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Mariner 135 Troubleshooting

Engine Model: Mariner 135 Hp
Engine Type: 2-cycle 6-cylinder gasoline outboard engine
Total Displacement: 121.9 (1998 cc)
Rated Engine Power: 135 Hp (100.6 kW) at 5500 rpm
Fuel System: Float type carburetor with adjustable jet


Engine hard starting or not starting

Fuel tank is empty - Fill it up.
Incorrect fuel grade - Use correct gasoline grade.
Air trapped in fuel system - Bleed air.
Defective wiring connection of spark plug - Check spark plug wiring connection, repair or change.
Spark plug is damaged - Change spark plug.
Dirty fuel filter - Fuel filter needs changing.
Carburetor settings incorrect - Adjusting as required.
Fuel lines are dirty - Clean fuel lines.
Closed or clogged fuel tank air vent - Open or clean air vent.
Fuel pump pressure is low - Change or rebuild fuel pump.

Engine stalls after starting

Spark plug is faulty - Spark plug need to be replaced.
Carburetor is defective or dirty - Clean or change carburetor.
Ignition coil is faulty - Replace ignition coil as necessary.
Closed or clogged fuel tank air vent - Open or clean air vent.
Fuel pump pressure is low - Change or rebuild fuel pump.
Thermal relief valve is faulty - Change as required.

Engine runs irregularly

Defective ignition - Check ignition and replace faulty components.
Fuel pump is clogged or faulty - Test fuel pump and change if necessary.
Problems with carburetor adjustment - Adjust as required.
Fuel lines are dirty - Clean fuel system lines.
Closed or restricted fuel tank air vent - Open or service air vent.
Fuel filter is clogged - Change fuel filter.
Gaskets are worn - Replace gaskets.

Engine overheated

Engine is under excessive load - Reduce the load.
Too lean carburetor mixture - Make the correct settings.
Incorrect ignition timing - Set the ignition timing properly.
Thermostat is faulty - Install new thermostat.
Water pump is defective - Water pump need to be replaced.

Engine knocks or noises

Low octane fuel - Use proper fuel.
Engine overloaded - Reduce load.
Incorrectly set low idle speed - Correct idle settings.
Fuel pump is clogged or faulty - Test fuel pump and replace if necessary.
Main bearings or crankshaft wear - Worn parts replacement required.
Damaged cylinder bore or piston rings - Change defective components.

Engine power is insufficient

Carburetor is dirty or incorrectly adjusted - Clean or properly adjust carburetor.
Fuel pump is clogged or faulty - Inspect fuel pump and change as required.
Defective ignition - Check ignition system and replace faulty parts.
Damaged gaskets - Change gaskets.
Powerhead parts are damaged - Replace defective components.

Engine uses too much fuel

Improper carburetor main jet adjustment - Adjust the carburetor main jet properly.
Faulty or loose spark plug - Re-tighten or change the spark plug.
Worn sleeve, rings, or piston - Replace defective parts as required.

Trim motor runs but system does not move

Low oil level - Checking oil level and add if necessary.
Defective pump assembly - Check pump and change if required.
Manual release valve leaking - Close the valve or change it.
Pump driveshaft or motor damaged - Change worn component.

Trim cannot be fully up or down

Pump assembly faulty - Change pump.
Tilt ram piston ball is not positioned correctly - Service or repair.
Worn tilt ram piston O-ring - Install new O-ring.
Oil level low - Fill up oil.
Lower check valve is not properly secured in port side trim ram - Secure valve properly.