The presence of air in the drive is indicated by an increased brake pedal travel and its "softness". Before removing air, check the tightness of all brake drive units and their connections.
Bleed the entire brake drive system in the following sequence:
- right front wheel;
- left front wheel;
- right rear wheel;
- left rear wheel.
1. Remove the dust cap from the wheel cylinder bleeder nipple, clean it and put a clean transparent hose on it, the other end of which is lowered into a container partially filled with brake fluid. The container should be at least 300 mm above the bleeder nipple. This prevents air from entering the cylinder through the thread of the bleeder nipple.
2. Press the brake pedal sharply 3-5 times with an interval of 2-3 seconds, unscrew the bleed nipple by half a turn with the pedal pressed. Continuing to press the pedal, force out the liquid in the system together with the air through the hose into the container.
3. After the pedal reaches the extreme forward position and the fluid stops flowing out through the hose, screw the bleed nipple all the way in. Repeat these operations until air stops flowing out of the hose.
4. While holding the pedal down, tighten the bleed screw until it stops and remove the hose.
5. Wipe the bleed nipple clean and install the protective cap.
6. Repeat these operations for the other wheels.
Caution! When removing air, constantly monitor the presence of brake fluid in the reservoir, not allowing its bottom to become exposed, since this will again introduce air into the system.
7. If there is no air in the brake system, the pedal should travel about half of its travel. To eliminate the influence of the vacuum booster on the bleeding of the brakes, bleed the air with the engine not running.