2.11. Removal of air from brake system
Use only fresh brake liquid DOT 3 or DOT 4.
Prorolling of a hydraulic drive of brakes is necessary for removal of air considerably reducing efficiency of braking. Air can get to a hydraulic drive owing to system depressurization at repair, replacement of separate knots or a brake liquid. In air presence in a drive specify the increased course of a pedal of a brake and its "softness". Before air removal check up tightness of all knots of a drive of brakes and their connections.
In the course of prorolling of brake system level of a brake liquid should not fall below the middle пополнительного a tank.
Prorolling is carried out with the assistant.
Prorolling of brakes carry out in the following sequence:
1 — the back right working cylinder of a brake;
2 — the back left working cylinder of a brake;
3 — a forward right support of a brake;
4 — a forward left support of a brake.
Lift the car.
Fig. 2.39. An arrangement of the union of prorolling and a dustproof cap on a support of a forward brake
Remove a dustproof cap from the prorolling union, clear it, put on it one end of a pure transparent hose, its other end lower in the capacity partially filled with a brake liquid (fig. 2.39
Fig. 2.40. Removal of air from brake system; one end of a pure transparent hose is established on the prorolling union; its other end is lowered in the capacity partially filled with a brake liquid
Sharply press a pedal of a brake
of 3-5 times with an interval of 2-3 seconds, and at the pressed pedal of a brake turn on on half of turn the prorolling union. Continuing to press a pedal, supersede a liquid being in system together with air through a hose in capacity. After the pedal will reach extreme forward position and вытекание
liquids through a hose will stop, will screw the prorolling union home. Repeat these operations, the air outlet from a hose will not stop yet.
Keeping a pedal in the pressed position, screw up the prorolling union against the stop and remove a hose from the prorolling union.
Wipe the union of prorolling and establish a protective cap.
Repeat these operations for other wheels.