Front brake caliper piston, removing and installing

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Fig 1: Identifying Special Tools - Front Brake Caliper Piston, Removing And Installing

Courtesy of VOLKSWAGEN UNITED STATES, INC.

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

Fig 2: Using Compressed Air To Force Piston Out Of Brake Caliper Housing

Courtesy of VOLKSWAGEN UNITED STATES, INC.

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

NOTE:

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

Fig 3: Removing Seal With Trim Removal Wedge 3409

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Remove seal.
Use trim removal wedge 3409 for this.

NOTE:

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 piston and seal before inserting.

Fig 4: Installing Sealing Ring In Brake Caliper

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Insert inner seal in brake caliper housing groove using trim removal wedge 3409.

Fig 5: Pressing Protective Cap With Assembly Tool And Piston Resetting Tool Into Brake Caliper

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Press in protective cap with special tool - 1 - and - 2 -.
Item - 1 - Assembly tool for protective caps T10146/1
Item - 2 - Piston resetting tool T10145

NOTE:

Use jaw protectors

Fig 6: Pushing Protective Seal Onto Brake Caliper Housing So That It Lies Against Housing All Round

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Push protective seal onto 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 piston and seal before inserting.

Fig 7: Lifting Up Piston With Standard Extension And Ratchet Attachment

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Lift up piston with standard extension and ratchet attachment as shown in illustration and press lightly onto protective cap.

NOTE:

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

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

Use jaw protectors

Press piston into brake caliper housing by hand.

NOTE:

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