Great Plains 1007NT Operator Manual - Manual (Page 19)

Great Plains Manufacturing, Inc. Preparation and Setup 15
10/06/2010 150-290M
Hydraulic Hose Hookup
Connect hydraulic system to tractor before lifting the drill.
Escaping fluid under pressure can have sufficient pressure to
penetrate the skin. Check all hydraulic lines and fittings before
applying pressure. Fluid escaping from a very small hole can
be almost invisible. Use paper or cardboard, not body parts,
and wear heavy gloves to check for suspected leaks. If injured,
seek immediate medical attention from a physician familiar
with this type of injury.
The hydraulic system of the 1007NT drill has one circuit,
which controls two functions:
• Forward lift with depth-control stop valve.
• Rear lift-assist, which is fully retracted in the field.
Note: Prior to first use, adapt the 1 ⁄
2
in male NPT hose fit-
tings to connectors compatible with the tractor.
Use liquid pipe thread sealant (not tape) on NPT.
A poppet style QD (Quick Disconnect) to
1 ⁄
2
in FNPT
coupler is available as Great Plains part 811-856C.
Refer to Figure 4
To distinguish hoses on the same hydraulic circuit, refer
to plastic hose label. The hose under an extended-cylin-
der symbol feeds a cylinder base end. The hose under a
retracted-cylinder symbol feeds a cylinder rod end.
12. Connect the hydraulic hoses to the tractor remotes.
Re-phasing Cylinders
The lift cylinders may, after a period of time, get out of
time or phase. The effects of this can be seen when not
all cylinders are fully extended at full lift.
To re-phase the cylinders, raise drill completely and hold
tractor hydraulic lever on for a few seconds to give cylin-
ders time to re-phase.
Each time drill is raised out of ground momentarily
reverse hydraulic lever immediately after re-phasing to
allow cylinders to retract about
1 ⁄
2
in (13mm). This helps
in maintaining a level drill.
Note: Having cylinders become gradually out of time is
different than air trapped in the system. Each con-
dition is corrected differently. Perform “Hydraulic
Setup” on page 73 to purge air from the system.
Figure 4
Drill Hydraulic System
31608
1
1
Figure 5
Plastic Hose Label
817-348c
17641