Terex RT500-1 - Page 211

SLIP
A SLOW MOVEMENT
OFSTEERING WHEEL FAILS
TO CAUSE ANY MOVEMENT
OF STEERED WHEELS
Leakage of cylinder piston
seals or accessory valve
between cylinder lines or
ports
Replace seals or accessory
valve.
Worn steering control unit
meter
Replace steering control unit.
TEMPORARY HARD
STEERING OR HANG-UP
Thermal Shock* Check unit for proper
operation and cause of
thermal shock.
ERRATIC STEERING Air in system due to low level
of oil, cavitating pump, leaky
fitting, pinched hose, etc
Correct condition and add
fluid.
Loose cylinder piston Replace cylinder.
Thermal shock damage* Replace steering control unit.
Sticking flow control spool Replace flow control valve.
“SPONGY” OR SOFT
STEERING
Air in hydraulic system. Most
likely air trapped in cylinders
or lines
Bleed air out of system.
Low fluid level Add fluid and check for leaks.
FREE WHEELING
STEERING WHEEL TURNS
FREELY WITH NO FEELING
OF PRESSURE AND NO
ACTION ON STEERED
WHEELS
Steering column upper shaft
is loose or damaged
Tighten steering wheel nut.
Lower splines of column may
be disengaged or broken
Repair or replace column.
Steering control unit meter
has a lack of oil. This can
happen on start-up, after
repair, or long periods of non
use
Usually starting engine will
cure problem. If not, stop
engine, discon nect steer
pump outlet hose and pour in
hydraulic oil to prime pump.
No flow to steering unit can
becaused by:
1. Low fluid level
2. Ruptured hose
3. Internal steering control
unit damage due to thermal
shock*
1. Add fluid and check for
leaks
2. Replace hose.
3. Replace the unit.
FREE WHEELING STEERING
WHEEL TURNS WITH
SLIGHT RESISTANCE BUT
RESULTS IN LITTLE OR NO
STEERED WHEEL ACTION
Piston seal blown out Determine cause. Correct
and replace seal.
RT500
Troubleshooting
208 REVISED: