Great Plains 2000 Operator Manual - Manual (Page 19)

16
Section 3 Adjustments
12, 15 and 20 Foot Series Three-Point Drills 118-389M-A 2012-03-27
Great Plains Mfg., Inc.
Frame Height
Drill operating height directly affects the working range of
the drill openers. Initially adjust frame height as explained
under Leveling Drill, Preparation and Setup, page 9. You
can make further adjustments to compensate for field
conditions.
When adjusting the gauge-wheel turnbuckles, remember:
• Lengthening turnbuckles raises drill and allows less
opener down float.
• Shortening turnbuckles lowers drill and allows less
opener up float.
After adjusting gauge-wheel turnbuckles, level drill with
top three-point link.
NOTE: Lowering the drill increases the risk of opener
damage on rocks or obstructions.
Seeding Rate
Calibrating the seeding rate requires four steps: shifting
the gearbox, setting the seed-rate handle, positioning the
seed-cup doors, and checking the seeding rate.
Refer to the seed-rate charts starting on page 18. These
charts list the proper drive types and seed-rate handle set-
tings for various seeds and seeding rates.
The seed-rate charts are based on cleaned, untreated
seed of average size and test weight. The rates are based
on 9.5L x 15 rib implement gauge-wheel tires on the 12-
and 15-foot drills and 11L x 15 rib implement tires on the
20-foot drill. Many factors affect seeding rates including
foreign material, seed treatment, seed size, field condi-
tions, tire pressure and test weight. You likely will need to
make minor adjustments. Set and check the seeding rate
using the procedures below, then re-adjust the rate as
necessary.
Before setting the seeding rate, rotate the drive gauge
wheels. Check that seed cups and drive are working prop-
erly and free from foreign material.
1. Shift gearbox drive type.
Refer to the seed-rate charts for the correct drive
type–1, 2, 3 or 4–for your desired seeding rate. Move
the selector handle on the gearbox until the correct
number appears in the handle window as shown in
Figure 3-8. Rotate the tires a few turn to make sure the
gearbox has engaged.
NOTE: If your drill has more than one gearbox, make sure
both are shifted to the same drive type.
Figure 3-8
Seed Rate Gearbox
2. Set Seed-Rate Handle
Position handle for each drill box to setting indicated
on chart. One handle is shown in Figure 3-9. To ad-
just, loosen the wing nut under the handle. Slide han-
dle past desired setting, then move handle back until
indicator lines up with correct setting. Retighten wing
nut.
Figure 3-9
Seed-Rate Handle
Gearbox Ratios:
Drive Type 2 is 2.06 Times Faster Than 1
Drive Type 3 is 3.08 Times Faster Than 1
Drive Type 4 is 5.03 Times Faster Than 1
12095
12927