Great Plains 3PYPA Operator Manual - Manual (Page 169)

Great Plains Manufacturing, Inc. Table of Contents Index Appendix B - Initial and Option Setup 165
03/20/2012 Table of Contents Index 401-647M
Hydraulic Down Pressure Calibration
(Option)
If your planter is equipped with the optional hydraulic
down pressure system, it needs an initial/seasonal setup.
Equipment Damage Risk:
If your tractor has Open Center hydraulics, do not engage the
down pressure hydraulics. The current hydraulic down pres-
sure option is compatible only with tractors having Closed
Center systems.
Note: The hydraulic down pressure kit is integrated with
the lift assist system. When the down pressure sys-
tem cycles, the planter raises and lowers.
Refer to Figure 166
There are two adjustable valves in the system:
PC Closed Down Pressure Calibration
Tractors with Pressure Compensating Closed Center
Hydraulics (PC Closed)
1. Release locking disk .
2. Close bypass valve for no oil flow by turning knob
on valve clockwise completely.
3. Tighten locking disk . Always operate the planter
with the bypass valve closed.
No further adjustments are made at this time. See
“Hydraulic Down Pressure” on page 60 for field opera-
tions.
Bypass valve:
located near parallel arms
Adjustment valve:
located near hitch
Null4:
Figure 166
Hydraulic Down Pressure Valves
29803
1
2
3
4
1
2
3
1
3