34 31 505 Removing and installing/replacing master brake cylinder for DSC

Special tools required:

32 1 270

Necessary preliminary work:

Remove EXPANSION TANK .
Remove FOOTWELL TRIM .
Read and comply with GENERAL INFORMATION .

IMPORTANT: Before beginning work, fully press the brake pedal several times to reduce the vacuum pressure in the brake servo.

IMPORTANT: The brake servo must be slackened so that the brake master cylinder can be removed and installed without tilting!

Remove retaining clip (1) and disengage and pull out locking pin.

Slacken nuts (2).

Installation note:

Replace self-locking nuts.

Tightening torque 35 11 1AZ .

Fig 1: Identifying Brake Pedal Locking Clip And Nuts

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Do not bend brake lines.

Unfasten brake lines (1).

Installation note:

Tightening torque 34 32 1AZ .

Close off brake lines and brake master cylinder with seal plugs 32 1 270 .

If necessary, detach line (3) from hydraulic unit and press downwards slightly.

Installation note:

Tightening torque 34 32 1AZ .

Fig 2: Detaching Line From Hydraulic Unit

Courtesy of BMW OF NORTH AMERICA, INC.

Release nuts (2) and feed brake master cylinder out of brake booster.

Installation note:

Replace self-locking nuts.

Tightening torque 34 31 1AZ .

Installation note:

Replace sealing ring.

Fig 3: Identifying Sealing Ring

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note:

When inserting the brake master cylinder (2) into the brake booster (1), make sure the pressure rod of the brake booster and that of the brake master cylinder meet each other on one level.

Fig 4: Identifying Brake Master Cylinder And Booster

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After installation:

BLEEDING BRAKE SYSTEM WITH DSC .