Cummins ISB3.9 Troubleshooting
| Engine Model: Cummins ISB3.9 |
| Engine Type: 4-cycle inline 4-cylinder direct injection liquid-cooled diesel |
| Total Displacement: 239 cu.in (3.9 L) |
| Rated Engine Power: 75-170 Hp (56-127 kW) at 2400 rpm |
| Aspiration Type: Naturally aspirated or turbocharged |
____________________________________________________________________________________
| Engine hard to start or will not start |
Fuel filter plugged - Change filter element.
Air trapped in fuel system - Bleed air.
Fuel injection nozzles are clogged or faulty - Install a new kit of correctly balanced nozzles.
Faulty fuel injection pump - Change pump or rebuild it.
Unadjusted valve timing - Correct or change timing gear.
Restricted fuel pipes - Clean or replace fuel pipes.
Improper injection timing - Use correct injection timing adjustment.
Worn piston rings and cylinder - Replace faulty parts.
| Engine starts but stops suddenly |
Clogged fuel filter - Service or replace the filter.
Fuel injection pump is not operating properly - Install a new pump or rebuild.
Plugged air filter - Replace air filter element.
Incorrect nozzle opening pressure - Adjust as required.
| Engine stalls during operation |
Fuel injection timing is not adjusted - Use the correct fuel injection pump timing adjustment.
Fuel filter plugged - Clean or change the filter.
Engine has not warmed up to the recommended temperature - Warm up engine as required.
Injection nozzles are burnt or jammed - Repair or change injection nozzles.
| Engine stops at low idle speed |
Improperly adjusted low idle speed - Adjustment required.
Valve clearance is out of adjustment - Check and adjust.
Fuel injection pump is defective - Change pump or rebuild it.
Fuel injection nozzles are faulty or clogged - Install a new kit of correctly balanced nozzles.
Dirty fuel hoses or lines - Service fuel lines and hoses.
Dirty air filter - Replace air filter element.
Leaking cylinder head gasket - Cylinder-head gasket replacement required.
Incorrect injection timing - Adjust according to specifications.
Fuel injection pump failure - Install a new pump or rebuild.
One of moving engine parts is faulty - Repair or replace defective components.
Defective radiator cap or clogged radiator fins - Install new cap or clean radiator.
Low engine coolant - Add coolant fluid and inspect the cooling system for leaks.
Broken or loose fan belt - Fan belt must be replaced.
Engine oil level is low - Add oil to the engine crankcase.
Cylinder head gasket is defective - Cylinder-head gasket replacement required.
Injection timing is out of adjustment - Adjust according to specifications.
Oil level is low - Fill crankcase to proper oil level.
Defective oil pump - Install a new pump.
Oil filter clogging - Clean or change engine oil filter.
Stuck or worn relief valve - Replace or clean relief valve.
Excessive oil clearance of crankshaft bearing - Inspect and replace or repair faulty components.
Excessive oil clearance of crankpin bearing - Test and repair or replace worn parts.
Oil leakage: Worn seals or gaskets - Change to repair leaks.
Crankcase oil too light - Use oil of proper viscosity.
Piston rings are seized or worn - Replace piston rings.
Valve guides and stems are worn - Valves need to be changed.
Cylinder liners or pistons are scored - Inspect pistons and liners, fit new components as necessary.
Engine not warmed up - Normalize the temperature by warming up the engine.
Low engine oil level - Check and refill engine oil.
Incorrect adjustment of fuel injection pump timing - Use the correct fuel injection pump timing adjustment.
Broken or worn pistons - Install new pistons.
Connecting rod misalignment or failure - Connecting rod needs to be aligned or changed.
Battery capacity is low - Battery is drained, charge it.
Battery will not hold charge - Service battery or change it.
Disconnected cables or faulty battery terminals - Connect wiring properly or install new terminals.
Battery is discharged or defective - Recharge or change battery.
Wiring is improperly connected or disconnected - Check wiring and connect properly.
Low battery power - Charge the battery.
Defective starter motor - Repair or install a new starter.
____________________________________________________________________________________
| Industrial Engines Technical Specifications |
| Small Engines Technical Specifications |
| Car Engines Technical Specifications |
| Outboard Engines Technical Specifications |
