Yanmar 3TN84L Troubleshooting
| Engine Model: Yanmar 3TN84L |
| Engine Type: 4-cycle 3-cylinder direct injection liquid-cooled diesel |
| Total Displacement: 87.2 cu.in (1.43 L) |
| Rated Engine Power: 28 Hp (20.9 kW) at 2800 rpm |
| Aspiration Type: Naturally aspirated |
____________________________________________________________________________________
| Diesel engine hard to start or doesn't start |
Fuel filter element is dirty - Service the filter.
Air trapped in fuel system - Bleed air.
Defective or clogged injection nozzle - Clean or replace injection nozzles.
Faulty fuel injection pump - Repair or install a new fuel pump.
Wrong valve timing - Correct or replace timing gear.
Plugged fuel pipes - Clean or change fuel pipes.
Unadjusted injection timing - Adjust according to specifications.
Worn piston rings and cylinder - Change defective components.
| Engine stalls after starting |
Dirty fuel filter - Change filter element.
Defective fuel injection pump - Replace or rebuild injection pump.
Air cleaner is dirty - Clean or replace the element.
Incorrect nozzle opening pressure - Set up as recommended.
| Engine stalls while running |
Wrong setting of fuel injection pump timing - Use the correct fuel injection pump timing adjustment.
Clogged fuel filter - Install new filter element.
Engine is cold - Normalize the temperature by warming up the engine.
Defective or stuck injection nozzles - Change or repair injection nozzles.
| Engine stops while idling |
Improperly adjusted low idle speed - Correct low idle settings.
The valve clearance is incorrect - Check and adjust as required.
Fuel injection pump failure - Repair or replace injection pump.
Dirty or damaged injection nozzles - Replace injection nozzles.
Dirt in the fuel hoses or lines - Clean fuel system lines and hoses.
Plugged air filter - Service or replace the air filter.
Damaged cylinder-head gasket - Install a new gasket.
Injection timing is wrong - Use correct injection timing adjustment.
Fuel injection pump is defective - Change pump or rebuild it.
One of moving engine components has failed - Repair or replace defective components.
Clogged radiator core or leaking radiator cap - Clean radiator or replace cap.
Insufficient coolant fluid - Add coolant fluid and inspect the cooling system for leaks.
Loose or defective fan belt - The fan belt needs to be replaced.
Engine oil insufficient - Check and refill engine oil.
Blown cylinder head gasket - Replace cylinder head gasket.
Wrong injection timing - Adjust according to specifications.
Engine oil insufficient - Check oil level and add oil as required.
Defective oil pump - Replace as required.
Oil filter clogged - Replace or service engine oil filter.
Worn or dirty relief valve - Replace or clean relief valve.
Clearance of crankshaft bearing is excessive - Test and repair or replace worn parts.
Excessive crankpin bearing clearance - Test and repair or replace worn parts.
| Engine consuming too much oil |
Oil leaking: Gaskets or seals may be damaged - Install new components.
Wrong oil viscosity - Use oil of proper viscosity.
Seized or wear piston rings - Install new piston rings.
Valve guides and stems are worn - Valves need to be changed.
Pistons or cylinder liners are damaged - Check pistons and liners, replace as required.
Low coolant temperature - Normalize the temperature by warming up the engine.
Insufficient engine oil - Need to add engine oil.
Fuel injection pump timing is wrong - Adjust as recommended.
Worn or scored pistons - Pistons need to be replaced.
Misaligned or defective connecting rod - Need to align or replace the connecting rod.
Low battery output voltage - Recharge the battery.
Battery won’t hold charge - Service charging system or install new battery.
Bad terminals or disconnected battery cables - Connect wiring properly or install new terminals.
Battery is discharged or worn - Recharge or change battery.
Wiring is improperly connected or disconnected - Check wiring and connect properly.
Low battery output - Battery is drained, recharge it.
Starter motor failing - Replace or repair starter.
____________________________________________________________________________________
| Industrial Engines Technical Specifications |
| Small Engines Technical Specifications |
| Car Engines Technical Specifications |
| Outboard Engines Technical Specifications |
