Leak?

[Specktackler]

Question. I partially filled my 16' Duranautic with water and observed it coming out from the forward keel weep hole. Nothing from strake holes or elsewhere. Does this indicate a leak behind the keel or is there some way water normally flows from inside to the keel and out the weep hole? I suspect a hole but before going any further want to check with those in the know. Thanks!

 

[airshot]

If you only put water on the inside and some is comming out from the outside...it must be a leak. Not unusual to have a hidden leak on a riveted boat. This is why they sell gluvit and other sealers. Normally products like this are the only ways to seal these hidden leaks.

 

[Specktackler]

If you only put water on the inside and some is comming out from the outside...it must be a leak. Not unusual to have a hidden leak on a riveted boat. This is why they sell gluvit and other sealers. Normally products like this are the only ways to seal these hidden leaks.

Thanks! Problem is I have decks and cannot access hull interior. Is it a mistake to seal weep hole and edges of keel? I'm in Fl. so freezing is not an issue.

 

[airshot]

Thanks! Problem is I have decks and cannot access hull interior. Is it a mistake to seal weep hole and edges of keel? I'm in Fl. so freezing is not an issue.

Keels and ribs that are riveted on cant be sealed without a lot of effort. If you dont know exactly where that leak is, just look at your keel and see all the cracks, possible rivet leaks etc, almost impossible to seal completely. Just because the water is comming out the weep hole, that doesnt tell you where the leak is. Sad to say but your not going to fix it without getting to the inside hull unless you can see thru the keel to figure out where rhe leak is !! I am sure all that interior and floors come out....not easy and not fun...but if you want the leak fixed......

 

[DaleH]

Thanks! Problem is I have decks and cannot access hull interior. Is it a mistake to seal weep hole and edges of keel? I'm in Fl. so freezing is not an issue.

Oh boy ... I'd fix it from the INSIDE as you don't know where it is migrating to in order to dump out that keel weep hole.

But I would not just dump water in, in one spot, like filling the hull was done. You might have to remove the floor and try putting water on a keel area only 2' long or such to help identify the area that is weeping. You could even apply clay in areas to make dams to help isolate the damaged area down to a few feet fore and aft. With a floor in your way ... uggghhhh.

Option - Now the epoxies typically used (West System G-Flex 650 or Glu-Vit) do weep and migtrate, so if you turned the hull completely over you could try to get it in to seal the area from the weep hole access. Here's what you'd have to do. Let's pretend the keel weep hole is 2' from the bow portion (of the keel itself, not the hull). Have the hull tipped to one side just a little bit and with the bow down just a little bit, so if you put the epoxy in, it will flow forward and off to that one side. Let's assume that is the right side as looking at the hull upside-down and towards the bow (yes, this is actually the 'port-side of the hull, but stay with me, as you're working on the running bottom).

Now keep in mind if there is a leak ... then epoxy WILL drip out into the boat, but you say there is a floor installed, so you may get any resulting epoxy damage to the inside ... but you will also not know how much is getting into the boat. But suffice to say, if you put in 1/2 a gallon, there is the likelihood that 1/2-gallon could go into the boat! So don't use 1/2 a gallon, which was just a gross example used to make a point! Try a capful and put it into the weep hole to help seal the 'forward right part' of the hull. When dry or cured, tip it to the left and bow down just a little bit and try sealing that "side & forward" area. Cure.

Try again, this time with hull tipped to the right side side just a little bit with the stern down just a little bit so the epoxy dripped in or injected in with a syringe tends to migrate to the right side and away from the forward section you had previously treated. Cure. Repeat to the left side. You might even see epoxy weep out from the keel onto the bottom of the hull, but be aware that that doesn't mean that is a leak that penetrates the hull.

Cure. Then maybe even repeat the steps above. Cure agin. Then try tipping the hull over again and filling it with water, to see if the epoxy may have made a seal???

Product - I personally would NOT use a very thin, vicious epoxy for this like the 2 mentioned above, but one a little closer to being closer to a syrup than that of water. You do want it to flow and migrate - yes - but not be soooooo thin that it just drips through the holes and doesn't fill them. I'd consider buying the epoxy sample kit or the small epoxy/hardener only kit from Raka Epoxy and would likely use a fast cure hardener, so it sets up ... which if that is at or around a hole, should seal it. www.raka.com .

