Brake Master Cylinder and Brake Servo, Assembly

Brake booster/brake master cylinder





Exploded view

Note:
^ Brake master cylinder and brake booster can be replaced as individual components.
^ The Fig. shows the brake booster of the ABS/ESP Mk 20 system.
^ With the ABS/ESP Mk 60 system the components -item 2, 14 and 15- as well as the magnetic coil for brake pressure, in brake booster -N247- on the brake booster and the brake pressure release solenoid -F84- are missing.

1. Brake booster
2. Bracket
^ Used to mount the electrical connector -Item 14
3. Cap
^ With integrated float and brake fluid warning indicator
4. Brake fluid reservoir
^ Moisten with brake fluid and press into sealing plugs in brake master cylinder
^ Locate with retaining pin -Item 6 -
^ With warning contact for brake fluid level (phased introduction)
^ Remove brake fluid reservoir to replace warning contact
5. Sealing plug
^ Moisten with brake fluid and press into brake master cylinder
^ Press brake fluid reservoir into sealing plugs.
6. Retaining pin
^ For brake fluid reservoir
7. Brake master cylinder
8. Mounting plate
^ Different versions available
^ Application, Refer to Parts Supplier
9. Nut - 4 Nm
^ Self-locking
^ Replacing each time after removing
10. Heat shield
^ Application, Refer to Parts Supplier
11. Sensor -2- for brake pressure -G214
12. Sender 1 for brake booster -G201
13. Seal
14. Electrical connector
15. Electrical wire
16. Vacuum line
^ Check non-return valve, Refer to Fig. 2
17. Sealing plug
18. Gasket
19. Nut-28 Nm
^ Replacing each time after removing
20. Boot





Fig. 1 Checking inner boot of brake booster
^ Remove storage compartment on driver's side.
^ Check whether bellows have slipped out of annular groove as shown in this figure.
^ Remove brake-pedal mounting bracket to insert boot.





Fig. 2 Checking non-return valve
^ Non-return valve -A- should be open and allow passage of air in direction of (arrow) (blow into valve).
^ Valve should remain closed in opposite direction and not allow air to pass.

Note: Pay attention to correct installation position.