Keep ice out of PVC Gate Valves

[eugenesdream24]

Hey everyone, I am in a pretty tough spot this winter as my boat had to stay in the water while I am doing a motor swap out. All of my winterizing has been completed awhile back now, but I am still worried about the dilemma of 2 PVC gate valves under my galley and head sinks that will not close. So there is a bit of water freely flowing through. The canal I am on is getting pretty slushed up and will probably freeze over pretty good by the end of this month going into March.

I have a heater on board to keep the temperature inside the cabin up to avoid any frost or freezing temperatures, but I wanted to post my situation to see if anyone has any easy fixes or tricks to keep these gate valves from getting ice in them and cracking or splitting completely. A friend of mine recommended pipe warmers to avoid any freezing but I think that has a whole other set of risks.

I am putting thousands into her over this winter putting in a new motor, winches, you name it. So it is a nightmare to imagine an old gate valve blowing out and destroying all my hard work.

I know I should have upgraded them before the winter, and come spring when she gets taken out for a quick bottom paint and clean up I will do so before she is re-launched. With all likeliness I am actually going to permanently seal them. But til then, any help or guidance is greatly appreciated to give me a little piece of mind when I sleep at night that she won't be halfway under water in the morning.

Both valves are identical and are from the sink drains:

 

[JK_Boston_Catalina310]

PVC gate valves? That doesn't sound right. Why won't they close?

I would be very leery of having a boat in the water for the winter without being able to close my through-hulls.

Do you have any photos?

 

[DougM]

PVC gate valves? That doesn't sound right. Why won't they close?

I would be very leery of having a boat in the water for the winter without being able to close my through-hulls.

Do you have any photos?

I hope that the valves are ball valves and not gate valves. Even if they are closed I would think you would run a high risk of cracking them.
When you replace, make sure they are bronze and not brass, if you don't sink first...

 

[eugenesdream24]

PVC gate valves? That doesn't sound right. Why won't they close?

I would be very leery of having a boat in the water for the winter without being able to close my through-hulls.

Do you have any photos?

Picture is here, and added to the original post. Any thoughts are appreciated.

 

[kito]

I got to say, that looks scary to me. I wouldn't want any pvc on my thru hulls especially below the water line. My PO had pvc hose nipples on brass inline ball valves that I ripped out. I replaced all with bronze flanged seacocks and bronze tailpipes where needed. Just my opinion but I wouldn't use those valves....especially pvc gate valves. Any reason why you chose pvc gate valves over ball valves?

 

[eugenesdream24]

I got to say, that looks scary to me. I wouldn't want any pvc on my thru hulls especially below the water line. My PO had pvc hose nipples on brass inline ball valves that I ripped out. I replaced all with bronze flanged seacocks and bronze tailpipes where needed. Just my opinion but I wouldn't use those valves....especially pvc gate valves. Any reason why you chose pvc gate valves over ball valves?

I would never choose them, they were from the original owner. So it is an inheritance situation that I should not have neglected. Now I am just hoping nothing bad happens this winter.

 

[Apex]

Don't think he "CHOSE" those.
Is there a means to put a barrier exterior to the thru hull as a "patch" There are some different types of emergency plugs that may be used in conjuction with the existing valve. Your concern is valid I think. As is having an onboard heater left unattended.

 

[Sanfelice]

You didn't mention if your slip is bubbled. If so , in theory you shouldn't have ice getting into valve. Unfortunately , theories are theories. Since you have 110 you might consider electric pipe heater wire.

http://www.lowes.com/Search=wire+he...logId=10051&N=0&newSearch=true&Ntt=wire+heat#!

 

[eugenesdream24]

You didn't mention if your slip is bubbled. If so , in theory you shouldn't have ice getting into valve. Unfortunately , theories are theories. Since you have 110 you might consider electric pipe heater wire.

http://www.lowes.com/Search=wire+he...logId=10051&N=0&newSearch=true&Ntt=wire+heat#!

I'm hoping the de-icer bubbler will do it, but I've been told I should take extra efforts just in case.

