Note. The master brake cylinder is not repairable.
Removing
1. Remove the decorative engine cover.
2. Remove the air filter assembly (see the relevant section in chapter Intake and exhaust system).
3. Remove the battery and its support plate.
4. Using special equipment to bleed the brake system (VAS 5234), remove the brake fluid from the expansion tank of the master cylinder.
5. Place a clean cloth around the engine.
6. Disconnect from expansion tank (4) brake master cylinder hydraulic clutch release hose (2), as shown in the figure below.
7. Mute (1) hose (2) hydraulic clutch release using a special plug (Т10249), as shown in the figure below.
8. Raise the hose (2) and put aside.
9. Disconnect the wiring harness connector (1) from the brake fluid level indicator sensor in the expansion tank of the master cylinder, as shown in the figure below.
10. Remove the fixing pin from the master brake cylinder (1) in the direction of the arrow as shown in the figure below.
11. Remove the expansion tank assembly from the master brake cylinder.
12. Disconnect the wiring harness connector from the brake light switch (2), as shown in the figure below.
13. Put alignment marks on the brake pipes (1), shown in the figure below.
14. Unscrew the connecting nuts and disconnect the brake pipes from the master brake cylinder (1), as shown in the figure below.
15. Plug the outlet holes of the main brake cylinder with special plugs from the repair kit (1H0 698 311 A).
16. Unscrew the nuts securing the master brake cylinder to the housing of the vacuum brake booster (arrows), as shown in the figure below.
17. Gently pull and disconnect the brake master cylinder (1) from the vacuum booster.
18. Remove the stoplight switch.
Installation
Note.
Always after disassembly, it is necessary to replace the gasket between the brake master cylinder and the vacuum booster. Be extremely careful when installing the master cylinder on the vacuum booster - make sure that the booster rod is installed in the master cylinder properly.
Always fill the brake system with fresh brake fluid.
1. Installation is made in reverse order to removal.
Top up the expansion tank of the master cylinder with fresh brake fluid.
Bleed the brake system.
Bleed the hydraulic clutch release.
Install the air filter assembly.
Install the battery and battery support plate.
Install the engine top cover.