Yamaha 15MSH Troubleshooting
| Engine Model: Yamaha 15MSH |
| Engine Type: 2-stroke 2-cylinder short shaft gasoline outboard engine |
| Total Displacement: 15 cu.in (246 cc) |
| Rated Engine Power: 15 Hp (11 kW) at 5500 rpm |
| Fuel System: Carburetor |
____________________________________________________________________________________
| Engine doesn't start or hard to start |
Empty gas tank - Add gasoline.
Wrong grade of gasoline - Use correct fuel grade.
Water or air in fuel system - Remove air or water from system.
Spark plug wire is disconnected or loose - Check the spark plug wire connection, repair or replace.
Spark plug is damaged - Change spark plug.
Dirty fuel filter - Replace fuel filter.
Carburetor components worn out - Repair or replace parts.
Fuel lines clogging - Clean fuel system lines.
Fuel tank air vent restricted or closed - Fuel tank air vent need to be opened or cleaned.
Lack of fuel pump pressure - Install new pump or repair it.
Reed valve is defective or worn - Install new reed valve.
| Engine starts but stalls immediately |
Spark plug is defective - Change spark plug as required.
Defective or dirty carburetor - Clean or install new carburetor.
Ignition coil is defective - Replace ignition coil as necessary.
Closed or clogged fuel tank air vent - Fuel tank air vent need to be opened or cleaned.
Lack of fuel pump pressure - Replace or rebuild fuel pump.
Defective ignition - Check ignition and replace faulty components.
Dirty or damaged fuel pump - Check fuel pump and replace if necessary.
Carburetor settings incorrect - Adjusting as required.
Clogged fuel lines - Clean fuel system lines.
Closed or restricted fuel tank air vent - Open or clean air vent.
Clogged fuel filter - Change fuel filter.
Damaged gaskets - Install new gaskets.
Engine overloaded - Load reducing is recommended.
Carburetor mixture is too lean - Make the correct settings.
Bad ignition timing - Ignition timing needs to be adjusted correctly.
Thermostat is defective - Replace thermostat.
Water pump malfunction - Change water pump as required.
Propeller selection improperly - Install correct propeller.
Propeller bent or damaged - Replace propeller.
Outboard motor is mounted too high or too low - Position the engine correctly.
Stale fuel - Use proper fuel.
Engine overloaded - Reduce load.
Low idle speed setting is incorrect - Correct the settings.
Clogged or damaged fuel pump - Clean or install new fuel pump.
Worn main bearings or crankshaft - Need to install new components.
Worn cylinder bore or piston rings - Replace defective components.
Carburetor is clogged or incorrectly adjusted - Adjust carburetor properly or service it.
Clogged or defective fuel pump - Clean or replace fuel pump.
Ignition failure - Test ignition and replace failed parts.
Gaskets are damaged - Change gaskets.
Worn powerhead components - Replace defective parts.
Improper propeller diameter or pitch - Install correct propeller.
Propeller bent or damaged - Replace propeller.
Motor mounted at incorrect height on transom - Check the outboard engine mounting height.
Trim angle is incorrect - Adjust trim angle correctly.
| Engine using too much gasoline |
Carburetor main jet adjustment is incorrect - Adjust main jet as required.
Spark plug is faulty or loose - Re-tighten or change the spark plug.
Worn sleeve, rings, or piston - Change faulty components.
| Engine vibrates excessively |
Damaged or bent propeller - Have propeller repaired or replaced.
Damaged propeller shaft - Have propeller shaft replaced.
Weeds wraped around propeller - Remove and clean propeller.
Motor mounting bolt is loose - Tighten bolt.
Steering pivot is faulty or loose Tighten or replace.
____________________________________________________________________________________
| Outboard Engines Technical Specifications |
| Small Engines Technical Specifications |
| Car Engines Technical Specifications |
| Industrial Engines Technical Specifications |
