Front Brakes

Brake Caliper Piston

Removal and installation of pistons is identical on the various brake calipers.

Special tools, testers and auxiliary items required

• Trim removal wedge (3409)

• Piston resetting tool (T10145)

Removing

- Force pistons out individually of brake caliper housing using compressed air.





Only one piston can be pressed out at a time. When doing this, hold the opposing piston in the caliper housing using the piston resetting tool - a -. Block the other pistons, e.g. using wood blocks - b -. In addition, place a wooden board - c - in front of the piston resetting tool so that the piston will not be damaged when pressed out.

- Remove seal with trim removal wedge (3409).





When removing, make sure that surface of piston bore is not damaged.

Installing

- The surface of the piston and seal must only be cleaned with mineral spirits and then dried.

- Thinly coat piston and seal with assembly paste (G 052 150 A2) before inserting.

- Insert oil seal into the piston bore.





- Install protective cap on piston.





- Using equal pressure, push piston into the bore.





The protective cap must be seated properly in the groove, push slightly farther if necessary.