34 31 505 Removing and Installing/Replacing Master Brake Cylinder for DSC

Special tools required: 

• 32 1 270 

Necessary preliminary tasks: 

• Remove expansion tank  . See 34 31 181 REMOVING AND INSTALLING/REPLACING EXPANSION TANK FOR HYDRAULIC BRAKE ACTUATION 
• Remove footwell trim  . See 51 45 185 REMOVING AND INSTALLING/REPLACING PANEL FOR PEDALS
• Read and comply with General Information  . See 34 00 ... GENERAL INFORMATION )

After completing tasks, bleed brake system with DSC  . See 34 00 050 BLEEDING BRAKE SYSTEM WITH DSC 

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 & Nuts

Courtesy of BMW OF NORTH AMERICA, INC.

Unfasten brake lines (1).

Detach brake lines at junction (2) and remove short sections.

Seal off brake lines and brake master cylinder with plugs 32 1 270  . See 32 1 270 PLUGS (SET)

Installation: 

Fit lines at both connection points and then tighten down.

Tightening torque 34 32 1AZ  . See 34 32 BRAKE LINES

Release nuts (3) and feed brake master cylinder out of brake booster.

Fig 2: Identifying Brake Line, Brake Lines Junction & Nuts

Courtesy of BMW OF NORTH AMERICA, INC.

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: Identifying Brake Booster & Brake Master Cylinder

Courtesy of BMW OF NORTH AMERICA, INC.