Take Wakinas advice my friend, you are looking at disaster if that block freezes! Not worth the risk. Maybe you can at least find the drain plugs on each side of the block and drain the water from it. I'm not sure where they are on your boat but you should be able to find out on the web. My engine has 5 different drain plugs that can be removed by hand and only takes a few minutes to do.

Best of luck to you and don't delay!