Wet Leak Seepage Fix for a Thru Hull?

[sdowney717]

One of my engine thru hulls has developed a tiny weeping leak.
It is occurring between backing plate and hull bottom.

It is so slow that dry it up and within 30 seconds a tiny tiny tiny tiny amount of water will form.
over a long time it does collect some water.

So I was wondering if there was some goopy stuff that you can force into the interface area to dry up this leak without pulling the boat.

[Vasco]

try wrapping a thin fiberglas thread dipped in 5200 or some other caulk around the backing plate so that it goes under the backing plate.

[AnchorageGuy]

Obviously the thru-hull is not sealed and water leaks don't just go away. Anything you do short of pulling the boat and re-bedding will only be a band-aid and putting any kind of epoxy or whatever on the thru hull will only make a correct repair harder when you decide to do it right. Small leaks get bigger in time unless they are repaired. Chuck

[Cheechako]

Some sealants can be applied wet. You could snorkel down and create a fillet around the thru hull perimeter with your finger, that way the pressure is forcing it into the joint. You should haul and do properly soon though....

[Jim Cate]

Splash Zone epoxy will stick and cure under water, and would likely cure the symptom.

However, you are risking possible sinking or at least water damage if your band-aid should fail. Further, it could be a failing through hull fitting, not just bad sealant, with the possibility of it suddenly becoming a major leak. IMO, you should go ahead and slip the boat and do it right.

Cheers,

Jim

[bobconnie]

My Daddy told me ! Fix it Once right ! Lots of boats have sunk from " Lets Patch it for Now !!" and fix it right later!! Fixin it right has saved my bacon lots of times in the last 50 plus years at sea. Just my 2 cents

[zeehag]

you can replace thru hulls in water--just takes skill. dont have to haul--but it does need to be replaced--you do not want it getting worse. will happen. i had one replaced in water on my ericson when i first bought her. had a film of water on hull just inside the fitting---any good diver can do the work.

[Noname]

Can you tighten the locking nut a bit to stop the leak until repair can be done??

[sdowney717]

Ok, I spent time looking at this very carefully yesterday.
And found it is seeping from the threads where the valve screws on not from the backing plate.

I figure if I do this in the water, I can unscrew it and coat with some teflon paste on the threads while putting a heavy lead weight and rubber gasket on top of the pipe to keep water out, or buy a pipe cap. It has been about 2 years since I had boat out and had this thing in my hands so it is likely still ok. It is a scoop type bronze pickup oval shaped thing on the bottom and I think it is 1.5 inch thread.

I kept wondering how it could be leaking as I know I sealed it very well, so at least I know now what is really happening with it.

[AnchorageGuy]

That can work but be careful. In loosening or tighten the valve on the thru-hull, the entire thing can spin loose. Just proceed carefully and watch for any slight movement while you are loosening the valve. If the thru-hull is well bedded with something like 5200 you should not have a problem. Chuck

[senormechanico]

How about putting a piece of plastic wrap over the outside to stop water ingress while you work on the inside?

[neilpride]

Cored hull or solid?

[Tellie]

Just a bit of advice and it's worth the price you pay. I would not attempt an in the water thru-hull change out on an existing thru hull that leaks. A small leak can be as simple a fix as replacing with new sealant, it can also be an indication the the hull material around the thru-hull has damage as well. Pulling out a thru-hull in this state can result in a much larger hole than anticipated being left behind. If circumstances dictate, I'd attempt a temporary fix with a sealant now without removing the thru hull and as suggested several times above, do it right and pull the boat. If one thru hull is showing signs of leaking there's a good chance the other thru hulls should be pulled and re-bedded as well.

[delmarrey]

I just love some of these threads!

[Cheechako]

Originally Posted by sdowney717

Ok, I spent time looking at this very carefully yesterday.
And found it is seeping from the threads where the valve screws on not from the backing plate.

I figure if I do this in the water, I can unscrew it and coat with some teflon paste on the threads while putting a heavy lead weight and rubber gasket on top of the pipe to keep water out, or buy a pipe cap. It has been about 2 years since I had boat out and had this thing in my hands so it is likely still ok. It is a scoop type bronze pickup oval shaped thing on the bottom and I think it is 1.5 inch thread.

I kept wondering how it could be leaking as I know I sealed it very well, so at least I know now what is really happening with it.

The force of the water coming in a thru hull is amazing, a lead weight and rubber gasket will not stop it. You will need something from the outside. Trouble is, maybe the threads on the thru hull fitting are cracked and that's why it's leaking... it's a little risky. BTW, seems to me the threads shouldnt be even seeing any water...? The scoop should be sealed before it gets to the threads. Is it possible that the boatyard can lift the boat leaving it in the slings at the end of the day while you do this? Otherwise...Buy some tapered wood plugs and make sure the bilge pump is operating well....