1. Remove the brake shoes from the backplate as detailed previously.
2. Disconnect the bridging pipe from the appropriate wheel cylinder and plug the pipe end to prevent loss of fluid and the ingress of dirt. Ideally, the brake hose should be clamped with a proper brake pipe clamp to minimise fluid loss.
3. If removing the front wheel cylinder, slacken the brake hose at the wheel cylinder. If removing the rear cylinder, unscrew the bleed valve from the wheel cylinder.
4. Remove the two bolts securing the wheel cylinder to the backplate and detach the cylinder together with its gasket. In the case of the front wheel cylinder, pull the cylinder through the backplate and unscrew the cylinder from the brake hose. Plug the hose end to prevent loss of fluid.
5. Install the new wheel cylinder in the reverse order of removing. Screw the front cylinder onto the brake hose before securing the cylinder to the backplate.
6. Refit the brake shoes, then bleed the braking system as detailed later in this section.

Seal Renewal

The cylinder piston seals can be replaced without removing the wheel cylinder from the backplate, but great care must be taken to ensure that all dirt, etc., is cleaned away from the exterior of the cylinder and the surrounding area on the backplate before dismantling.
With the brake shoes removed as detailed previously, ease the rubber dust cover off the end of the cylinder and withdraw the piston assembly from the cylinder bore . Remove the dust cover and rubber seal from the piston.

Clean and inspect the components as described in 'HYDRAULIC SYSTEM OVERHAUL' at the beginning of this section.
If the piston and cylinder bore are in good condition, lubricate the piston with clean brake fluid and fit the new seal to the piston. The flat face on the seal must face towards the slotted outer end of the piston. Lubricate the cylinder bore with brake fluid and insert the piston, seal end first, into the bore. Take great care to avoid damaging the seal lip during this operation. Fit the new dust cover to the end of the cylinder and the piston.
Refit the brake shoes, then bleed the braking system as detailed later under the appropriate heading.