Great Plains 3N-4020 Operator Manual User Manual
Page 66
62
3N-4010F/3N-4010HDF/3N-4020F
Great Plains Manufacturing, Inc.
196-359M
2013-10-29
Crushing Hazard:
Make all down-stop adjustments with circuit in neutral and
drill raised (actuator plunger not in contact with down-stop).
Loosening the down-stop with circuit active and drill lowered
results in rapid lowering of the frame.
Height Mis-setting Risk:
Make sure the drill is level and the lift system bled and
re-phased before adjusting the tool bar height. If the center
section does not consistently stop at the set height, or the
wings do not run at the same height as the center, the lift sys-
tem may have air or be out of phase (above), or the wings may
not be level. See “Frame Alignment and Level” on page 101.
Refer to Figure 88
The lift system includes an adjustable stop valve
to fix
the height of the opener frame when the drill is lowered.
To adjust the stop height:
1.
Move to smooth level ground representative of field
conditions.
2.
Lower the drill and measure the present tool bar
height. If the drill cannot be fully lowered due to row
unit spring settings, temporarily move the cams to a
lower setting, or out of notch entirely.
3.
Raise the drill.
4.
Loosen the knob
on the stop
.
5.
Adjust the stop
position on the tube
. Adjust up
(to raise) or down (to lower). Adjust by half the last
difference. Secure the stop with the knob bolt
.
6.
Lower the drill and measure the tool bar height. If the
error is more than about
1
⁄
8
in (3mm), repeat the
adjustment process from step 3.
7.
Raise and lower several times and confirm that the
drill stops consistently at the new height.
Note: It is important that all tires remain in ground contact
to maintain front to rear levelness. Setting the depth
control too deep combined with high opener spring
force can cause the drill to tip forward when plant-
ing, which may cause plugging.
Running with the front tires floating or skimming on
the ground will cause uneven coulter depth and
may cause uneven seed depth.
Figure 88: UMC/NC:
Opener Depth Stop
20274
2
3
1
4
5
1
2
3
3
4
2