Firebird Power Brake System - Pontiac Grand Prix Service Manual

DELCO-MORAINER POWER
BRAKE
5A-3
CARPET 6 JUTE
YL. 1 BBL. CARB. E
BRAKES
. .
Fig. 5A.3 Firebird Power Brake System
2. Tempest, Grand Prix and Firebird - remove clevis
reaction retainer and O-ring seal from groove on the
and lack nut from push rod. rod.
3. Slowly pull power piston assembly out from the
4. Remove small reaction bumper and air valve SPMg
rear housing, being careful not to damage the power
retainer from air valve- Remove power piston from
piston bearing or push rod boot.
vise.
5. Place square end of tool J 21524 in vise holding
POWER PISTON
-
DISASSEMBLE (Fig. 5A-7)
support plate and power piston with push rod facing
UP.
CAUTION: Care must be taken in handling diaphragm
6. Pull
diaphragm edges away from support plate and
of power piston group. Diaphragm should be guarded
position assembly on tool J 21524 so that three lugs on
against greaseJ oil and foreign matter and must be
tool fit into three notches in power piston (Fig. 5A-10).
protected fiom nicks or cuts that might be caused by
rough surf(u:esJ damaged tools or dropping the piston.
7. Press down on support plate and rotate counterclock-
wise until support plate separates from power piston
1. Place power piston in vise, as shown in Fig. 5A-8.
(Fig. 5A-11).
Remove lock ring from power piston by prying from
under locking lugs. 8.
Remove diaphragm from support plate.
2.
Remove reaction retainer, vacuum cylinder push
9. Remove foam air filter ring from outside of power
rod, reaction plate, three reaction levers and air valve
piston hub.
spring (Fig. 5A-9).
10. Position power piston in vise padded with shop
3.
Remove hydraulic cylinder push rod from center of towels with
hub
end down.