If replacement is indicated, usually because of fluid leakage or sticky operation, it is recommended that the wheel cylinders be replaced, not overhauled. Always replace the wheel cylinders in pairs - never replace just one of them. To remove, first remove the brake drum and brake shoes. Then, remove the
Brake Line fitting from the rear of the wheel cylinder with a flare-nut wrench. Don't pull the metal line out of the wheel cylinder - it could bend, making installation difficult. Next, remove the two nuts securing the wheel cylinder to the brake backing plate. After that, remove the wheel cylinder and plug the end of the brake line to prevent the loss of brake fluid and the entry of dirt. For installation, place the wheel cylinder in position and, while it's still loose, connect the brake line to it, being careful not to cross-thread the fitting. Don't tighten the fitting yet. Install the bolts and tighten them. Tighten the line fitting securely. Finally, bleed the brakes. Don't drive the vehicle in traffic until the operation of the brakes has been thoroughly tested.