Removal, installation and adjustment of the pressure regulator valve in the hydraulic circuits of the rear wheel brake mechanisms (Opel Astra G)

Removal

1. Support the front wheels with wheel chocks, jack up the rear of the car and place it on supports.

2. Remove the cap from the brake master cylinder reservoir, add fresh fluid to the reservoir if necessary, then place a piece of polyethylene under the cap and screw it back into place.

3. Loosen the mounting bolt and remove the tension spring bearing from the bracket on the bottom.



4. Try to remember the installation position of the spring stopper, unscrew the fastening bolt and remove the stopper. Remove the spring from the valve lever.

5. Thoroughly wipe the union connectors connecting the hydraulic tubes to the valve. Loosen the union nuts and disconnect the tubes.

6. Unscrew the mounting bolts and remove the regulator valve from the bracket on the bottom of the car, being careful not to damage the brake pipes.

Regulator valves are available in three types.

Installation and adjustment

Installation is carried out in the reverse order of dismantling the components.

[Material copied from this portal: OPELBOOK]

1. Make sure all fasteners are tightened to the required torque. Finally, bleed the brake system (see Bleeding the brake system) and adjust the valve (see below)



2. The vehicle must be unloaded, the fuel level in the tank must not exceed half, the tires must be inflated to normal pressure. On models equipped with a ride height adjustment switch valve, the pressure in the system must be at least 0.8 bar. The vehicle must be standing on wheels with a normal load on the rear axle.

3. Ask an assistant to press and quickly release the foot brake pedal - the regulator lever should jerk, confirming the correct functioning of the system. If the lever does not move, the valve should be replaced.

4. If the stopper does not touch the valve lever, move the lever forward until it stops, then release it. Now install the stopper on the spring so that the gap is completely eliminated, and fix the bolt in this position

5. Lower the vehicle to the ground.