Installing Rear Vacuum Seal; Power Piston Assemble; Power Unit Assemble; Gauging Push Rod Length - Pontiac Grand Prix Service Manual

BENDIX POWER BRAKE 5B-5
underneath bore. Torque screw with 318" wrench to 40
lb. in.
7. Install new spring and check valve in both outlet
ports. Press new tube seat into port using spare tube
nut. Torque tube nut to 40 lb. in. to be sure tube seat is
bottomed-in port.
8. Remove master cylinder assembly from vise.
POWER PISTON
-
ASSEMBLE (Fig. 56-4)
1. If rear vacuum seal was removed, place rear housing
on bench with studs down and press new seal carefully
into cavity in housing, plastic side first, using tool J
22677. (Fig. 5B-6) Use hands to press seal about 7/ 16"
below inner housing surface or until metal shoulder
bottoms. DO NOT CRACK PLASTIC.
Fin. 58-6 Installinn Rear Vacuum Seal
. . . .
2. Lubricate outside diameter of diaphragm plate hub,
bearing surfaces of- the valve plunger, and outer edge
they were removed. Lubricate with alcohol for ea$er
of valve poppet with power brake lubricant.
assembly.
3. Insert control valve assembly into diaphragm plate
hub. Push on valve enough to insert the valve plunger
stop key (Fig. 5B-3).
4. Assemble diaphragm on diaphragm plate, making
sure the inner bead of the diaphragm is seated in the
groove in plate.
5. Install silencers over valve operating rod. Be careful
not to chip the plastic.
6. Apply power brake lubricant to seal in rear housing
and around hub of diaphragm plate. Install rear
housing over hub of diaphragm plate.
7. Install large foam air filter and boot. Press boot onto
housing until it bottoms.
8. Coat all surfaces of reaction disc with power brake
lubricant and install disc, button side first, in hub
cavity of diaphragm plate.
9. Apply power brake lubricant to piston end and shaft
of hydraulic push rod and install firmly against
reaction disc in diaphragm plate. DO NOT LUBRI-
CATE ADJUSTING NUT END OF PUSH ROD.
POWER UNIT
-
ASSEMBLE (Fig. 56-2)
1. Coat front vacuum seal with power brake lubricant
and install in cavity of front housing, rubber side
toward master cylinder. Make certain rubber portion
does not separate from metal plate.
2. Install tool J 22805-01 on front housing. Torque
bolts to 25 lb. ft.
4. Place tool J 22805-0 1 in vise with front housing up.
5. Place diaphragm return spring in front housing,
small end down.
e
6. Apply silicone grease or talcum powder to all
surfaces of outer bead of diaphragm that bear against
front and rear housings.
7. Place rear housing assembly over diaphragm return
spring and, using tool J 9504 press down firmly on rear
housing, guiding push rod into front housing seal
making certain scribe marks will align when housings
are locked together. Rotate tool counterclockwise to
lock the two housings. Vacuum may be applied to the
check valve to help draw the housings together.
CAUTION: Do not release pressure on rear housing
until the housings arefully locked.
NOTE: Be sure diaphragm is not pinched during
assembly.
3. Install check valve and grommet in front housing if
Fig. 58-7 Gauging Push Rod Length