URAL Motorcycles 4320M, Руководство по эксплуатации, Страница: 63 / 321

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- fasten the fixation bolts 3 of the master cylinder 7 with 44-56 Nm torque (4.4-5.6 kgfm);
- regulate pedal free play by the stop 11; clearance between the tappet 13 (see figure 45) and
the piston -b should be 0.2-0.6 mm, it corresponds to pedal motion of 1-3 mm;
Regulate clutch and brake pedals on cabover trucks with eccentrics (see figure 44).
4.2.1.6 Bleeding.
When changing brake fluid or repairing gear hydraulic part bleed the sys-
tem as follows:
- fill the reserve tank 1 (see figure 43) with brake fluid;
- remove valve protective cap 2 (see figure 46), put on bleeding hose on the valve, unscrew
the valve 1/2-3/4 torque and immerse the hose end into a clean, transparent vessel with brake flu-
id;
- loosen the nut 4 (see figure 43), and when first liquid drops appear, fasten it;
- yank the clutch pedal 25 at the open valve and smoothly release it at the closed valve until
air bubbles stop exiting the hose. If air bubbles with liquid stop exiting, fasten the bleed valve.
Follow that liquid level in the reserve tank is always more than a half and hose end is con-
stantly in the liquid during bleeding, so that no air is sucked by the master cylinder.
The criteria of completed bleeding is force spur increase on the pedal when it moves for L
2
value equal to 35-40 mm after selection of free play.
Quick clutch hydraulic gear bleeding is possible by using external compressed air, for that:
- fill the reserve tank with brake fluid;
- remove valve protective cap 2 (see figure 46), put on bleeding hose on the valve, unscrew
the valve 1/2-3/4 torque and immerse the hose end into a clean, transparent vessel with brake flu-
id;
- put on the hose of the external compressed air to the lid head 2 (see figure 43) of the re-
serve tank 1;
- supplying compressed air with the pressure not exceeding 200-250 kPa (2.0-2.5 kgf/cm
2
)
and wait until air bubbles stop exiting the tube.
4.2.1.7 Maintenance of clutch gear is performed by periodical inspection of gear compo-
nents, cleaning them and checking:
- air tightness of the hydraulic and pneumatic parts;
- liquid level in the reserve tank and fastening screws;
4.2.2 Wabco Air-Over Hydraulic Booster Construction and Operation
Wabco air-over hydraulic booster is installed to the power unit. The clutch is released by
Wabco air-over hydraulic booster.
Air-over hydraulic booster consists of three main parts: pneumatic slave cylinder, servo
system and clutch lining wear indicator.
Air-over hydraulic booster construction is shown in figure 47.