4.4.5. Replacement of brake fluid in hydraulic actuators of brakes and switching off of coupling

According to the recommendation of manufacturer to replace brake fluid follows through 40 thousand km of a run or in 2 years of operation (depending on what will come earlier).

Good advice
Brake fluid is very hygroscopic and absorbs moisture from air that, besides emergence of corrosion of details of the brake system, lowers temperature of boiling of the liquid, and it can lead to refusal of brakes at frequent intensive braking. Therefore we recommend to replace brake fluid every year (spring).

It will be required to you: a key "on 17", keys for nuts of the pipelines "on 9", "on 11", brake fluid, a rubber or transparent hose, a transparent vessel.

So the special key for nuts of pipelines looks.

Useful tips
Replacement of brake fluid is recommended to be made with the assistant, previously having installed the car on a viewing ditch or a platform (it will not be required to remove wheels).
Apply the brake fluids corresponding to the class DOT-4.
Sequence of replacement of liquid in brake mechanisms:
– back right;
– forward left;
– back left;
– forward right.

Do not reuse the merged liquid: it is polluted, saturated air and moisture. Always add only new liquid of that brand which was filled in before in system.
Brake fluid is hygroscopic (absorbs moisture from air) therefore it cannot be stored in an open container.
Protect the nature! Do not merge the used brake fluid to the soil or sewer system. In your area it is possible to learn about an arrangement of collection points for the fulfilled operational liquids in local authorities.

1. Turn off a stopper of a tank of the main brake cylinder.
2. Add in a tank pure brake fluid to the lower edge of a bulk mouth.

Slow down the car the parking brake and establish an antiretractable emphasis ("boots") under back wheels.

3. Clear valves of production of air of dirt and remove protective caps of valves of working cylinders of brake mechanisms of lobbies …
4. … and back wheels.
5. Put on a rubber hose the valve of production of air of the working cylinder of the brake mechanism of the right back wheel and ship the end of a hose in a pure transparent vessel.
6. The assistant has to press sharply a brake pedal four-five times (with an interval between pressing 1–2 c) then to hold a pedal of pressed.
7. Unscrew the valve of production of air on 1/2–3/4 turns. Old (dirty) brake fluid will begin to follow from a hose. The brake pedal has to reach smoothly against the stop at this time. As soon as liquid ceases to follow, wrap the valve of production of air.

Constantly you watch liquid level in a tank, without allowing its decrease to a tag of "MIN" on a tank wall. If necessary add new brake fluid not to allow hit of air in a hydraulic actuator. Thus gradual replacement of old liquid of a hydraulic system, new without drainage, is provided.

8. Replace with the same way brake fluid in the working cylinder of the brake mechanism of the left forward wheel.
9. Then replace brake fluid in the second contour (at first in the working cylinder of the brake mechanism of the left back wheel, then right forward).
10. Repeat operations 5-9 before full replacement of liquid in the drive (pure liquid without vials of air has to follow from a hose).
11. After replacement of brake fluid surely put on protective caps valves of production of air. Replace the damaged caps.
12. Check quality of the performed work: press several times a brake pedal — the course of a pedal and effort on it have to be identical by each pressing. If it not so, return to performance of operations 5-9.
13. For replacement of brake fluid in a hydraulic actuator of switching off of coupling remove a protective cap from the valve for removal of air from the working cylinder.
14. Put on a hose the valve and lower its end in capacity with a small amount of brake fluid. Ask the assistant to press a pedal of coupling of 4-5 times with intervals 2–3 with, and then to hold it pressed. Turn out the union on 3/4 turns, holding the second key the working cylinder. The hose in capacity will come out old (dirty) brake fluid.
15. Wrap the valve and ask the assistant to release a coupling pedal.
16. Repeat operations 14 and 15 before full replacement of liquid in a coupling switching off hydraulic actuator (pure liquid without vials of air has to follow from a hose).

During pumping of a hydraulic actuator periodically check liquid level in a tank of the main brake cylinder, the general for hydraulic actuators of brakes and switching off of coupling. Do not allow falling of level of liquid in it below a tag of "MIN". In due time add liquid, otherwise air will get to system and it should be pumped over.

17. Wrap the valve, put on a protective cap.
18. Add brake fluid to level between tags of "MIN" and "MAX" on a wall of a tank and wrap a stopper.
19. Establish details as it should be, the return to removal.