Cadillac 60 Series 1963 Shop Manual page 185

8-20
BRAKES
Fig. 8-27 Power Piston Diaphragm Installed in Power Unit
NOTE: When locating diaphragm support
plate on power piston, be sure reaction levers
maintain their positions in seats in power piston
insert.
23. Install three special hex head screws that
hold power piston to support plate. Torque screws
to 60 inch-pounds, Fig. 8-24.
NOTE: Press in on air valve and push rod
assembly to make certain it is under spring
tension and that reaction levers have not be-
come mispositioned.
24. Install filter retainer on push rod, wrap flat
piece of filter material around push rod and press
down into power piston tube.
25. Install master cylinder on front shell of
power unit and install two lockwashers and nuts
finger tight, Fig. 8-22.
26. Clamp master cylinder in vise with front
shell up.
27. Install power piston return spring so that it
seats over support plate seal retainer.
28. Lightly lubricate tube extension on master
cylinder end of power piston and tube extension
on push rod end of power piston with special
lubricant.
29. Lightly cover oval lip of diaphragm with
talcum powder.
Push Rod Height
Gage J-7723-01
Fig. 8-28 Checking Push Rod Height (Delco Moraine)
30. Insert power piston, push rod first, into
rear shell of power unit. Extension on end of
power piston fits through power piston bearing
seal and push rod through silencer and dust guard.
31. Fold diaphragm back into position on rear
shell flange.
32. Install rear shell and power piston assem-
bly into front shell. Align scribe marks on shells
so that when shells are rotated into locked po-
sition, scribe marks will line up.
33. Install Power Unit Shell Separator, J-9504,
over mounting studs on rear shell and press rear
shell into front shell making certain that oval lip
of diaphragm is correctly positioned between
edges of front and rear shells. Rotate rear shell
clockwise to lock shells together.
NOTE: Master cylinder push rod is designed
with a self-locking adjustment screw to provide
the correct relationship between vacuum piston
and master cylinder piston. This adjustment is
very important because it assures the compen-
sating port being kept open while unit is in r e -
leased position. Adjustment screw is set to
correct height at time of assembly and, under
normal service, will not require further ad-
justment. When unit has been disassembled,
however, adjustment should be checked to as-
sure proper height.
34. Place power brake assembly on bench with
master cylinder up and remove master cylinder
and support plate seal retainer.
35. Place Push Rod Height Gage, J-7723-01,
over push rod with legs of gage resting on front
shell of vacuum power unit, Fig. 8-28. Top of
screw should just touch gage.
36. If adjustment is necessary, turn adjusting
screw either in or out as required.
37. Install support plate seal retainer into front
shell so that gasket is between flange on retainer
and surface of front shell, Fig. 8-22.
38. Install master cylinder on vacuum power
unit and secure with two lockwashers and nuts.
Torque to 17 foot-pounds.
19. Delco Moraine Master Cylinder
Disassembly, Cleaning, Inspection
and Assembly
a. Disassembly
NOTE: If trouble has been traced to hydrau-
lic system, master cylinder may be removed
from vacuum unit without removing complete
power brake assembly from car. Area sur-
rounding master cylinder mounting surface must
be kept clean.