Chevrolet 1977 10 Series, Repair Manual, Page: 179 / 468

BRAKES
5-13
Fig. 5-1C-- T y p ic a l P o w e r Brake U n it - E xp lo d e d V ie w
d. Press down on Spanner W rench J-9504 and rotate the
rear housing counterclockwise to unlocked position. Loosen
housing carefully as it is spring loaded.
e. Remove Tools J-9504 and J-22893 from rear housing
(tilted m ounting bracket type): Tool J-9504 on regular type.
4. Lift rear housing and power piston assembly from
unit. Then remove return spring.
5. Remove retaining ring on push rod that holds silencer
in place on push rod; remove silencer.
6. Remove seal and vacuum check valve and grommet
from front housing.
Power Piston Assembly Group (Fig. 5-5C)
CAUTION: Care m ust be used in handling the
diaphragm o f power piston assembly. Guard
diaphragm against grease, oil, foreign matter and
nicks or cuts.
1. Remove power piston assembly from rear housing.
2. Remove silencer from neck of power piston tube.
3. Remove lock ring from power piston by prying one
end out from under large divided locking lug and then
proceed to pull ring from under other two locking lugs on
J -2 2 8 0 5
J-9 5 0 4
Fig. 5-2C--Holding Power C ylinder Using Tool J -2 2 8 0 5
Fig. 5-3C-- S eparating Housings W ith Tool J-95 04