Thermostat????

[THEFERMANATOR]

What SPARE said. ANY marine engine should have a T-STAT in it. If not you will also have moisture problems in your oil. When the engine runs cold it will sweat inside from the heat of combustion, but the cold engine temps. That sweating will cause water to accumulate in the oil and eventually turn it milky. Also not to mention the fact that to get complete combustion you NEED heat in the engine. There is virtually no good reason to run without a T-STAT other than it can't fail if it isn't there. But to have it there does ALOT more than most people think.