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Bleeding the hydraulic brake system
Bleeding brake system
A warning  The brake fluid used in the hydraulic system of brakes is poisonous, so if it gets on your skin, wash immediately with a place with plenty of water. If the liquid gets into your eyes or inside the body, you must seek medical advice immediately. Some liquids have property easily to ignite and can light up even from contact to hot knots of the car. In addition, the fluid used in the hydraulic system of brakes, dissolves a paint and plastic, therefore at liquid hit on a paint and varnish covering of the car wash it with plenty of water. Also, this fluid is hygroscopic, ie. E. Absorbs moisture from the air and therefore a liquid, stored long time in open ware, it is not recommended.
Bleeding the hydraulic system of brakes is necessary for removal of air which considerably reduces braking efficiency. The air can get into the hydraulic system owing to system depressurization at repair, replacement of separate knots or a brake liquid. In air presence in a drive specifies the increased brake pedal travel and its softness. Before air removal check up tightness of all knots of a drive of brakes and their connections. Never use brake fluid again. When performing the pumping of the brake system does not let the brake fluid level drop below the middle of the tank. If brake fluid is gone from the system due to a leak in the system, find the cause and repair the leak before proceeding. If the hydraulic system is disconnected in part, and have taken appropriate precautions to prevent the further loss of fluid can be pumped only part of the system. Pumping can be performed with an assistant or by yourself, set pumping the brake system. Always act according to instructions. It is recommended to use a set whenever possible, as it greatly simplifies the process of pumping. If set to no bleeding, you should stock up on clean containers and clear plastic tube of appropriate length, which should fit dress for the bleeder valve. This will require the assistance of another person.
The sequence of pumping
If produced only a partial disengagement of the hydraulic brake system and follow the proper precautions, it is enough to pump over only this part of the system. When all is done pumping hydraulic braking systems, pumping each contour begin with the front wheel on models without antilock brake system. On models with anti-lock braking system in the first bleed the front loop.
Bleeding - the basic method (two persons)
| PERFORMANCE ORDER | | 1. Remove the dust cap from the wheel cylinder bleeder, clean it and put on it the pure transparent hose which other end lower in the capacity partially filled with brake fluid. The tank should be at least 300 mm above the bleeder. This prevents the ingress of air into the cylinder through a carving bleeder. | | 2. Sharply press the brake pedal 3-5 times at intervals of 2-3 seconds, unscrew half a turn the bleeder valve when the pedal is depressed. Continuing to press the pedal box in the expel liquid together with air through the hose into the container. After the pedal will reach extreme forward position, and leakage of fluid through a hose will stop, will screw the bleeder valve to failure. Repeat these steps until no air outlet hose. | | 3. While holding the pedal down, tighten the bleeder valve until it stops and remove the hose. | | 4. Clean the bleeder valve and install the protective cap. | | 5. Repeat these steps for the other wheel. |
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A warning At air removal constantly watch presence of a brake liquid in a tank, without supposing an exposure of its bottom as thus in air again will get. In the absence of air in the brake pedal should pass about half of course. To eliminate the influence of the vacuum brake booster pumping the brakes, air removal make at the idle engine.
Bleeding - using set with the unidirectional valve
The kit consists of a tube with the attached one-way valve, which eliminates the possibility of return to brake system remote brake fluid with air bubbles. In some sets has a transparent container, wherein air bubbles are easily seen in the brake fluid.
| PERFORMANCE ORDER | | 1. Remove the dust cap from the wheel cylinder bleeder, clean it and put it with the hose set. Loosen half turn the bleeder valve. Gently press the brake pedal to stop and slowly release it to its original position. Repeat this process until the bleeding is from the union will not be a brake liquid without air bubbles. | 2. Tighten the bleeder valve until it stops, remove it from the tube and put the dust cap.
A warning At air removal constantly watch presence of a brake liquid in a tank, without supposing an exposure of its bottom as thus in air again will get.
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Bleeding - using a set of squeezing
Using a set of pumping pressure required to feed him the compressed air, which can be used to inflate the tire of a spare wheel.
| PERFORMANCE ORDER | 1. Reduce the tire pressure to the value specified in the instruction manual kit.
A warning VW recommends the use of compressed air is supplied at a pressure of 2 bar.
| | 2. Connect filled with brake fluid container to popolnitelnomu master cylinder reservoir. Pumping process begins after unscrewing the bleeder on the half turn. After that stop the outflow of brake fluid with air bubbles and will follow only clean brake fluid, tighten the bleeder valve until it stops. |
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When pumping this method requires a large amount of hydraulic fluid to prevent air from entering the master cylinder during bleeding that often occurs if you do not maintain the level of liquid in a tank. Pumping pressure is particularly effective when the system is difficult to pump or when undergoing a complete pumping system during normal brake fluid change.
All methods
| PERFORMANCE ORDER | | 1. After completion of the pumping press firmly on the brake pedal, thus it should pass about half of course. Wash away all traces of the spilled brake liquid also tighten unions pumping demanded moment, then establish on them dustproof caps. | | 2. Check the brake fluid level in the brake system popolnitelnom tank and, if necessary, top up the brake fluid. |
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A warning Remote brake fluid should not be used anymore. Pure brake fluid must be kept in a sealed vessel, since it is highly hygroscopic, which lowers the boiling point and deteriorates specifications brake fluid.
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