Coulter down pressure, Available coulter force per row, Coulter spring length – Great Plains 3P1006NT Operator Manual User Manual
Page 37
Great Plains Manufacturing, Inc.
Adjustments
33
2011-12-20
151-144M
Coulter Down Pressure
The maximum down force at the coulters depends on:
• empty drill weight (page 26),
• extra weights added (page 34),
• down-force consumed by the opener discs (this can
range from 50-150 pounds), and;
• the current material loading (which declines to zero
during planting).
3P1006NT configurations typically are too light to reach
the factory down-force of 400 lbs at all rows. The table at
right shows typical forces available. Do not increase
coulter spring forces drill-wide unless weight is available.
Coulter Spring Length
Coulter springs are preset at 10 in. (25.4 cm), giving
coulters an initial operating force of 400 pounds before
the spring compresses. This setting is adequate for
many difficult no-till conditions.
In normal operation at target running depth, springs are
at full extension or only slightly compressed. They
compress briefly at obstructions and in denser soil.
• In heavy no-till conditions, you may observe the
springs in compression most of the time. This means
that the blades are not reaching the desired coulter
depth. If adequate drill weight is available, you can
increase the spring down-force to compensate.
• In light but rocky conditions, the factory setting may be
higher than needed. Extend blade life by reducing the
force at which the blades ride up over obstructions.
To adjust the coulter spring:
Refer to Figure 22
1.
Raise the drill and install transport locks. See “Drill
Lift/Lower (s/n A1059W+)” on page 20.
2.
Determine the new spring length
desired. See the
table at right.
3.
Measure the current length of the spring(s) to be
changed. If already shorter than 9
3
⁄
4
in., or longer
than 10
1
⁄
4
in., do not further adjust them.
4.
Loosen the jam nut
.
5.
Rotate the adjuster nut
until the spring is at the
new length. Tighten the jam nut.
Note: If all springs are continuously in compression, the
coulters can lift the drill off the ground (at the
ground drive wheels), resulting in low seeding rates
and uneven seed depth. If high forces are required,
frame weights are probably required.
Standard Drill
174 lbs (79 kg) 252 lbs (114 kg)
Drill w/Fertilizer
195 lbs (89 kg) 273 lbs (124 kg)
Drill w/Native Grass 193 lbs (87 kg) 271 lbs (123 kg)
Drill w/Small Seed
178 lbs (81 kg) 256 lbs (116 kg)
200 lbs (91 kg) 278 lbs (126 kg)
NG & Small Seed
213 lbs (97 kg) 291 lbs (132 kg)
32800B
Drill
Configuration
Empty
Drill
Drill with Full
Weight Kit
Fert. & Small Seed
Available Coulter Force Per Row
Machine Damage Risk:
Resetting coulter-spring length shorter than 9
3
⁄
4
in. may cause
premature failure of parts, and voids the warranty. No
3P1006NT configurations have enough weight to compress all
springs shorter than 9
3
⁄
4
in.
Figure 22
Coulter Spring
27139
Spring Length
Force at Blade
10
1
⁄
2
in. (26.7 cm)
175 lbs. (79 kg)
10
1
⁄
4
in. (26.0 cm)
300 lbs. (136 kg)
10 in. (25.4 cm)
400 lbs. (181 kg)
9
3
⁄
4
in. (24.8 cm)
525 lbs. (238 kg)
1
2
3
1
1
2
3