Trying to pin down leak source on a new to me boat

[williamtl]

Let me save you some time. Here is my three year journey. I also have a 26D.

I have ...
rebedded all stanchion bases
Rebedded bow pulpit (those bases are not the same)
All 4 standing rigging pass through sealed (drilled out rivets and replaced with screws were I couldn’t get to back. On those I put bolts. They are not load bearing.)
The pop top does not stop rain in even a light wind (I used the door gasket from a ford pickup)
The handrails on the pop top.
The screw on the goofy front hatch (I’m allowed to make fun of it, I own one too)

All this and three years and it’s finally dry.

Butyl bed it tape is your friend.

[Hoosierdoc]

Thanks. I have 50’ of 1” butyl tape ready to go. Going to try to gain access to everything Tuesday and then rebed everything I can Wednesday. Also going to reseal top of rub rail.

I learned a few lessons in boat buying this year

[Secondshift]

Originally Posted by williamtl

Let me save you some time. Here is my three year journey. I also have a 26D.

I have ...
rebedded all stanchion bases
Rebedded bow pulpit (those bases are not the same)
All 4 standing rigging pass through sealed (drilled out rivets and replaced with screws were I couldn’t get to back. On those I put bolts. They are not load bearing.)
The pop top does not stop rain in even a light wind (I used the door gasket from a ford pickup)
The handrails on the pop top.
The screw on the goofy front hatch (I’m allowed to make fun of it, I own one too)

All this and three years and it’s finally dry.

Butyl bed it tape is your friend.

Very good info and finally someone who
"Gets me" about that fwrd hatch closure.
I didn't have a spare door seal handy so I opted for foam pipe insulatipn stuck with 3m double sided foam tape. Been good for
5 yrs. Wondering how did you stick the door
seal? Would be much more resistant to damage than my foam.

Best Regards,
Ed W

[Hoosierdoc]

Well today wasn’t as productive as i’d Hoped, per usual. I did get the rub rail sealed and very happy with that. Also rebedded the chain plate covers but i’m Going to redo two of them as the one rivet is a tad loose on them.

I removed my bow light to see if it could be leaking underneath and found this

Had been mounted with sticky tape and very loose. Eventually I should have a somewhat dry boat.

[Hoosierdoc]

So, I applied 4000 UV to the top part of rubrail to reseal that. Also rebedded chainplate covers with butyl tape and covered a few random through-deck connectors and boat is dry after half an inch of rain!

[hellosailor]

doc-
You'll find plenty of older threads about finding deck leaks. Personally, I like closing up all ports and vents, then using a shopvac or leaf blower to "inflate" the boat, by putting the exhaust hose or blower through a heavy cardboard in the companionway or a port.
You then very carefully spread a bucket of soapy water on deck, working your way aft form the bow. Every leak will betray itself by blowing soap bubbles. And if you walk on that soapy deck, you're pretty much guaranteed to fall off the boat--so wash it down before walking on it.
Stuff that couldn't possibly be the problem, winds up blowing bubbles. There's no better way to find it all. You'll have your work cut out for you, but once you get everything sealed properly and can enjoy a dry boat, that's priceless.

[hlev00]

The blower technique is an interesting idea. I used to do something similar with racing dinghies where the hull is supposed to be air/water tight. I don’t think it would work on my Beneteau. Too many passages / conduits between inside and outside. I wish there weren’t. It worries me if we were to get rolled but we don’t sail in those conditions.

[sailjumanji]

We have a Seawind 1160 Lite catamaran just nearing completion at the factory in Vietnam. Two days ago, they sent me some progress pics, including this one of "leak test" underway. I think it takes two guys to hold the hose.

[hellosailor]

A Biggerteau might require two blowers but given enough masking tape or poly wrap, you can close off the holes and just one will be enough to do it. In theory you can use an industrial smoke machine, which is what car dealerships are supposed to use for tricky leaks. Let that find the big holes, then come back with the blower.

Those 4" fire hoses DO require two people, one works the hose, the second braces the first and helps wrestle the pig. I've used a smaller dockside fire hose to wash down a boat after a passage. Must say, it made the cleanup easy. "Lather, rinse, repeat." (G) Of course now that everything is infested with electronics, that's not quite the same.

The problem with leak testing with a fire hose, is that water travels. It can get in over "here" then run along a conduit or strut or simply the underside of something for six or ten or fifteen feet, and all you see is the drip at the far end. Doesn't tell you where the LEAK actually is, unless you're spraying and watching the obvious seals, i.e. hatches and portlights.

[Cadence]

I'm sure the fire hose would point out major leaks. I'm not sure about the hard to find ones that generally are just a little water getting in by no more than capillary action.

[hlev00]

We have a leak that seems to only occur when we are beating in seas that come over the bow regularly. We haven't tried a firehose but have certainly tried the lots of water at the dock and on the hard to no avail.

I have an ultrasonic sensor that has its own ultrasonic sound source. It has been helpful in some instances though still not in this one that seems to require the boat being stressed in some way, or at angles not found ashore.

[sailjumanji]

Really, water would come in via capillary, but not with a 3-4 inch stream of high pressure water?

Originally Posted by Cadence

I'm sure the fire hose would point out major leaks. I'm not sure about the hard to find ones that generally are just a little water getting in by no more than capillary action.

[Cadence]

Originally Posted by sailjumanji

Really, water would come in via capillary, but not with a 3-4 inch stream of high pressure water?

I'm not sure if that was agreement, question or disagreement? Capillary action takes a sustained exposure to water and it does not need to be much since it is slow. It's the slow leaks that are hardest to find. Deck fittings, portlights and chain plates are a few things that come to mind especially if getting in behind a finished interior surface. A wooden boat can become dry rot city. JMHO

[Secondshift]

[QUOT:Hoosierdoc;2782551]So, I applied 4000 UV to the top part of rubrail to reseal that. Also rebedded chainplate covers with butyl tape and covered a few random through-deck connectors and boat is dry after half an inch of rain![/QUOTE]

Congratulations. I like to inspect after a good heavy rain, though we've not leaked in years.(in the M26 anyway)
Unless it's through a forgotten open hatch.

Ed W