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Bleeding the brakes
Bleeding the brakes is necessary for removal of air from the hydraulic circuit, which greatly reduces the effectiveness of the service braking system. Air can get into the hydraulic system depressurization due to the repair or replacement of individual units, and replace the brake fluid. The presence of air in the brake actuator indicates increased brake pedal travel and its "softness". Priming need new brake fluid. The company ?«Volkswagen?» recommends a brake fluid brand ?«FMVSS 116 DOT 4". Before removing the air from the brake system check the tightness of all knots of a drive of brakes and their connections, clean the cover and the area around the reservoir cap thoroughly clean the bleed screw. Bleeding brake system is necessary after each repair brake system, if the opening drive of the hydraulic system of brakes. Ride is recommended to start with the addition of a support, which was subjected to replacement or repair. Observe the following sequence pumpable brake: - Rear right brake caliper; - Rear left brake caliper; - Front right brake caliper; - The front left brake caliper.
A warning During pumping constantly watch levels of brake fluid and keep it at the level of "Max." |
Note It is not recommended to apply the liquid discharged from the system for filling the tank, as it is filled with air, it has a lot of moisture and possibly contaminated. |
Pumping the brake sequence is as follows: - Remove the dust cap, clean the bleed screw and put on him a rubber hose to drain the liquid, and its free end in the lower glass container partially filled with brake fluid; - Ask the assistant several times sharply push the brake pedal until it appears sharp counter; - Unscrew by 1/2 - 1/4 turn fitting when the pedal is depressed. Continuing to press the brake pedal, supersede a liquid being in system together with air through a hose into the vessel. Brake pedal "will go" into the floor, hold it in this position, tighten the bleeder valve;
Note Make sure that the hose end is continuously immersed in the liquid. |
- Repeat this operation as long as no air bubbles in the air from the hose; - Top up the brake fluid in the reservoir, maintaining the level near the mark "Max"; - Holding the brake pedal down, tighten the fitting to the full and put the protective cap; - Repeat the operation for the other wheel; - Check the rubber seal tank; - After pumping refill the brake fluid in the reservoir up to the mark "MAX"; - Check the tightness of all the system connections; - Make a test drive during which caution. Replacing brake fluid Replacement of brake fluid every two years. On HUNDRED brake fluid replacement carried out by a special device for filling and bleeding the brake system. The container unit is filled with compressed air at a pressure of about 400 kPa. To replace the fluids and pumping device is set equal to the operating pressure of 100 kPa. However, the replacement of the brake fluid can be made independently. This will require approximately 2 liters of fresh brake fluid specified brand. In order for the hydraulic drive system when replacing brake fluid is air, and was spent minimal amount of time for this operation, follow these guidelines: - Proceed in the same manner as when pumping the brakes, but use a hose with the glass tube at the end, which is lower in a container with brake fluid; - Pressing the brake pedal pumping out the old brake fluid as long as the tube does not seem the new liquid, then perform two full stroke the brake pedal and hold it down, tighten the fitting; - Always keep the brake fluid level in the reservoir and top up the liquid in a timely manner to the level of "Max"; - Repeat this operation on each brake cylinder in the same manner as when pumping; - After replacing the brake fluid reservoir to the maximum fill level and check the brakes while driving, being careful.
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