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

WARNING: This page does not describe the selected car, but rather 21 other vehicles, including the 2013 BMW 328xi, 2013 BMW 328i, 2012 BMW 328xi, 2012 BMW 328i, and 2011 BMW 328xi. However, it is still accessible from the selected car via links, so may be relevant.

Necessary preliminary tasks:

Remove expansion tank.
Remove footwell trim.
Read and comply with General Information.

After completing work:

Bleeding brake system with DSC

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

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

Slacken nuts (2).

Installation:

Replace self-locking nuts.

For tightening torque refer to 35 11 1AZ in 35 11 PEDAL ASSEMBLY CONSOLE .

Fig 1: Locking Clip And Slacken Nuts

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Do not bend brake lines.

Unfasten brake lines (1).

Installation:

For tightening torque refer to 34 32 1AZ in 34 32 BRAKE LINES .

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

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

Installation:

For tightening torque refer to 34 32 1AZ in 34 32 BRAKE LINES .

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

Fig 2: Brake Lines, Nuts, Line And Removal Direction

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

Replace self-locking nuts.

For tightening torque refer to 34 31 1AZ in 34 31 BRAKE MASTER CYLINDER .

Installation:

Replace sealing ring.

Fig 3: Sealing Ring

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

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: Brake Master Cylinder And Brake Booster

Courtesy of BMW OF NORTH AMERICA, INC.