Diagnosis of clutch system faults (Mercedes-Benz C-Class W202)

Diagnosis of clutch system faults

Cause	Method of elimination
The clutch is jerking
Engine shaft speed is too low in idle mode	Check the engine speed control system in idle mode.
The engine shaft bearing and gearbox shaft bearing are faulty	Check and replace if necessary.
The pressure plate does not fit evenly	Replace the pressure plate.
Non-branded clutch disc	Install the original clutch disc.
The clutch is slipping
The clutch disc is worn out	Check the thickness of the clutch disc, replace the clutch disc if necessary.
The clutch pedal limit stop is faulty	Check the clutch pedal limit stop.
Disc spring tension too low	Replace the pressure plate.
The distributor cylinder is jammed	Replace the distributor cylinder.
The distributor cylinder is leaking	Perform a visual inspection.
The friction lining has hardened and become oily	Replace the clutch disc, eliminate the cause of contamination.
The clutch was overheated	Install original parts.
The clutch does not disengage correctly
The sensor cylinder is leaking	Check the sensor-cylinder, have the pedal depressed and check if the liquid in the receiver has boiled.
Air in the clutch system	Bleed the clutch control drive.
The clutch pedal does not reach the limit stop	Check the clutch pedal stop, cut the mat if necessary.
The friction lining sticks due to wear	Replace the clutch disc.
The clutch disc is seizing on the primary gearbox, the fine-spline connection is dry or sticking	Clean the fine spline connection, remove burrs, remove rust if necessary.
The clutch disc has lateral runout	Have the clutch disc checked and replaced if necessary.
The gearbox input shaft centering bearing on the crankshaft is faulty	Replace the centering bearing on the crankshaft.
Difficulty rotating clutch release bearing or heavy pedal travel	Replace the clutch release bearing, the pedal should be pressed easily.
The clutch pedal does not return back or returns with delay
Air in the clutch system	Bleed the clutch control drive.
Old (oxidized) brake fluid	Replace the brake fluid.
The distributor cylinder or sensor cylinder is stuck	Replace the distributor cylinder or sensor cylinder.
The clutch disc is worn out	Replace the clutch disc.
Due to overheating, the clutch pressure plate was damaged, which weakened the force of its return to its original position	Replace the pressure plate.
Noise is heard when the clutch pedal is depressed
The clutch release bearing is faulty	Check the clutch release bearing and replace if necessary.
Clutch disc hits pressure plate	Replace the clutch disc.
Waxing and fading noise when pushing or towing, or if the vehicle is rolling with the clutch engaged
Difficult movement of the clutch disc vibration damper	Restore the clutch disc or replace it.
The coupling rivet joints are loose	Replace the coupling.
Too much clutch imbalance	Replace the clutch and disc.