1. Clutch Slip
2. Non Clearance, difficulty in engaging gears, clutch fails to release.
3. Vibrant Clutch
4. Noisy Clutch
1. Clutch Slip
1. Incorrect adjustment/setting of release mechanism.
2. Clutch worn out (usually Drive Plate facing worn thin).
3. Oil contamination, gearbox or crankshaft oil seals are defective.
4. Faulty Cover Assembly, e.g. broken or weak diaphragm spring.
5. Excessive amount or Incorrect type of spline grease applied to the spline shaft when fitting the clutch.
6. Incorrect Cover Assembly fitted, i.e. underrated for application.
7. Poor driving technique, i.e. resting foot on clutch pedal.
8. Clutch abuse causing facing materials to overheat impairing their frictional value.
9. Loss of clamp force due to wear in the flywheel face.
2. Non Clearance, difficulty in engaging gears, clutch fails to release.
1. Release mechanism not set correctly.
2. Clutch pedal travel impeded.
3. Wear in release mechanism or air in hydraulic type system.
4. Drive plate distorted, (damaged in transit or during fitting).
5. Fault in cover assembly. eg loose or broken fulcrum ring, weak drive straps.
6. Spigot bearing/bush seized (where applicable).
7. Drive plate or primary shaft spline damage.
8. Release bearing/fork retention clips faulty.
9. Oil contamination prevents driven plate releasing from the flywheel or cover assembly pressure plate.
10. Excessively worn or stretched release cable, such that the auto adjust mechanism is not capable of achieving the correct setting.
3. Vibrant Clutch
1. Operation of cover assembly faulty.
2. Action of the release bearing Is incorrect.
3. Worn clutch components.
4. Worn vehicle components, i.e. engine or transmission mountings, transmission couplings, suspension components.
5. Sticking or worn release mechanism.
6. Cover assembly pressing distorted during fitting.
7. Corrosion, damage or wear of drive plate spline or gearbox spline shaft.
8. Grooved fly wheel.
9. Oil contamination.
4. Noisy Clutch
1. Release bearing noisy, (continuous) or can be intermittent upon operation of clutch.
2. Noise generated on operation of clutch due to over adjustment.
3. Worn damper system in driven plate.
4. Release bearing not running centrally.
5. Release bearing running dry/loss of bearing grease due to overheating.
6. Release bearing running on uneven diaphragm fingers.
The above is not an exhaustive list of clutch faults, others may be encountered which are peculiar to particular vehicle types.