1. Clutches

2. Basic purpose Used to disengage engine from input shaft Flywheel
Bolted to crankshaft
Provides surface for clutch disc to work on
Clutch disc
Splined to transmission input shaft
Fits between flywheel and pressure plate

3. Basic purpose Pressure plate Bolted to flywheel
Applies squeezing pressure to disc
Acted on by throw out bearing

4. Flywheel

5. Flywheel Acts as engine balancer Adds inertia to engine rotation
Works with crank balancer to smooth out firing pulses
Some will be balanced to engine
Adds inertia to engine rotation
Works as heat sink for clutch
Ring gear for starter engagement
Some vehicles have dual mass flywheel

6. Flywheel service
Visually inspect for hot spots, grooves, scoring and cracks
Check with dial indicator for runout and crank end play
Most flywheels can (should) be resurfaced
Must remove dowel pins
Inspect ring gear

7. Flywheel service
Flywheel should be marked before removing to maintain balance
On Front wheel drive cars a lot of Flywheels are used for Ignition timing marks. They should be marked before removing. Some will only bolt on one way don’t take the chance MARK IT

8. Clutch disc

9. Clutch disc Friction material disc splined to input shaft
Friction material may contain ASBESTOS
Friction material can be bonded or riveted
Friction is attached to wave springs
Most have torsional dampener springs
Normal wearing component
Normally a worn out disc will cause slipping

10. Clutch disc service Inspect for wear similar to brake pads
Common to have loose or broken springs
Common failure due to oil contamination
Must find cause BEFORE repair
Normally purchased in kit containing pressure plate, disc, throw out bearing

11. Clutch disc service Clutch disc will normally have a flywheel side
Disc must be centered with clutch alignment tool before pressure plate bolted down
Make sure new disc fits on input shaft of the transmission before you install it

12. Pressure plate

13. Pressure plate Provides clamping pressure to disc
Works like spring loaded clamp
Bolted to _________________
Can use Belleville spring acted on by Throw Out bearing
Can use coil springs and levers acted on by Throw Out bearing

14. Pressure plate service
Mark relation to flywheel if reused
Remove bolts slowly in criss-cross pattern
Inspect fingers for parallelism, cracking or uneven wear
Inspect friction surface for hot spots, cracks etc and with straight edge for warpage
Must be torqued to specs and in sequence
Uses hard bolts

15. Release/ throw out bearing

16. Release/ throw out bearing
Acted on by clutch fork - acting on pressure plate
Moves toward flywheel when pedal pushed
Slides on front portion of transmission called bearing retainer
Normally not in contact with pressure plate until pedal pushed

17. Release bearing service
Very common failure - isolated by lightly applying clutch and listening
Inspect for looseness or roughness
Most are sealed but some were lubeable
Clutch fork must be lubed at pivot point and bearing contact points
Bearing retainer and input shaft should be lubed
Clutch fork must be secured at the pivot point

18. Pilot bearing / bushing
Used on some cars
Supports front of transmission input shaft
Can be needle bearing or bronze bushing
May be part of clutch kit

19. Pilot servicing Should always be changed with clutch
Can be isolated by applying clutch in gear
Special pullers may be used for removal
Can be removed with grease
Should be lightly lubed on installation

20. Clutch linkage Can be operated by cable, rods or hydraulics
May be automatic or manually adjusted
Hydraulic will have a master and slave cylinder
Will use brake fluid for hydraulic action
Will need bleeding with repairs

21. The End