I just got a used 15 hp honda four stroke and it seems to be in great shape. The oil is clean the plugs look good and the fuel filter is brand new. All the outboards I have ever owned have been two stroke so I am wondering what other maintenence needs to be kept track of besides fuel filter, engine oil, air filter, spark plugs, and lower unit oil.
Do you know the history? Change the oil no matter how it looks.
Change the water pump impeller. Change the lower unit gear lube.
Use a fuel stabalizer in the gas tank.
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