Terex RT700 - Steering Circuit Troubleshooting

TROUBLESHOOTING
RT700 Series Page 5 - 6 Issued: August 2003
STEERING CIRCUIT
Most steering problems can be corrected if the problem is properly defined. The entire steering system should be evaluated be-
fore removing any components. The steering control unit is generally not the cause of most steering problems. The following
is a list of steering problems along with possible causes and suggested corrections.
SLOW STEERING, HARD STEERING, OR LOSS OF POWER ASSIST
- -CAUSE- -REMEDY-
Worn or malfunctioning pump................................................................................Replace pump.
Stuck flow divider piston ........................................................................................Replace flow divider.
Malfunctioning relief valve allowing the system
pressure to be less than specified ............................................................................Replace the relief valve.
Overloaded steer axle..............................................................................................Reduce load.
Leaking or kinked load sensing signal line.............................................................Correct.
Malfunctioning priority valve.............. ...................................................................Check spring and sticking piston.
Check damping orifices in both ends
of main bore.
Check adjustment See page 5-6.
Check system pressure at SCU inlet
for proper system pressure. If not
correct replace priority valve relief
cartridge.
WANDER
VEHICLE WILL NOT STAY IN A STRAIGHT LINE
-CAUSE- -REMEDY-
Air in the system due to low level of oil,
cavitating pump, leaky fitting, pinched hose, etc....................................................Correct.
Worn mechanical linkage........................................................................................Repair or replace.
Bending of linkage or cylinder rod .........................................................................Repair or replace.
Loose cylinder piston ..............................................................................................Repair or replace.
Severe wear in steering control unit........................................................................Replace the steering control unit.