Doosan 7/71 - Page 66

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ENGINE TROUBLESHOOTING
7/71, 12/56
Unstable engine running Crack in injection pipe.
Injection nozzle failure.
Unstable low idling Engine stop solenoid return failure.
Uneven compression pressure between cylinders.
Incorrect high idle speed
adjustment.
Incorrect control lever adjustment.
Governor internal malfunction.
Engine hunting in medium speed
range.
Governor spring deteriorated.
Air in the fuel system
Insufficient fuel supply. Clogged fuel filter element
Piping failure (squeezed/restricted
etc.)
Engine malfunction in high speed
range.
Uneven fuel injection amount between cylinders.
Deteriorated governor spring.
Incorrect valve clearance adjustment.
Deteriorated valve spring.
Engine speed stuck at high idle. Engine control restriction or seizure.
Engine overheat. Insufficient coolant volume.
Fan belt slippage.
Cooling system defect Thermostat malfunction.
Radiator filler cap malfunction.
Cooling system interior fouled.
Radiator clogged.
Engine over−loaded.
Improper servicing Air cleaner element clogged.
Insufficient airflow/restriction.
Restricted coolant flow (high concentration of antifreeze, etc.)
Low oil pressure Lack of oil Oil leakage
High oil consumption
Wrong oil Wrong type and viscocity.
High coolant temperature. Over heat.
Clogged filter and strainer.
Worn bearings and oil pump.
Faulty relief valve.