The pressure regulator is attached to the left side member of the frame
It adjusts the brake fluid pressure in the rear wheel brake circuit, depending on the vehicle load, which improves directional stability when braking
By monitoring rear axle loading through the load spring, it limits the fluid pressure in the rear brake circuit.
In case of failure, the regulator is replaced.
After replacing the adjuster or elements of the rear suspension, it is necessary to re-adjust the position of the load spring relative to the rear axle.
Replacing the regulator
Drain the brake fluid from the rear circuit (see Bleeding the brake system, replacing the brake fluid).
Disconnect the load spring from the rear axle.

Using the “12” key, we unscrew the two fittings of the brake pipes.

Keeping the bolts from turning with the “12” head, use the “13” key to unscrew the two nuts of the regulator fastening bolts

We take out the bolts and remove the regulator from the car along with the bracket

Using the “13” key, we unscrew the two nuts

Remove the bracket from the regulator

Use the “12” key to unscrew the fixing bolt

Removing the load spring

Removing the pin

Remove the lever axis
Remove the lever

Having moved the parts to the new regulator, install it in reverse order.
Bleeding the system and adjusting the regulator.
Adjusting the slider

With the “13” key, unscrew the strut nut and disconnect the load spring from the rear axle.
We lower the load spring down.

Use the “14” key to unscrew the locknut of the adjusting bolt

Using the “10” key, rotate the adjusting bolt

Set the distance between the center of the bracket hole and the axis of the regulator within:
- 28-32mm (for 4x2 buses);
- 36-40mm (for 4x4 buses);
- 13-17 mm (for other types of vehicles).
While holding the adjusting bolt, tighten the locknut.
We fix the lower end of the rack on the rear axle bracket.
After adjustment, check the operation of the regulator, for which, at a speed of 50-60 km / h on a hard, dry road surface, we vigorously press the brake pedal, while the assistant should watch the wheels from the side.
With a good and properly adjusted regulator, there should be a slight lead in blocking the front wheels relative to the rear.
If the opposite happens, then, having unscrewed the locknut of the adjusting bolt, unscrew the bolt by half a turn.
If the front wheels lock before the rear wheels, turn the adjusting bolt half a turn and tighten the locknut.
