Brake booster
1. Master cylinder; 2. Hose; 3. Gasket; 4. Fork axle; 5. Fork; 6. Cotter pin; 7. Vacuum amplifier; 8. Gasket; 9. Splitter on ABS brakes
Checking the operation of the vacuum booster
1. Press the brake pedal several times with the engine off. The pedal stroke should not change with each press.
2. Press the pedal and start the engine - with a working booster, the brake pedal should move forward a little.
Leak test
1. Start the engine, stop after 1-2 minutes. Slowly depress the pedal several times. On a working amplifier, the pedal travel should gradually decrease with each press.
2. Start the engine and step on the pedal. Keeping the pedal depressed, stop the engine - within 30 seconds after stopping, the position of the pedal should not change.
If the amplifier is faulty, then it will lie down to be replaced, the repair of the unit is impossible even in a car service.
Removing
1. Remove the master cylinder (see subsection 10.9.).
2. Remove the gasoline vapor recovery tank (see subsection 7.2.20.).
3. Remove the air filter (see subsection 6.11.).
4. Carefully disconnect the vacuum hose from the booster.
5. Working inside the cabin, remove the steering column cover (see subsection 11.24.).
6. Having illuminated with a lantern, find the plug of the pusher of the vacuum booster in the place of fastening on the brake pedal. Unpin and remove the fork axle.
7. Remove the four nuts that secure the brake booster to the bulkhead of the engine compartment.
8. Apply the booster and remove when the studs come out of the holes in the baffle.
Installation
Installation is made in sequence, return to removal.
If a new unit is installed, then adjust the gap between the pusher of the brake master cylinder and the booster pusher. To do this, do the following.
1. There should be no gap between the pushers of the vacuum booster and the master cylinder. If the gap is non-zero, then the brake pedal stroke increases. If, on the contrary, the pusher of the amplifier rests against the pusher of the cylinder, then the wheels may not be braked.
2. Measure the protrusion of the pushrod above the gasket on the booster housing. This is size A.
3. Measure the distance from the end face of the master cylinder to the plane of the flange. This is size B.
4. Measure the distance from the end face of the master cylinder to the bottom of the piston recess. This is size S.
6. The clearance between the pusher and the piston is (B - C) - A and must be equal to 0. If necessary, adjust the protrusion of the pusher of the vacuum booster.
7. To adjust the pusher, squeeze the pusher by the knurled neck and rotate the tip of the pusher to set protrusion A so that the gap is equal to B - C. Check the gap again. Repeat the adjustment if necessary.
8. When finished, install the master cylinder, attach the tubes, adjust the pedal height and free play. Bleed the air from the hydraulic drive.