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Mercury XRI 150 Troubleshooting

Engine Model: Mercury XRI 150 Hp
Engine Type: 2-cycle 6-cylinder gasoline outboard engine
Total Displacement: 153 (2507 cc)
Rated Engine Power: 150 Hp (111.8 kW) at 5600 rpm
Fuel System: Electronic fuel injection (EFI)


Engine difficult to start or doesn't start

Empty fuel tank - Fill fuel up.
Wrong grade of gasoline - Use quality fuel.
Fuel system clogged - Repair or replace.
Spark plug wire is loose or disconnected - Inspect the spark plug wire connection, replace or repair.
Spark plug is faulty - Replace spark plug.
Fuel filter is dirty - Replace or clean fuel filter.
Dirty fuel lines - Clean fuel system lines.
Drained or defective battery - Charge or change the battery.
Damaged wiring harness connections - Check electrical wire harness connections.
Damaged ignition system - Change defective parts.
Pulse fuel pump failure - Install new pulse fuel pump.
Electric fuel pump is faulty - Change electric fuel pump as required.
ECM is faulty - Replace ECM.

Engine starts and stalls immediately

Faulty spark plug - Change spark plug as required.
Damaged ignition coil - Ignition coil must be replaced.
Defective pulse fuel pump - Change pulse fuel pump.
Fuel system is dirty - Service fuel system.
Dirty final fuel filter - Final filter needs changing.
Electric fuel pump is defective - Replace electric fuel pump.

Irregular engine running

Ignition failure - Check ignition and replace faulty components.
Fuel pump is clogged or faulty - Service or replace fuel pump.
Clogged fuel lines - Fuel lines must be clean.
Fuel filter is plugged - Install new filter.

Engine overheating

Engine overloaded - Reduce load.
Wrong ignition timing - Set the ignition timing correctly.
Faulty thermostat - Change thermostat.
Water pump failure - Water pump need to be replaced.

Abnormal engine knocking or noise

Stale or low octane fuel - Use proper gasoline.
Engine overload - Load reducing required.
Low idle speed adjustment is incorrect - Need to adjust idle speed.
Fuel pump is clogged or faulty - Check fuel pump and change if required.
Main bearings or crankshaft failure - Repair or replace defective parts.
Damaged cylinder bore or piston rings - Replace faulty parts.

Loss of engine power

Clogged or defective fuel pump - Clean or change fuel pump.
Ignition system malfunction - Check ignition and replace faulty components.
Faulty powerhead parts - Defective parts need to be replaced.
Failed switch box, stator, or coil - Change damaged parts.
Compression is insufficient - Normalize compression.
Fuel delivery problem - Check fuel system.
Manifold fuel leak - Leak must be repaired.
Vapor separator flooding over - Check and correct malfunction.

Excessive fuel consumption

Spark plug is loose or defective - Tighten or change the spark plug.
Piston, sleeve, or rings are damaged - Replace defective components as required.
Engine is overloaded - Load reducing required.
Dirty or damaged fuel injectors - Check fuel injectors and change if required.

Trim motor is running but system can't move

Oil insufficient - Checking oil level and add if necessary.
Pump assembly faulty - Check pump and change if required.
Manual release valve leaking - Close the valve fully or replace it.
Faulty pump driveshaft or motor - Change worn component.

Trim does not fully up or down

Pump assembly is faulty - Change pump.
Tilt ram piston ball is not positioned correctly - Service or repair.
Tilt ram piston O-ring is worn - Change O-ring.
Oil level is low - Check oil level and add oil as required.
Lower check valve not seating in port side trim ram - Secure valve properly.