You might even do a 'test' of your epoxy mix against the outboard edge og the keel-to-the-hull to ensure it flows down that edge ... that could give you confidence it will flow when injected inside the keel - where you can't see! And just to throw it out there, I am not sure if Flex-Seal makes a liquid product, but whereas that is likely thicker ... if it flowed good enough for you, that too might seal without making a mess 'inside' the boat.

FWIW I did have to totally remove the entire 10+ long center keel on my saltwater tin to fix it properly, link = Center keel removal & repair – On a SALTwater tin And yes ... it was UGLY under there!

 

[Duro]

Question. I partially filled my 16' Duranautic with water and observed it coming out from the forward keel weep hole. Nothing from strake holes or elsewhere. Does this indicate a leak behind the keel or is there some way water normally flows from inside to the keel and out the weep hole? I suspect a hole but before going any further want to check with those in the know. Thanks!

Hi
I also own a 16' Duranautic SST about 20 years old.
Water can flow through the keel as there are weep holes to allow this.
The two halfs of the hull are joined & welded, then the keel (which is a different grade of extruded aluminum)
is riveted on separately afterwards. So any damage to the keel alone would not cause the boat to leak. If you do indeed
have a leak ,proven with water flowing up in the bildge, You can apply Gluvit or Goop Coat-IT to the rivets from the outside.
I've done this successfully before on 3 boats.
I've replaced the floor in my Duranautic & it is true that the best job is done from inside the hull, BUT I would definitely try this first if I were you.
Good Luck!

 

[Specktackler]

Oh boy ... I'd fix it from the INSIDE as you don't know where it is migrating to in order to dump out that keel weep hole.

But I would not just dump water in, in one spot, like filling the hull was done. You might have to remove the floor and try putting water on a keel area only 2' long or such to help identify the area that is weeping. You could even apply clay in areas to make dams to help isolate the damaged area down to a few feet fore and aft. With a floor in your way ... uggghhhh.

Option - Now the epoxies typically used (West System G-Flex 650 or Glu-Vit) do weep and migtrate, so if you turned the hull completely over you could try to get it in to seal the area from the weep hole access. Here's what you'd have to do. Let's pretend the keel weep hole is 2' from the bow portion (of the keel itself, not the hull). Have the hull tipped to one side just a little bit and with the bow down just a little bit, so if you put the epoxy in, it will flow forward and off to that one side. Let's assume that is the right side as looking at the hull upside-down and towards the bow (yes, this is actually the 'port-side of the hull, but stay with me, as you're working on the running bottom).

Now keep in mind if there is a leak ... then epoxy WILL drip out into the boat, but you say there is a floor installed, so you may get any resulting epoxy damage to the inside ... but you will also not know how much is getting into the boat. But suffice to say, if you put in 1/2 a gallon, there is the likelihood that 1/2-gallon could go into the boat! So don't use 1/2 a gallon, which was just a gross example used to make a point! Try a capful and put it into the weep hole to help seal the 'forward right part' of the hull. When dry or cured, tip it to the left and bow down just a little bit and try sealing that "side & forward" area. Cure.

Try again, this time with hull tipped to the right side side just a little bit with the stern down just a little bit so the epoxy dripped in or injected in with a syringe tends to migrate to the right side and away from the forward section you had previously treated. Cure. Repeat to the left side. You might even see epoxy weep out from the keel onto the bottom of the hull, but be aware that that doesn't mean that is a leak that penetrates the hull.

Cure. Then maybe even repeat the steps above. Cure agin. Then try tipping the hull over again and filling it with water, to see if the epoxy may have made a seal???

Product - I personally would NOT use a very thin, vicious epoxy for this like the 2 mentioned above, but one a little closer to being closer to a syrup than that of water. You do want it to flow and migrate - yes - but not be soooooo thin that it just drips through the holes and doesn't fill them. I'd consider buying the epoxy sample kit or the small epoxy/hardener only kit from Raka Epoxy and would likely use a fast cure hardener, so it sets up ... which if that is at or around a hole, should seal it. www.raka.com .

You might even do a 'test' of your epoxy mix against the outboard edge og the keel-to-the-hull to ensure it flows down that edge ... that could give you confidence it will flow when injected inside the keel - where you can't see! And just to throw it out there, I am not sure if Flex-Seal makes a liquid product, but whereas that is likely thicker ... if it flowed good enough for you, that too might seal without making a mess 'inside' the boat.

