66
1 - protective cover; 2 - lock ring; 3 - sleeve; 4 - piston O-ring; 5, 7 - piston spring washer; 6 - piston spring; 8 - gasket; 9 - housing
bushing; 10 - collar; 11 - plug; 12 - plug gasket; 13 - blow-off valve; 14 - cap; 15 - plug; 16 - housing; 17 - piston
When the brake pedal is depressed, the pressure regulator piston 17 (Fig. 9.30) should rise 1.7 - 2.3 mm out of the
housing. Lack of piston stroke or insufficient or excessive piston stroke indicates a malfunction of the regulator or its
actuator.
When inspecting the hydraulic actuator, check the condition of the protective cover 1 and the location of the gauge
plug 15 and leakage of brake fluid from underneath. In its normal state, the plug should be recessed into the hole in the
regulator body. If the plug protrudes from the hole and the brake fluid leaks, it is necessary to replace the regulator.
The protective cover must be firmly seated in the piston and housing seats and must have no cracks.
During operation and when replacing the rear springs it is necessary to adjust the force of the elastic lever 5 (Fig.
9.31) on the regulator piston. Adjust the headlights as follows:
1. Park the equipped vehicle on a flat, horizontal surface.
2. Loosen the locknut of the adjusting bolt 4 (fig. 9.31) and loosen the bolt by 2-3 turns.
3. Screw the bolt 4 (Fig. 9.31) until it touches the piston shank 17 (Fig. 9.30) of the regulator.
4. Tighten jam nut.
5. Check the stroke of the regulator piston (see above).
6. Check that the adjustment is correct when the vehicle is in motion. To do this, while driving on a straight
horizontal road section with dry asphalt surface, brake the car until the wheels are locked up. If the regulator is operating
properly and the actuator is adjusted correctly, the front wheel shall lock a bit ahead of the rear wheels. If the rear wheels
are locked up first, additionally unscrew bolt 3 on 1-2 faces of the bolt head and repeat the test when the vehicle is moving.
Fig. 9.31 Pressure regulator actuator:
1 - pressure regulator; 2 - bracket (base); 3 - drive lever; 4 - adjusting bolt; 5 - elastic lever; 6 - lever post
Pedal free stroke adjustment
shall be carried out by changing the length of the vertical rod 9 (Fig. 9.32) of the
driver. Brake pedal full travel, 200 mm Pedal free travel should be 5-14 mm.
Check the pedal's free travel with the engine not running.
Fill the brake system (e.g. when replacing a hose or line) as follows:
CAUTION! Filling the brake system of vehicles equipped with ABS must be done at the service station, because this
requires additional diagnostic equipment.
1. Check the tightness of all hydraulic brake system connections and the condition of the flexible rubber hoses.
2. Clean off dust and dirt bypass valves and protective caps of wheel cylinders and regulator.
3. Remove the radiator frame, clean surface of the master cylinder tank from dust around the cover and unscrew the
cover. Fill the reservoir with brake liquid up to the “MAX” mark.
4. Press the brake pedal several times to eliminate the effect of the vacuum present in the brake vacuum servo.
5. Pump the brake system.
