# Sealing cap to hull....



## dlpanadero (Mar 9, 2016)

what do you mean by water coming into the boat? Like into the cockpit area? Are you sure it’s coming in through the cap/hull joint? That rubber seal you’re pointing at (as far as I know) is just to protect the thin fiberglass flange from breaking when it bumps into things. Those gaps shouldn’t be responsible for letting water into the boat. There should be a bunch of glue/putty up under your gunwales where the cap is actually bonded to the hull. No water should ever be able to come through this joint.


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## DuckNut (Apr 3, 2009)

This happens all the time. The builder cuts corners and slaps a rail over it so it can't be seen.

Marine caulking is fine. If you pack it with epoxy the cap will never come off should the need arise.


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## FlyBy (Jul 12, 2013)

DuckNut said:


> This happens all the time. The builder cuts corners and slaps a rail over it so it can't be seen.
> 
> Marine caulking is fine. If you pack it with epoxy the cap will never come off should the need arise.


Yep, caulk it. That's what I did in the same situation.


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## topnative2 (Feb 22, 2009)

pipe insulation first to seal the gap


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## TroutNreds12 (Jan 4, 2016)

The cap should never be able to be removed if done properly. That all should have been back filled after deck was glued. Very time consuming and companies just cut corners sucks


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## Steve_Mevers (Feb 8, 2013)

When I owned a 17T it leaked badly at the cap / hull seam, I removed the entire rub rail and used 3m 5200 to seal it, then reinstalled the rub rail. Good luck


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## JC Designs (Apr 5, 2020)

I would caulk as mentioned with a marine sealant. 5200, 4200, etc... thickened resin/epoxy probably won’t get a good bond because of the area being dirty and access being limited to properly prep.


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## Dalecityusa (Sep 14, 2016)

jackson man said:


> Flex Seal tape! Sorry, I couldn't resist!


😂😂😂


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## Dalecityusa (Sep 14, 2016)

Awesome y’all great ! Will use marine adhesive


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## Dalecityusa (Sep 14, 2016)

Steve_Mevers said:


> When I owned a 17T it leaked badly at the cap / hull seam, I removed the entire rub rail and used 3m 5200 to seal it, then reinstalled the rub rail. Good luck


When you reinstalled rub rail did you use the same holes or did you fill old holes and make new ones ? Did u get a new rub rail or re use ?


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## Steve_Mevers (Feb 8, 2013)

Dalecityusa said:


> When you reinstalled rub rail did you use the same holes or did you fill old holes and make new ones ? Did u get a new rub rail or re use ?





Dalecityusa said:


> When you reinstalled rub rail did you use the same holes or did you fill old holes and make new ones ? Did u get a new rub rail or re use ?


 It has been several years ago, but I am pretty sure I used the same holes. I had several gaps around the boat and that and the deck drains were the source of my water leaks.


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## Flatoutfly (Jun 11, 2020)

JC Designs said:


> I would caulk as mentioned with a marine sealant. 5200, 4200, etc... thickened resin/epoxy probably won’t get a good bond because of the area being dirty and access being limited to properly prep.


Even with using caulk, it's very important to clean the area with acetone before applying. 5200 is for permeant application and 4200 is used for areas that may need removed in future. Normally 5200 for that area.


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## JC Designs (Apr 5, 2020)

Flatoutfly said:


> Even with using caulk, it's very important to clean the area with acetone before applying. 5200 is for permeant application and 4200 is used for areas that may need removed in future. Normally 5200 for that area.


Oh, thank you... I had no idea!🙏🏻


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## Smackdaddy53 (Dec 31, 2012)

JC Designs said:


> Oh, thank you... I had no idea!🙏🏻


Hahaha good thing we have people on here to keep us in line. I figured you could just run a bead of whatever caulk you had laying around over a bunch of dusty seams and it would stick good nuff!


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## DuckNut (Apr 3, 2009)

Smackdaddy53 said:


> Hahaha good thing we have people on here to keep us in line. I figured you could just run a bead of whatever caulk you had laying around over a bunch of dusty seams and it would stick good nuff!


Would be fine. The rub rail would keep it in place.


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## Dalecityusa (Sep 14, 2016)

Caulk turned our great thanks for the advice fellas!

Last thing to do is attach the original rub rail. Would I be good Using the same screw holes with a bead of 5200 ? 
Or should I fill old holes with 5200 and drill new holes ?


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## FlyBy (Jul 12, 2013)

I caulked the bottom of the rub rail.


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## Flatoutfly (Jun 11, 2020)

As some who has worked on boats for almost 40 years I would strongly suggest not using 5200 on your rub rail in case in the future someone would like to replace it. 5200 is for and if applied correctly is for permanent applications. I have removed hardware that was applied with 5200 and caused chucks of gelcoat to come off with it make a simple repair into a project. Normally you would not use either on a rub rail and normally just caulk the bottom with black 100% rubber silicon. I would just buy a little larger screws to reinstall the rub rail and do it correctly.


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## Dalecityusa (Sep 14, 2016)

Flatoutfly said:


> As some who has worked on boats for almost 40 years I would strongly suggest not using 5200 on your rub rail in case in the future someone would like to replace it. 5200 is for and if applied correctly is for permanent applications. I have removed hardware that was applied with 5200 and caused chucks of gelcoat to come off with it make a simple repair into a project. Normally you would not use either on a rub rail and normally just caulk the bottom with black 100% rubber silicon. I would just buy a little larger screws to reinstall the rub rail and do it correctly.


thanks for your insight! Gonna finish this up today using larger screws


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