winterizing

[bcalc]

I am a new boat owner this year. I have a 1989 Merccruiser 3.7 with the alpha 1 drive. This is a closed system so I am not concerned about the engine block, it already has antifreeze in it.
My concern is the sea water side of this cooling system. Should and how do I drain it????????????

or should it be filled with antifreeze????

Thanks
Mike C.

 

[Brewman61]

Re: winterizing

If you'll be exposing the boat to freezing you need to make sure all water is drained.
Two schools of thought on adding anti freeze- One is that if there is no water, there is nothing to freeze, and therefore no need.
Second is to use the anti freeze just to be sure- kinda belts and suspenders.
If you go the antifreeze route, use the RV type (Pink Kool-aid) that has corrosion inhibiters. It's non toxic unlike like standard automotive coolant.
Someone more familiar with your specific engine may be able to guide you thru the draining process. Mine I open a single valve and undo a vent near the thermostat. Your engine is likely not that way.