Porsche 928 - WORKSHOP MANUAL 1977 Workshop Manual page 238

47
Brakes, Hydraulics, Regulator, Booster
928
6. Remove the master brake cylinder at its
flange with a l/4-inch ratchet, a 13 mm
socket wrench insert and a suitable exten
sion. Take out the master brake cylinder.
I
I
On right-hand drive cars, the windshield
washer filler pipe must also be removed. Take
it out at the same time as the master brake cyl-
inder.
Installing
1. Renew the O-ring between the master brake
cylinder and the brake booster, or else a
loss of vacuum may occur.
2. Install the master brake cylinder and con-
nect up the brake pipes.
3. Press the fluid reservoir into the sealing
plugs in the master brake cylinder. Use new
sealing plugs each time the fluid reservoir is
removed. When pressing in, the reservoir
must pass 2 detents before firm seating can
be guaranteed.
Note
Use only brake fluid or brake cylinder paste as
an aid to installation. Substances containing
mineral oil will destroy the rubber elements in
the brake system and cause brake failure.
In the case of stepped brake master cylinders,
there is a washer under the front sealing plug
(intemediate piston brake circuit).
4. Bleed the brake/clutch with the filling and
bleeding device. Check for leaks and for cor-
rect operation.
47- 14
Removing and installing the master brake cylinder
l
Printed in Germany - Xxv. 1990