Two hydraulic systems are used in Niva VAZ-2121/2131 and Chevrolet-Niva cars, which require pumping during operation in order to remove air. It is a hydraulic brake and clutch drive system. If there are air bubbles in them, the brakes may not work or the clutch is not fully disengaged, as well as failures of the clutch and brake pedals.
Necessary
- - transparent hose;
- - capacity;
- - clutch fluid and brake fluid.
Instructions
Step 1
Bleed the hydraulic brake system together with an assistant, installing the Niva on a viewing pit or overpass. Remove air first from one circuit of the system, then from the other. Always start with the right rear brake cylinder. Remove the bleed cap from the bleed nipple. Take a transparent hose and put one end of it on this fitting. Dip the other end into a container with brake fluid.
Step 2
The assistant must press the brake pedal 3-4 times at intervals of 1-2 seconds and hold it down. Using an 8 mm T-wrench, unscrew the bleed nipple ½ to ¾ turn. Under pressure in the system, part of the brake fluid and the air in it will escape into the container. The pedal will sink to the floor. Escaping air bubbles will be visible through the transparent walls of the hose. Screw on the bleed nipple and repeat the procedure several times until no more air bubbles come out. At the same time, constantly monitor the level of brake fluid in the master cylinder reservoir and add it as needed.
Step 3
After bleeding the rear right cylinder, go to the left and then to the front wheel cylinders. To bleed the front cylinders, remove the upper union cap and carry out the procedures as described. To bleed another circuit of the brake system, bleed air from the lower fittings. In the absence of air in the hydraulic system, the brake pedal should be rigid and recessed when pressed no more than half of the maximum travel.
Step 4
To bleed the clutch hydraulic system, clean the reservoir and the union from dirt. Check the fluid level in the drive reservoir and top up if necessary. Follow the recommendations described in point 1 for the clutch. At the same time, make sure that the fluid level in the reservoir of the hydraulic drive is above the opening of the tube connecting the reservoir to the master cylinder so that the end of the hose is constantly immersed in the fluid of the hydraulic drive.
Step 5
If, despite prolonged pumping, air bubbles emerge from the hose, check that the connections are secure; Check for cracks or leaks in the fittings on the tubing. Air may enter through damaged O-rings on the master or slave cylinder.
