Rear Brake Calipers

Reconditioning Rear Brake Calipers

Special Tools: 981 4071, 999 5634

Preparations
Set the parking brake mechanism using the central adjuster nut in the parking brake handle.
Remove the wheel.
Clean the brake caliper thoroughly.

Draining the brake fluid







Remove the protective cap from the bleed nipple. Connect a hose. Unscrew the nipple.
Lock the pedal in its depressed position using a pedal jack.
Use a container to collect the brake fluid.

Removing the entire rear brake caliper

Remove:







- the brake hose from the brake caliper
- the screws from the brake caliper guides
- the brake caliper from the holder, and the brake pads
- the parking brake cable from the support. First pull the rubber sleeve up around the parking brake cable
- the parking brake cable spring (if installed)
- the inner mechanical cable from the parking brake handle
- the remaining brake fluid.

Remove the rear brake caliper

Remove:







- the piston and casing by rotating the piston and casing counterclockwise out through the brake caliper. Use tool 999 5634
- the O-ring
- use weatherstrip tool 981 4071 to prevent damage to the groove edges
- the bleed nipple.

Cleaning and checking rear brake calipers
Clean the components using denatured alcohol. Check for wear, damage, cracks and rust. Replace components if necessary.
Always replace the O-ring and dirt guard.
Ensure that the wiring and the groove for the O-ring are clean.
Completely replace the brake caliper if the cylinder displays signs of more severe damage or scratches.
Remove traces of rust using fine sandpaper.

Assemble the rear brake caliper
Clean the components using compressed air.
Lubricate the cylinder wall, piston and the new O-ring using brake fluid.

Install:







- The O-ring in the cylinder
- the dirt protector on the piston
- the dirt protector (and piston) in the groove in the cylinder.

Carefully press the piston into the cylinder. Slide the piston in as far as possible using a firm clockwise movement. Use special tool 999 5634.
Ensure that the dirt guard is correctly positioned.
Install the bleed nipple. Tighten the bleed nipple. Tighten to 5 Nm.

Finishing

Check
- the brake caliper guide.
- the brake disc.

Install the brake pads.
Install the parking brake cable.
Install the brake caliper on the holder. Install the screw. Tighten to 33 Nm. Install the brake hose. Use new seals. Tightening torque 29 Nm.
Ensure that the brake hose is not twisted.
Bleed the brake system.
Install the wheel. Depress the brake pedal a few times. Check the brake fluid level.
Check the parking brake setting.