- Raise and support the axle.
- Remove the wheel and tire.
- Back off the brake adjustment if necessary and remove the drum.
- Disconnect and plug the brake line.
- Remove the brake shoe pull-back springs.
- Remove the screws securing the wheel cylinder to the backing plate.
- Disengage the wheel cylinder pushrods from the brake shoes and remove the wheel cylinder.
As with master cylinders, overhaul kits for wheel cylinders are readily available. When rebuilding and installing wheel cylinders, avoid getting any contaminants into the system. Always install clean, new high-quality brake fluid. If dirty or improper fluid has been used, it will be necessary to drain the entire system, flush the system with proper brake fluid, replace all rubber components, refill, and bleed the system.
- Remove the rubber boots from the cylinder ends with pliers. Discard the boots.
- Remove and discard the pistons and cups.
- Wash the cylinder and metal parts in denatured alcohol or clean brake fluid.
- Allow the parts to air dry or use compressed air. Do not use rags for cleaning since lint will remain in the cylinder bore.
- Inspect the piston and replace it if it shows scratches.
- Lubricate the cylinder bore and counterbore with clean brake fluid.
- Install the rubber cups (flat side out) and then the pistons (flat side in).
- Insert new boots into the counterbores by hand. Do not lubricate the boots.
- Installation is the reverse of removal. Adjust the brakes and bleed the system.