3.27. Replacement of brake fluid

It will be necessary for carrying out work for you:

Repeatedly do not apply the brake fluid which was in the use. Old brake fluid is much more darkly fresher. It allows to distinguish them easily.

Brake fluid through a time of brake hoses and an air vent of the tank absorbs moisture. Thereof liquid boiling temperature in use decreases. At big load of brakes it can lead even to steam formation that reduces efficiency of action of brakes.

Brake fluid owes each 2 years, it is desirable in the spring, to be replaced with new. At the frequent movement in the mountain area, liquid needs to be replaced more often.

On HUNDRED air from the brake system, as a rule, is removed on the special device. However it can be done also without use of the specified device. At the same time the brake system is pumped over by a brake pedal. For this purpose participation of the assistant is required.

If in the course of removal of air from the brake system liquid level sharply decreases, then there is a suction of the air getting to the pump ABS. In this case removal of air needs to be made on HUNDRED with use of the special device. When replacing any brake hose air needs also to be removed from system on HUNDRED. Until it is made, it is impossible to use the car.

Sequence of removal of air:

  1. The support is back right
  2. The support is back left
  3. The support is forward right
  4. The support is forward left

Pay attention to remarks according to safety measures at the treatment of brake fluid, address the Section Removal of Air from the brake system.

Cover (1) of the tank of brake fluid and tube under a carving stopper (shooter) for removal of brake fluid by means of a rubber pear


  1. By means of a pear remove brake fluid from the tank, having left a layer of liquid about 10 mm thick at the bottom of the tank. Do not delete all liquid from the tank, otherwise air will get to the brake system.
  1. Fill the compensation tank with new brake fluid to a tag the MOVE.
  1. Carefully, not to curtail, open the union of removal of air. It is recommended in 2 hours prior to removal of air to process the union means for removal of a rust. If the union does not open, then operation on removal of air from the brake system should be charged to a workshop.

  1. On the right back support of the disk wheel brake mechanism put on a pure transparent hose the union of removal of air and insert it into a suitable vessel.
  2. Ask the assistant to squeeze out repeatedly a brake pedal until counter-pressure to pressing of a pedal becomes notable. Press a pedal and open the union of removal of air. Close the union after the brake pedal rests against a body floor. Take away a leg from a pedal. Repeating this process, pump out about 400-500 ml of old brake fluid.
  3. Close the union of removal of air and fill in new brake fluid in the compensation tank.
  4. In the same way pump out old brake fluid from other supports or wheel brake cylinders, observing the sequence stated above.

The merged brake fluid anyway has to be pure and without air bubbles. From each brake support it is necessary to pump out about 400-500 cm of the 3rd old brake fluid.

  1. Hand over old brake fluid on special point on reception of the fulfilled fuels and lubricants.
  2. Press a brake pedal and check a free wheeling. It should not exceed 1/3 courses of a pedal.
  3. Fill in brake fluid in the tank to earlier existing level.
  4. Screw a stopper on the tank.
  5. Carry out reliability inspection:
    • Whether brake pipelines and hoses are fixed?
    • Whether there are brake hoses in holders?
    • Whether unions of removal of air are tightened?
    • Whether enough liquid is filled in in system?
  6. On the working engine check tightness of system. For this purpose press about 10 times a brake pedal with effort of 200 - 300 N (there correspond 20 - 30 kg). The pedal of a brake should not leave back. Check all connections for tightness.
  7. In conclusion check action of brakes on the road with not heavy traffic of transport. For this purpose it is necessary to make not less than one strong braking, having checked ABS action (a sign of work of ABS the brake pedal pulsation when braking is).

You watch the transport going following your car. The effect of action of ABS is best of all shown on the unpaved road.

It is not necessary to pour out brake fluid together with household waste or somewhere to other place.