Leak in aluminum boat

[iggyw1]

Hi again,
I wrote in the past about a water leak problem I was having in my aluminum boat, and because I have some new information on the situation, I figured I would start a new thread here. I finally found the leak. It is in the very center of the boat along the back wall, right where the transom meets the floor, and right in line with the center of the motor. I put the boat in the water and it did not leak at all until I got in the boat and sat on the bench seat at the rear of the boat. I realize this is due to the added "pressure" once I got in the boat. It does not leak real bad at all, but the water is seeping in.
I really believe that the right way to repair this is to re-rivet the thing. There are rivets in the floor through what I refer as a corner molding that connects the stern to the floor of the boat. But short of replacing rivets which I cannot do myself, I am curious as to what the general opinion is if I can clean it up really good and seal the area inside/outside with a good sealer. I heard about a sealer called Gluvit that is suppose to be good for this purpose. Anyone use it that could recommend it? Any other sealers recommended?
Also, the leak is worse at WOT of the 35 H.P. motor on the stern, yet, the stern is solid and does not appear to be moving around at all upon my inspections of it when on land I appreciate any thoughts on this and I thank you in advance.

 

[Chris1956]

There are solid pop rivets in various sizes. Those may seal the leak, after you drill out the old rivets. The other choice (I am not an expert on aluminum) is to buck the rivets to reseal them. Is there any damage on the mating surfaces of the plates, or are the rivets just loose?

 

[matt167]

There is also a torch wax that will seal rivits and gluvit which will bandaid the leaks ( good idea regardless if you have it down far enough to do it )

 

[iggyw1]

There are solid pop rivets in various sizes. Those may seal the leak, after you drill out the old rivets. The other choice (I am not an expert on aluminum) is to buck the rivets to reseal them. Is there any damage on the mating surfaces of the plates, or are the rivets just loose?

Just looking at it without doing any wire brushing or scaping at all, I do not see any damage (dent, knicks or bumps) nor do I even see a rivet or two that looks loose at all. Everything looks real good except the water seeping in when I board the boat. There is a small opening somewhere along the rear most seam where the floor and the transom meet right in line with the center of the motor, so I was wondering if i am just wasting my time if I cleant it up , wire brush and use a sealer. Thanks for your input.

 

[iggyw1]

There is also a torch wax that will seal rivits and gluvit which will bandaid the leaks ( good idea regardless if you have it down far enough to do it )

I am interested in more info about the torch wax. Can you give me anything more about this product? Just a brand name maybe? Thank you.

 

[matt167]

Cabelas brands it. It’s a plastic wax that melts into rivits

 

[airshot]

How much effort do you want to put into this project ?? Are the rivets in an area where you can access top and bottom of the rivet ? Re- bucking is not that hard if you have acess to the rivet and a friend on the other side of the rivet. If you do that, it should be finished with gluvit on the inside only. If you choose an easier route, there is a product called " leak stopper" from tractor supply or home depot. It is a clear roof sealant and it works very well. I used it on my Jon boat over 8 years back and still no leaks ! Comes in a can,, can be brushed on like thick paint. Can be painted over with enamals. Probably other sealants out there just as good if you look around. So...how much work/ effort do you want to put into this ?

 

[iggyw1]

How much effort do you want to put into this project ?? Are the rivets in an area where you can access top and bottom of the rivet ? Re- bucking is not that hard if you have acess to the rivet and a friend on the other side of the rivet. If you do that, it should be finished with gluvit on the inside only. If you choose an easier route, there is a product called " leak stopper" from tractor supply or home depot. It is a clear roof sealant and it works very well. I used it on my Jon boat over 8 years back and still no leaks ! Comes in a can,, can be brushed on like thick paint. Can be painted over with enamals. Probably other sealants out there just as good if you look around. So...how much work/ effort do you want to put into this ?

 

[iggyw1]

Thanks. I will look into the leak stopper art Home Depot. I can try re-bucking the rivets that I can get to. There is one support bracket supporting the transom right in the center that I cannot get to the rivets unless I remove that support bracket by removing all of the rivets on it going around the base of it thru the floor and up the sides of it going thru the transom. I do not think I will get into that, so I am determined to put a band aid on it to try to stop the leak first. I will definitely do the rivets along the rest of the transom though. Thanks.

 

[cyclops222]

Your transom leak is actually the place where the folded over transom is riveted to the floor ? If yes ? Then a person inside the boat with the HEAVY Block of steel is required. And the person under the boat swings a hammer. Less tiring that way. I would use a NON rusting very soft wire wheel to run along the rivet head lines. Inside & outside. of the rivet lines. Then apply the paint on sealant.

Edit The inside block of steel. MUST NOT touch more than 2 rivets at a time. 1 at a time is best.. NO gorillas are allowed to swing the hammer !! A couple of pounds of hammer swing does it every time. The sealant will really seal your leaky rivets.

