Mechanical Brake Linkage; Mechanical Park Brake Adjustment; Brake And Park Brake Adjustment - Columbia ParCar P4G Service Manual

2. Remove brake drums. For brake drum removal, it may
be necessary to retract the brake shoes. The brake
adjuster can be accessed through an inspection open-
ing in the back side of the brake drum.
3. Inspect drum for excessive or uneven wear. Maximum
drum inside the diameter equals 6.635 inches (168.4
mm). If drum is worn beyond service limit or uneven
wear is observed, drum must be replaced.
4. Inspect brake shoes for thickness, uneven wear or
physical damage. If brake shoe lining, at any point, is
measured to be less than 1/16 inch (1.6 mm), brake
shoes must be replaced. Also, inspect for oil or grease
contamination, and replace brake shoes if contamina-
tion is present.
5. Wash mud, brake shoe debris, and dirt from brake
assemblies and drum. Apply white lithium grease to
contact points between brake shoe and brake back
plate. Remove excess grease to prevent brake shoe
contamination.
6. Install brake drum. Torque axle nut to minimum 65 ft.
lbs. Tighten additionally, as required, to align cotter pin
slot with cotter pin hole in axle. Install cotter pin and
bend ends to secure axle nut.
7. Install rear wheels. Lightly torque four lug nuts evenly.
Then, retorque in criss-cross fashion to 65 to 70 ft. lbs.
8. Inspect dust boot at brake actuating lever. If cracked
or split, replace dust boot.
Adjustments

Mechanical Brake Linkage

Note: Correct rear brake operation should be confirmed
before adjustments are made to cables and mechanical
linkage. Also, check to ensure corrosion has not caused
excessive resistance in the operation of brake cables
before cable and linkage is adjusted.
Depress brake pedal. If pedal travels in excess of 2
inches, adjustment of linkage and cables will be required.
1. Locate, under the vehicle, the brake rod connecting
brake pedal to brake equalizer. Loosen jam nuts at
each end.
2. Rotate brake rod to shorten the length from brake
pedal to equalizer.
3. Adjust length of brake rod until free brake pedal move-
ment is less than 1/4 inch.
4. Secure jam nuts to prevent rod from rotating.
Note: Excessive brake rod and cable tension could cause
automatic adjusters in the rear brakes to become
inoperative.

Mechanical Park Brake Adjustment

Once the rear brake operation has been confirmed and
brake linkage and cables have been adjusted, the park
brake adjustment can be checked and corrected if
necessary.
1. View down through the opening of the floor board
while gently pressing on the brake pedal pad. As you
press on the brake pedal pad, observe the space or
gap between the brake ratchet end and the brake
ratchet pawl (Figure 2). This gap should be no greater
than 1/8 inch and no less than 1/16 inch.
Park
Brake Rod
(Adjustable)
A
B
1/16 To 1/8"
Figure 2 - Brake and Park Brake Adjustment
2. If adjustment is required, remove the clevis pin from
the park brake pad, securing the park brake rod. This
threaded rod can be lengthened or shortened to
adjust its length. If the observed gap between the park
brake ratchet and the park brake pawl is less than
1/16 inch, the rod must be shortened slightly to adjust.
If the gap between the park brake ratchet (A) and the
park brake pawl (B) is in excess of 1/8 inch, the park
brake rod should be lengthened to adjust.
3. Reconnect the park brake rod to the park brake pad or
pedal. Recheck space between park brake ratchet
and park brake pawl to verify correct gap of 1/16 to 1/8
inch.
4. Depress the park brake pedal, and push pedal
assembly down until the first click is heard. At this set-
ting, the vehicle should not roll on a slight incline.
Depress the park brake pedal down to the second
click or notch. With the park brake set at the
second click or notch, the vehicle should not roll on a
steep incline or hill.
4-2
Press Down
Approx. 1"
(24.5 mm)
Brake
Rod
Equalizer
Brake
Cable