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ENGINE TROUBLESHOOTING
87
9/275, 9/305, 12/250, 17/240, 21/220
This item contains a simple troubleshooting. When a failure takes place on your engine, diagnose the cause referring this troubleshooting. Should
the cause of failure not be detected or you are unable to manage the failure, consult your machine supply source or nearest company engine service
outlet.
Engine does not start
Starter does not turn.
Battery discharged
Bad cable connections.
Starter or starter switch failure.
Safety relay failure.
Starter turns but engine does not
fire.
No fuel injection.
Engine stop solenoid malfunction.
No fuel in the fuel tank.
Clogged fuel filter element.
Air in the fuel system.
Fuel is injected but engine does
not fire.
Incorrect preheating operation.
Glow plug malfunction.
Incorrect injection timing.
Low cylinder compression
pressure.
Engine fires but stalls
immediately.
Air in the fuel system.
Compressor air inlet valve remains open during startup.
Unstable engine running
Unstable low idling
Crack in injection pipe.
Injection nozzle failure.
Uneven compression pressure between cylinders.
Engine malfunction in high speed
range.
Insufficient fuel supply.
Air in the fuel system
Clogged fuel filter element
Piping failure (squeezed/restricted
etc.)
Uneven fuel injection amount between cylinders.
Incorrect valve clearance adjustment.
Deteriorated valve spring.
Engine speed stuck at high idle.
Engine overheat
Cooling system defect
Insufficient coolant volume.
Fan belt slippage.
Thermostat malfunction.
Radiator filler cap malfunction.
Cooling system interior fouled.
Radiator clogged.
Improper servicing
Engine over-loaded.
Air cleaner element clogged.
Insufficient airflow/restriction.
Restricted coolant flow (high concentration of antifreeze, etc.)