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

Special tools required: 

• 32 1 270

See STEERING AND WHEEL ALIGNMENT - SPECIAL TOOLS .

Necessary preliminary tasks: 

• Remove expansion tank   .
• Remove footwell trim 51 45 185 REMOVING AND INSTALLING/REPLACING PANEL FOR PEDALS (CONVERTIBLE) or 51 45 185 REMOVING AND INSTALLING/REPLACING PANEL FOR PEDALS (COUPE) .
• Read and comply with GENERAL INFORMATION .

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

Slacken nuts (2).

Installation: 

Replace self-locking nuts.

Tightening torque 35 11 1AZ, see 35 11 PEDAL ASSEMBLY CONSOLE

Fig 1: Identifying Locking Clip And Nuts

Courtesy of BMW OF NORTH AMERICA, INC.

Unfasten brake lines (1).

Installation: 

Tightening torque 34 32 1AZ, see 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.

Fig 2: Removing Brake Lines From Hydraulic Unit

Courtesy of BMW OF NORTH AMERICA, INC.

Installation: 

Tightening torque 34 32 1AZ, see 34 32 BRAKE LINES

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

Installation: 

Replace self-locking nuts.

Tightening torque 34 31 1AZ, see 34 31 BRAKE MASTER CYLINDER

Installation: 

Replace sealing ring.

Fig 3: Identifying 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: Inserting Brake Master Cylinder Into Brake Booster

Courtesy of BMW OF NORTH AMERICA, INC.

After installation: 

• Bleeding brake system with DSC