Great Plains P15061 Serial No 12682 - Manual (Page 35)

35 Solo
Operating Instructions
5. Servicing and Maintenance
5.9.4 Roll Hydraulics
Tampering with a pressurised
hydraulic system is extremely
dangerous.
Pressure may be retained in the
roll circuit between the valve and
the cylinders. Although it shouldn’t
be necessary to remove the fittings
between the valve and the
cylinders, the de-pressurisation
procedure should be followed
before doing so.
De-pressurisation Procedure
for Roll Hydraulics
To de-pressurise the circuit, identify and
adjust the following valves on the roll valve
block.
All valves can be identified by stamped codes
adjacent to each valve.
1. Set tractor hydraulics to neutral,
machine lowered and unfolded.
2. Adjust Over Centre valve (1) fully
clockwise.
3. Adjust Over Centre valve (2) fully
clockwise.
4. Set main system to float, or allow oil
pressure to be released in both
directions.
The manifold may need de-
pressurising after being subjected to
high oil flow.
Roll Hydraulics Setting
Procedure - Factory settings
The following table outlines the re-setting of
the roll hydraulics back to factory settings.
Each number below corresponds to the
relevant valve on the hydraulic block located
near the roll section of the machine.
Valve # Function Setting Procedure
1 Over Centre Valve
for locking wings
down in work Adjust the valve all the way
out (anti-clockwise) then a
half turn in (clockwise).
2 Over Centre Valve
for holding wings
safely during
unfolding Adjust the valve all the way
anti-clockwise then check
by unfolding the wings to a
45° angle and putting the
hydraulics into float. The
wings will now be locked.
Slowly turn the valve
clockwise until the wings
start to lower. At this point
stop the wings lowering by
slowly turning the valve anti-
clockwise. When the wings
have stopped lowering turn
the valve one full turn anti-
clockwise and lock it off.
3 Relief Valve -
Unfolding Set to 80 bar
4 Relief Valve -
Folding Set to 150 bar