Chevrolet 1980 Light Duty Truck Service Manual page 389

PARKING BRAKE STRUT
STRUT SPRING
ADJUSTER LEVER
ACTU ATING LINK
SPRING & CUP
BRAKE SHOE RETURN SPRING
5. Spread shoes to clear wheel cylinder connecting
links, remove parking brake strut and spring, disconnect
cable from parking brake lever, remove shoes from the
backing plate.
6. Separate the brake shoes by removing adjusting-
screw and lock spring. Remove parking brake lever and
secondary brake shoe.
7. Clean all dirt out of brake drum. Inspect drums and
replace or recondition if required.
8. Clean all dirt from brake assemblies and inspect for
any unusual condition.
9. Wheel cylinders having torn, cut, or heat-cracked
boots should be completely overhauled.
Inspection for leakage may be accomplished at the boot
center hole after removal of link pin. Fluid coatings on
piston within cylinder and on end of link pin removed from
boot are normal, as cylinder contains a porous PISTON
WHICH IS IMPREGNATED WITH A CORROSION
INHIBITING FLUID. Fluid spilling from boot center
hole, after link pin is removed, indicates cup leakage and
necessity for completely over-hauling cylinder.
10. Inspect backing plate for oil leakage past wheel
bearing oil seals. Correct any leak by installation of new
seals (See Section 4B).
11. Check all backing plate attaching bolts to make sure
they are tight. Using fine emery cloth, clean all rust and dirt
from shoe contact surfaces on plate.
WHEEL CYLINDER LINK"
SECONDARY SHOE & LIN IN "
SHOE GUIDE
/
/
'— HOLD DO W N SPRING
ADJUSTING SCREW SPRING
ADJUSTING SCREW
— VER RETURN SPRINGS
Fig. 5 -4 4 -T y p ic a l Drum Brake Assem bly
In s ta lla tio n and A d ju s tm e n t
Delco Brake Lubricant or equivalent, then attach lever to
secondary shoe. Make sure that lever is free moving.
spring, then place adjusting screw in position. When
installing the adjusting screw spring and adjusting screw,
WHEEL CYLINDER SCR"" " '
HOLD DO W N PINS
PARKING BRAKE LEVER
\ '— WHEEL CYLINDER
V— RY SHOE AND LINING
p r i m a
1. Lubricate fulcrum end of parking brake lever with
2. Connect brake shoes together with adjusting screw
Fig. 5 -4 5 -M e a s u rin g Brake Drum I.D.
BRAKES 5-35
L IG H T T R U C K SER V ICE M AN UAL