Great Plains NTA3007 Operator Manual - Manual (Page 137)

Great Plains Manufacturing, Inc. Table of Contents Index Maintenance and Lubrication 133
2012-07-02 Table of Contents Index 166-371M
Marker Maintenance
Review See “Marker Safety Information” on page 73
before performing maintenance on markers.
See also:
“Marker Operation (Option)” on page 73,
“Marker Adjustments” on page 115, and
“Initial Marker Setup” on page 183.
Marker Shear Bolt
The marker arm is attached to marker body with a shear
bolt
, which is intended to fail if the marker strikes an
obstruction, allowing the marker to swing back around a
second bolt
.
If the shear bolt breaks, replace it with an equivalent
7 ⁄
16
-14
×2in Grade 5 bolt (Great Plains part 802-589C).
If that size is not immediately available in your local
market, temporarily substitute an M10
×1.5 Class 8.8
metric bolt and nut.
If your conditions result in frequent shears, the marker
shear base has storage holes for spare bolts.
Note: Replacing the bolt with a lower grade, or smaller
size, can result in nuisance shears.
Machine Damage Risk:
Using a bolt with a higher grade can result in marker damage.
Marker Hydraulic Bleeding
1.
Review warnings, bleeding notes and system
information on page 128.
Refer to Figure 132
2.
With markers unfolded in field position, crack
hydraulic-hose JIC fittings at base
and rod
ends of each marker cylinder.
3. With tractor at idle speed, actuate tractor hydraulic
valve forward until oil appears at a fitting. When oil
begins to seep out around a fitting, tighten that
fitting. Reverse the tractor hydraulic valve until oil
appears at opposite hose fitting. Tighten that fitting.
4. If you have dual markers, actuate tractor hydraulic
valve forward again until oil seeps out around a fitting
on the other marker cylinder. Tighten that fitting.
Reverse tractor hydraulic valve until oil seeps out
around remaining hose fitting and tighten it.
5. Fold and unfold markers slowly to work out all air.
Note: Use caution when folding and unfolding markers for
the first time. Check for hose pinching and kinking.
Figure 131
Marker Shear Bolt
23204
Crushing and Overhead Sharp Object Hazards:
Never allow anyone near the drill when folding or unfolding
markers. You may be injured if hit by a folding or unfolding
marker. Markers may fall quickly and unexpectedly if the
hydraulics fail.
1
2
1
2
Figure 132
Marker Bleed Points
29489
1
2
1
2
1
2