34 31 181 Removing and installing / replacing expansion tank for hydraulic brake actuation

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:

Read and comply with General Information.
Remove lower section of microfilter housing

NOTE: Suck the brake fluid out of the expansion tank. Use a suction bottle used exclusively for drawing off brake fluid.

Do not reuse drawn out brake fluid.

After completing work:

Bleed braking system

Pull off supply hose (1) of clutch hydraulic system if necessary.

Unfasten plug connection (2) and disconnect.

Unlock quick-release fastener (3) and disconnect vacuum line.

Feed brake line out of rubber grommet and remove cover (4).

Fig 1: Plug Connection, Cover, Supply Hose And Quick-Release Fastener

G04726649

Courtesy of BMW OF NORTH AMERICA, INC.

Unclip locking pin (1) from retaining lugs (2) and pull out locking pin.

Pull expansion tank in direction of arrow vertically out of brake master cylinder.

Fig 2: Locking Pin, Retaining Lugs And Removal Direction

G04726650

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Check rubber plug in brake master cylinder for damage and replace if necessary.

Push the expansion tank vertically onto the master brake cylinder.

Fig 3: Expansion Tank, Brake Master Cylinder And Installation Direction

G04726651

Courtesy of BMW OF NORTH AMERICA, INC.