Hydraulic system safety valves: trimming
There are two safety valves for preventing overpressure: one on the steering circuit and
one on the mast operating circuit. The first is located on the hydraulic steering
(fig. 1)
and the second on the control valve
(fig. 2)
. These valves are set to the correct pressure
in the factory, but their trim should be checked regularly and adjusted accordingly.
The trimming should be carried out by personnel with a good knowledge of hydraulics
and suitable tools. The pressures should never exceed those given in the section
TECHNICAL SPECIFICATIONS
in this Operator’s and Safety Manual.
Hydraulic steering valve
- Remove the plug
(fig. 1) (a)
.
- To increase the hydraulic pressure turn the interior screw clockwise using
a screwdriver. To reduce the pressure, turn the interior screw in the opposite
direction.
Control valve
- Remove the seal.
- Remove the plastic cover.
- Unscrew the metal cap
(fig. 2) (b)
and loosen the locknut.
- To increase the hydraulic pressure turn the screw clockwise using an allen key. To
reduce the pressure, turn the interior screw in the opposite direction.
Hydrostatic transmission filter: Replacing
The hydrostatic circuit has a cartridge filter
(fig. 3)
which should be replaced regularly
(See
MAINTENANCE CHART
).
- Undo the cartridge filter by turning it to the left.
- Clean the base of the filter and oil the seal of the new filter element.
- Screw on the new filter element and tighten by hand, without using mechanical
means.
Check whether the filter needs replacing (vacuometer).
The filter support has a filter clogged indicator
(fig. 4)
. When the engine is running the
needle should lie in the green zone, or at a maximum, in the yellow zone. If the needle
approaches or lies in the red zone, replace the cartridge filter as soon as possible.
WARNING
Take care to correctly tighten the filter element otherwise the circuit may suction
air from the outside, causing faults in the transmission.
(fig. 3)
(fig. 1)
a
(fig. 2)
b
(fig. 4)
Periodic
Maintenance
Operations
C 400 H / C 400 HI / C 400 H x4 / C 400 HI x4
C 500 H / C 500 HI / C 500 H x4 / C 500 HI x4
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