Pontiac FIREBIRD 1972 Service Manual page 486

TANDEM DIAPHRAGM POWER BRAKE-MORAINE 5D-9
Fig. 5D-7 Tools for Disassembly of Power Brake Housing
Fig. 5D-8 Separating Front and Rear Shells
be protected from nicks or cuts that might be
caused by rough surfaces or damaged tools.
Lift bead on O.D. of secondary diaphragm and
remove diaphragm support ring.
Remove piston rod retainer and piston rod from sec-
ondary piston.
Mount double-ended tool J 23 101 (with large diame-
ter end up) in a vise. Position the secondary power
piston so that the two radial slots in piston fit over
ears of tool (Fig. 5D-1).
Fold back primary diaphragm from O.D. of primary
support plate. Grip edge of support plate with hands
and rotate counterclockwise to unscrew primary
power piston from secondary power piston. (Fig. 5D-
11).
NOTE: It is possible that the primary support
plate will unlock from the primary piston
before the primary piston unscrews from the
secondary piston. If this happens, continue to
turn primary support plate counterclockwise.
Tabs ("Stops'3 on primary support plate will
temporarily lock primary support plate to pri-
mary po wer piston and permit continued coun-
terclockwise rotation to unscrew primary
PO
wer piston from secondary power piston.
Remove housing divider from secondary power pis-
ton. Remove secondary power piston bearing from
housing divider.