Porsche 928 Workshop Manual page 230

Differential. Transaxle Svstem
928
Procedure
Refer to page D39-213 for a listing of
the actual values (admissible locking
values) vs. the corresponding
pressures.
Possible causes for deviation from
specification
- Test requirements not met.
Example: RH rear wheel not fully
locked, pressure gauge and lock
hydraulics not properly bled.
- Faulty discs
Hydraulic pressure does not become
effective to the degree indicated at
the discs, e.g. due to faulty setting of
the mating bearing screw of the en-
gaging lever (engaging lever rides).
Execution / Notes
When measuring the breakaway torque, measure at
several locations (angular positions) within one wheel
revolution.
After the actual locking torque has been reached,
immediately read off the pressure at the pressure
gauge. Record both actual values
(torque + pressure).
- Measurement 2 = Gauge pressure IO...20 bar
Use the System Tester to build up test pressure,
applying a corresponding number of pulses.
Set torque wrench to bottommost value (depending
on pressure) according to boundary value window
(p. 039.213).
Repeat process as described for measurem. no. 1.
- Measurement 3 = Gauge pressure 20...40 bar.
Repeat process as described for measurements
1 and 2. respectively.
- Compare actual values obtained in measurements
l/2/3 with values specified on p. D39-213.
039 - 210
PSD-Diagnosis / Troubleshooting
a
Printed in Germany - XXVII, 1991