Multiva Optima T Series, Руководство по эксплуатации и обслуживанию

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3.3. Adjusting hydraulic hoses
After hitching the harrow to the tractor, adjust the hydraulic hoses between the hose rack and tractor to
a suitable length. The length of the hoses can be adjusted by loosening the hose rack lock (point 1 in
the illustration, x 3). Extra hose is left looped in the rack. Tighten the bolts after making the adjustment.
The length of the hoses is correct when the hoses do not become in contact with the tractor's pulling
arms during turning. The length of the hoses is too short if they tense up and disconnect from the
tractor's hydraulic connector during turning. The smallest allowed diameter for a hose loop is 200 mm.
If the diameter is too small, the loop must be opened and the hoses placed on the rack without looping.
If the loop is too small, there is a danger of breaking the hoses. Turn off the tractor and release the
pressure from the hydraulics before handling the hydraulic hoses
3.4. Side section and front levelling board hydraulics selector valve, Optima T500 - T700
In models Optima T500 - T700 , the levelling board hydraulics and the side section hydraulics function
alternately using the same tractor valve, depending on the height adjustment of the machine. When
the harrow is raised up for transport, the selector valve in the frame of the machine directs the hydraulic
pressure to the lifting cylinders of the side sections. When the machine is in work position, the valve
directs the pressure to the levelling board cylinders. The valve operates automatically when the height
of the machine is adjusted between the work and transport positions. The selector valves are located in
front of the axles, in the centre section of the harrow and they are actuated from the axles through the
actuator arm.
Actuator arm of
the selector
valve
Selector valve