34 11 552 Overhauling left or right front brake caliper (brake caliper removed)

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2019 MINI Cooper, 2018 MINI Cooper, 2017 MINI Cooper, 2016 MINI Cooper, and 2015 MINI Cooper. However, it is still accessible from the selected car via links, so may be relevant.

Necessary preliminary tasks:

Remove the FRONT BRAKE CALIPER .

WARNING: In the following operation, large forces occur at the brake caliper piston.
Danger of injury!

Carefully force piston out through connecting bore with compressed air.

To protect the piston, place a protective plate (e.g. hardwood or rubber plate) in the caliper recess.

Fig 1: Removing Piston Using Compressed Air

Courtesy of BMW OF NORTH AMERICA, INC.

Do not grip piston with fingers - pinch hazard !

Press off dust boot (1).

Fig 2: Pressing Dust Boot

Courtesy of BMW OF NORTH AMERICA, INC.

Carefully remove sealing ring (1).

Clean cylinder bores and parts and dry with compressed air.

Thoroughly inspect cylinder bore, piston and flange surfaces for damage.

Material removing rework on cylinders and pistons is not permitted.

Fig 3: Identifying Sealing Ring

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

Insert sealing ring (1).

Apply a light coat of ATE brake cylinder paste to cylinder bore, piston and sealing ring,

Fig 4: Identifying Sealing Ring

Courtesy of BMW OF NORTH AMERICA, INC.

Fit dust boot (1) in annular groove of piston (2).

IMPORTANT: Do not twist brake piston.

Press piston into cylinder bore.

Evenly press dust boot (1) onto brake caliper housing up to limit position.

NOTE: The area between the dust boot and the brake caliper housing must be kept dry. It must not come into contact with Ate brake cylinder paste or brake fluid so as to ensure that the dust boot is perfectly fitted.

Fig 5: Fitting Dust Boot In Annular Groove Of Piston

Courtesy of BMW OF NORTH AMERICA, INC.