Shibaura CM284 - Trouble Shooting

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5. TROUBLE SHOOTING
Most malfunctions in the steering system can usually be
traced to dirt or foreign matter in the system. Dirt can
cause such things as stickiness, erratic operation, or hard
steering.
Before considering the procedures below, follow these
suggested steps:
1. Check the pump for proper relief valve action. See
“Pressure Testing”, discussed in this section.
2. Jack the rear end of the tractor off the ground and
cycle the steering from stop to stop to check for rear
axle binding.
3. Be sure the hydraulic hoses from the
pump-to-control valve and from the control
valve-to-cylinder are hooked up correctly.
NOTE: If the steering system oil continues to overheat above 200º (93ºC), seals in the system can shrink, harden
or crack thus losing steering ability.
CONDITION POSSIBLE CAUSE CORRECTION
Clicking noise
Steering wander
High steering effort
Excessive heat
Hard Steering
1. Steering components loose and
shifting under load.
1. Tire pressure incorrect.
2. Worn tie rod ends.
3. Steering column shaft binding.
1. Low pressure.
2. Steering motor binding.
1. Kinked hose.
2. Bent tubes.
3. Restricted re-centering of steering
motor.
1. Lack of transmission oil.
2. ORBITROL (control valve unit)
(1) ORTITROL not aligned to
steering column.
(2) Spool-and-sleeve combination is
seized because of foreign matter.
(3) Over tightening of the end cap
bolts.
3. Oil pump (HST Charge Pump)
(1) The pump is stuck and will not
work.
(2) The pump is worn down.
(3) Pumping performance
inadequate.
4. Relief valve
(1) The valve is damaged because
of internal deterioration.
(2) Pressure setting is too low.
Check and correct.
Check tire pressure.
Replace.
Remove and correct.
Check pressure.
Check and repair.
Check hose routing.
Check tubes.
Repair as necessary.
Fill the transmission oil.
Reposition ORBITROL. (If loosening
its mounting bolts lightens the
handwheel, it means that ORBITROL
was in misalignment).
Replace.
Re-tighten to the specified torque limit.
Replace oil pump. (HST Charge Pump)
Replace oil pump. (HST Charge Pump)
Test pump performance and, if
necessary, remove the pump.
Disassemble the pump and replace the
internal seals.
Replace control valve assembly.
Replace control valve assembly.