Great Plains YP3025A Operator Manual - Manual (Page 70)

66 YP3025A Table of Contents Index Great Plains Manufacturing, Inc.
401-705M Table of Contents Index 02/16/2012
Row Unit Down Pressure
Refer to Figure 66
Row unit down force is created by:
+ cam-adjusted spring force,
+ the weight of the row unit,
- variable force removed by the optional Row-Pro™
pneumatic system.
The ideal amount of down-force causes the side gauge
wheels to compress any loose surface soil, but not press
a trench into subsoil.
To assess down-force, operate the planter for a short dis-
tance on typical ground (with or without seeding), and
stop. Leave the planter lowered (row units in ground).
At several row units, inspect the furrow created by the
opener discs, but prior to furrow closing by the press
wheels.
Note: Be sure to inspect rows both in and out of tractor
tire tracks.
Refer to Figure 67
1.
If the side gauge 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 Down-Force
The the planter has the optional Row-Pro™ system, set
the cam-adjusted system to the maximum force needed
for the present field conditions. The pneumatic cylinders
provide a maximum force reduction of about 60 pounds,
which is only one cam notch at higher settings.
Refer to Figure 68
Row unit springs
provide the primary down pressure
necessary for row unit disks to open a seed trench. The
weight of the row units themselves contributes about
130 pounds (59 kg) of the total force.
The springs allow the row units to float down into depres-
sions and up over obstructions. Springs also provide
down force on coulters when using optional row mounted
coulters, and provide the primary down force on row
cleaners (optional), seed firmers (optional) and press
wheels.
{
Inspect Furrow Here
Null4:
Figure 66
Checking Furrow
29600
Light or no side gauge
wheel tracks Insufficient down-force
Increase down-force
Gauge wheels compress
loose soil only Ideal
No adjustment required
Side gauge wheels
making deep tracks Down-force too high
Reduce down-force
Null4:
Figure 67
Assessing Down-force
1
2
3
1
Null4:
Figure 68
25 Series Row Unit Springs
29600
1