Re: Water in my Oil,l Mercury 115 EFI 4stroke
You need to check your thermostat. If the thermostat is stuck open, or damaged by corrosion or what have you, this will cause water in the fuel, and running issues. If the motor can never reach proper operating temperature, you will develop condensation in the oil pan which can accumulate quickly, and turn the oil milky. This is actually pretty common. Alot of folks seem to think that if their motor is not overheating, then the cooling system must be fine. Also, a motor that runs cold, is usually a motor that runs rich. If the computer doesn't see a warm engine, it will adjust the fuel injector pulse width, and timing curve as though the motor is cold. You didn't mention what year the motor is, but I'm guessing it's a Mercaha. (Mercury 4 stroke built by Yamaha) Thermostat is located at the very top of the motor, underneath the large plastic shield. You will see a gray 5/8 inch hose going into the thermostat housing. Remove the two bolts and check it out. I suspect this toi be your problem. I hope this is a new issue, as water in the oil can do serious mechanical damage to your engine, such as washing the crank bearings. Good luck!!