FWIW I did have to totally remove the entire 10+ long center keel on my saltwater tin to fix it properly, link = Center keel removal & repair – On a SALTwater tin And yes ... it was UGLY under there!

View attachment 113672

View attachment 113673

Thanks for the detailed reply. While I've been looking for a way to fix it without removing decks have to agree I have a chore in front of me. Thanks again, lot of good info!

 

[Specktackler]

Hi
I also own a 16' Duranautic SST about 20 years old.
Water can flow through the keel as there are weep holes to allow this.
The two halfs of the hull are joined & welded, then the keel (which is a different grade of extruded aluminum)
is riveted on separately afterwards. So any damage to the keel alone would not cause the boat to leak. If you do indeed
have a leak ,proven with water flowing up in the bildge, You can apply Gluvit or Goop Coat-IT to the rivets from the outside.
I've done this successfully before on 3 boats.
I've replaced the floor in my Duranautic & it is true that the best job is done from inside the hull, BUT I would definitely try this first if I were you.
Good Luck!

Thanks Duro. Based on your description of Duranautic construction (mine is a 2004 so around the same vintage as yours) would you agree that, if I put water in the boat and the only place I see it coming out of the hull is through the keel weep hole then apparently the leak is on the weld seam behind the keel?

 

[DaleH]

But ... whereas the keel piece is then riveted on, they can leak too. If you can get to BOTH sides of those rivets, re-buck them.

 

[Specktackler]

But ... whereas the keel piece is then riveted on, they can leak too. If you can get to BOTH sides of those rivets, re-buck them.

So possibly one or more of those keel rivets could be leaking down into the keel piece and not all the way through to the exterior where I'd see it. Gotcha

 

[DaleH]

Yes, exactly. That's why I was thinking that trying to attack by applying the product from the weep hole itself (albeit a pain in the arse to do so ... ) might solve it, at least without removing the floor and other affixed items. If the floor was out, heck you could turn the hull over, block it up some, then fill the keel full of water by the weep hole ... and then crawl under the boat and look for drips!

 

[Duro]

Thanks Duro. Based on your description of Duranautic construction (mine is a 2004 so around the same vintage as yours) would you agree that, if I put water in the boat and the only place I see it coming out of the hull is through the keel weep hole then apparently the leak is on the weld seam behind the keel?

I would say its much more likely to have a bad rivet than a leaky weld-but anything is possible.As others mentioned, its tough to pinpoint the leak most often. Did you do a close inspection for any damaged areas?
inspect transom area carefully also.
When boat is in the water how bad is the water coming in? Saltwater or fresh?

 

[Specktackler]

I would say its much more likely to have a bad rivet than a leaky weld-but anything is possible.As others mentioned, its tough to pinpoint the leak most often. Did you do a close inspection for any damaged areas?
inspect transom area carefully also.
When boat is in the water how bad is the water coming in? Saltwater or fresh?

Yes I've crawled around underneath, see no obvious damage, though the keel is not perfectly tight flat to the hull along it's length but more of a very slight wave, however appears tight at rivets, don't see any dents, etc. Transom which I can see both sides appears fine. Not a lot of water entering but enough that my pumps kick on when accelerating due to water accumulating at stern. Fresh, never been in salt. I think I'll try applying gluvit or flex-spray to the entire keel area from the outside to begin. Then if I have to, pull decks (ugh!) and empty. Thanks

 

[kazzer]

Oh boy ... I'd fix it from the INSIDE as you don't know where it is migrating to in order to dump out that keel weep hole.

But I would not just dump water in, in one spot, like filling the hull was done. You might have to remove the floor and try putting water on a keel area only 2' long or such to help identify the area that is weeping. You could even apply clay in areas to make dams to help isolate the damaged area down to a few feet fore and aft. With a floor in your way ... uggghhhh.

Option - Now the epoxies typically used (West System G-Flex 650 or Glu-Vit) do weep and migtrate, so if you turned the hull completely over you could try to get it in to seal the area from the weep hole access. Here's what you'd have to do. Let's pretend the keel weep hole is 2' from the bow portion (of the keel itself, not the hull). Have the hull tipped to one side just a little bit and with the bow down just a little bit, so if you put the epoxy in, it will flow forward and off to that one side. Let's assume that is the right side as looking at the hull upside-down and towards the bow (yes, this is actually the 'port-side of the hull, but stay with me, as you're working on the running bottom).

