Great Plains 3N-4020 Operator Manual - Manual (Page 80)

76 3N-4010F/3N-4010HDF/3N-4020F Table of Contents Index Great Plains Manufacturing, Inc.
196-359M Table of Contents Index 2013-10-29
Unit-Mounted Coulter Adjustments
Unit-mounted coulters (UMC) are an optional alternative
to frame-mounted coulters. Only one type of coulter may
be installed. See page 122 for ordering information.
Note: Unit-Mount Coulters are not factory-installed.
Check alignment and depth prior to first use.
10HD Coulter Depth Adjustment
Check frame height before making any UMC adjust-
ments. See “Frame Height without Frame-Mounted
Coulters” on page 61.
The ideal operating depth for unit-mounted coulters is
1 ⁄
4
in above opener depth. Although they may have origi-
nally been set to this depth, coulter (and opener) blades
wear with time, and may need adjusting.
Adjusting the coulter depth is accomplished by re-mount-
ing the coulter blade in one of the six mounting holes
arranged in a staggered pattern in the coulter bracket.
Refer to Figure 112 and Figure 113
Raise drill and install cylinder locks before working on
coulters. Row unit may be fully lowered or locked up. Do
not attempt to move blade when the current or new posi-
tion causes it to contact the ground during the adjust-
ment. Be careful around the front end of row units.
Coulter blades may be sharp.
To adjust coulter depth:
1. Determine the present opener and coulter depths.
2. Note which bracket hole the coulter is presently
using.
3. Determine which new hole will position the coulter
closer to the
1 ⁄
4
in-above depth. See the table below.
4. Remove the 5 ⁄
8
-11 x 4in bolt, lock washer and nut (
in Figure 112).
5. Move the blade to the new position. Insert the bolt,
and tighten on the lock washer and nut.
If a worn coulter cannot be adjusted to satisfactory oper-
ating depth, replace the coulter blade.
Hole
No.
Depth of (new) coulter blade relative
to (new) opener blades
1in above
5 ⁄
8
in above
1 ⁄
4
in above
0 (factory standard hole)
3 ⁄
8
in below
3 ⁄
4
in below
Figure 112: 10HD Series:
10HD Series Unit-Mounted Coulter
22817
7
Figure 113: 10HD Series:
Coulter Blade Mounting Holes
23288
1
2
5
4
3
6
7
2
3
5
1
4
6