 

[jibes138]

Here's a suggestion. Build a tube around the whole mess higher than the water line. Water will only come in up to the water line so if you keep it contained to a small volume your boat won't sink. Take off the hose slide a length of pipe over the valve and bond it to the hull maybe with fiberglass cloth and epoxy or perhaps an adhesive caulk will work. As long as the pipe is higher than the water line any leak will be contained.
Also get an emergency bilge pump like maybe a submersible sump pump as a last fail safe. Put it maybe at floor level and run the hose overboard. If the boat starts to sink this will keep you floating until it can be dealt with.

 

[kito]

My bad. They look fairly new. I understand your concern. Really don't have an answer other than hauling out and replacing for peace of mind. If I had someone plug the thru hull from the outside, I would still wonder if it was done correctly. As is, you may be better off keeping those plastic valves open anyway.

 

[Stu Jackson]

I just rebuilt two of those very same valves. Mine are white, same thing. The reason one leaked was old O rings, which I replaced at a hardware store. These valves are on our domestic water pump intake header to choose between which water tank to use.

ITWMB, I'd leave them closed if you can close them, but you said you couldn't. Dave's idea is a good one. A couple of big PVC pipes glued to the hull should work. Finally, a use for 5200!

Just kidding, but some epoxy should bond it well enough and still be able to be removed in the spring.

Good luck.

If you do consider heat trace, be very, very careful. Heat trace is not usually recommended for profession plastic pipe, and these valves are far from the quality of that material. Research it well before you go that route.

 

[Don S/V ILLusion]

Is here some reason you can't take it out?

Heaters can't possibly compensate for the heat loss around the hull. Bubblers won't change that. Freezing is inevitable. I understand you don't want to haul but if I was your insurance underwriter, I'd tell you to start praying.

 

[kito]

I only said to keep those plastic valves open because they will act like freeze plugs if closed and guess what's going to crack first? No sense to dead head the water at a plastic valve imo. I would rather have my hose connected directly to the thru hull. On the other hand, if the water is froze then there is no risk of sinking your boat

 

[Don S/V ILLusion]

. On the other hand, if the water is froze then there is no risk of sinking your boat

Right up until the minute the ice thaws.

 

[just lucky]

Why does it have to stay in the water during the engine swap?

 

[Gunni]

Your boat is at risk of sinking.

Three possible options:

1. Fill the standpipe above with 100% glycol, thaw the valve, open and displace water with antifreeze. If valve is cracked or it continues to leak move to #2.
2. Haul the boat immediately at your closest yard, dry store.
3. Pay a diver to drive a plug into the thru-hull from outside the boat.

 

[gettinthere]

Agree on hiring a diver to stuff bungs into the thru hulls from below. You might get some of the 2 part paste that will hardsn underwater and use that around the bung before insertion to complete the seal. Have the diver do a 'dry' fit first to mark the bung and then apply the epoxy paste all around the bung above and below the mark.

Is glycol heavier than water? If you pour antifreeze in from above waterline, will it sink down to the valve? If so, that would also help. If it does not, perhaps rock salt?

 

[woodster]

Agree on hiring a diver to stuff bungs into the thru hulls from below. You might get some of the 2 part paste that will hardsn underwater and use that around the bung before insertion to complete the seal. Have the diver do a 'dry' fit first to mark the bung and then apply the epoxy paste all around the bung above and below the mark.

Is glycol heavier than water? If you pour antifreeze in from above waterline, will it sink down to the valve? If so, that would also help. If it does not, perhaps rock salt?

don't know if salt will help...salt water freezes at 28.4 degrees and that only gives you a 4 degree edge over fresh water ...but i have heard some old salts say put rock salt in the bilge

 

[kito]

Specific gravity of sea water is 1.025 (1.0 for fresh water) and glycol is 1.1. Unless the thru hull is plugged, what would keep the glycol from going bye bye? Probably a good solution though. Hire a diver (that knows what he's doing) to plug the 2 thru hulls and pour some glycol down the drain. I know I would sleep better at night.