Great Plains 3P4025AH Operator Manual - Manual (Page 92)

88 3P4025AH Table of Contents Index Great Plains Manufacturing, Inc.
411-099M Table of Contents Index 2014-07-29
Wing Flex Cylinder Bleeding
Refer to Figure 96 and Figure 97
1.
Consult the appropriate flex circuit hydraulic
diagram:
“Wing Down Flex Hydraulics (Option)” on
page 110, or “Wing Down Pressure Hydraulics
(Option)” on page 111 (partially repeated here for
reference).
2. Check that tractor hydraulic reservoir is full.
Set hydraulics for low flow rate.
3. Set circuit to Retract and retract cylinders until they
stop.
4. Set circuit to neutral.
5. Loosen JIC fitting at right cylinder, base end :
6. Set circuit to Extend until fluid appears.
7. Neutralize circuit and secure JIC fitting.
8. Set circuit to Extend until rods extend to stop.
9. Neutralize circuit and loosen JIC fitting at left
cylinder, rod end
:
10. Set circuit to Retract until fluid appears.
11. Neutralize circuit and secure JIC fitting.
12. Extend and retract circuit several times.
Lift-Assist (Option) Cylinder Bleeding
If the lift-assist operates unevenly from side to side, or
operates unsmoothly, there may be air in the system.
1. Lower the planter. Set the tractor lift circuit to Float to
relieve pressure.
2. Disconnect both lift cylinders at their rod ends. Use
the tractor lift circuit to fully retract the rods. Set the
circuit to Neutral to hold at retract.
3. Swing the cylinders up out of the parallel arm
structures and support them, with the rod ends lower
than the base ends.
4. Slightly loosen (“crack”) a JIC or NPT connection
at each cylinder base end. Slowly Extend to supply
oil from the tractor lift circuit. As oil appears at each
cracked fitting, set the circuit to Neutral and tighten
the fitting.
5. Fully extend both cylinders. Set circuit to Neutral.
Raise the supports so that the rod end are higher
than the base ends.
6. Slightly loosen (“crack”) a JIC or NPT connection
at each cylinder rod end. Slowly Retract to supply oil
from the tractor lift circuit. As oil appears at each
cracked fitting, set the circuit to Neutral and tighten
the fitting.
7. Reconnect both cylinder rod ends.
Figure 96
Wing Down Pressure Cylinders
36128
L
R
3
4
Figure 97
Wing Down Flex Cylinders
36124
L
R
4
3
3
4
Figure 98
Lift-Assist Cylinder Bleed
36127
L
R
5
6
5
6