 

[iggyw1]

Your transom leak is actually the place where the folded over transom is riveted to the floor ? If yes ? Then a person inside the boat with the HEAVY Block of steel is required. And the person under the boat swings a hammer. Less tiring that way. I would use a NON rusting very soft wire wheel to run along the rivet head lines. Inside & outside. of the rivet lines. Then apply the paint on sealant.

Edit The inside block of steel. MUST NOT touch more than 2 rivets at a time. 1 at a time is best.. NO gorillas are allowed to swing the hammer !! A couple of pounds of hammer swing does it every time. The sealant will really seal your leaky rivets.

I am going to do this hopefully tomorrow or Wednesday when I have a buddy available to give me a hand with it. The only problem I have with this is that the leak actually appears to be coming from the rivets that are inside a brace that is going up the stern at an angle from the floor. Looks like the floor rivets that are leaking inside this brace. It is hollow however, so I may be able to dig up something that can be held down inside of this brace to place on top of the rivets in the floor from the inside. I can then pour some of the sealant that I ordered down into this brace and hope it seals it. I ordered some Flex seal yesterday and it should be at my house today. Hope that works as advertised.
NOTE: I will report the results when I get 'er done in this thread. Thanks for everyone's input.

 

[cyclops222]

We put on those CHEAP Latex Rubber gloves. Put a tube of outdoor Silicone Rubber inthe caulk gun. WE did the smearing of the caulking on the line of rivet heads on the water sides first. Then did the inside lines last. No reason.
Lots of Aluminum boats running decades later............ DO NOT makr any big blobs !!!!!! the Silicone right at the round thin edge is only what needs any Silicone. NO time is needed to waste on each rivet head. APPLY ... and smear off excess. Done Very satisfying result.
We never did many block of steel & hammer work. Unless there was severe loose rivets .

 

[JASinIL2006]

I imagine re-bucking the rivets is the best fix, but I can say I've used Gluvit in a similar situation and that repair has held up in excess of 12-13 years. Since Gluvit is an epoxy, UV light will degrade it, so you do need to cover it with a coat of paint.

 

[airshot]

We put on those CHEAP Latex Rubber gloves. Put a tube of outdoor Silicone Rubber inthe caulk gun. WE did the smearing of the caulking on the line of rivet heads on the water sides first. Then did the inside lines last. No reason.
Lots of Aluminum boats running decades later............ DO NOT makr any big blobs !!!!!! the Silicone right at the round thin edge is only what needs any Silicone. NO time is needed to waste on each rivet head. APPLY ... and smear off excess. Done Very satisfying result.
We never did many block of steel & hammer work. Unless there was severe loose rivets .

No disrespect intended, but I would never use silicone. Reason being is that nothing else will stick to that surface when a future repair is needed for that area. In my younger days we used silicone because there was no real history about the stuff. Today there are many better, longer lasting sealers without the silicone after effects. Just my opinion....

 

[iggyw1]

Well guys, I have got some results here for my repair of my leak. I promised I would report my results. I used Flex Seal in a spray can. I got two cans of it from an online store for the price of one can, so I figured I would try it out. I cleaned the seam along the inside and the outside of the boat really good. I sprayed two layers of the Flex Seal on the inside and the outside, allowing 12 hrs. between coats. Took the boat out today, and no leak! I took the boat out without using my main motor because where the leak was at (along the bottom of the transom) I removed my batteries, fuel tanks and even the bilge pump so I can seal the whole seam. The items were removed previous to me spraying the entire seam with the flex Seal ,so I left it all out and just used my electric trolling motor today. I made sure things were very dry today after I took it to the lake, and sprayed an additional coat on the seam inside and out. I will take it out again in two more days with the main motor WOT to see if it really took care of my leak, as when it leaked, it was a lot worse at WOT with the gas motor pushing against the transom. Time will tell. Will post a final follow up here after that trip to the lake. Thanks again for all of your input to help me out. i appreciate it.

 

[airshot]

From my research it is not long lasting and can be very difficult to remove. Hope it works for you.

 

[iggyw1]

Final update 07-03-2024. I took the boat out and there are still a few very small leaks but not the rivets that I sprayed with the Flex Seal. There are some small leaks at some rivets that are nowhere near the stern, but they look like the rivets that are holding the main aluminum strip running right down the middle of the boat, the entire length of the boat. I am thinking this is the keel?? Well, there are some very small leaks on these four rivets that are located between the rear bench seat and the stern. I was out for a few hours on the lake today, and had only enough water in the boat that i used the sponge in my boat only once to mop it up. Did not have to ring it out and re-sop the water up. I have enough Flex seal left in a can that I will be spraying these four rivets with tomorrow when everything is very dry (did not want to take a chance on it today). I think my problem is solved, now I hope the Flex Seal lasts for a few seasons at least if not longer.

 

[Chris1956]

Phil Swift would be proud!