Master Cylinder: Removal

WARNING: This page does not describe the selected car, but rather 92 other vehicles, including the 2002 BMW Z3, 2002 BMW M Roadster, 2002 BMW M Coupe, 2001 BMW Z3, and 2001 BMW M5. However, it is still accessible from the selected car via links, so may be relevant.

Suck the brake fluid out of expansion tank. Use a suction device used exclusively for drawing off brake fluid.
Remove brake fluid expansion tank. See BRAKE EXPANSION TANK .
On all models, disconnect all hydraulic lines from master cylinder. Close off the brake lines and the master brake cylinder using appropriate seal plugs. See Fig 1.
Remove master cylinder-to-power booster nuts. Remove support and master cylinder.
Replace O-ring. See Fig 2.

Fig 1: Locating Screw Connections

Courtesy of BMW OF NORTH AMERICA, INC.

Fig 2: Locating O-Ring

Courtesy of BMW OF NORTH AMERICA, INC.