SkyTrak 8042 Service Manual - Manual (Page 478)

8.63 Model 8042, 10042, 10054 Legacy Rev. 10/03
Hydraulic System
8.8.28 Outrigger Circuit Description
(10042/10054)
System pressure is applied to the outrigger circuit
through the main control valve to the outrigger valve.
Fluid flow is directed to either side of the outrigger
cylinders by the outrigger valve. The valve is controlled
by the position of the left and right outrigger switches
located on the side console.
a. UP Position (refer to page 8.42)
Pressing the top of the left and right outrigger
switches will raise the outriggers. Two of the
solenoids on the outrigger valve are
energized. The spools are shifted allowing
flow to the rod end of the outrigger cylinders.
Pilot pressure opens the counterbalance valve. The open
counterbalance valve allows return oil from the base end
of the outrigger cylinders to flow back to the outrigger
valve, to the main control valve, to the oil cooler, to the
return filter and then to the reservoir.
If the return filter becomes restricted, hydraulic oil will
bypass the filter when the pressure reaches 25 psi
(1,7 bar).
b. DOWN Position (refer to page 8.44)
Pressing the bottom of the left and right
outrigger switches will lower the outriggers.
The other solenoids on the outrigger valve
are energized. The spools are shifted
allowing flow to the base end of the outrigger cylinders.
Return oil from the rod side of the outrigger cylinders is
directed back through the outrigger valve, to the main
control valve, to the oil cooler, to the return filter and then
to the reservoir.
If the return filter becomes restricted, hydraulic oil will
bypass the filter when the pressure reaches 25 psi
(1,7 bar).
MH3890
MH3900