Chevrolet Light Duty Truck 1973 Service Manual page 287

LATCH PLATE T
UPSET FLARE PUNCH
DIE BLOCK\
TUBE
PLATE
Fig. 38--Flaring O peration
DRUM BRAKE ADJUSTMENT
Service Brake
Although the brakes are self adjusting a preliminary or
initial adjustment may be necessary after the brakes
have been relined or replaced, or whenever the length of
the adjusting screw has been changed. The final
adjustment is make by using the self adjusting feature.
1. With brake drum off, disengage the actuator from
the star wheel and rotate the star wheel.
Recommended Method of Adjustment (Fig. 40)
a. Use Drum to Brake Shoe Clearance Gauge
J-21177 to check the diameter of the drum
clearance surface (fig. 40).
b. Turn the tool to the opposite side and fit over
the brake shoes by turning the star wheel until
the gauge just slides over the linings (fig. 41).
c. Rotate the gauge around the brake shoe lining
surface to assure proper clearance.
Alternate Method of Adjustment
a. Using the brake drum as an adjustment fixture,
turn the star wheel until the drum slides over the
brake shoes with a slight drag.
RAM GUIDE
RAM
r
Fig. 41--Setting Lining Clearance w ith J-21177
b. Turn the star wheel 1-1/4 turns to retract the
shoes. This will allow sufficient lining to drum
clearance so final adjustment may be made as
described in Step 3.
2. Install the drum and wheel and remove the vehicle
from the jack stands or hoist.
CAU TIO N:
plate was knocked o u t , be sure a l l metal has
been removed from brake compartment. In st al l
a new metal hole cover t o prevent contamina­
t i o n of the brakes.
Make certain when i nstalling drums that drums
are installed i n the same position as when
Fig. 40--Using D rum -to-B rake Gauge J-21177
If lanced area i n drum or flange
LIGHT DUTY TRUCK SERVICE MANUAL
5-21
BRAKES