Master brake cylinder (Audi A4 B5)

The brake master cylinder is, to some extent, the main element of the brake system. It is located at the rear left of the engine compartment and signals the brake calipers to begin braking. More detailed information about its design and operation can be found at the beginning of this chapter.

Removal the master brake cylinder

1. Suck out the brake fluid from the reservoir; to do this, remove the strainer from the filler pipe.

2. Disconnect the brake fluid level indicator connector from the reservoir, the same applies to the clutch cylinder wire.

3. Remove the reservoir from the master cylinder.

4. Remove the brake booster vacuum hose.

5. Mark the brake hoses on the master cylinder for subsequent installation and unscrew them.

6. Unscrew both fastening nuts (not TORX bolts) at the rear of the master brake cylinder.

7. Carefully and without bending, remove the brake master cylinder from the brake booster.

8. When assembling, install a new sealing ring between the brake booster and the brake master cylinder.

9. Carefully place the master cylinder on the brake booster. If necessary, have an assistant gently press the brake pedal to help slide the master cylinder onto the push rod.

10. Tighten the fastening nuts to 50 Nm.

11. Tighten the brake hoses to 15 Nm.

12. Before pressing the expansion tank, moisten the inside of the sealing plug of the expansion tank connecting pipe with brake fluid.

13. Bleed the brake system.

14. If necessary, bleed the clutch hydraulic system.

Text provided by the online resource: AudiManual.ru