Great Plains 3N-4020 Operator Manual - Manual (Page 88)

84 3N-4010F/3N-4010HDF/3N-4020F Table of Contents Index Great Plains Manufacturing, Inc.
196-359M Table of Contents Index 2013-10-29
20 Series Row-Unit Adjustments
Refer to Figure 126, which depicts a 20 Series row unit fully
populated with all features supported on 3N-4020F drill (ex-
cepting Seed-Lok). From front to back, they are:
1. Dual Down-Pressure Springs & Cam (standard)
See “20 Series Row-Unit Down Pressure” on
page 85. Each row-unit is mounted on the planter
with parallel arms. This parallel-action mounting
allows the row-unit to move up and down while stay-
ing horizontal. A cam
adjusts the force between
100 and 225 pounds.
2. Double Disk Openers (standard)
A pair of canted opener disk blades
open a furrow
and keep it clear for the seed tube. These disks are
adjustable for contact. See “20 Series Row-Unit
Down Pressure” on page 85.
3. Side Depth Gauge Wheels (standard)
These wheels
are the primary control of seeding
depth (set by the T-handle). They also have adjust-
ments for angle and disk contact. See “Side Gauge
Wheel Adjustments” on page 86.
4. Seed Tube (standard)
A seed tube mounted between the disks (not shown)
delivers seed to the trench. It is fed by the seed
meter, and has a seed flap
, shown here cut back
for clearance from the seed firmer. See “20 Series
Seed Firmer Adjustments” on page 88.
5. T-Handle (standard)
This handle
sets the height of the side depth
gauge wheels. See “20 Series Row-Unit Planting
Depth” on page 85.
6. Seed Firmer (optional)
An optional seed firmer (Keeton shown) minimizes
seed bounce and improves soil contact. See “20
Series Seed Firmer Adjustments” on page 88.
7. Press Wheels (standard)
The press wheels close the furrow, gently pressing
the soil over the seed to ensure good seed to soil
contact for even emergence. They have adjustments
for down-pressure, stagger and angles. See “20
Series Press Wheels” on page 89.
Certain Machine Damage:
Do not back up with row-units in the ground. This will cause
severe damage and row-unit plugging.
Figure 126
20 Series Row Unit
28313
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