Great Plains PD8070 Operator Manual - Manual (Page 35)

1/24/2006 401-266M
33 Troubleshooting
Planter frame raises or lowers
slowly. Lower tractor hydraulic pressure. Tractor operating pressure must be a minimum
of 1500 psi.
Operate tractor with flow control lever in the unrestricted position. Refer to your
tractor operator’s manual.
Erratic or uneven lift. Check for air in hydraulic system. Bleed system of air if necessary.
Planter will not raise. Tractor hydraulic system bypassing oil. Readjust tractor’s hydraulic lever linkage.
Refer to your tractor operator’s manual.
Markers not alternating. Marker hoses not connected to marker valve correctly.
Check for air in marker valve. Bleed marker hydraulic system.
Marker valve defective. Replace valve. See your Great Plains dealer.
Marker floats off ground. Air in hydraulic system. Bleed marker lift cylinder.
Alternator valve defective. Replace valve. See your Great Plains dealer.
Check for leaks in tractor hydraulic remote.
Marker cylinder not dropping down into J-slot. (Hose loop too short.) Lengthen
marker hydraulic hose loops.
Hydraulic marker functioning
improperly. Check all hose fittings and connections for air and oil leaks.
Check tractor hydraulic oil level.
Check all bolts and fasteners.
If markers do not alternate: check tractor flow controls and set to maximum oil
flow. If problem still exists, disassemble valve and check for contamination or
spool damage.
Blade does not mark. The maximum marker down float is limited by the slot in the pivot link. If the blade
does not drop down to follow depressions in the field, make sure the marker cylin-
der is fully extended.
The blade may be reversed to pull dirt in or throw dirt out depending on soil condi-
tions.
Problem Possible Cause and Solution