Pontiac tempest 1968 Service Manual page 206

H E A V Y D U T Y POWER BRAKES
5 C - 3
Fig. 5 C - 2 V a l v e Rod,
2. Place assembly in arbor press (Fig. 5C-3A)
with rear shell and spanner wrenches up
0
Secure
tool J-8433 to press to prevent tilting of front shell.
3. Compress assembly sufficiently enough to allow
rotation of tools J-9504.
CAUTION: Do not compress assembly to the point
of damaging power unit.
4. Scribe a mark across front and rear shell to
facilitate assembly.
5. Rotate spanner wrenches (J-9504) counter­
clockwise to release position (to point where cutouts
J 2 2 5 5 3 - 1
J 8433
J 9 5 0 4
J 6 4 0 7 - 2 1
F i g . 5 C - 3 Power Unit Special Tool Combination
liners, Filters and Poppet
in front shell are in line with lances in rear shell).
6. Slowly release pressure on assembly.
CAUTION: Diaphragm return spring is under
pressure. Use care in separating shells to avoid
the spring flying out.
REMOVAL OF REAR SHELL VACUUM SEAL (Fig.
5C-JJ
Place rear shell on bench with studs up and drive
out seal with punch or screwdriver.
NOTE: Do NOT remove rear seal unless seal is
defective.
DIAPHRAGMS, PLATES, RETAINER AND PLUNGER-
REMOVE (Fig. 5C-4)
Wet rear diaphragm spring retainer with alcohol
and remove, using fingers only. Remove rear dia­
phragm from rear plate. Set 1-1/16" hex bar stock
about 2 " long or tool J - 2 2 8 3 9 in bench vise. Set
Diaphragm and Plate assembly on hex stock with hex
opening in center of front plate on bar. Twist rear
plate counterclockwise, using hand leverage only
either on atmospheric pressure channel or on out­
side circumference of rear plate.
After plates have been loosened, remove assembly
from vise and complete disassembly on bench, front
plate down. Unscrew rear plate completely and care­
fully lift it off front plate hub, grasping valve plunger