6.1.4. Removal of air from the brake system

ATTENTION Brake fluid is extremely aggressive in relation to the painted surfaces. If liquid incidentally got on the painted surface, immediately wipe it and clear the painted surface.

Removal of air is necessary every time when it gets to hydraulic system. Pipelines of hydraulic system are located on diagonal. In case of a detachment of the brake highway or a hose from the brake mechanism of a wheel, it is necessary to remove air since both ends of the removed pipeline or a hose. In case of removal of any connecting detail of the main cylinder or other connecting detail between the main cylinder and the brake mechanism of a wheel it is necessary to remove air from all 4 brake mechanisms of wheels.

Fig. 6.11. The scheme of removal of air from a contour of the brake mechanism: 1 – support of the brake mechanism of the right wheel; 2 – support of the brake mechanism of the left wheel; 3 – brake cylinder of the right wheel; 4 – brake cylinder of the right wheel

NOTE Begin removal of air with the wheel brake cylinder located further everything from the main brake cylinder, and then remove air from the brake mechanism of a forward wheel of the same contour of the brake system. Make the same on other contour of the brake system (fig. 6.11).

Fill the tank of the main cylinder with brake fluid and you watch that during all procedure of removal of air from system the tank was filled with liquid not less, than half.

Brake fluid: DOT3.

Fig. 6.12. Preparation for pumping

Remove a pumping union cap. Attach a vinyl tube 1 to the union and lower other its end in a container 2 (fig. 6.12).

Press a brake pedal several times and then without releasing a pedal, unscrew the union from one third to a half-turn.

After liquid ceases to go out of the cylinder, tighten the union.

Fig. 6.13. Pumping of brakes

Repeat pumping until the tube does not leave air bubbles (fig. 6.13) any more.

Fig. 6.14. End of pumping

After that tighten the union without releasing a pedal of a brake (fig. 6.14).

Union of a support of the forward brake mechanism: 8,5 N · m (for production NISSIN supports).

Union of a support of the forward brake mechanism: 11,0 N · m (for all supports, except supports of the made NISSIN).

Union of the cylinder of a back wheel: 8,5 N · m.

Establish into place an union cap.

After completion of the procedure of removal of air lift liquid pressure in the highway and check leak existence.

Fill up liquid level in the tank to norm.

Check rigidity of a pedal of a brake. If a pedal "soft", repeat all procedure of removal of air.