Winterizing after a year on the hard

Hi everyone. Last winter we were in indoor storage, so didn't have to worry about winterizing. We decided not to launch this spring given the uncertainty of the pandemic, but did move outside. We will be outside in this Wisconsin winter.
So I'm wondering, given that the boat has been out of the water for a year, if I'll need to winterize the raw-water system. I replaced all the intake hoses up to the water pump in order to install a raw-water filter. The exhaust has been disconnected from the thru-hull for most of the summer, but the exhaust hose was not replaced.

Would there still be water in the heat-exchanger and mixing elbow?

I'm leaning towards running anti-freeze through from the raw water pump intake to exhaust for piece of mind. That simplifies things and doesn't fill the new, dry, raw water strainer.

I though it would be worth asking as I always appreciate all of your thoughts and advice.

I do plan to run pink propelene glycol through the freshwater system, as I imagine there is residual water there in small tubes. The head is currently being completely replumbed so no worries there.
Oil and all filters were changed prior to haulout in fall '19 so wasn't planning on doing anything else to engine systems. I plan to replace the impeller in the spring.

Thanks in advance! -Tyler

I have once had to winterize our engine when it was 20 degrees for several days. (I needed to take it to a yard, and so un-winterized it in order to move it.)
Once lifted and put on blocks, the yard gave permission to fire it up for a minute and suck pink antifreeze thru the whole system until it started to burp out the exhaust and then shut 'er down.
I have a hose fitting on the engine intake thru-hull that allows me to attach a short hose that drops into a jug of pink "RV" antifreeze. Lacking that, one could remove the intake hose from the thru-hull and add a hose with an adapter, to also get the end into that jug of 'pink'.
Our three cylinder engine raw water part of the system takes about 3 quarts into it before we shut it off. This protects the strainer, heat exchanger, and water lift muffler.

You're in Wisconsin, what a coincidence. We have our boat at the Port Superior Marina just south of Bayfield. We've been there since 88.
I disconnect the engine water intake hose that attaches to the impeller. Then I attach a short hose to the impeller and use it to suck the water out of two -100 bottles of RV antifreeze. Two gallons is enough antifreeze to make it out my exhaust. I then open the water intake through hull and blow out any remaining water.
It sounds like you have everything else covered. The only other thing we do is to run antifreeze through the bilge pump. I once had a problem when we were healed over to port and pumped the bilge. After we shut off the bilge pump water siphoned in, so I put in a check valve where the hose connects to the bilge pump.

Bob Robertson said:

You're in Wisconsin, what a coincidence. [...] The only other thing we do is to run antifreeze through the bilge pump. I once had a problem when we were healed over to port and pumped the bilge. After we shut off the bilge pump water siphoned in, so I put in a check valve where the hose connects to the bilge pump.

Click to expand...

Hey Bob. We're storing at Great Lakes Marine in Port Washington, but sail out of McKinley Marina in Milwaukee. We chartered a C&C 29 for a week in the Apostles a couple years ago, and took the ASA 103/4 course out of your harbor with a sail out to Big Bay. I love your cruising grounds up there and hope to make it up to Lake Superior someday on our boat.

Thanks for the advice on the bilge pump. I had thought to pour some antifreeze in the bilge but would not have thought to pump it through.

Thanks also to both you and Loren for quantities on antifreeze!