Clutch: design, wear, replacement
Why a 944 clutch change is a big job, how to measure wear without removal and what to replace at the same time.
In short: The clutch sits at the front on the engine, the gearbox at the rear. To replace it, the transaxle and torque tube have to come back – hence the long labour time. Wear, however, can be measured without removing anything.
Design
The clutch consists of one disc, a pressure plate carrying the starter ring gear, and a release bearing with lever in the clutch housing. A pilot bearing sits in the end of the crankshaft.
Measuring wear
Through an inspection port on the left of the clutch housing you measure the distance to the slave cylinder piston. New, it is about 18 mm; from 34 mm the disc needs replacing. On the Turbo a heat shield often blocks the view.
Symptoms
A high or heavy biting point is a sign of a worn clutch; a soft or sinking pedal points to leaking master or slave cylinders.
Replace at the same time
Recommended: the pressure plate, release bearing, pilot bearing and the release lever needle bearings, plus new bolts. If the flywheel is resurfaced, the rear crankshaft seal belongs on the list too.
We deliberately do not give tightening torques here – they are in the workshop manual.
Technical values
Only work with the workshop manual and the correct tools. Do not use unverified values without checking them – wrong tension values can destroy the engine.
| Value | Figure | Condition | Status | Source |
|---|---|---|---|---|
| Clutch wear dimension, new (inspection port to slave piston) | about 18 mm | – | unverified | [2] |
| Clutch wear dimension: replace from | 34 mm | – | unverified | [2] |
| Check interval | at least every 15,000 miles | – | unverified | [2] |
| Labour time, clutch change 944 | 16 hours | – | unverified | [1] |
| Labour time, clutch change Turbo | 20 or 24 hours (depending on crossover pipe) | – | unverified | [1] |
Sources
- Secondary source Clutch Replacement
Clutch design and removal, labour times.
- Secondary source Clutch Disc Wear Check
Wear check through the inspection port on the clutch housing.
- Secondary source Porsche 944 buying checklist (PDF)
Buying checklist ordered by area.