Weeping transducer through hole.....

kloudie1 · Apr 22, 2013

From the looks of the wood, I'd say that the wood has rotted from under the securing ring.. One thing you might try would be to hold the transducer so it can't turn .. Back off the ring until you have about a half inch or more clearance between ring and wood. Plumbers putty or butyl .. roll into a string about 4-5 inches long and 1/4" diameter, wrap it around the transducer body under the securing ring.. Hold the transducer again so it doesn't turn and tighten the ring down to squish the butyl or thick putty down into the gap between the body and the wood.. This may get ya thru the season.. keep an eye on it.

Edit: Don't push on the body when the ring is loose.. The water pressure should hold it into place, but it wouldn't take much of a push to get the water flowing pretty good.. have a plan B in mind.. plug or a quick pull out of the water .. The seal on the outer part of the thru hull is broken and letting water under it and out the hole where the body comes through the wood .. so the outer part is not stuck all that well to the hull.. Try to look carefully at the body to make sure it is not cracked under the ring ..

Jackdaw · Apr 22, 2013

magic goo?

I'm thinking this is not the type of problem where you want to take the cheepo way out. That thing is keeping your whole boat afloat. You too when you're on board.

onecoolair · Apr 22, 2013

This is the worry of every boat owner

This is the worry of every boat owner...If this was me...To try and save money for the long run. I would consider is there anything else I have been needing to do ? If not then its a quick haul.
But that's if it was me....
Okay....
If it was just always damp looking and not leaking. I would just keep and eye on it till next haul in a few months. I have a thru-hull that looks like yours. Plywood used for backing.:naughty: But is not leaking. I am very careful to not mess with it and keep a close eye on it. But in your case its currently leaking. And running the bilge on a regular cycle. So you need to address it... Tightening the nut more will only crush the rotted plywood running the risk of making it leak more and thus fail....Covering it over with 5200 will just destroy the thru-hull fitting making it a mess and harder to do a proper fix later.. Get all your ducks in a row....Like New backing plate from a scape piece of fiber glass laying around would be best for backing. Tools,caulking,etc....Get everything set...Then let the yard know your problem ...Check with the yard and see if they can give you a break on an end of day quick haul. End of day would be best then boat could just sit over night in the sling. They can set it down with wood blocking under keel and quickly place a few stands but leave slings in place. This would make boat stable enough so you can get up there to do what you need to do. With all the right tools and supplies handy plus a helper it should not take more then an hour or two ... You can then fix her up and have her ready for an early morning launch....That way it would be easy for yard to just set your boat back in the water without you there. This way they can just set it aside and not hold them up for their start of work day.
Best of luck.

Benny17441 · Apr 22, 2013

These transducers are removable for cleaning or replacing. They sit on a trhu-hull sleeve and use a rubber "O" ring to seal against water entry. A dummy plug should be on hand to be put in place of the transducer while it is out. With the boat being out of the water for a long time there is the possibility that the "O" ring seal dried up and could now be allowing water through. This is just one possibility , if you are sure the water is sipping in through the wood block then it could very well be rotten and in need of replacement. Just make sure that you ascertain the source of the leak as sometimes it could be misleading.

centerline · Apr 22, 2013

its possible that the wood could swell or has swollen and caused damage to the thru-hull fitting causing it to leak. the inner rubber O-ring is probably ok, as it seals between the housing and the cartridge... but the install job is a bit on the shoddy side and is probably leaking between the hull and the housing. and I think there is another o-ring there, but if the backup support has failed, it wont hold out the water.
and if you are getting a little bit of water now, it could soon turn in to a lot more water....

tomgrigsby · Apr 24, 2013

Picture of the transducer itself is too dark to see what is happening. If it is like mine, the O ring thing noted above could easily be your problem. Is the transducer dry all the way around above the plywood?

artboas · Apr 24, 2013

Only solution

Delawaredave said:
Newbie. Boat has been out of water for few years.

Just put boat in water. Transducer through hole is weeping between plywood block and inner hull fiberglass. I tightened ring down a little - no change.

Boat in water - wood soaked. Collected about 6 oz of water after 1 hour or so - about 3/4" high in vee.

Two questions please:
1. Is it possible that plywood will swell and close the leak ? (Maybe I'm dreaming but someone told me that)

2. Is there any "magic goo" that could seal this from inside ? Would need to stick to wet wood. I don't know if 3M 5200 could do this or Marine-tex ?

Thanks !!!

Here's pic:

I had a similar problem with a cracked through hull.
You need to haul the boat. No way around it.
Remove the through hull.
You will find that water is entering the glass layer:
Let it all dry out
Clean up hole, and seal with epoxy.
Install new through hull with fresh backing plate.
Use 4200.
Don't risk trying to fix this with the boat in the water. You'll regret it.