Vacuum Brake Booster Check Valve: Service and Repair

34 33 051 Removing And Installing/Replacing Non-Return Valve For Brake Booster







Necessary preliminary tasks:
- Read and comply with General Information.
- Remove hydraulic unit

IMPORTANT:
- If a rubber vacuum hose is fitted, it can be replaced individually.
- If a plastic vacuum line is fitted, it can only be replaced as a single unit together with the non-return valve.







NOTE: Before beginning work, fully press the brake pedal several times to reduce the vacuum pressure in the brake servo. This makes it easier to remove the non-return valve.







Remove non-return valve (1) from brake servo.
Unlock quick-release coupling (2) and detach vacuum line.
If necessary, disconnect plug connection (3) and remove differential pressure sensor.
Feed out vacuum line.

Installation note:
Check sealing ring in brake servo and replace if necessary.