4000 hydraulic down pressure – Great Plains 4000TC Operator Manual User Manual
Page 29
Great Plains Manufacturing, Inc.
Operating Instructions
25
08/01/2012
586-239M
4000 Hydraulic Down Pressure
Refer to Figure 18
Note: This setup procedure is for tractors with closed-cen-
ter or pressure compensated flow hydraulic systems.
Open center hydraulics not supported.Adjust down
pressure valve as shown on decal
(located on front
of left side of center frame) Refer to Figure 19
Never leave tractor valve centered when unfolded with machine
in motion. Machine damage may occur when wings flex up or
down
This machine is designed for continuos hydraulic flow to the
wing fold cylinders during field operations. It is for use on trac-
tors having CLOSED CENTER hydraulics only. If your tractor
has an OPEN CENTER hydraulics, please consult your dealer
for operating instructions.
39. Adjust the bypass valve by turning knob
clockwise
all the way in and then backing out 1 full turn.
40. On tractor, adjust flow-control valve to low side of flow
rate.
Note: The faster the flow of oil through the system the
greater potential for oil heating, premature wear or
tractor damage.
41. Lock the fold hydraulic lever for continuous downward
oil flow.
42. Adjust pressure reducing valves knob
and
on
implement so the pressure gauges reads 1200 psi
each. Never exceed 1400 psi.
43. While watching pressure gauges, slowly open bypass
valve, knob
until gauges read around 1100 psi.
Pressure might rise and then fall off as knob is opened.
If pressure exceeds 1400 psi during this step, the trac-
tor flow is too high, reduce tractor flow. Lock bypass
valve knob
at 1100 psi.
44. Finally adjust valve knob
to 650-900 psi pressure
setting, never exceeding 1100 psi. Adjust valve knob
(3) to 650-750 psi. pressure setting, never exceeding
1000 psi.
45. In field operation, Lock the fold hydraulic lever for con-
tinuous downward oil flow. If wings are running too
high, increase pressure setting to the appropriate
valve,
and
, to level machine. If center is too high,
decrease pressure setting with knob
on Inside wing
valve.
Figure 18
4000 Down Pressure
848-266C
3
1
2
4
4
Figure 19
4000 Down Pressure Decal
848-266C
1
2
3
1
1
2
2
3
2