Now keep in mind if there is a leak ... then epoxy WILL drip out into the boat, but you say there is a floor installed, so you may get any resulting epoxy damage to the inside ... but you will also not know how much is getting into the boat. But suffice to say, if you put in 1/2 a gallon, there is the likelihood that 1/2-gallon could go into the boat! So don't use 1/2 a gallon, which was just a gross example used to make a point! Try a capful and put it into the weep hole to help seal the 'forward right part' of the hull. When dry or cured, tip it to the left and bow down just a little bit and try sealing that "side & forward" area. Cure.

Try again, this time with hull tipped to the right side side just a little bit with the stern down just a little bit so the epoxy dripped in or injected in with a syringe tends to migrate to the right side and away from the forward section you had previously treated. Cure. Repeat to the left side. You might even see epoxy weep out from the keel onto the bottom of the hull, but be aware that that doesn't mean that is a leak that penetrates the hull.

Cure. Then maybe even repeat the steps above. Cure agin. Then try tipping the hull over again and filling it with water, to see if the epoxy may have made a seal???

Product - I personally would NOT use a very thin, vicious epoxy for this like the 2 mentioned above, but one a little closer to being closer to a syrup than that of water. You do want it to flow and migrate - yes - but not be soooooo thin that it just drips through the holes and doesn't fill them. I'd consider buying the epoxy sample kit or the small epoxy/hardener only kit from Raka Epoxy and would likely use a fast cure hardener, so it sets up ... which if that is at or around a hole, should seal it. www.raka.com .

You might even do a 'test' of your epoxy mix against the outboard edge og the keel-to-the-hull to ensure it flows down that edge ... that could give you confidence it will flow when injected inside the keel - where you can't see! And just to throw it out there, I am not sure if Flex-Seal makes a liquid product, but whereas that is likely thicker ... if it flowed good enough for you, that too might seal without making a mess 'inside' the boat.

FWIW I did have to totally remove the entire 10+ long center keel on my saltwater tin to fix it properly, link = Center keel removal & repair – On a SALTwater tin And yes ... it was UGLY under there!

View attachment 113672

View attachment 113673

I'd suggest a few things.
1. The entire base is a disaster! I'd sand/water blast the entire hull. I'm sure this would expose holes you didn't know existed. see. https://www.amazon.com/Selkie-Press...lpcontext&ref_=fplfs&smid=A26BKM86E438QZ&th=1

2. A coating placed on the inside will be subject to the pressure of the water outside. It would be more secure to coat the outside of the hull, so the water is pushing the coating onto the hull, not off it.

3. You've already ground down the rib metal, weakening it, so I'd fill those holes in with epoxy putty, QUIKALUMINUM EPOXY and drill new holes in between the old ones, so new rivets have a clean and tight hole.

4. I'd be inclined to place 2" wide fiberglass drywall tape along each side of the ribs along the length of the boat, and then coat it, then coat the hull entirely.
https://caswellplating.com/epoxy-gas-tank-sealer.htmlhttps://mud-skipper.com/hull-coatings.html

 

[Duro]

Yes I've crawled around underneath, see no obvious damage, though the keel is not perfectly tight flat to the hull along it's length but more of a very slight wave, however appears tight at rivets, don't see any dents, etc. Transom which I can see both sides appears fine. Not a lot of water entering but enough that my pumps kick on when accelerating due to water accumulating at stern. Fresh, never been in salt. I think I'll try applying gluvit or flex-spray to the entire keel area from the outside to begin. Then if I have to, pull decks (ugh!) and empty. Thanks

That sounds like a plan. How spongy are your floors? Mine were finished after less than 20 years-though garage kept.
If you only have a slight leak you might want to wait before tackling the inside hull sealing. Unless they changed their construction
in 4 years you may be surprised to find floor rot.
Here are before & after pics of my floor replacement. Though they are good boats I am not impressed with some of the under floor construction.
I pulled my boat, pulled plug,drove 1hour, in garage 2 weeks, when floor was removed , there was still enough water in a puddle mid-hull
to support a few live minnows! Also water seeping around floor edges traps water along the flotation- with no way out but evaporation.
They put in flotation to acheive"level flotation" requirements without thinking about drainage!
If you ever do pull the floors do like I did & seal all the rivets at that time & caulk the floor edges.
I have another 14'Duranautic Offshore since the late 70's that has never leaked a drop.
I've talked to friends & many others with these boats through the years & never heard about any faulty welds . Rivets? Yes.

