Winterizing your 18 yanmar
Alan, If your boat has freash water cooling then your heat exchanger has water on the raw water side. If your engine has raw water cooling then your engine cooling system has raw water in it. Unhooking the water intake does not remove the water and your engine block and or heat exchanger will freeze and break.The easiest solution that I fould was to place your raw water inlet hose into a gallon of plumbers antifreeze (bio-degradable). Start your engine and suck the antifreeze through the cooling system. Making sure that you put enough antifreeze through the system to completly flush out the raw water. If you have fresh water cooling then you should also check your coolant for freeze protection, if necessary replace it.What about the rest of your boat's plumbing such as the water tank, water heater, head and water lines. They all need to be drained and/or flushed also.RegardsJerry