Great Plains 1520P Operator Manual - Manual (Page 29)

5/6/2010 118-732M
27 Adjustments
20 Series Openers
Opener Down Pressure
Refer to Figure 18
Opener springs provide the down pressure nec-
essary for opener disks to open a seed trench.
The springs allow the openers to float down into
depressions and up over obstructions.
You can adjust down pressure individually for
each opener. This is useful for penetrating hard
soil and planting in tire tracks.
Use enough down pressure to cut the seed trench
and maintain proper soil-firming over seed. Ex-
cessive opener down force will lead to premature
wear on opener components.
Refer to Figure 19
To adjust down pressure, use adjustment tool
stored under walkboard. Position tool in hole on
spring mounting plates, and pull down. Move the
adjustment cam to the new setting.
Refer to Figure 20
Minimum and maximum settings are indicated by
position of adjustment cam.
Figure 18
20 Series Opener with Meter
Opener spring
Disk
18273
Adjustment
tool
Figure 19
Adjustment Tool
18409
Figure 20
Adjustment Cam Settings
12104
Minimum setting Maximum setting