TROUBLESHOOTING
JH Series Operation Manual
137
TROUBLESHOOTING CHART
Symptom
Probable Cause
Measure
Indicators light on the
instrument panel and alarm
sounds during operation
Shift to low speed operation immediately, and check which indicator has come on. Stop the
engine and inspect. If no abnormality is identified and there is no problem with operation, return
to port at lowest speed and request repairs.
Engine does not start or starts with difficulty
Pinion gear does not engage
Loose terminal of battery/engage
magnet
Tighten
Poor contact of starting switch
Correct with sandpaper or replace
Open coil of magnet switch
Replace
Burr at gear tooth tip
Correct
Poor clearance between pinion and
ring gear
Correct
Pinion gear is engaged with
ring gear, but does not rotate
Loose battery/starter terminal
Tighten
Poor contact of starting switch
Correct with sandpaper or replace
Worn brush
Replace
Open circuit of starter coil
Replace
Slippage of starter/clutch
Replace
Excessive resistance of cable
between battery and starter
Increase the cable size or shorten
Insufficient battery charge
Charge
No fuel injection
Incomplete priming of fuel system
Carry out sufficient priming
Clogged fuel inlet filter
Replace
Fuel level in fuel tank is low
Add fuel
Closed cock of fuel tank
Open cock
Clogged fuel pipe
Clean
Failure of fuel supply pump
Repair or replace
Failure of fuel injector
Faulty valve seat
Replace
Sticking of nozzle
Replace
Worn nozzle
Replace
Clogged injection hole
Replace
Failure in fuel injection system
Loose fuel injection pipe joint
Tighten
Broken fuel injection pipe
Replace
Air trapped in fuel injection pipe
Bleed air from pipe
Engine compressed air leak
Air leak from exhaust valve
Carry out fitting of valve and seat
Faulty gasket/packing
Replace
Worn upper portion of cylinder
Replace
Worn piston ring
Replace
Sticking piston ring
Overhaul or replace
Broken valve spring
Replace
No revolution indication on
Tachometer during cranking.
Poor connection of crank & cam
position sensors.
Check connection of the wire harness
Other
Failure of engine system
Conduct servicing
Clogged intake or exhaust pipe
Clean
Controller defects system error
Check DTC and conduct servicing
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