If you have temp's that fall below freezing, why do you not have anti freeze?
Others are asking but your not responding?
I live in an area that doesn't have temp's that reach quite that low, but no one would not put anti freeze in their engines, not even in there cars.
And I would think in your area that most responsible boat owners would 'winterise' their engines if not using them too. We generally don't winterise here as our lowest temps are pretty much just above freezing.
It seems odd to me to post a request on CF that is a akin to a post like, 'hey folks I found a hole in my boat, but decided to leave it as it was only a little hole and when I came back my boat had sunk. Any suggestions on why it would have sunk'