Great Plains NTA2007 Operator Manual - Manual (Page 125)

Great Plains Manufacturing, Inc. Table of Contents Index Maintenance and Lubrication 121
2012-01-05 Table of Contents Index 166-372M
Bleeding Fold/Lock/Down-Pressure Hydraulics
If the systems have sufficient fluid for safe operation,
prior to bleeding, perform an unfold (page 35) operation
and a lower (page 39) operation.
1. Review safety advice and operational advice on
page 119, and on this page, before performing
bleed.
Note: A complete Fold system re-charge requires about
20 litres (5.4 gallons) of oil.
Refer to Figure 101 and Figure 102
2.
Set Fold circuit to Float.
3. Set both weight-transfer pressure control valves
three turns from fully open. Release lock rings. Turn
knobs fully counter-clockwise. Reverse 3 full turns.
4. Un-pin the wing fold rod ends . Un-pin the cart-
transfer cylinder rod ends . Un-pin the lock cylinder
base end . Block up or wire cylinders so that free
ends may extend without striking drill parts.
5. If extended, completely retract fold and cart transfer
cylinders. Fully extend centre lock cylinder rod.
6. Loosen the JIC fittings at
the base end of both fold cylinders
,
the base end of both transfer cylinders , and at
the rod end of the lock cylinder .
7. Slowly extend the circuit until fluid appears at each
loosened fitting. Set circuit to Neutral and secure
each fitting in turn. Repeat until all five fittings are
secured.
8. Continue to Extend circuit until the fold and transfer
cylinders are fully extended, and the lock cylinder is
fully retracted. Set circuit to Neutral.
9. Loosen the JIC fittings at
the rod end of both fold cylinders
,
the rod end of both cart transfer cylinders , and at
the base end of the lock cylinder .
10. Slowly retract the circuit until fluid appears at a
fitting. Set circuit to Neutral and secure fitting.
Repeat until all five fittings are secured.
11. Cycle cylinders full stroke several times.
12. Use tractor circuit to re-position rod ends and re-pin.
13. If no other bleeding is required, adjust the transfer
control valves back to their most recent settings (or
to the suggested default settings). See page 90.
Figure 101
Fold Bleed Points
31225
1
5
2
8
1
2
3
4
5
6
7
Figure 102
Lock Cylinder
31226
6
7
3
4
9
8
9
4