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 the thickness is less than 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 screwdriver through the hole in the backing plate, and hold the automatic adjusting lever away from the adjuster.
b. Using another screwdriver, reduce the brake shoe adjuster by turning the adjusting wheel.

4. REMOVE FRONT SHOE





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





b. Using SST, remove the shoe hold-down spring, cups and pin.
SST 09718-00010
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, cups and pin.
SST 09718-00010
b. Using pliers, remove the adjusting lever spring.
c. Remove the adjuster.
d. Using pliers, disconnect the parking brake cable from the parking brake lever and remove the rear shoe.
6. REMOVE AUTOMATIC ADJUSTING LEVER AND PARKING BRAKE SHOE LEVER
a. Remove the C-washer.
b. Remove the automatic adjusting lever.
c. Remove the C-washer and shim.
d. Remove the parking brake shoe lever.





7. REMOVE WHEEL CYLINDER
a. Using SST, disconnect the brake line. Use a container to catch the brake fluid.
SST 09751-36011
Torque: 15 Nm (155 kgf-cm, 11 ft. lbs.)
b. Remove the 2 bolts and the wheel cylinder.
Torque: 10 Nm (100 kgf-cm, 7 ft. lbs.)
8. DISASSEMBLE WHEEL CYLINDER
a. Remove the 2 boots from the wheel cylinder.
b. Remove the 2 pistons from the wheel cylinder.
c. Remove the spring from the wheel cylinder.
d. Remove the 2 piston cups from the pistons.

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: 4.0 mm (0.157 inch)
Minimum thickness: 1.0 mm (0.039 inch)
If the thickness is less than the minimum or the shoe lining shows signs of uneven wear, replace the brake shoes.

HINT: If a brake shoe needs replacing, the brake shoes must be replaced as a set.





3. MEASURE BRAKE DRUM INSIDE DIAMETER
Using brake drum gauge or equivalent, measure the inside diameter of the drum.
Standard inside diameter: 200.0 mm (7.874 inch)
Maximum inside diameter: 201.0 mm (7.913 inch)
If the drum is scored or worn, the brake drum may be lathed to the maximum inside diameter.





4. INSPECT REAR 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.





5. MEASURE CLEARANCE BETWEEN BRAKE SHOE AND LEVER
Using a feeler gauge, measure the clearance.
Standard clearance: Less than 0.35 mm (0.0138 inch)

Brake Shoe To Lever Shim Specification.:

If the clearance is not within the specification, replace the shim with one of the correct size.





6. IF NECESSARY, REPLACE SHIM
a. Using a screw driver, remove the C-washer and shim.
b. Install the correct size shim and a new C-washer.
c. Remeasure the clearance.

INSTALLATION
Installation is in the reverse order of removal.

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

1. 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 to the as short as possible.





c. Install the brake drum.
d. Pull the parking brake lever all the way up until a clicking sound can no longer be heard.





2. CHECK CLEARANCE BETWEEN BRAKE SHOES AND DRUM
a. Remove the brake drum.
b. Measure the brake drum inside diameter and diameter of 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.
3. FILL BRAKE RESERVOIR WITH BRAKE FLUID
4. BLEED BRAKE SYSTEM
5. CHECK FOR LEAKS