REMOVAL & INSTALLATION
See Figures 1 through 13
- Raise and support the vehicle and remove the wheel and brake drum from the wheel to be worked on.
If you have never replaced the brakes on a vehicle before and you are not too familiar with the procedures involved, only dissemble and assemble one side at a time, leaving the other side intact as a reference during reassembly.
- Install a clamp over the ends of the wheel cylinder to prevent the pistons of the wheel cylinder from coming out, causing loss of fluid and much grief.
- Contract the brake shoes by pulling the self-adjusting lever away from the starwheel adjustment screw and turn the starwheel up and back until the pivot nut is drawn onto the starwheel as far as it will come.
- Pull the adjusting lever, cable and automatic adjuster spring down and toward the rear to unhook the pivot hook from the large hole in the secondary shoe web. Do not attempt to pry the pivot hook from the hole.
- Remove the automatic adjuster spring and the adjusting lever.
- Remove the secondary shoe-to-anchor spring with a brake tool. (Brake tools are very common implements and are available to auto parts stores). Remove the primary shoe-to-anchor spring and unhook the cable anchor. Remove the anchor pin plate.
- Remove the cable guide from the secondary shoe.
- Remove the shoe holddown springs, shoes, adjusting screw, pivot nut, and socket. Note the color of each holddown spring for assembly. To remove the holddown springs, reach behind the brake backing plate and place one finger on the end of one of the brake holddown spring mounting pins. Using a pair of pliers, grasp the washer type retainer on top of the holddown spring that corresponds to the pin which you are holding. Push down on the pliers and turn them 90 degrees to align the slot in the washer with the head on the spring mounting pin. Remove the spring and washer retainer and repeat this operation on the hold down spring on the other shoe.
- Remove the parking brake link and spring. Disconnect the parking brake cable from the parking brake lever.
- After removing the rear brake secondary shoe, disassemble the parking brake lever from the shoe by removing the retaining clip and spring washer.
- Assemble the parking brake lever to the secondary shoe and secure it with the spring washer and retaining clip.
- Apply a light coating of Lubriplate® at the points where the brake shoes contact the backing plate.
- Position the brake shoes on the backing plate, and install the holddown spring pins, springs, and spring washer type retainers. On the rear brake, install the parking brake link, spring and washer. Connect the parking brake cable to the parking brake lever.
- Install the anchor pin plate, and place the cable anchor over the anchor pin with the crimped side toward the backing plate.
- Install the primary shoe-to-anchor spring with the brake tool.
- Install the cable guide on the secondary shoe web with the flanged holes fitted into the hole in the secondary shoe web. Thread the cable around the cable guide groove.
- Install the secondary shoe-to-anchor (long) spring. Be sure that the cable end is not cocked or binding on the anchor pin when installed. All of the parts should be flat on the anchor pin. Remove the wheel cylinder piston clamp.
- Apply Lubriplate® to the threads and the socket end of the adjusting starwheel screw. Turn the adjusting screw into the adjusting pivot nut to the limit of the threads and then back off 1 / 2 turn.
Interchanging the brake shoe adjusting screw assemblies from one side of the vehicle to the other would cause the brake shoes to retract rather than expand each time the automatic adjusting mechanism is operated. To prevent this, the socket end of the adjusting screw is stamped with an "R" or an "L" for "RIGHT" or "LEFT". The adjusting pivot nuts can be distinguished by the number of lines machined around the body of the nut; one line indicates left hand nut and two lines indicate a right hand nut.
- Place the adjusting socket on the screw and install this assembly between the shoe ends with the adjusting screw nearest to the secondary shoe.
- Place the cable hook into the hole in the adjusting lever from the backing plate side. The adjusting levers are stamped with an R (right) or a L (left) to indicate their installation on the right or left hand brake assembly.
- Position the hooked end of the adjuster spring in the primary shoe web and connect the loop end of the spring to the adjuster lever hole.
- Pull the adjuster lever, cable and automatic adjuster spring down toward the rear to engage the pivot hook in the large hole in the secondary shoe web.
- After installation, check the action of the adjuster by pulling the section of the cable guide and the adjusting lever toward the secondary shoe web far enough to lift the lever past a tooth on the adjusting screw starwheel. The lever should snap into position behind the next tooth, and release of the cable should cause the adjuster spring to return the lever to its original position. This return action of the lever will turn the adjusting screw starwheel one tooth. The lever should contact the adjusting screw starwheel one tooth above the centerline of the adjusting screw.
If the automatic adjusting mechanism does not perform properly, check the following:
- Check the cable and fittings. The cable ends should fill or extend slightly beyond the crimped section of the fittings. If this is not the case, replace the cable.
- Check the cable guide for damage. The cable groove should be parallel to the shoe web, and the body of the guide should lie flat against the web. Replace the cable guide if this is not so.
- Check the pivot hook on the lever. The hook surfaces should be square with the body on the lever for proper pivoting. Repair or replace the hook as necessary.
- Make sure that the adjusting screw starwheel is properly seated in the notch in the shoe web.
See Figures 14, 15 and 16
- Raise and support the vehicle.
- Remove the wheel and drum.
- Remove the parking brake lever assembly retaining nut from behind the backing plate and remove the parking brake lever assembly.
- Remove the adjusting cable assembly from the anchor pin, cable guide, and adjusting lever.
- Remove the brake shoe retracting springs.
- Remove the brake shoe holddown spring from each shoe.
- Remove the brake shoes and adjusting screw assembly.
- Disassembly the adjusting screw assembly.
- Clean the ledge pads on the backing plate. Apply a light coat of Lubriplate® to the ledge pads (where the brake shoes rub the backing plate).
- Apply Lubriplate® to the adjusting screw assembly and the holddown and retracting spring contacts on the brake shoes.
- Install the upper retracting spring on the primary and secondary shoes and position the shoe assembly on the backing plate with the wheel cylinder pushrods in the shoe slots.
- Install the brake shoe holddown springs.
- Install the brake shoe adjustment screw assembly with the slot in the head of the adjusting screw toward the primary shoe, lower retracting spring, adjusting lever spring, adjusting lever assembly, and connect the adjusting cable to the adjusting lever. Position the cable in the cable guide and install the cable anchor fitting on the anchor pin.
- Install the adjusting screw assemblies in the same locations from which they were removed. Interchanging the brake shoe adjusting screws from one side of the vehicle to the other will cause the brake shoes to retract rather than expand each time the automatic adjusting mechanism is operated. To prevent incorrect installation, the socket end of each adjusting screw is stamped with an R or an L to indicate their installation on the right or left side of the vehicle. The adjusting pivot nuts can be distinguished by the number of lines machined around the body of the nut. Two lines indicate a right hand nut; one line indicates a left hand nut.
- Install the parking brake assembly in the anchor pin and secure with the retaining nut behind the backing plate.
- Adjust the brakes before installing the brake drums and wheels. Install the brake drums and wheels.
- Lower the vehicle and road test the brakes. New brakes may pull to one side or the other before they are seated. Continued pulling or erratic braking should not occur.