Great Plains 3S-4000F Operator Manual - Manual (Page 59)

Great Plains Manufacturing, Inc. Table of Contents Index Adjustments 55
2014-06-10 Table of Contents Index 195-394M
For Drills Without Markers
Setting opener down pressure above 1600 psi will raise
drive wheels off the ground when the seed box is empty
causing skips and poor seed metering.
For Drills With Markers
Setting opener down pressure above 2300 psi will raise
drive wheels off the ground when the seed box is empty
causing skips and poor seed metering.
Refer to the chart on page 54 for approximate force at
the openers for a given pressure setting.
1. 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.
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
forward on these tractors can cause overheating of hydraulic
oil and tractor damage. After setting opener down pressure,
always return hydraulic lever to neutral.
Spring Down Pressure-Individual Openers
Refer to Figure 58
For planting in tire tracks, you can increase spring
pressure on individual openers. To increase spring
pressure, tighten flange nut at lower end of opener
spring. Each
1 ⁄
4
inch adjustment adds about 13 pounds
of force at opener disk. Do not tighten nut more than
one inch. After adjusting, lock flange nut in place with
jam nut.
Figure 58
Individual Opener Pressure
Adjustment
15637
Flange Nut
Jam Nut