Check operation of the power steering every 60000 km (40000 miles).
A) Vane type pump
If the power steering develops a fault, always check first the supply pressure
form the high pressure pump.
Detach pressure line (A) from the high pressure pump and conect to pressure
gauge 7017.
Connect pressure line (B) to the high pressure pump.
Close the stop valve (1).
Open stop valve (2) - lever must be horizontal - and bleed the hydraulic system
32 13 006). Engine at idle speed.
The engine must first reach normal operating temperature. After bleeding is
complete, close stop valve (2) for max. 10 seconds - lever vertical - and read off
the pressure on the gauge.
Pressure should not be more than 10% below the value stated on the maker`s
plate of the high pressure pump.



32 13 006

If the correct pressure is not reached:
a) Check V-belt tension.
b) Examine valve piston for dirt, and replace if necessary.
Warning: Install only a valve piston of the same tolerance group
as before. The threaded section of the valve piston should face the coil spring.

If the maximum pressure is still not reached, replace the pump rotor, vanes
and cam disc as a unit.

B) Hydraulic power steering
Raise the vehicle.
Block the steering with the steering wheel 1/2 to 3/4 of a turn before the full
lock position (using a socket head or similar object).

Pull the steering wheel for approx. 5 seconds towards the end stop with a
force of 10 kp (22 lb)
Read off pressure on pressure gauge 70 17.
Repeat the measurement at the oppsite lock position.
If the pressure thus recorded are below the max. pump pressure:
a) the high pressure pump is delivering too little oil
b) the steering is losing oil through leakage
c) the steering box seals are damaged
d) the valve piston is contaminated
e) the valve piston is not closing correctly
f) the steering limit valve is not closing.

C) Mechanical play in steering - checking
(pressure point correctly adjusted)
Lock the steering drop arm in the straight ahead position of the wheels with
70 16 locking device.

Open the stop valve (2).
Close valve (1).
Run the engine at normal operating temperature and idle speed.
Open valve (1).

Attach strips of paper to the steering wheel hub and the upper section of the
housing.
Carefully turn the steering wheel to the left until the pressure gauge indicates
a rise of 1 atü (14.2 psi) over the normal supply pressure. Mark this position of the
steering wheel at (A).
Carefully turn the steering wheel to the right until the pressure gauge again
shows a rise of 1 atü (14.2 psi) over the normal supply pressure. Mark this position
of the steering hub at (A).
The total distance between the two markings must not exceed 7 mm
(0.276 in.). If this distance is exceeded, check joint disc and universal joint. If
these components are found to be serviceable, the steering box must be taken
down.
Remove pressure gauge 70 17, add oil to the hydraulic system and bleed.