Pressurizing the interior to find leaks

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Matt19020
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Pressurizing the interior to find leaks

Post by Matt19020 »

Well I was baffled on how I was getting water in from rain but after using a hose for about 5 hours I was unable to find any substantial leaks. I remember a technique from a magazine I read years ago about pressurizing the interior of the boat and using a soapy solution to identify the leaking area. I believed this worked! I was able to identify 4 areas that water could be coming in, and 2 of those areas appear directly where my leaks were found on the interior. Here was my technique and hints to make it go smoothly.
Most of you will not have the port I have (it was used to exhaust an air conditioner) where I was able to connect the air source so you will need to make up some type of hatch adapter.
Material:
3” scotch Blue tape (use this brand the knockoffs just are a pain in the A$$)
Pressurized Garden sprayer (you will go through a lot of liquid fast normal spray bottle just didn’t cut it)
Dish soap
Air source…I used a leaf blower because it was handy but the article I read used a carpet drying fan (I think you can rent them for about $25 at Home Depot)
Weight or second person to put or stand on topside sliding hatch
Crayon pencil or camera (To identify exactly where leak is)

Attach your air source . Tape up the hatches to the best of your ability…don’t go crazy you don’t want to blow the windows out! Just get the obvious seams. Place weight or second person on top hatch forward 1/3 area. When you turn air on the hatch wants to lift up to let air out and this will foul your taping job….once this is all wet you will not be able to retape until the entire area dries again. Mix up dish soap and water into garden sprayer (I was pretty generous with the soap). Turn the air on and get spraying. Look for bubbling bubbles… I like the camera because you can identify exactly where leak is. The whole process took less then 45 minutes. I hope this helps anyone. I will post in Mod section for easy reference.
On a side note anyone know how to reseal the rub rail? I was just going to see if I can get some clear marine silicone in there.

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http://i151.photobucket.com/albums/s152 ... 04a969.mp4

http://i151.photobucket.com/albums/s152 ... 8c4468.mp4

http://i151.photobucket.com/albums/s152 ... a404ce.mp4
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Ixneigh
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Re: Pressurizing the interior to find leaks

Post by Ixneigh »

I can't wait to fiberglass over my hull to deck joint. Also going to add a sheer strake for strength.
Ix
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133bhp
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Re: Pressurizing the interior to find leaks

Post by 133bhp »

I cant make out where the leak is on the vids, top or underside? I've rain water coming in from the front v beath drain holes, possibly salt water too in waves, but sealed all the fittings/top rubrail back to the mid section, wondering if running under rubrail and in?
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opie
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Re: Pressurizing the interior to find leaks

Post by opie »

bartmac
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Re: Pressurizing the interior to find leaks

Post by bartmac »

Hat off to a brilliant idea :D :D :D

My rub strip was damaged so removed it and cleaned all goop and regooped....not because of a leak but found the general state of the join to be wanting...fitted a new rub strip....looks good and don't think water is getting in there!!
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Matt19020
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Re: Pressurizing the interior to find leaks

Post by Matt19020 »

133bhp, The bubble seem to be coming out of the underside of rub rail. In my opinion I can not see how the water is coming around the rub rail and flowing inside....however the evidence shows that the bubbles are exactly where the water is coming in. Today I siliconed the entire underside of the rub rail. It is supposed to rain Tuesday so I will check then. I hope I do not have to do what Opie did that looks like a lot of work. Since I am the original owner I know there was no hard dockings, however I am wondering if this terrible winter formed some ice in there and some sort of separation occurred...will keep you posted...
bartmac
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Re: Pressurizing the interior to find leaks

Post by bartmac »

Finding water entering either a boat or a camper is a pain.....just found a wet area in our camper and believe it or not but found water travelling thru the outside insulation of electrical wiring ie twin flex with a black outer from our solar panels was acting like pipe :D :D
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Dimitri-2000X-Tampa
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Re: Pressurizing the interior to find leaks

Post by Dimitri-2000X-Tampa »

