Great Plains NTA2007HD Operator Manual - Manual (Page 94)

90 Great Plains Manufacturing, Inc. Contents Index NTA607/2007HD
166-283M Contents Index 04/04/2011
Row Unit Spring Adjustment
Row unit springs normally require no adjustment. The
factory setting for the row unit springs is:
In some unusual conditions, rows in tire tracks may need
to be set heavier.
1. Make adjustments with the wings unfolded and the
rows lifted off the ground, so that the springs are at
full extension.
2. Loosen the jam nut . Rotate the adjuster nut .
Shorten spring to increase down-force; lengthen
spring to reduce down-force.
For each turn of the adjuster nut, the down force at
the opener disk changes by approximately:
1.7 kg/turn (3.7 lbs/turn)
3. Re-tighten jam nut after setting force.
Disk Blade Adjustments
Opener disk angle and stagger is not adjustable, but
disk-to-disk spacing is, and may need attention as disks
experience normal wear. Spacers will need to be reset
when blades are replaced.
Refer to Figure 76
The ideal spacing causes the blades to be in contact for
about 2.5cm (1 inch). If you insert two pieces of paper
between the blades, the gap between them should be
0 to 4.4cm (0 to 1.75in).
If the contact region is significantly larger or smaller (or
there is no contact at all), it needs to be adjusted by mov-
ing one or more spacer washers. If the contact region
varies with blade rotation, one or both blades is likely
bent and in need of replacement.
Null4:
Spring length 32.4 cm (12
3 ⁄
4
in)
Assembly length 56.2 cm (22
1 ⁄
8
in)
Null4:
Null4:
Machine Damage Risk:
Do not use spring lengths shorter than 29.8 cm (11
3 ⁄
4
in).
It may contribute to premature parts failure not covered by
warranty.
Figure 75
Row Unit Spring
29427
1
2
3 4
1
2
3 4
Null4:
Figure 76
Checking Disk Contact
26395