Bleeding hydraulics, Bleeding lift hydraulics, Bleeding fold and lock cylinder hydraulics – Great Plains 3N4010HDA Operator Manual User Manual
Page 58
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3N-4010HDA
Great Plains Manufacturing, Inc.
196-444M
2013-09-24
Bleeding Hydraulics
This section covers standard drill hydraulics. See also
“Bleeding Marker Hydraulics” on page 61.
Bleeding Lift Hydraulics
The lift system is equipped with rephasing hydraulic
cylinders requiring a special procedure for bleeding air
from the system. Read and follow the procedure
carefully.
1.
Lower drill to ground.
2.
Unpin rod ends of all six lift cylinders. Pivot cylinders
up and wire or otherwise safely support rod ends
higher than base ends. You may need to remove the
gauge-wheel cylinders from the rockshaft so you can
orient them with rod ends higher than base ends.
3.
With the tractor engine at idle speed, energize the lift
hydraulics. When the cylinders have extended com-
pletely, hold the remote lever on for one minute.
Check all hydraulic hoses, cylinders and fittings for
leaks.
4.
Retract the cylinder rods. Extend the rods again and
hold the remote lever on for one more minute.
Repeat this step two more times.
5.
Again, check all hydraulic hoses, cylinders and fit-
tings for leaks. Recheck the tractor hydraulic reser-
voir. Fill to the proper level.
6.
Re-pin all cylinders.
Bleeding Fold and Lock Cylinder Hydraulics
The fold system is equipped with rephasing hydraulic
cylinders requiring a special procedure for bleeding air
from the system. Read and follow the procedure
carefully.
Bleeding Lock cylinders
1.
Unpin the small lock cylinders, pivot cylinders so the
rod end is free to move.
2.
Crack fittings at base end of cylinders. Extend cylin-
ders to purge air from system. Tighten fittings.
3.
Crack fittings at rod end of cylinders. Retract cylin-
ders to purge remaining air from system. Tighten fit-
tings.
4.
Repeat step 2 and step 3.
5.
Re-pin small lock cylinders.