UAZ -374195 Operation Manual page 93

no stroke, as well as poor or excessive stroke, the valve or its drive has
malfunctions.
When inspecting the hydraulic drive pay attention to protective boot
1, to the position of gauge plug 15 and to brake fluid leaks from it. The
plug shall normally be sunk into the housing orifice of the valve. If the
plug comes out or the brake fluid leaks, the valve must be replaced.
The protective boot shall be tightly installed in the seats of the piston
and the housing shall have no damages.
During the operation and during rear springs replacement adjust the
force of flexible arm 5 (Fig. 9.31) to the valve piston. For adjustment
do the following:
1. Install the vehicle on an even level ground.
2. loosen locknut of adjusting bolt 4 (Fig. 9.31) and unscrew the
bolt for 2–3 turns.
3. Screw bolt 4 (Fig. 9.31) until it touches piston tail 17 (see Fig.
9.30) of the valve.
4. Tighten the locknut.
5. Check the stroke of the valve piston (see above).
6. Check the adjustment correctness in motion of the vehicle. While
going on a straight level road with a dry surface, brake the vehicle until
wheels block. If the valve operates properly and drive adjustment is done
correctly, the front wheels shall be blocked slightly earlier than the rear
ones. If the rear wheels are blocked earlier, unscrew bolt 3 for 1–2 flats
of the bolt head and check the brakes in motion again.
The pedal travel is adjusted by changing the length of vertical drive
rod 9 (Fig. 9.32). The pedal full travel is 200 mm. The pedal free travel
shall be 5–14 mm.
Check the pedal free travel when the engine is stopped.
Fill the brake system (for example, when replacing a hose or a
pipe) as follows:
Fig. 9.31. Proportioning Valve Drive:
1 — proportioning valve; 2 — bracket (base);
3 — drive lever; 4 — adjusting bolt; 5 — flexible
arm; 6 — arm pillar
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