Great Plains 4000TC Operator Manual - Manual (Page 28)

24 1200-4000TC Table of Contents Index Great Plains Manufacturing, Inc.
586-239M Table of Contents Index 08/01/2012
Bypass Valve Adjustments
1800-3000 Hydraulic Down Pressure
Refer to Figure 16
Note: Note: This setup procedure is for tractors with closed-
center or pressure compensated flow hydraulic sys-
tems. 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 17.
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 tractors
having CLOSED CENTER hydraulics only. If your tractor has an
OPEN CENTER hydraulics, please consult your dealer for oper-
ating instructions.
32. Adjust the bypass/pressure reducing valve by turning
knob , clockwise all the way in and then backing out
1 full turn.
33. On tractor, adjust flow-control valve to low side of flow
rate.
Note: The faster the flow of oil through the system the great-
er potential for oil heating, premature wear or tractor
damage.
34. Lock the fold hydraulic lever for continuous downward
oil flow.
35. Adjust bypass/pressure reducing valve knob on
implement so the pressure gauge reads 1200 psi.
Never exceed 1400 psi.
36. While watching pressure gauge, slowly open valve
knob until gauge reads 1100 psi. Pressure might
rise and then fall off as knob is opened. If pressure
exceeds 1400 psi during this step, the tractor flow is
too high, reduce tractor flow. Lock valve knob
at
1100 psi.
37. Finally adjust valve to the desired wing down pres-
sure setting of 300 to 400 psi. Never exceed 700 psi.
38. In field operation, Lock the fold hydraulic lever for con-
tinuous downward oil flow. If wings are running too
high, increase pressure setting, knob
, to level
machine. If center is too high, decrease pressure set-
ting with knob
on valve.Never leave tractor valve
centered when unfolded with machine in motion.
Machine damage may occur when wings flex up or
down.
Figure 16
1800-3000 Down Pressure
41068
2
1
3
3
Figure 17
1800-3000 Down Pressure Decal
848-265C
1
2
1
1
2
2
2