Chevrolet 1973 Overhaul Manual page 133

5 -3 0 BRAKES
Fig. 7D -Installing Rear Housing Seal w ith Installer
J-22677
24.
Clevis Type Push Rod
to push rod end.
25. Dip check valve grommet in denatured alcohol and
install into front housing, beveled side first.
26. Dip end of vacuum check valve in denatured
alcohol and install valve through grommet.
27. Apply Delco Silicone Lube #5459912 (or equiv­
alent) to piston end of piston rod and insert in
cavity in front plate. Twist rod to eliminate air
bubbles at reaction disc. Assemble seal over piston
rod and press into recess in front housing.
Fig. 8D--Seal Protector J-22733 Installed
- Assemble locknut and clevis
AIR VALVE
PLUNGER
Fig. 9 D -In s ta llin g A ir Valve Assembly
The piston rod is designed with a
CAUTION:
self-locking adjustment screw to provide the
correct relationship between vacuum piston and
master cylinder piston. The adjustment is
important as it provides fo r the compensating
port being kept open while unit is in released
position. Adjustment screw is set to the correct
height when assembled, and under normal
service, will not require further adjustment.
After unit has been disassembled however, the
height should be checked as follows.
Piston Rod Gauging
If adjustment is necessary, grasp piston rod with pliers at
FRONT PIAPHRAGMTlJRETAlNER
Fig. 1 0 D -In s ta llin g Rear D iaphragm Retainer
REAR PLATE
1
[REAR DIAPHRAGM
[CENTER PLATE
OVERHAUL MANUAL