Drum Brake System: Service and Repair

REMOVAL





1. INSPECT SHOE LINING THICKNESS
Remove the inspection hole plug, and check the shoe lining thickness through the hole.
If less than the minimum, replace the shoes.
Minimum thickness: 1.0 mm (0.039 inch)

2. REMOVE REAR WHEEL





3. REMOVE BRAKE DRUM

HINT: If the brake drum cannot be removed easily, do the following steps.

a. Insert a bent wire or equivalent through the hole in the brake drum, and hold the automatic adjusting lever away from the adjuster.
b. Using a screwdriver, reduce the brake shoe adjustment by turning the adjuster.
4. REMOVE FRONT SHOE





a. Using SST, disconnect the return spring.
SST 09703-30010





b. Using SST, remove the shoe hold-down spring, 2 cups and pin.
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c. Disconnect the anchor spring from the front shoe and remove the front shoe.
d. Remove the anchor spring from the rear shoe.





5. REMOVE REAR SHOE
a. Using SST, remove the shoe hold-down spring, 2 cups and pin.
SST 09718-00010
b. Using a screwdriver, disconnect the parking brake cable gram from the anchor plate.
c. Using needle-nose pliers, disconnect the parking brake cable from the lever and remove the rear shoe with adjuster.

NOTICE: Do not allow oil or grease on the rubbing face.

6. REMOVE ADJUSTER FROM REAR SHOE
a. Remove the adjuster with the return spring.





7. REMOVE AUTOMATIC ADJUSTING LEVER AND PARKING BRAKE LEVER
a. Remove the adjusting lever spring.
b. Remove the E-ring.
c. Remove the automatic adjusting lever.
d. Remove the C-washer.
e. Remove the parking brake lever.





8. REMOVE WHEEL CYLINDER
a. Using SST, disconnect the brake line. Use a container to catch the brake fluid.
SST 09751-36011
b. Remove the 2 bolts and the wheel cylinder.
9. DISASSEMBLE WHEEL CYLINDER
a. Remove the 2 boots.
b. Remove the 2 pistons and spring.
c. Remove the 2 piston cups.


INSPECTION





1. INSPECT DISASSEMBLED PARTS
Inspect the disassembled parts for wear, rust or damage.
2. MEASURE BRAKE SHOE LINING THICKNESS
Using a ruler, measure the shoe lining thickness.
Standard thickness: 5.0 mm (0.197 inch)
Minimum thickness: 1.0 mm (0.039 inch)
If the thickness is less than the minimum, or shows signs of uneven wear, replace the brake shoes.

HINT: If any of the brake shoes have to be replaced, replace all of the rear brake shoes in order to maintain even braking.





3. MEASURE BRAKE DRUM INSIDE DIAMETER
Using brake drum gauge or equivalent, measure the inside diameter of the drum.
Standard inside diameter: 228.6 mm (9.000 inch)
Maximum inside diameter: 230.6 mm (9.079 inch)
If the drum is scored or worn, the brake drum may be lathed to the maximum inside diameter.





4. INSPECT BRAKE LINING AND DRUM FOR PROPER CONTACT
If the contact between the brake lining and drum is improper, repair the lining with a brake shoe grinder, or replace the brake shoe assembly.

INSTALLATION





NOTICE: Apply lithium soap base glycol grease and high temperature grease to the parts indicated by the arrows.

1. REASSEMBLE WHEEL CYLINDER
a. Install the 2 piston cups to the each pistons.
b. Install the 2 pistons and spring.
c. Install the 2 boots.





2. INSTALL WHEEL CYLINDER
a. Install the wheel cylinder and the 2 bolts
Torque: 10 Nm (100 Nm, 7 ft. lbs.)
b. Using SST, connect the brake line.
SST 09751-36011
Torque: 15 Nm (155 Nm, 11 ft. lbs.)
3. INSTALL PARKING BRAKE LEVER AND AUTOMATIC ADJUSTING LEVER
a. Install the parking brake lever to the rear shoe.
b. Install a new C-washer.
c. Install the automatic adjusting lever and the E-ring.
d. Install the adjusting lever spring.
4. INSTALL ADJUSTER TO REAR SHOE
Install the adjuster with the return spring to the rear shoe.





5. INSTALL REAR SHOE
a. Using needle-nose pliers, connect the parking brake cable to the lever and install the rear shoe with adjuster.
b. Using a screwdriver, connect the paring brake to the anchor plate.
c. Using SST, install the shoe hold-down spring, 2 cups and pin.
SST 09718-00010
6. INSTALL FRONT SHOE
a. Install the anchor spring to the rear shoe.
b. Connect the anchor spring to the front shoe and install the front shoe.





c. Using SST, install the shoe hold-down spring, 2 cups and pin.
SST 09718-00010





d. Using SST, connect the return spring to the front shoe.
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7. INSTALL BRAKE DRUM
8. FILL BRAKE RESERVOIR WITH BRAKE FLUID, BLEED BRAKE SYSTEM
9. CHECK FOR LEAKS
10. CHECK OPERATION OF AUTOMATIC ADJUSTING MECHANISM





a. Move the parking brake lever of the rear shoe back and forth. Check that the adjuster turns. If the adjuster does not turn, check for incorrect installation of the rear brake.
b. Adjust the adjuster length as short as possible.





c. Align the adjusting hole on the brake drum and the largest hole on the axle carrier, install the brake drum.
d. Pull the parking brake lever all the way up until a clicking sound can no longer be heard.





11. CHECK CLEARANCE BETWEEN BRAKE SHOES AND DRUM
a. Remove the drum.
b. Measure the brake drum inside diameter and diameter between the brake shoes. Check that the difference between the diameters is the correct shoe clearance.
Shoe clearance: 0.6 mm (0.024 inch)
If incorrect, check the parking brake system.