If it's not porosity what is it?

[John3]

My boat is a 23 ft, 1967 Dorsett Cabin Cruiser, on a trailer, stored at home. I've owned it since 1970. It has a leak that's driving me nuts. I've patched everything i can find, filled every scrape and scratch on the hull but it still leaks.
Yesterday I took it out to see if I'd fixed the leak. I removed the floor in the cabin, exposing the inner hull surface. The 1st thing I noticed was water oozing in through the resin in an area I had patched. After a few minutes water came through the scupper holes at the aft cabin wall, filling the trough on the starboard side where the keel rises above the inner hull surface. After about 2 hours the water was about 1 1/2 inches deep.
The only explanation I can think of is porosity may have developed over the years, especially since I saw water coming through what appears to be solid resin.
Re gel coating doesn't seem practical, I'm looking for some sort of heavy duty coating for the outer hull surface. Something thicker than epoxy paint.
Any suggestions????

 

[Woodonglass]

Uhmm, I'd advise posting some pics. When you say you've patched everything, what exactly does that mean and how and where are these patches? What materials were used. Were they done on the inside or outside of the hull or both? Why were they done? Were there holes? Cracks? What? The more details you provide the better we can help troubleshoot the issue. Polyester Resin and Epoxy resin are not porous enuf to allow that kind of water penetration that quickly.

 

[John3]

If I could figure out how to reduce the picture size this tablet takes I'd post a couple.
The stuff I did isn't leaking badly. A few drops every couple of minutes and I can probably stop it completely with resin. It's inside the cabin where the keel rises above the hull. I cleaned it up, dried it blowing warm air from a heater for 4 days, then applied Sea Goin Poxy Putty filling in the voids and forming a smooth radius at the inside corner. Then I applied 3 layers of fiberglass cloth using Bondo 2 part resin.
I haven't been able to get to the area where the real leak is located and haven't done anything to fix it yet. It's just aft of the cabin under the gas tank floor in the cockpit. To get to it I'd have to remove the tank and then cut out the underlying floor. I'd rather work on the outside of the hull, it's easier to get at and that's where the water is coming from. The problem is, I've examined the outside of the hull in the area in question and can't find any damage. Which is why I think it is porosity. So I'm considering applying a barrier coating to the gel coat in that area And see if it stops or at least reduces the leakage.
Any better ideas?

 

[John3]

I just re read my post. It sounds like i only examined part of the outside of the hull below the waterline. I've examined every square inch of the hull. If there's a Crack, it's invisible.

 

[redneck joe]

not the expert here, but a properly applied bottom paint should work?

 

[Rickmerrill]

Since the "upgrade" the upload feature, well not so much. The recommended way is to get a free photobucket account, upload there, copy the IMG link of the pic and post it directly into the text of your post. You might still get an error message, just refresh and check, 9 times out of 10 it works.

 

[Woodonglass]

Again, based on the amount of water coming in, it's NOT porosity. NO resin of any kind allows water penetration to the extent that you are stating. None!!!!

 

[glenn property of pam]

boats are constructed with different sections under the deck so a leak anywhere in the section can come out anywhere it can find a hole. My boat leaked in the middle of a stringer 10' from the transom yet the water was entering at a hole in the transom. There's no reason the water has to enter the same area where you are seeing it.

 

[studioq]

There's no reason the water has to enter the same area where you are seeing it.

Yep... Hydrostatic pressure can be a fumy thing. Water can be coming in anywhere and leak several feet away.

 

[jigngrub]

Painting a boat to stop leaks is futile, the fix will only be temporary if it works at all.

It would be interesting to see pics of the inside of your hull.

On an old boat like that with those kinds of problems you may want to consider overlaying the entire inside of the hull below the waterline with 1708 and resin.

 

[studioq]

On an old boat like that with those kinds of problems you may want to consider overlaying the entire inside of the hull below the waterline with 1708 and resin.

+1 for that. This is exactly what I'm doing on my hull and it's only 22 years old..