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

WARNING: This page does not describe the selected car, but rather 18 other vehicles, including the 2015 BMW Alpina B7L xDrive, 2015 BMW Alpina B7 xDrive, 2015 BMW 750i xDrive, 2015 BMW 750Li xDrive, and 2015 BMW 740Li xDrive. 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 COVER FOR COWL PANEL on left.

NOTE: Extract brake fluid out of expansion tank. Use a suction bottle used exclusively for drawing off brake fluid. Do not reuse drawn out brake fluid.

Disconnect plug connection (1).

Pull out locking pin (2) and lift out expansion tank in vertical direction.

Fig 1: Identifying Plug Connection And Locking Pin

Courtesy of BMW OF NORTH AMERICA, INC.

IMPORTANT: Check rubber plugs (1) in brake master cylinder for damage and replace if necessary.
Push the expansion tank vertically onto the master brake cylinder.

Fig 2: Identifying Brake Master Cylinder Rubber Plugs

Courtesy of BMW OF NORTH AMERICA, INC.