34 11 552 Overhauling left or right front brake caliper (brake caliper removed) (2' Series coupe and convertible, 2017-2021)

Necessary preliminary tasks: 

• Refer to REMOVING THE FRONT BRAKE CALIPER .

Carefully force piston out through connecting bore with compressed air.

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

Do not grip piston with fingers - pinch hazard! 

Press off dust boot (1).

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Carefully remove sealing ring (1).

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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.

Installation: 

Insert sealing ring (1).

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Apply a light coat of ATE BRAKE CYLINDER PASTE to cylinder bore, piston and sealing ring,

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

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Attention! 

Do not twist brake piston.

Press piston into cylinder bore.

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

Required follow-up work: 

• Refer to INSTALLING FRONT BRAKE CALIPER .