When checking cylinders for leaks, lift the outer edge of the boot and check the fluid. A little moisture, usually covered in brake dust, is normal. If there is any significant dampness or fluid leakage, replace the cylinder immediately.
Withdrawal
1. Raise and secure the vehicle.
2. Remove the wheel.
3. Remove the brake drum and shoes.
4. Disconnect the brake line from the wheel cylinder. Plug the pipeline.
5. Loosen the 2 lock nuts on the wheel cylinder on the inside of the support plate; take off wheel cylinder.
For installation:
6. Lightly coat the grooves on the wheel cylinder piston with grease.
7. Install the cylinder by tightening the nuts to 8 Nm.
8. Attach the pipeline of the brake system and tighten to 15 Nm.
9. Install the brake shoes and drum.
10. Bleed the brakes.
11. Install the wheel; lower the car to the ground.
Repair
Remove the wheel cylinder dust seals from the grooves so that the cylinder pistons can be removed.
Flush all parts in fresh brake fluid and check the cylinder bore and pistons for scratches and other damage, replacing as needed. Check the clearance between the piston and the cylinder bore by measuring the difference between the piston diameter and the cylinder bore diameter. This value is 0.020-0.100 mm. If the holes are corroded, the cylinder must be replaced. Do not bore or expand the cylinder.
Repair kits include the necessary seals; pistons and spring may be missing. When assembling the wheel cylinder, coat the pistons, piston caps and cylinder walls with a thin layer of brake fluid.