel

12/2001 VHS AUTO 22

Clutch terms Clutch disengaged

Clutch pedal is in or down Clutch engaged

Clutch pedal is out or upWhat would it mean if someone said the clutch pedalIs engaged?Make sure you know if you are talking about the clutch or the clutch pedal !!!

12/2001 VHS AUTO 23

Throw out Bearing (release bearing) Slides on transmission input shaft

bearing retainer

READ ON

12/2001 VHS AUTO 24

Clutches

READ ON

12/2001 VHS AUTO 25

Throw out bearings Most need clearance between fingers of

pressure plate so it isn’t spinning all the time (free play)

Riding the clutch (foot resting on pedal) Pushes T/O bearing into pressure plate fingers Causes it spin constantly

Wearing it out too soon Releases some of clutch spring pressure

Causing clutch to slip

12/2001 VHS AUTO 26

Slipping clutch ?

12/2001 VHS AUTO 27

Free play Clearance between T/O bearing and

clutch fingers Measured at clutch pedal

Usually 1 ½ inches of free movement Goes away as clutch disk wears

thinner Some manufactures use T/O bearings

that always ride on the clutch fingers Usually self adjusting READ ON

12/2001 VHS AUTO 28

www.howstuffworks.com web site

In the search, type in “Clutch”

12/2001 VHS AUTO 29

44-5 Clutch Linkage Someone read please

12/2001 VHS AUTO 30

44-5 Clutch Linkage Can be very

complicated Have the right amount

of movement and direction without too much pedal pressure

Wear Motor mounts Spring to pull T/O

bearing away Has to be lubricated

12/2001 VHS AUTO 31

Over-center spring Helps pull up on

clutch pedal

Helps pull down on clutch pedal

12/2001 VHS AUTO 32

Clutch fork

T/O bearinghooks here

Fulcrum point

What wouldcause this?

12/2001 VHS AUTO 33

Skip to 44-10 Hydraulic clutch

Some one read please

12/2001 VHS AUTO 34

Hydraulic clutch Uses master cylinder and slave

cylinder Uses brake fluid Must be bleed

12/2001 VHS AUTO 35

Hydraulic clutch No complicated

linkage Can easily

control mechanical advantage with piston sizes

Self lubricating No motor mount

problemsService just like you would hydraulicbrakes

12/2001 VHS AUTO 36

Slave cylinder

Some are adjustablefor free-play and

some not

12/2001 VHS AUTO 37

Ford’s slave cylinders Some are part of T/O

bearing Can’t change without pulling

tranny (inside bellhousing)

Can be a royal pain to bleed

12/2001 VHS AUTO 38

Cable clutch No complicated

linkage Flexibility No motor mount

problems

12/2001 VHS AUTO 39

Linkage/Cable/Hydraulic controls

12/2001 VHS AUTO 40

Back to 44-6 Friction disks Someone read please

12/2001 VHS AUTO 41

Friction disks

Often made of asbestos

Must be put in only one way Usually

marked Clutch won’t

release if wrong

12/2001 VHS AUTO 42

Friction disks

Cushion springs Waved metal between clutch half's Dampen clutch engagement

12/2001 VHS AUTO 43

Friction disks Torsional springs

Can be spring or rubber Dampen power impulses from

crankshaft

12/2001 VHS AUTO 44

Torsional SpringsHas pins to limit amount of twist.

Springs try to keep it centered between pins.

Springs sometimes get weak and start rattling or fall out

12/2001 VHS AUTO 45

Clutch disksFriction material isn’t very thick.Minimum thickness around .012”

12/2001 VHS AUTO 46

Clutch disksWell, uhh…..

Dad, I only got on it a little bit

Does side stepping

the clutch at

6000 RPM

count?

12/2001 VHS AUTO 47

44-7 Types of Clutches Someone read please

12/2001 VHS AUTO 48

Types of Clutches (pressure plates)

Coil spring 9 spring 12 spring

3 fingers for T/O bearing to push on

12/2001 VHS AUTO 49

44-8 Diaphragm-Spring Clutches Someone read please

12/2001 VHS AUTO 50

Diaphragm-Spring Clutches

12/2001 VHS AUTO 51

44-9 Centrifugal Clutch Someone read please

12/2001 VHS AUTO 52

Centrifugal Clutch The faster the RPM, the harder the

clutch disk is squeezed

12/2001 VHS AUTO 53

Centrifugal Clutch

T/O bearing

Pressure plate

12/2001 VHS AUTO 54

Centrifugal Clutch

12/2001 VHS AUTO 55

44-11 Clutch safety switch Someone read please

12/2001 VHS AUTO 56

Clutch Safety Switch Prevents from cranking with clutch

engaged Some standard transmissions

won’t let you take the key out and lock the steering column with out the transmission in reverse Prevents steering lock while moving

forward

12/2001 VHS AUTO 57

Think Do you know the names of the clutch parts and what they do?

How would motor mounts affect the clutch?

What pulls the clutch linkage back? What would happen if free-play is

incorrect? How would crankshaft end-play

affect the clutch? What if the pilot bushing was worn,

or seized up? What happens to free-play with

disk wear?

12/2001 VHS AUTO 58

CDX Review Disk 15 Clutches

Clutch Components Principals of a clutch Single plate clutches Multi-plate clutches Operating mechanisms

12/2001 VHS AUTO 59

CDX Review

12/2001 VHS AUTO 60

Look at the chart on page 462 and 463 Clutch trouble diagnosis chart

12/2001 VHS AUTO 62

Need to Know What would cause and not cause:

Clutch slippage Clutch chatter Hard shifting Clutch noises Clutch pedal pulsations Clutch application problems

12/2001 VHS AUTO 63

Checking Flywheel for Run-out

12/2001 VHS AUTO 64

Checking pressure plate for warpage

12/2001 VHS AUTO 65

Clutch Disk Replacement Very wise to:

Have flywheel surfaced (even with no run-out or hot spots)

Replace pilot bushing or bearing Replace T/O bearing Replace pressure plate (cover, plate

springs)

12/2001 VHS AUTO 66

Clutch Disk Replacement Very wise to inspect & replace as

necessary: Clutch fork & pivot Input shaft bearing retainer on

transmission (where T/O bearing slides) Linkage, cable or hydraulic components Motor mounts Flywheel ring gear

12/2001 VHS AUTO 67

Installing new clutch Drive in pilot bushing or bearing

with bushing driver

12/2001 VHS AUTO 68

Installing new clutch Loctite and torque flywheel to

specifications on a clean crankshaft hub

12/2001 VHS AUTO 69

Installing new clutch You must use clutch alignment tool

(pilot shaft) when bolting up pressure plate Torque and Loctite pressure plate to

specifications Use a crossing pattern to pull

pressure plate down evenly

12/2001 VHS AUTO 70

Universal clutch alignment tool Select end that fits tight in pilot

bushing or bearing

12/2001 VHS AUTO 71

Universal clutch alignment tool

12/2001 VHS AUTO 72

Universal clutch alignment tool

12/2001 VHS AUTO 73

Clutch Alignment tools (pilot shaft)

12/2001 VHS AUTO 74

Alignment studs Cut off bolts

screwed into engine block

Prevents from bending clutch disk when installing transmission

12/2001 VHS AUTO 75

Adjust clutch Shorten or lengthen linkage or

cable to reach proper free-playJam nut

Adjusting nut

12/2001 VHS AUTO 76

We will do standard transmissions after Christmas

12/2001 VHS AUTO 77

Clutch questions?