Great Plains PD8070 Operator Manual - Manual (Page 50)

46 PD8070 Table of Contents Index Great Plains Manufacturing, Inc.
401-479M Table of Contents Index 2014-07-23
Row Unit Down Pressure
Row unit springs provide the primary down pressure
necessary for row unit disks to open a seed trench.
The springs allow the row units to float down into
depressions and up over obstructions. Springs also
provide down force on coulters when using optional row
mounted coulters, and provide the primary down force on
seed firmers (optional) and press wheels.
A T-handle sets down pressure individually for each
row unit. This is useful for penetrating hard soil and
planting in tire tracks. For best results adjust tractor tires
so they are not ahead of rows.
Refer to Figure 47
Use only enough down pressure to cut the seed trench
and maintain proper soil-firming over seed. Excessive
row unit down force will lead to premature wear on row
unit components, uneven seed depth and gauge wheel
slippage.
Note: Do not set all rows higher than notch four. Using
high settings across all rows causes uneven
planting. Individual rows may be set higher if
running in tire tracks.
Standard Springs Down Force
First Holes (Closest to Tractor)
38 kg
(85 pounds)
Second Holes
45 kg
(100 pounds)
Third Holes
52 kg
(115 pounds)
Fourth Holes
61 kg
(135 pounds)
Fifth Holes (Closest to Hopper)
70 kg
(155 pounds)
Heavy-duty springs are optional. See page 91 for
ordering information.
Figure 47
30 Series Down Force
25454
Heavy-Duty Spring
Package
Down Force
First Holes (Closest to Tractor)
70 kg
(155 pounds)
Second Holes
79 kg
(175 pounds)
Third Holes
93 kg
(205 pounds)
Fourth Holes
102 kg
(225 pounds)
Fifth Holes (Closest to Hopper)
111 kg
(245 pounds)
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