Contents: Removal ⇓ Installation ⇓
Fig. 6.22. Dismantling components of the master brake cylinder: 1 – brake fluid level sensor connector; 2 – brake line; 3 – hose (models with manual transmission); 4 – master cylinder; 5 – sealing ring
Removal
Caution! Do not allow brake fluid to come into contact with painted surfaces. If brake fluid does come into contact with a painted surface, wash it off immediately.
Drain the brake fluid.
Disconnect the brake fluid level sensor connector.
Disconnect the brake line, disconnect the brake pipes from the master cylinder.
Fig. 6.23. Disconnecting the hose from the brake fluid reservoir
Disconnect the hose from the brake fluid reservoir by pressing at the point indicated by the arrow in the figure (Fig. 6.23).
Unscrew the two mounting nuts, remove the nipple, the master brake cylinder and the gasket.
Installation
Caution: Always install the brake booster tappet shim before performing any verification measurements or adjustments.
Fig. 6.24. Installing a special device on the brake booster
Install the special tool to the brake booster as shown in Figure 6.24 and tighten to the specified torque.
Tightening torque: 9.8–16.0 Nm.
Fig. 6.25. Creating a vacuum in the brake booster
Using a vacuum gauge, create a vacuum in the brake booster equal to 66.7 kPa (Fig. 6.25).
Fig. 6.26. Measuring the length of the pusher
Using a caliper, measure the distance L as shown in Figure 6.26.
Standard length: 22.7mm.
Fig. 6.27. Adjusting the pusher length
If the L dimension is not as shown, remove the special tool (49 E043 001) and a special device (49 B043 004) adjust the length of the pusher. Use the special tool (E043 003A) to prevent the pusher from rotating (Fig. 6.27).
Remove special tools, replace special tool (49 E043 001) and measure the distance L again.
Fig. 6.28. Diagram of correct installation of the master cylinder on the brake booster
Install the master cylinder onto the brake booster (Fig. 6.28).
Caution! If after installing the master cylinder, air does not properly escape from the brake system pipes even after the procedure for removing it, there may be incomplete release of the wheels or another defect. Remove the master cylinder and reinstall it properly.