Removal of air from a hydraulic drive of brakes

Bleeding of the hydraulic drive of the brakes must be carried out in all cases when, during the performance of any work, there is a violation of the tightness of the hydraulic drive. The hydraulic brake actuator should also be bled when the brake pedal becomes «soft» or when multiple brake applications are required for effective braking.

Warning

1. It is forbidden to unscrew the union for bleeding the circuit of the hydraulic drive of the brakes of the rear wheels with the brake pedal depressed or the pressure accumulator charged.

2. The pressure of the charged accumulator of the rear wheel circuit pressure is 180 kgf/cm². Therefore, before carrying out any work on the brake system, discharge the pressure accumulator by pressing the brake pedal at least 20 times.

3. When pumping the hydraulic drive, it is forbidden to turn on the ignition, except for specially indicated cases.

4. To fill and restore the level of the brake fluid, use only fresh fluid of the specified brand.

5. When pumping, constantly restore the normal level of fluid in the tank.

Bleeding the front wheel circuit is carried out on both front wheels, for which remove the protective caps from the air outlet fittings. Clean the fitting from dust and dirt.

Put a transparent tube on the head of the fitting of the brake mechanism of the right wheel, and lower its free end into a vessel filled with ⅓ clean brake fluid. Depress the brake pedal to pressurize the brake gas system. If no resistance is felt when depressing the pedal, depress it slowly and without interruption until depressing does not require any force. Loosen the fitting ½ turn with the pedal depressed to the full. After that, the assistant should slowly press the brake pedal and slowly release it, while the liquid, together with air, will be forced out of the system through the hose into the vessel. Repeat this process until. until bubbles stop coming out and clear fluid comes out of the hose, keep the pedal depressed and tighten the air outlet fitting tightly. Remove the hose and put on the fitting a protective cap.


Repeat operations for the left wheel.

After pumping, restore the level of brake fluid in the reservoir if necessary. Do not use the fluid drained from the system to fill the reservoir, as it is saturated with air, contains a lot of moisture and may be contaminated. Bleeding the rear wheel circuit is carried out on both rear wheels, to do this, remove the protective cap from the bleeder fitting, put a transparent tube on its head and lower the free end of the tube into a vessel filled with brake fluid. Press the brake pedal, while the pedal is depressed, unscrew the bleeder screw and turn on the ignition, which will cause the ABS pump to turn on. Wait for the moment when the air bubbles with the liquid stop coming out, then release the brake pedal and tighten the bleeder screw.

Switch off the ignition and wait until the ABS pump stops before proceeding to bleed the other rear wheel circuit.