Pressure Tests On The Lock Hydraulics (Energy Production); Overview/General; Pressure Gauge Connection - Porsche 928 Workshop Manual

39
Differential, transaxle system
928
Pressure tests on the lock hydraulics (energy production)
Overview
1. Genera
2. Pressure gauge connection
3. Tests
4. Nominal values/Notes
1. General
The following points can be checked by
means of the pressure test on the differential
lock hydraulics (lock control):
- Freedom from leaks of the lock hydraulics
(any internal leak can thus be localized)
- Gas filling pressure of the pressure reservoir
- Switching points for the lock hydraulics (di-
splay "PSD off" and operating pressure).
This is controlled by the pressure warning
switch of the pump assembly.
- Connect pressure gauge 9509 - in combina-
tion with the high-pressure measuring line
9509/l (No.~), ring connection (No. 3). ban-
jo bolt (No. 4) and two seal rings (No. 5) -
at the lock solenoid valve instead of the
bleeder valve.
Important:
Machine ring connection (No. 3)
beforehand (apply face/arrow).
2. Pressure gauge connection
- Depressurize the lock hydraulics. To do
this, disconnect the electrical plug at the
pressure pump (pump assembly) and then
relieve the pressure at the pressure relief
valve of the lock solenoid valve (use a col-
lection bottle).
Important:
Wear goggles and protective
gloves, as the pressure may be as high as
180 bar.
i
L
D39 - 252
a
PSD diagnosisfkoubleshooting
Printed In Germany - XXXV, 1995