Parking Brake-Propeller Shaft; Foot Pedal Type; Orscheln Lever Type - Chevrolet 10 1971 Series Chassis Service Manual

Fig. 47— Parking Brake Handle P— 10 Series
The propeller shaft parking brake used on all other
trucks operates independent of the service brakes and
necessary adjustment is covered in this section,,

Foot Pedal Type

1. Jack up both rear wheels.
2. Apply parking brake 1 notch from fully released
position.
3. Loosen equalizer check nut and tighten the adjusting
nut until a moderate drag is felt when the rear
wheels are rotated.
4. Tighten the check nut securely.
5. Fully release parking brake and rotate the rear
wheels. No drag should be present.

Orscheln Lever Type

1. Turn adjusting knob on parking brake lever counter­
clockwise to stop.
2. Apply parking brake.
3. Jack up both rear wheels.
4. Loosen lock nut at intermediate cable equalizer and
adjust front nut to give light drag at rear wheels.
5. Re-adjust parking brake lever knob to give a definite
snap-over-center feel.
6. Fully release parking brake and rotate rear wheels.
No drag should be present.

PARKING BRAKE-PROPELLER SHAFT

Internal Expanding (Fig. 49)
Adjustment— Drum On
1. Jack up at least one rear wheel. Block wheels and
release hand brake.
2. Remove cotter pin and clevis pin connecting pull rod
and relay lever. This will assure freedom for full
shoe release.
It may be necessary to knock out lanced
NOTE:
area in brake drum with punch and hammer to
Fig. 48— Parking Brake Handle P-20-30 Series
gain entry into adjusting screw through brake
drum. Be sure all metal has been removed from
parking brake compartment.
3. Rotate brake drum to bring one of access holes into
line with adjusting screw at bottom of shoes.
4. Expand shoes by rotating adjusting screw with screw
driver inserted through hole in drum. Move outer
end of screw driver away from drive shaft. Continue
adjustment until shoes are tight against drum and
drum cannot be rotated by hand. Back off adjustment
ten notches and check drum for free rotation.
5. Place parking brake lever in fully released position.
Take up slack in brake linkage by pulling back on
cable just enough to overcome spring tension. Adjust
clevis of pull rod or front cable to line up with hole
in relay levers.
a. Insert clevis pin and cotter pin, then tighten
clevis locknut.
b. Install new hole cover in drum to prevent con­
tamination of brake.
c. Lower rear wheels.
blocks.
Adjustment— Drum Off
1. With parking brake drum off, use special Tool J-21177
or J-22364, Drum to Brake Shoe Clearance Gauge, to
check diameter of drum clearance surface.
2. Turn the tool to the opposite side and fit over brake
shoes by turning the star wheel until the gauge just
slides over the linings.
3. Rotate the gauge around the brake shoe lining surface
to insure proper clearance.
4. Install propeller shaft flange at mainshaft as outlined
in transmission section.
5. Lower rear wheels. Remove jack and wheel blocks.
Removal (Fig. 49)
1. Remove the propeller shaft. See Section 4.
2. Remove the brake drum.
It may be necessary to back off the shoe
NOTE:
adjustment before removing the drum.
3. Remove the two pull back springs,
4. Remove the guide plate from anchor pin.
5. Remove shoe hold down cups, springs, and washers
from hold down pins - remove pins.
BRAKES 5-23
Remove jack and wheel
10-30 CHEVROLET TRUCK SERVICE MANUAL