GREAT PLAINS Yield-Pro Air-Pro YP2425A, Operator'S Manual

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Great Plains | 401-626M | 2019-06-11 Table of Contents Index 108
YP2425A Table of Contents Index Maintenance and Lubrication
Lift System Bleeding
Normally the lift hydraulics are bled at the factory before
shipping, and bleeding should not be required other than
to raise fully and hold lever on for one minute or until all
cylinders extend fully.
Lift Cylinder Bleeding
Refer to Figure 141
1. Unfold and lower planter.
2. Unpin rod ends of all lift cylinders. Position cylinders
so that rod ends may extend without striking
machine parts.
3. Loosen the JIC fittings at the base end of each
master lift cylinder.
4. Extend the circuit until fluid appears at the loosened
fittings. Set circuit to Neutral and secure fittings.
5. Loosen the JIC fittings at the base end of each
slave lift cylinder.
6. Extend the circuit until fluid appears at the loosened
fittings. Set circuit to Neutral and secure fittings.
7. Re-pin rod ends.
Marker Maintenance
Marker Bleeding
To fold properly, the marker hydraulics must be free of
air. If the markers fold in jerky, uneven motions.
Marker Cylinder Bleeding
Refer to Figure 143
1. Begin with planter unfolded and lowered, and with
both marker sides extended. See “ Unusual Marker
Operations ” on page 40.
2. Note the position of the gravity pin lock (above and
latched on rod-end pin when folded, hanging down
when unfolded).
3. Unpin the rod end of the marker cylinders, and orient
the cylinders so that the rods may extend without
striking marker components.
4. Loosen the JIC fitting at the base end of one
marker cylinder.
5. Extend the circuit until fluid appears at the loosened
fittings. It may be necessary to extend-retract-extend
to cycle the sequence valve to that marker. Set
circuit to Neutral. Secure fittings.
6. Loosen the JIC fitting at the rod end of that same
marker cylinder.
Figure 142
Fold Bleed
29577
3
1
2
4
1
3
2
4
1
2
Figure 143
Marker Bleed
26131
2
1
1
2
1
2