Frame-mounted coulter force – Great Plains 3N4010HDA Operator Manual User Manual
Page 41
Great Plains Manufacturing, Inc.
Adjustments
37
2013-09-24
196-444M
Frame-Mounted Coulter Force
Coulter springs are set to 400 lbs (181 kg). In normal
operation at target running depth, the spring is at full
extension or only slightly compressed. It compresses
briefly as obstructions and denser soil are encountered.
• 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 spring setting
may be higher than needed. You can extend blade life
by reducing the force at which the blades ride up over
obstructions.
To adjust the coulter spring:
Refer to Figure 33
1.
Raise the drill and install transport locks. See “Rais-
ing” on page 23.
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 (24.8cm), or
longer than 10
1
⁄
4
in (26cm), 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 wing frames off the ground (at
the gauge wheels), resulting in uneven coulter
depth and/or uneven seed depth. If high forces are
required, frame weights are probably required.
Do use spring lengths shorter than 9.75 in (24.8 cm). It may
contribute to premature parts failure which will not be cov-
ered by warranty.
Figure 33
Frame-Mounted Coulter Spring
27139
Spring Length
Force at Blade
10.25 in (26.0 cm)
300 lbs (136 kg)
10.00 in (25.4 cm)
400 lbs (181 kg)
9.75 in (24.8 cm)
525 lbs (238 kg)
1
1
2
3