Terex RT700 - Boom Sections Retract Under Load Troubleshooting; Winch Circuit Troubleshooting

TROUBLESHOOTING
TELESCOPE CYLINDER EXTENDS BUT WILL NOT RETRACT
CAUSE REMEDY
Port relief valve sticking .......................................................................See section on “Relief Valves”.
Hold valve malfunctioning....................................................................Repair or replace.
Internal leakage in cylinder...................................................................See section on “Cylinder Leakage”.
Extend valve malfunctioning ................................................................Repair or replace.
BOOM SECTIONS RETRACT UNDER LOAD
CAUSE REMEDY
“O” ring around hold valve damaged....................................................Replace “O” rings.
Hold valve not seating properly ............................................................Repair or replace.
Telescope cylinder by-passing ..............................................................See section on “Cylinder Leakage”.
WINCH WILL NOT DEVELOP MAXIMUM LINE PULL
CAUSE REMEDY
Main relief valve is set too low .............................................................Readjust the main relief.
Main relief valve is sticking..................................................................See section on “Relief Valves”.
Winch motor worn excessively or damaged .........................................See section on “Fluid Motor”.
Tandem pump worn excessively or damaged .......................................See section on “Pumps”.
Rotary manifold leaking internally .......................................................Reseal rotary manifold.
Low oil level..........................................................................................Add oil as required.
WINCH CIRCUIT
RT700 Series Page 5 - 17 Issued: August 2003