Checking clutch master cylinder and clutch slave cylinder — AUDI

Checking clutch master cylinder and clutch slave cylinder
Before you renew the clutch master cylinder or slave cylinder you must - in the case of the following faults - first carry out the appropriate checks.
Noises when operating the clutch:
First check whether any noise is coming from the over-centre spring.
If you hear any noise, remove the over-centre spring and check again.
Renew the affected component.
After releasing clutch pedal it still remains depressed / does not return to its initial position.
Check whether the clutch pedal returns all the way to its initial position, thereby uncovering the vent opening in the master cylinder.
Check that footwell trim and/or floor mats are not trapped.
Make the customer aware that the driver must not rest his/her foot on the clutch pedal when not using it.
This could impair the self-bleeding function of the hydraulic clutch system as the vent opening in the clutch master cylinder can no longer function.
The vent opening must be uncovered, otherwise the permanent self-bleeding function for the hydraulic clutch system will no longer be effective.
The vent opening is integrated in the clutch master cylinder and cannot be seen from the outside.
Checking entire hydraulic system for leaks
Check brake fluid level in brake fluid reservoir.
Check clutch master cylinder and slave cylinder as well as the pipe/hose assembly including connections for external leaks (visual inspection).
If you identify any leaks you must renew the leaking component.
Bleed clutch hydraulics
Chapter
.
High pedal force:
In the event of a mechanical fault on clutch plate or pressure plate, refer to
Servicing 6-speed manual gearbox 0CS, 0DJ, 0CX
Rep. gr.
30
Clutch; Exploded view - clutch
.
Pedal forces:
- approx. 140 N for complete service life of the clutch
Clutch does not disengage or does not disengage fully:
Air in hydraulic system: bleed clutch mechanism
Chapter
and check hydraulic system for external and internal leaks.
Clutch plate does not move smoothly on input shaft splines.
Needle bearing in drive plate defective (centring bearing for input shaft); renew needle bearing
Engine, mechanics
Rep. gr.
13
Cylinder block (gearbox end); Renewing needle bearing in drive plate
.
Foreign body in clutch system
In the event of a mechanical fault on clutch plate or pressure plate, refer to
Servicing 6-speed manual gearbox 0CS, 0DJ, 0CX
Rep. gr.
30
Clutch; Exploded view - clutch
.
Wrong components installed when carrying out repair work (e.g. clutch plate, clutch pressure plate and dual-mass flywheel are not from the same manufacturer); for correct version refer to
Electronic parts catalogue
.
Components were forgotten when carrying out repair work (e.g. intermediate plate or dowel sleeves between engine and gearbox).
Clutch plate was installed incorrectly when carrying out repair work.