Great Plains 3N-4020 Operator Manual - Manual (Page 75)

Great Plains Manufacturing, Inc. Table of Contents Index Adjustments 71
2013-10-29 Table of Contents Index 196-359M
10 Series Row Unit Down Pressure
Refer to Figure 102
The ideal amount of down-force causes the press wheels
to compress any loose surface soil, but not press a
trench into subsoil.
To assess down-force, operate the drill for a short dis-
tance on typical ground (with or without seeding), and
stop. Leave the drill lowered (row units in ground).
At several row units, inspect the furrow created by the
opener discs and closed by the press wheels.
Note: Be sure to inspect rows both in and out of tire
tracks.
Refer to Figure 103
1. If the press wheels are leaving no tracks, or light
tracks, increase down-force.
2. If the wheels are compressing trash and loose soil,
and leaving clear tracks right at the top of the sub-
soil, down-force is probably correct and needs no
adjustment.
3. If the wheels are creating a trench into the subsoil,
down-force is too high and needs to be reduced.
Adjusting 10 Series Down Force
The springs allow the row units to float down into depres-
sions and up over obstructions.
On 10 Series row units, the seed trench is primarily
opened by the coulters. Row unit springs provide only
additional assistance needed to make a furrow “V”
shaped and ensure furrow closure by the press wheels.
Often, the rows may be run at the minimum spring set-
ting, other than in tire tracks, which commonly need
some adjustment.
If trench depth is not being achieved across all rows,
adjust the force and/or depth of the coulters before mak-
ing row unit spring adjustments.
If you cannot achieve enough down force, adding a
weight kit may help. See “Dual Weight Kit” on page 120.
Figure 102: 10 Series:
Checking Furrow
26414
{
Inspect Furrow Here
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 103: 10 Series:
Assessing Down-force
1
2
3