Winterize your boat

https://preview.redd.it/7gsrfmzloqkg1.jpeg?width=1536&format=pjpg&auto=webp&s=293778edbe874caed71055acff9fcee0d66f7335

I second the need to close the engine cooling loop seacock during the winter. This is my father-in-law's 32 foot sailboat near Annapolis MD a few weeks ago. Most of this is not liquid water, it is ice. Temps got down to the teens and stayed in the 20s or less for over a week. In the Potomac river only the shipping channel was ice free. The marina had notified father-in-law that the boat was listing, apparently grounded, then sent pictures of what they found. When things near the seacock had thawed it was clear that water was leaking in at the seacock which was not closed. I can't tell from photos and video provided what is actually broken ir cracked. I have also heard this is the second time this boat has sunk at the dock due to this seacock. My personal recommendation would be to put together a docking checklist, laminate it, and stick it to the wall next to the breaker panel or wherever the engine key is and attach a grease pencil to that key so items can be checked off before starting the engine and leaving the dock and after returning to the dock. As this is my father-in-law's boat and my advice has not been requested or required I'll just cross my fingers and keep my PFD close by the next time we take her out; that may be a while though.