Great Plains 3N-4025P Operator Manual - Manual (Page 32)

3N-4010P, 3N-4015P, 3N-4020P and
3N-4025P
196-286M 4/23/2010
30
Adjustments
No-Till Seeding
To get full performance from your no-till drill, you
need a good understanding of coulter, opener
and press wheel operation.
Coulters
A no-till coulter is mounted directly ahead of each
opener. The coulters cut through heavy trash and
till a small strip so the openers can penetrate the
soil easily. To maintain even seeding depth, the
coulters must cut below the openers.
The coulters for 10 and 20 series drills are mount-
ed directly on the box frame. Consequently, the
cutting depth of all coulters changes as the drill is
lifted and lowered.
The coulters for 15 and 25 series drills are either
frame or opener mounted.
The cutting depth of the coulters is controlled by
an adjustable hydraulic depth stop. Coulters that
run directly in tire tracks can be lowered individu-
ally. Refer to “Coulter Adjustments,” page 31, for
information on how to make these adjustments.
Openers
Each opener is mounted on the drill with parallel
arms. This parallel-action mounting allows the
opener to move up and down while staying in-line
with a coulter. Opener double disks widen the
coulter groove, making a seed bed. A seed tube
mounted between the disks delivers seed to the
trench.The down force needed to cut and widen
the coulter groove is supplied by two springs nest-
ed in the parallel linkage. Adjusting these springs
changes opener down-force. Refer to “Opener
Down Pressure,” page 34, for information on how
to make this adjustment.
The HD 10 series openers do not utilize a frame
mounted coulter to open the seed trench. Down
force to cut and widen the seed trench is supplied
by four springs nested in the parallel arms. Ad-
justing these springs changes the ability to
penetrate trash and cut a seed trench. Refer to
“Opener Down Pressure,” page 33, for informa-
tion on how to make this adjustment.
Press Wheels
Attached to the rear of each opener is one of
several press-wheel options. The press
wheels provide two important functions.
First, the press wheels close the furrow, gently
pressing the soil over the seed. To provide
consistent seed firming, the press wheels are
free to move downward from their normal op-
erating position. This system maintains
pressing action even if the opener arm is lifted
when the disks encounter obstructions.