Do leaks on the bottom of the rub rail really matter as far as letting rain water in? I wouldn't think so. I've been going around most of my deck fittings lately and resealing them which has eliminated most of my leaks. When I was down in the Keys last December, we had a couple brief rainstorms that seemed to let gallons in...but now that I have redone the fittings that I know were leaking, I think I'm only getting a cup or two in..and I still do need to do the port side baby stay straps. I have found that mostly what the factory has sealed (ie. stanchions and that sort of thing) are holding up pretty well. But what the dealer did (ie. clutches and pulleys and things like that to lead the lines aft) is leaking badly after 13 years. I also did re-silicone all 3 of the chainplates so that may have helped some too since all sailboats tend to leak there after a while.
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Matt19020
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Re: Pressurizing the interior to find leaks

Post by Matt19020 »

Dimitri, I am with you, I would not think the leak under the rub rail would matter but that is where the major "bubbleing" occurred and it also is in the same location as the leak inside. I did see some bubbles around the daggerboard pulley bolts and 2 wire through holes I gooped all three...I did what I could...with that and some luck maybe it will work.
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133bhp
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Re: Pressurizing the interior to find leaks

Post by 133bhp »

I think it must "wick" under and through the deck join. no sign of running down from the fittings, so must be a area behind the inner skin/rubrail not visible. I'll try sealing the underside. Thanks all.
jbgibbs99
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Re: Pressurizing the interior to find leaks

Post by jbgibbs99 »

After getting some small but anoying leaks I decided to re-seal the deck joint on my X - took just over a day but worth it - no more leaks (I think). So far a few heavy rain days and completely dry.

I did the following:-
Pulled the rubrail off one side at a time and left it on the bow so I wouldn't have too much trouble re-fitting it. It's akward taking the white caps of the end - lots of gloop in there - but underneath the caps are a couple of screws fixing the rubrail.
Took out all the bolts and scraped off the gloop - then working a foot or two at a time prised the two halfs open with a screwdriver just enough to scrape out the gloop and clean out the joint.
Then scraped all the gloop from the inside of the rubrail.
Then working a foot or two at a time used the screwdrivers to hold the join open and put a bead of 4200 on.
The put a blob of 4200 in each hole and put the bolts back.
Then ran a bead of 4200 along the top lip and over each bolt.
Then put the rubrail back - it pushes over the top of the bolts and clips over the bottom of the bolts. This took a bit of effort as it's cold here at the rubber was a bit stiff.
I didn't seal the gap at the edge of the rubrail - or the bottom of it - as I wanted the water to be able to run out.

I also dicovered that one of my anoying leaks at the stern was a hole where the deck joints end underneath the white rub-rail caps.
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Matt19020
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Re: Pressurizing the interior to find leaks

Post by Matt19020 »

Well I am a little disappointed....after the first rainfall since testing I was only able to cut the interior leak down by 1/2.... back to the drawing board........
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Dimitri-2000X-Tampa
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Re: Pressurizing the interior to find leaks

Post by Dimitri-2000X-Tampa »

I still think most water comes in via the deck fittings...or also stuff like the hatch bolts, companion way track, etc. Then the water wicks its way down into the bilges. And I presume you have all 3 of your chainplates sealed too?
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seahouse
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Re: Pressurizing the interior to find leaks

Post by seahouse »

Hey Matt - you got some of them anyway!

Didn't Highlander have a leak at the area where the main hatch slides at one time? It wore through the gelcoat, I believe. If yours leaks there, and someone were standing on the hatch as you said, you might not have detected it during the leak test?

:?: :?: :wink: -B.
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Matt19020
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Re: Pressurizing the interior to find leaks

Post by Matt19020 »

Seahorse,
It is possible that it could be around the hatch because when I pressurized the cabin my tape came loose around the hatch and could not retape since it was wet ....I tried my best to see but that area was unclear....I am gonna have to deal with it for right now. I am gonna use a 110V fan on a timer to kick on every 12 hours for 12 hours while the boat is slipped to dry any water that accumulates when I am not there....bottom line, It Sucks!!
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