Caliper Piston, FN3

Caliper Piston, FN3

Special tools, testers and auxiliary items required

• Torque wrench (V.A.G 1331)

• Torque wrench (V.A.G 1332)

• Piston resetting tool (T10145)

• Trim removal wedge (3409)

• Assembly tool for protective caps (T10146/5)

• Lithium grease (G 052 150 A2)

Removing

- Use compressed air to force the piston out of the brake caliper housing.





• Place a piece of wood in the recess to prevent damage to the piston.

- Remove the seal.





- Use trim removal wedge (3409) for this.

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

Installing

- The surface of the piston and seal should be cleaned using methylated spirits and then dried.

- Apply a thin coat of lithium grease (G 052 150 A2) to the piston and seal before inserting.

- Insert the inner seal in the brake caliper housing groove using trim removal wedge (3409).





- Press in the protective cap with special tool - 1 - and - 2 -.





- Item - 1 -Assembly tool for protective caps (T10146/1)

- Item- 2 -Piston resetting tool ( T10145)

• Use jaw protectors

- Push the protective seal onto the brake caliper housing so that it lies against the housing all round.





- It should not be possible to remove the protective seal from the brake caliper housing by hand.

- Apply a thin coat of lithium grease (G 052 150 A2) to the piston and seal before inserting.

- Lift up the piston with an extension - 1 - and ratchet - 2 - as shown in the illustration and press lightly onto the protective cap.





• Make sure not to tilt the piston to avoid damage to the seal.

- Inflate the protective cap with compressed air (maximum 3 bar). The protective cap will then locate around the brake piston.

Use jaw protectors

- Press the piston into the brake caliper housing by hand.

• The protective seal inner sealing lip will then locate in the piston groove.