Freezing Water and Marelon Thru Hulls

[philwsailz]

I am in Oklahoma. We do not get super hard freezes usually, but last year my Catalina C-22 sat in a cradle of ice 5" thick for about three weeks. I am on a fresh water lake and in a protected cove, so the ice just froze, no heaving, no movement laterally....

I am going to be launching my new-to-me Catalina C-27 in the spring, and I am thinking about thru hulls. Will a Forespare Marelon thru-hull and seacock freeze and crack open in a situaation similar to last year where we had thick ice and low temps for a long, (for Oklahoma) spell?

Who out there wet-slips year-round, what are your sea-cocks? Who has had them fail and why? Outside of winterizing water and plumbing systems, what do you do to assure that you don't inadvertantly sink a boat due to a freeze-broken seacock, (ball valve)?

 

[Snotter]

I live aboard my boat in north Alabama. Last year the harbor I'm in froze over; however, there was a boundary of water a few inches thick between my hull and the ice. I never winterize; but, the boat is heated on the inside. The engine room is kept around 60 degrees. The glass skin of the hull got down to dang near 32 degrees last winter. Since the through-hulls stick up into the warm air of the engine room, they don't freeze.

 

[gpd955]

My boat is in year round (except this year since I just bought her and need to do some maintenance) and none of our group has had any failures of the Marelon seacocks. We are in Atlantic City, NJ and while the harbor freezes at times, the marina has bubblers.

When I winterize the systems I pull all of the hoses off and put anti-freeze directly into the seacock, then reattach the hoses. Then I finish winterizing the systems. Seems to work for me. I never kept the boat heated in the winter, unless we were on board, since the old boat had an A4 and I always feared fume build up while we were away but I probably will keep it heated next winter when she stays in the water.

I've had both plastic and bronze and neither gave me a problem when I winterized them and made sure that the anti-freeze got into the valve. Since I always did it that way, I have no idea if they would have failed if I didn't.

 

[Ross]

freezing water will crack granite, split steel pipe, crack engine blocks, plastic plumbing parts. It is best just to make certain that the things you want to keep don't freeze.

 

[DianaOfBurlington]

Marelon through-hulls are wonderful; but as Ross says ice will break anything. Water in general is the strongest force known to man.

If you have any doubt, heat one up (gently), separate the 5200 and remove it.

If you have the kind of t-hulls that can be dismantled in place, try taking one apart and checking for damages. I would *assume* it's all right, but don't go by what you'd like to be true. For $80-100 you can replace any one of them. That may be the safest course.

(DO NOT replace one using ANYTHING ELSE but 5200. Please.)

In any case remember to keep near each through-hull TWO pieces of the corresponding wooden plug. My rule is that within 10 seconds of discovering a leak you should be able to identify, get access to, and turn off or plug a leaking through-hull. If not, make it so.

 

[Roger Long]

(DO NOT replace one using ANYTHING ELSE but 5200. Please.)

Remember also that this is a forum of opinion and not all of it is expert. Don't use anything but 5200 if you are working on his boat but seek additional advice if working on your own.

 

[Scott T-Bird]

I think materials make a difference but ice isn't always all that destructive. As long as there is room for expansion, ice will do no damage. For instance, ice trays don't get damaged and they can be pretty flimsy. I use plastic jugs filled with water as weights to hold down tarps in the winter ... the flimsy plastic expands with the ice and the caps never have any damage. I leave valves open and lubricated and can't see why there is any reason for alarm over ice. If the boat is in the water, there is no reason to suspect any damage to valves even if the hull does form some ice around it. In relatively thin layers of ice (less than a foot thick on the water surface, say), the expansion will always be away from the rigid surface of the hull. In my mind, there is never even any cause for alarm when incidental water is left in the water tanks or even the plastic pipes. When there is room for expansion, nothing is going to happen. On the other hand, an engine block filled with water is going to be toast in the spring. Concrete that absorbs small amounts of water will spall ... it is all because there is no room for expansion in rigid materials.

 

[Ross]

Experience has had me replace condensate lines from attic air conditioners. The pipes didn't drain completely and froze at a low point and cracked and leaked condensate on the living room ceiling the following summer. The home owner thought that he had a roof leak and spent many dollars chasing that. Plastic pipe breaks, copper plumbing will burst or even push the soldered fittings apart. There was a power failure one very cold winter and the hot water space heating system froze and broke several elbows at our church. Even when there seems to be room for the ice to expand it sometimes doesn't work out as we would expect. I posted a picture here one time of a tin can with the bottom pushed out. It was sitting on wood and filled with rain water when it froze it did so from the top down so all of the expansion was confined by the plug of ice at the top. an examination of ice in an ice cube tray will show little peaks on each cube, the expansion is up in that case.