Great Plains 3S-5000HDF Operator Manual - Manual (Page 34)

30 3S-5000/F/HD/HDF Table of Contents Index Great Plains Manufacturing, Inc.
195-325M Table of Contents Index 2012-08-14
Priority Flow Hydraulic Systems
On some tractors with load-sensing hydraulics, circuit #1
is capable of taking nearly 100 percent of available
hydraulic flow. Operating the openers or markers on
circuit #1 will starve the other circuit, making one function
inoperable.
To operate markers and constant opener down pressure
at the same time, connect the openers to circuit #2 and
the markers to circuit #3.
Non-Active Hydraulic System
To run drill with open center hydraulics or
fixed-displacement hydraulic pumps requires a Great
Plains kit, part number 194-143A. After installing the kit,
refer to the following instructions for opener operation.
1. Lower opener frames by pushing forward on tractor
hydraulic lever. Lock lever temporarily in this position
while adjusting opener down pressure.
Refer to Figure 22
2. With tractor hydraulic lever locked forward, set down
pressure with adjustment knob. Watch pressure
gauge and dial in desired pressure on openers.
There is one pressure-control valve for openers on
center section and one for openers on wing sections
of drill.
Note: Rotate knob clockwise to increase pressure and
counterclockwise to decrease pressure.
3. Once pressure is set, lock each knob with lock disk.
4. After opener down pressure is set, return tractor
hydraulic lever to neutral. This locks in the selected
pressure, and opener frames will remain fixed in this
position.
Tractor Damage Risk:
Open-center tractors and tractors with fixed-displacement
pumps are not designed to provide a continuous supply of
pressurized oil to remote valves. Locking hydraulic lever
forward on these tractors can cause overheating of hydraulic
oil and tractor damage. After setting opener down pressure,
always return hydraulic lever to neutral.
Note: On some tractors with very positive remote
hydraulic checks, a slight increase in the reading
on the pressure gauges may occur after tractor
remote lever is returned to neutral. This is caused
by back pressure on opener cylinders and should
be ignored. The net operating pressure on opener
cylinders is maintained at the pressure you
selected while tractor remote lever was held
forward-not at the apparently increased pressure.
Reactivating tractor lever forward will confirm this.
During operation:
• Each time openers are lowered, hold tractor remote
hydraulic lever forward for a few seconds to recharge
circuit, then return it to its neutral position. The tractor
and drill should be on level ground when returning
tractor lever to neutral.
• When approaching rough terrain where you need
active hydraulics to maintain even opener penetration,
push tractor hydraulic lever forward momentarily. As
soon as you return to level ground, return lever to
neutral. Do not activate tractor hydraulic lever for more
than 20 seconds at a time, once every 2 minutes.
Always wait until tractor and drill are on level ground
before returning lever to neutral. You can bump tractor
hydraulic lever forward any time on level ground to
assure the preset pressure is correctly locked in and to
reset the system.
• Always raise openers before turning. Never back up or
turn sharply with openers in the ground. Doing so will
plug openers and may damage equipment.
Figure 22
Pressure Control Valves
34293
Adjustment
Knob
Lock Disk