REAR WHEEL CYLINDERS
Replacement

1. Remove the brake shoes from the backplate as detailed above.
2. Unscrew the brake pipe union from the rear of the wheel cylinder and pull the pipe outwards slightly so that it clears the cylinder spigot. Plug the pipe end to prevent loss of brake fluid. Ideally the system should be sealed off by clamping the flexible brake hose with a proper brake hose clamp.
3. Unscrew the bleed valve from the wheel cylinder. Extract the retaining circlip from the cylinder spigot protruding through the backplate and withdraw the wheel cylinder together with it gasket.
4. Install the new wheel cylinder in the reverse order of removing. It will facilitate reconnecting the brake pipe, if threads are started into the cylinder connection before the cylinder circlip is fitted.
Use a new circlip to secure the wheel cylinder, and position the circlip as shown in the illustration.
5. Refit the brake shoes, then bleed the braking system as detailed later in this section.

Seal Renewal

As with the front brakes, the cylinder piston seals can be replaced without removing the wheel cylinder from the backplate, but again great care must be taken to ensure that all dirt, etc., is cleaned away from the exterior of the cylinder before dismantling.
With the brake shoes removed, remove the rubber dust covers from the ends of the cylinder and withdraw the piston assemblies . Remove the rubber seal from each piston.
Clean and inspect the components as described in 'HYDRAULIC SYSTEM OVERHAUL' previously.
If the pistons and cylinder bore are in good condition, lubricate the pistons with clean brake fluid and fit a new seal to each piston. The flat face of the seat must face towards the slotted outer end of the piston. Fit a new rubber dust cover at the slotted end of the pistons. Lubricate the cylinder bore with brake fluid and insert the pistons, seal end first, into the bore. Take care to avoid damaging the seal lips as they are installed. Fit the dust covers to the ends of the cylinders, ensuring that they engage correctly in their respective grooves.
Refit the brake shoes, then bleed the braking system as detailed under the appropriate heading later in this section.