Texas

Texas,

A On the contrary, today’s engines use high-detergent oil. That is how they

stay clean of sludge deposits, despite their high operating temperatures
(assuming the oil is changed regularly according to manufacturer’s specs). I
see no reason why you can’t use today’s detergent motor oil in your boat
engine. The only concern I have is if the engine has not been run in a long
time and it has original seals and wear. Assuming that the seals have been
replaced and OEM tolerances restored, I advise you to use the viscosity oil
recommended by the engine builders in a high-detergent synthetic motor oil
(OEM recommendations being based on the rebuilt engine). AMSOIL makes
a great marine application that would work well in that boat of yours.