Note. If air enters the system as a result of a violation of its tightness, the cause of the malfunction must first be eliminated.
If air gets into a single wheel cylinder, it is enough to bleed only the corresponding caliper. If air enters the system path as a result of an excessive drop in the liquid level in the GTZ reservoir, as well as after removing / installing the latter, the entire system is pumped. This also applies to the case of performing maintenance procedures requiring the dismantling of the hydraulic modulator.
Pumping without the use of a special device
Attention! When any of the chambers of the GTZ tank is completely empty (for example, as a result of a leak in any of the tracts, or if the liquid was not added to the tank after performing maintenance procedures) the air sucked into the tract inevitably enters the ABS pump - in this case, pumping should be carried out in a service station using a special device.
1. Check the level in the brake fluid reservoir, correct if necessary (see chapter Checking fluid levels, leak control).
Attention! During the procedure, the liquid in the GTZ tank should not drop excessively - periodically adjust its level by adding fresh!
2. Remove the dust cap from the bleed valve from the appropriate brake caliper. Pull a piece of transparent hose over the valve, lower the free end of it into a drain container partially filled with brake fluid to prevent air from being drawn in during pumping.
3. Using a ring wrench, carefully loosen the valve.
4. Ask an assistant to depress the foot brake pedal several times and then lock it in the lower position.
5. Open the valve - the brake fluid will begin to flow into the drain container. If the pressure drops, close the valve and repeat the procedure.
6. Continue pumping until the fluid pumped out of the circuit is completely free of air bubbles / fresh fluid starts to be pushed out of the hose (in case of replacement), - do not forget to check and, if necessary, correct the liquid level in the GTZ reservoir.
7. When finished priming, tighten the valve, remove the hose and replace the dust cap.
8. If necessary, proceeding in a similar manner, pump the calipers of the remaining brake mechanisms - do not forget to periodically add fluid to the GTZ reservoir.
9. Finally, correct the fluid level in the GTZ reservoir (see chapter Checking fluid levels, leak control) and check the proper functioning of the brake system and clutch.
Pumping using a special device
The connection of the device must be carried out in strict accordance with the instructions of its manufacturers, - the procedure should be entrusted to car service specialists.
Bleeding the brake system with a special tool