Checking work
1. Depress the pedal and start the engine. If the pedal drops a little, then the vacuum booster is working.
2. Depress the brake pedal several times with the engine running and check that the brake pedal travel reserve is always the same.
Leak test
3. Start the engine and turn it off after a couple of minutes. Slowly depress the brake pedal several times. The brake pedal travel should decrease each time.
4. Depress the brake pedal while the engine is running, then stop the engine without releasing the brake pedal. If the pedal does not go down within 30 seconds, then the vacuum booster is tight.
Removing
1. Remove the master brake cylinder. Disconnect the vacuum hose from the booster.
2. Disconnect the booster pushrod from the brake pedal.
3. Unscrew the four fixing nuts and remove the amplifier.
Installation
1. Installation is carried out in the reverse order of removal.
2. Connect the vacuum pump to the amplifier and create a vacuum of 500 mmHg.
3. Measure the distance from the surface of the vacuum booster to the pusher - this is the distance "A".
4. Measure the distance from the mounting flange to the end of the master cylinder - this is the distance "B".
5. Measure the distance from the end of the master cylinder to the recess in the piston - this is the distance "IN".
6. Subtract the value "IN" from the meaning "B", subtract the resulting value from the value "A". The result obtained is the clearance value of the servo booster pusher.
7. Adjust the length of the pusher (1), if necessary by loosening the locknut (2) and twisting the pusher adjuster.