 

[Specktackler]

That sounds like a plan. How spongy are your floors? Mine were finished after less than 20 years-though garage kept.
If you only have a slight leak you might want to wait before tackling the inside hull sealing. Unless they changed their construction
in 4 years you may be surprised to find floor rot.
Here are before & after pics of my floor replacement. Though they are good boats I am not impressed with some of the under floor construction.
I pulled my boat, pulled plug,drove 1hour, in garage 2 weeks, when floor was removed , there was still enough water in a puddle mid-hull
to support a few live minnows! Also water seeping around floor edges traps water along the flotation- with no way out but evaporation.
They put in flotation to acheive"level flotation" requirements without thinking about drainage!
If you ever do pull the floors do like I did & seal all the rivets at that time & caulk the floor edges.
I have another 14'Duranautic Offshore since the late 70's that has never leaked a drop.
I've talked to friends & many others with these boats through the years & never heard about any faulty welds . Rivets? Yes.

I experienced floor rot in only one location, forward, several years ago. I removed and replaced it with plywood encapsulated in epoxy resin. I then caulked where the deck met the hull and painted it with Tuff coat. No problems since. I also through bolt-mounted pedestal seats, hence my reluctance to remove everything. Going to seal from below and go from there. Oh yeah, I also added a forward deck with a hatch over the front bench seat. I had a pedestal seat mounted there but have since removed it and sealed the base with a blank hatch cover. That's where the trolling motor battery and onboard charger live. The starboard side storage box houses the outboard battery. 16-gallon fuel tank behind the rear pedestal seat. The yellow hull (one part epoxy) works here in Flor a Duh.

 

[Duro]

Specktackler, your boat looks great! I like the front deck that you added . I also added a front deck with storage hatch to mine but lower(bottom of seat) with it open at the front for anchor storage. Just wanted more free board. I also used marine ply with epoxy , paint then vinyl like original.The original front floor was a crotch killer & way too low for stepping in for me.
I like your Tuff Coat idea also.Looks good.
My starting battery & switch is in starboard transom box (custom) & trolling battery in starboard front storage box where your starting batt is. I use the port livewell box as storage also.Yes getting to the inside hull of these boats is a major pain & only done as last resort IMO.
My boat leaked slightly for years before I replaced floors & resealed rivets. 100% dry now.

 

[Specktackler]

Specktackler, your boat looks great! I like the front deck that you added . I also added a front deck with storage hatch to mine but lower(bottom of seat) with it open at the front for anchor storage. Just wanted more free board. I also used marine ply with epoxy , paint then vinyl like original.The original front floor was a crotch killer & way too low for stepping in for me.
I like your Tuff Coat idea also.Looks good.
My starting battery & switch is in starboard transom box (custom) & trolling battery in starboard front storage box where your starting batt is. I use the port livewell box as storage also.Yes getting to the inside hull of these boats is a major pain & only done as last resort IMO.
My boat leaked slightly for years before I replaced floors & resealed rivets. 100% dry now.

Thanks Duro. Where are you in Ontario? When I lived in Pittsburgh and later south Jersey I did a lot of fishing in your province. East and north of Toronto as well as flying out of Cochrane.

 

[RaisedByWolves]

If you only put water on the inside and some is comming out from the outside...it must be a leak. Not unusual to have a hidden leak on a riveted boat. This is why they sell gluvit and other sealers. Normally products like this are the only ways to seal these hidden leaks.

Not necessarily.

Hes in FLA and filling the boat with cold water will cause condensation to form on the bottom.

This drove me nuts checking my hull until I figured out what was happening.

 

[airshot]

Not necessarily.

Hes in FLA and filling the boat with cold water will cause condensation to form on the bottom.

This drove me nuts checking my hull until I figured out what was happening.

I was understanding that he had a steady drip comming out, probably should not have assumed that...due to humidity in FL. condensation could be an issue !