34 31 181 Removing And Installing / Replacing Expansion Tank For Hydraulic Brake Actuation

WARNING: This page is about a different car, the 2008 BMW Alpina and 2007 BMW Alpina. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Read and comply with General Information . See 34 00 ... GENERAL INFORMATION .

Observe safety instructions on raising the vehicle. See 00 ... ... LIFTING VEHICLE WITH A LIFTING PLATFORM .

Remove microfilter (1).

Fig 1: Identifying Microfilter

Courtesy of BMW OF NORTH AMERICA, INC.

Suck the brake fluid out of the expansion tank.

IMPORTANT: Do not reuse drawn out brake fluid.
Use suction bottle exclusively to draw off brake fluid.

Fig 2: Sucking Brake Fluid Out Of Expansion Tank

Courtesy of BMW OF NORTH AMERICA, INC.

Disconnect plug connection (1).

Release hose clip (2) and detach supply hose (3) of precharging pump from expansion tank.

IMPORTANT: Supply hose must be secured in vertical position so that no fluid emerges.

Press retaining tabs (4) on left and right outwards and pull off expansion tank (5) vertically upwards.

Fig 3: Identifying Plug Connection, Hose Clip, Supply Hose, Retaining Tabs And Expansion Tank

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 4: Pushing Expansion Tank Vertically Onto Master Brake Cylinder

Courtesy of BMW OF NORTH AMERICA, INC.