Disassembling and Assembling

Rear brake caliper, servicing





Notes:
^ Install all parts supplied in repair kit.
^ Only use appropriate solvents for cleaning to clean brake parts.
^ New brake calipers are filled with brake fluid and prebled.
^ Apply a thin coat of paste G 052 150 A2 to brake cylinders, pistons and seals.
^ When carrying out repairs it is essential to pre-bleed the brake calipers (without brake pads) before installing in the vehicle Page 4733
1 - Selflocking bolts, 35 Nm
^ Always replace
^ When loosening and tightening counterhold on guide pin
2 - Brake caliper housing with parking brake cable lever
^ Replace if leaking at the parking brake cable lever
^ Prebleed caliper housing after repairing Page 47-33
3 - Bleed valve
^ Apply a thin coat of assembly paste G 052 150 A2 to threads before screwing in
4 - Dust cap
5 - Sealing ring
6 - Piston with - automatic adjustment
^ Apply a thin coat of paste G 052 150A2 to piston before installing
7 - Protective seal
^ Pull outer sealing lip onto piston
8 - Guide pins
^ Grease before pulling on protective cap
9 - Protective cap
^ Pull onto brake carrier and guide pin
10 - Brake carrier with guide pin and protective cap
^ Supplied as assembled replacement part, with sufficient grease on guise pins
^ If protective caps or guide pins are damaged, install repair kit. Use grease packet supplied to lubricate the guide pins.

Rear brake caliper piston, removing and installing
Special tools and workshop equipment required





^ 3272 Reset and screwout tool
^ 3272/1 Reset and screwout tool plate





^ 3409 Wedge
^ Bleeder bottle

Removing





^ Screw piston out of brake caliper housing by turning the knurled wheel counter clockwise.

Notes:
^ Install special tool 3272 so that the collar (arrow) is before the piston.
^ For pistons that are difficult to move, use open-end wrench (use 13 mm) on the flats (arrow A) provided for this purpose.





^ Remove seal using wedge 3409.

Note: When removing make sure that the surface of the cylinder is not damaged.

Installing
^ Clean surfaces of the piston and seal (use only appropriate solvent) then dry.
^ Apply a thin coat of paste G 052 150 A2 to piston and seal before installing.
^ Install oil seal in brake caliper housing.





^ Place protective seal with the outer sealing lip on the piston.





^ Using 3409 wedge, insert the inner sealing lip into the cylinder grove.

Note: Hold piston in front of caliper housing.





^ Screw piston into housing by turning knurled wheel clockwise.

Notes:
^ Install special tool 3272 so that the collar of the tool rests on special tool 327211.
^ For pistons that are difficult to move, use open-end wrench (use 13 mm) on flats (arrow A).

^ Install brake pads.

Pre-bleeding brake caliper





^ Open bleed valve -arrow A- and fill with brake fluid, using a standard bleeder bottle until bubble-free brake fluid flows from the threaded hole -arrow B- (brake hose connection). Close bleed valve.

Note: Position brake caliper as illustrated to pre-bleed.