Great Plains 3PYPA Operator Manual - Manual (Page 117)

Great Plains Manufacturing, Inc. Table of Contents Index Maintenance and Lubrication 113
03/20/2012 Table of Contents Index 401-647M
Bleeding Hydraulics
Bleeding Lift Hydraulics
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.
If it is necessary to further bleed lift system, see “Lift
Cylinder Bleeding” on page 114.
Bleeding Fold Cylinder Hydraulics
Normally the fold hydraulics are bled at the factory before
shipping, and bleeding should not be required other than
to fold fully and hold lever on for one minute or until all
cylinders reach the end of their stroke.
If it is necessary to further bleed fold system, see “Wing
Fold Cylinder Bleeding” on page 116.
Bleeding Marker Hydraulics
To fold properly, the marker hydraulics must be free of
air. If the markers fold in jerky, uneven motions, see
“Marker Tilt Cylinder Bleeding” on page 118 and see
“Marker Fold Cylinder Bleeding” on page 119.
Null4.aac:
High Pressure Fluid Hazard:
Relieve pressure before disconnecting hydraulic lines. Wear
protective gloves and safety glasses or goggles when working
with hydraulic systems. Escaping fluid under pressure can
have sufficient pressure to penetrate the skin causing serious
injury. Use a piece of paper or cardboard, NOT BODY PARTS,
to check for leaks. If an accident occurs, seek immediate medi-
cal attention from a physician familiar with this type of injury.
Only trained personnel should work on system hydraulics!
System Contamination Risk:
Always use liquid pipe sealant when adding or replacing NPT
(National Pipe Thread, tapered thread) pipe-thread fittings. To
avoid cracking hydraulic fittings from over tightening, and to
keep tape fragments from clogging filters, do not use plastic
sealant tape.
Crushing and Equipment Damage Hazards:
If the planter is folded, and it is suspected that the fold system
has air in it, DO NOT attempt to unfold before accomplishing
the full fold bleed procedure at “Wing Fold Cylinder Bleed-
ing” on page 116.
If the fold system has air in it, the wings can descend too fast.
Crushing and Equipment Damage Hazards:
Do not bleed marker cylinders with wings folded. Avoid bleed-
ing wing fold cylinders with wings folded. The cylinders are
difficult to access when folded, and bleeding complications
could lead to an unsafe or unserviceable machine
configuration.
JIC Torque Chart
Over-Torque Leak Risk:
JIC (Joint Industry Conference 37
° Flare) fittings do not
require high torque. Excess torque causes leaks. JIC and
ORB (O-Ring Boss) fittings do not require sealant.
Note: Bleed only at JIC and NPT fittings.
Never try to bleed a QD (Quick Disconnect) fitting.
Avoid bleeding at ORB fittings. The O-ring is likely
to be torn if any pressure remains in the circuit.
Size Foot-Pounds N-m
7 ⁄
16
-20 11-12 15-16
1 ⁄
2
-20 15-16 20-22
5 ⁄
16
-18 18-20 24-28
3 ⁄
4
-16 38-42 52-58
7 ⁄
8
-14 57-62 77-85
11 ⁄
16
-12 79-87 108-119