Great Plains 3S-3000HDF Operator Manual v2 - Manual (Page 56)

52 3S-3000HD Table of Contents Index Great Plains Manufacturing, Inc.
195-068M Table of Contents Index 2014-02-11
Setting Hydraulic Down-Pressure
1. Lower openers to the ground. Lock hydraulic lever
forward for constant hydraulic flow.
You must lock hydraulic lever forward. See “Opener Opera-
tion” on page 31.
Refer to Figure 48
2.
Release lock disk . Turn knob on pressure-con-
trol valve while watching pressure gauge, turn knob
until gauge shows desired pressure. Turn clockwise
to increase pressure. Turn counterclockwise to
decrease pressure.
There is one pressure-control valve for openers on
the center section and one for openers on the wing
sections of the drill.
Refer to the chart on page 51 for approximate force
at the openers for a given pressure setting. As a gen-
eral starting point, set hydraulic down pressure to
1200 psi. For most field conditions, adjust down
pressure between 1200 and 1800 psi.
Population Risk:
Do not operate at pressures so high that the gauge wheels
loose traction, or are off the ground, resulting in skips and
poor seed metering.
3. Once pressure is set, lock knob with lock disk. If
using a non-active hydraulic system to run drill,
unlock the hydraulic remote lever and return it to
neutral.
Machine Damage Risk:
Open-center tractors and tractors with fixed-displacement
pumps are not designed to provide a continuous supply of
pressurized oil to remote valves. Locking hydraulic lever for-
ward on these tractors can cause overheating of hydraulic oil
and tractor damage. After setting opener down pressure,
always return hydraulic lever to neutral.
FigureSpacer
Figure 48
Down-Pressure Valves
26477
1
2
1 2