LS tractor LB1300 - Page 85

83
SERVICE MANUAL(VALVE)
Troubleshoot guide
Sl .No
Problem
Root cause
Action
1
Absolutely no functioning
of the control valve
Engine is not running
Check the engine
Low oil level in the tank
Check the oil level and refill to specified limit
Pump is not delivering the
oil
Check the pump direction of rotation
Pump coupling may be
Disengaged
Check the coupling
Main relief valve may be
unscrewed fully
Set main relief valve to required pressure
(pressure setting can be done by connecting
the pressure gauge to the inlet of con- troll
valve and actuating any one operation at full
RPM)
Main relief valve may be
Jammed
Disassemble the main relief valve clean it
2
Any one operation not
functioning
Spool in the valve may be
Jammed
Remove the spool and clean it
The port relief valve may
be jammed
Remove and clean the port relief valve
Main compensator may be
Jammed
Disassemble and check the main compensator
on inlet cover
Coil may not work
Properly
Replace the coil part
Electric line may be cut
Check the electric line and replace it
3
Cycle time slow
in all operations
Main relief valve pressure
may be less than design
pressure
Check the main relief valve pressure and set as
specified in the drawing
Main relief valve pressure
may have leakage
Check chips inside relief valve
Replace the main relief valve
4
Uncontrolled movement in
any operation
Insufficient oil supply
Check the oil level
Cavitation generating in the
system
Check the fitting and components
torque(required torque can available in the
exploded drawing)
5
Required load not lifting
Engine RPM may be less
Check the engine RPM
Main relief valve pressure
may be less
Set the main relief valve pressure to design
pressure(note: increase in main relief valve
pressure more than design pressure may
damage the pump or cylinder or structure)
6
External leakage seen on
the control valve
Seals may be damaged or
missing
Check the seals and replace if it damaged
Fittings or components
are not tightened to
required torque
Check the fitting and components
torque(required torque can available in the
exploded drawing)
7
Pump or cylinder or control
valve failure at the end
stroke
Main relief valve pressure
may be tampered or
jammed
Check the main relief valve pressure
Due to spike generated in
the system
Check the port relief setting