Chevrolet 1977 10 Series, Repair Manual, Page: 181 / 468

BRAKES
5-15
REACTION
PLATE
REACTION
RETAINER
REACTION
LEVERS
POWER PISTO
Fig. 5-7C --R e m o vin g R e a ctio n R e ta in e r
5. Place power piston W rench J-21524 with square
shank in vise. H old support plate and power piston with tube
o f power piston up (fig. 5-8C).
6. Pull diaphragm edges away from support plate so
hands can grip steel support plate. Position assembly on
power piston W rench J-21524 so three lugs on tool fit into
three notches in power piston (fig. 5-9C).
7. Press down on support plate and rotate
counterclockwise until support plate separates from power
piston (fig. 5-IOC).
SUPPORT PLATE
\ -----
s -
D IAPH R AG M
Fig. 5 -9 C -P o s itio n in g P o w e r P iston on S u p p o rt Plate R em over
8. Remove diaphragm from support plate and lay both
parts aside.
9. Position power piston, tube down, in a tool, fabricated
from a piece of wood
2"
x 4" x 8" long with a 1-3/8" hole
in center, clamped in a vise. D o not clam p tube in vise.
10. Use Snap Ring Pliers J-4880 to remove snap ring on
air valve (fig. 5-11C).
11. Set up Power R am and H ydraulic Pum p with J-9746
Press Plate. Insert power piston, tube down, in press plate
and remove air valve assembly using a 3 /8 " drive extension
as a remover (fig. 5-12C).
12. Removal o f air valve-push rod assembly disassembles
the following parts from power piston: floating control valve
assembly, floating valve retainer, push rod limiter w asher and
air filter.
SUPPORT
PLATE
PISTON
SUPPORT PLATE
REMOVER A N D
INSTALLER J-21524
Fig. 5-8C--Positioning S up po rt Plate Retainer in Vise Fig. 5-10C--Removing S upport Plate