Great Plains NTA3007HD Operator Manual - Manual (Page 91)

Adjustments 87
04/04/2011 166-207M
Control Valve Overview
Refer to Figure 93
There is one flow control, and three pressure controls.
Each pressure control has a gauge. All of the controls
have an adjustment knob
and a locking disk to fix
the chosen setting.
These controls must be set and adjusted prior to first
field use of the drill. They require re-adjustment when
there are significant changes in field conditions.
1. Unfold (page 26) and lower (page 32) drill. Put trac-
tor in Park and set parking brake.
2. Lock hydraulic lever forward during field operation for
constant hydraulic flow to openers.
John Deere tractors with Sound-Gard ® Body:
Use lever lock clip, John Deere part number R52667,
to lock lever forward. See your tractor dealer for clip
purchase and installation.
John Deere 7000 Series tractors: Rotate valve
detent selector to motor position to lock lever in for-
ward position.
John Deere 8000 Series tractors: Set timer to con-
tinuous. Push lever forward until detent clicks.
Case-IH Magnum tractors: Lock lever forward in
detent position. You may need to turn up detent pres-
sure to its maximum setting. Do not tie hydraulic
lever past detent position with a strap. See your trac-
tor dealer for hydraulic-system details.
Other tractors: Lock lever forward in detent position.
You may need to turn up detent pressure to maxi-
mum or use a mechanical detent holder to hold lever
forward. See your tractor dealer for proper means of
providing constant flow to openers
3. At bypass valve , release locking disk and close
bypass valve for no oil flow by turning knob clockwise
completely.
Bypass valve (normally closed),
adjusted on tractors with “LS closed” hydraulics
, Center section down-pressure,
sets the force applied to all center section rows,
and may be set higher than wings
, Wing down-pressure,
sets the force applied to all wing rows, and may
be set lower than the center section.
, Transfer of weight from center to wings,
sets the weight available to the wings. At higher
wing down-pressures, it is possible for the rows to
lift the wings, unless weight is transferred.
Null4:
Figure 93
Down-Pressure Valve Block
29422
W
C
T
B
k
r
w
c
t
Crushing and High Pressure Fluid Hazards:
This adjustment requires working near the unfolded and low-
ered drill with the hydraulic system active. Assign two people
to this task, one in the tractor cab, ready to shut the tractor
down on hand signal from adjuster or any unplanned event.
k r
B
C c
W w
T t
B