Thru-hulls winterizing

[Brian L.20665]

For first time, I'm leaving my boat in the water over winter. Is there anything different I need to do to protect the thru-hulls? In the past and when on land, I just left the thru-hulls open to drain. With the boat left in the water, I will leave all the thru-hulls closed, but do I need to go to the effort of pouring anti-freeze down hoses to protect that bit of space above the thru-hull valves that will still be full of seawater after winterizing the rest of the systems?

I'm in Annapolis so winter not severe (Ron, what do you do?) Thanks!

Brian

 

[Don S/V ILLusion]

If the Bay doesn't freeze, the water in the thru-hulls PROBABLY won't either but, rather than take the chance, pour antifreeze into the hoses above them while they are open so as to displace any water. Continue pouring as you close the thru-hull(s) to ensure only antifreeze is trapped.
Another option is just remove all hoses so you can easily vacuum out any water in the valve and replace the hoses if you are sure the valves don't leak.

 

[Chuckbear]

Brian, You really need to either get anti-freeze into the hose to the thru-hull itself, make sure it is not diluted by the water in the hose, or pull the hose off, let everything drain out and then re-attach them. Chuck

 

[Ron20324]

I'm in Annapolis so winter not severe (Ron, what do you do?) Thanks! Brian

I put a tee fitting on the water seacock. One side goes on to the filter, the other I put a shutoff valve to attach hose to. several gallons of AF in a bucket, stick the hose in with the thruhull closed, and you can do all the system. Here at Severn House we have 35 bubblers to keep the marina ice-free. Where are you, Brian? You're not Brian H., are you?

 

[Sanfelice]

I take my shop vac and blow all of the lines clear by holding the valve open until I'm sure the valve is clear and shut the valve while it is still blowing.

 

[Ralph Johnstone]

It's Not the Hoses You're Worried About ...............

................ splitting when the water freezes. No big deal because the valves should be closed and you'll see any leaks when you open the thru-hull valves in the spring.

The real problem is that tiny bit of water trapped inside the ball of the closed ball valve. If that freezes and splits the valve body, down goes everything with the first thaw.

I really like Sanfelice's idea of filling the valve ball with air and then closing it. Foolproof as there's no worry about dilution of the anti-freeze.

 

[Brian L.20665]

Thruhulls in winter

Where are you, Brian? You're not Brian H., are you?

Ron, I'm at Mears in Eastport. Mears does bubblers too but not all over, so I may have to move my boat to a bubbled slip. Boat is for sale and broker recommended leaving it in the water since it is easier to show and boats look better on the water than land, of course.

Thanks to everyone for input.

Brian

 

[Bill Roosa]

Spent 5 years (one with ice in the harbor thick enough to walk on) in Harrington Harbor MD. I just closed the valves and never had a problem. Unless your thru hulls are right at the surface the water freezing on the surface will not be a problem. Course if it freezes hard then you have a whole different set of problems and all of them keep the warm deep water flowing around the boat and again you don't have a problem with the thru hulls.

 

[Cayennita]

I lived in Annapolis way up Spa Creek and kept my boat in the water year around and closed all the valves and poured antifreeze in the head and sink lines. Did frostbiting every year and just about every weekend. Never had a problem even though twice the water froze in the creek. Maybe I was lucky. The thru hulls were quite deep.