Pontiac FIREBIRD 1972 Service Manual page 502

DISC BRAKES 5E-7
wears too thin the rivets may cut into the rotor and repairs
*
the callper due to rust and corrrosion build up
behind the ~iston. The thickness of the new
will be unnecessarily extensive.
NOTE: Inspect disc brake linings every
6 , m
miles.
In addition, inspect the brake linings any time that the
wheels are removed (tire rotation, etc.). Check both ends
of the outboard shoe by looking in at each end of the
caliper (Fig. 5E-6). These are the points at which the
highest rate of wear normally occurs. However, at the
same time, check the lining thickness on the inboard shoe
to make sure that it has not worn prematurely. Look down
through the inspection hole in the top of the caliper to
view the inboard shoe. Whenever the thickness of any
lining is worn within 1/8" of the metal shoe, all shoe and
lining assemblies on both sides should be replaced.
NOTE: Wheel inust be removed to inspect lin-
ing.
SHOE AND LINING REPLACEMENT
NOTE: When replacing shoe and lining assem-
blies on disc brake vehicles after mileage ac-
cumulation it is sometimes necessary to rebuild
Fig. 5E-6 Lining Inspection
linings forces the piston back into the rusted
areas which may cause the piston to stick in the
bore.
CALIPER
REMOVE
1. Remove two thirds of the total fluid capacity from
the front master cylinder reservoir. This may be done
by breaking the front line connection at the master
cylinder and bleeding down the fluid level. Do not
remove the brake line or completely empty the reser-
voir or it will be necessary to bleed the hydraulic
system. Discard
--
do not attempt to reuse
--
the
brake fluid removed.
NOTE: Removal of the fluid is necessary topre-
vent reservoir overflo w when the caliper piston
is pushed back in its bore during lining replace-
ment.
2. Raise the car and remove the wheel covers and wheel
assemblies.
Fig. 5E-7 Removing Mounting Bolts