Great Plains 3N-4020 Operator Manual - Manual (Page 89)

Great Plains Manufacturing, Inc. Table of Contents Index Adjustments 85
2013-10-29 Table of Contents Index 196-359M
20 Series Row-Unit Down Pressure
Refer to Figure 127
An adjuster cam sets row unit spring down pressure
individually for each row unit. This is useful for penetrat-
ing hard soil and planting in tire tracks.
To adjust down pressure, use a tool to lift and rotate the
adjustment cam.
1. Raise the drill. Although this adjustment can be
made with the drill lowered, the springs will be in ten-
sion, and will require more effort. The extra force
required may also damage tools.
2. Put tractor in Park and shut it off.
3. Position tool under upper spring link, and pull it back
and up.
4. Move the adjustment cam to the new setting on the
spring adjust bar
.
Note: Do not set all rows higher than notch two. Using
high settings across all rows causes uneven plant-
ing. Individual rows may be set higher if running in
tire tracks.
20 Series Row-Unit Planting Depth
Refer to Figure 129
Side depth wheels outside the row-unit disks con-
trol row-unit planting depth. The position of an adjustable
stop, using the T-handle
, determines planting depth.
Set planting depth by adjusting handle . To adjust, first
raise row-units slightly, then lift and slide handle on top of
row-units. Adjust all handles to the same setting.
For shallower planting, slide handle forward toward
planter.
For deeper planting, slide handle back away from
planter.
Cam Notch Pounds
zero (out of notch) Maintenance Only
one 100
two 165
three 225
tip Do Not Use
Figure 127: 20 Series:
Row Unit Minimum & Maximum
12104
8
3
2
2
1
8
1
2
3
Light or no press wheel
tracks Insufficient down-force
Increase down-force
Press wheel(s) compress
loose soil only Ideal
No adjustment required
Press wheel(s)
making deep tracks Down-force too high
Reduce down-force
Figure 128: 20 Series:
Assessing Down-force
1
2
3
8
Figure 129: 20 Series:
Side Depth Gauge Wheels
27387
1
2
3
1 2
3
3