34 33 505 Removing and installing or replacing brake booster

Necessary preliminary tasks: 

• Read and comply with GENERAL INFORMATION .
• Remove BRAKE MASTER CYLINDER 
• Disconnect BATTERY NEGATIVE LEAD
• Remove TRIM PANEL for pedal assembly

Release brake lines (1) and remove.

Installation: 

Tightening torque 34 32 1AZ .

Remove non-return valve (2) in direction of arrow from brake booster.

Installation: 

Check rubber seal in brake booster and replace if necessary.

Fig 1: Removing Non-Return Valve From Brake Booster

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Disconnect plug connection (1).

Release screw (2) and swing out battery terminal.

Fig 2: Removing Battery Terminal Plug Connection And Screw

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Disconnect plug connection (1).

Unhinge the recoil spring (2).

Remove retaining clip (3).

Installation: 

Replace locking clip (3).

Locking clip (3) must be seated with both legs in the pin groove.

Unscrew nuts (4).

Installation: 

Tightening torque 35 11 1AZ .

Fig 3: Identifying Plug Connection, Recoil Spring, Locking Clip And Nuts

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Move brake booster a little towards engine compartment.

Feed piston rod (1) by turning bearing support out of retaining lug (2).

Installation: 

Feed brake pedal in depressed position into piston rod, moving the brake booster a little towards the engine compartment.

Remove bearing support.

Fig 4: Removing Piston Rod Out Of Retaining Lug

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Carefully pull brake booster (1) out of bulkhead and tilt out.

Fig 5: Identifying Brake Booster

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