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System Faults Possible causes Solutions
HST
When operating HST
pedal, tractor dose not
start.
▲ Low pressure relief set is too
low
▲ High pressure relief set is too
low
▲ HST charger valve fault
▲ Filter clogged
▲ Pump worn or part damaged
▲ HST moving part worn or
damaged
▲ Check and repair
▲ Check and repair
▲ Replace
▲ Replace filter
▲ Repair or replace
▲ Repair or replace after
check the circuit
Tractor is still moving
despite pedal bring in
neutral position on
HST pedal.
▲ Neutral position of HST pedal
is changed.
▲ HST pedal linkage damaged
▲ HST arm bolt loosened
▲ Adjust neutral position
▲ Replace damaged part
▲ Fasten the bolt with
adhesive
HST power is too low
▲ Oil shortage
▲ Air in HST circuit
▲ Transmission oil temperature
is too high.
▲ HST moving part worn
▲ HST filter clogged
▲ Add oil
▲ Check and repair the
hydraulic suction line.
▲ Stop engine to cool the oil,
and restart
▲ Repair or replace
▲ Replace the filter
Abnormal noise
▲ Engine speed is too low
▲ Oil temperature is too low
▲ Hydraulic oil filter clogged
▲ Oil shortage
▲ Set engine rpm over 1500
rev/min
▲ Run engine to warm up
the oil.
▲ Replace the filter
▲ Add oil