Section E - Hydraulics
Operation Description
Self Level Valve
E - 25 E - 25
9803-9450-2
Self Level Valve
The optional self level valve diverts a small amount of oil to
the Quickhitch tilt ram to give self levelling of the
Quickhitch as the loader arm is raised. A solenoid valve
allows the self level circuit to be switched in or out as
required by the operator.
Loader Arm Raise - Self Levelling
K Fig 21. ( T E-25)
With the Quickhitch tilt spool 9C in neutral and the loader
arm spool 9B selected to ‘raise’, oil from the loader valve 9
enters the head side of the loader arm ram 2. As the ram
extends, flow from the rod side is directed to port ‘A’ on the
self level valve 4. When the self level function is switched
on, solenoid valve 4a is de-energised (closed) so oil
passes through the adjustable orifice 4b and also the fixed
orifice in the flow divider spool 4c. The proportion of the
flow split is determined by the size of the adjustable orifice.
The remainder of the flow passes through the fixed orifice
and out of port ‘B’, returning to the loader valve and back
to tank. The oil passing through the adjustable orifice 4b
lifts check valve 4e, flows out of port ‘D’ and is fed to the
head side of the tilt ram 5. The resistance to movement of
the tilt ram creates enough pressure to open the unloading
spool 4d in the self level valve.
As the tilt ram extends the flow from the rod side enters
port ‘C’ past the open unloading spool 4d, around the flow
divider spool 4c and out of port ‘B’ back to the loader valve
9 and to tank. The purpose of the unloading spool 4d is to
prevent the tilt ram from dumping oil during the self level
cycle.
If the solenoid valve 4a is energised (open), the flow from
the rod side of the lift ram is allowed to pass via port ‘B’ to
the loader valve 9 and back to tank. Thus the self level
circuit does not operate.
Fig 21.
2
5
9
9
4
'A'
B'
'C'
'D'
4b
4c
9
4d
4e
4a
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