Transom pitting on Lowe deep v

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Pikemaster25

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Pulled my 2000 14ft Lowe Sea nymph deep v out of the garage to get ready for the spring and noticed what looks like some pitting on the transom. It was only on one side and have no pitting anywhere else on the boat. Any thoughts on what might be cause it and a quick fix to stop it ? I've attached some pictures
 

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Is there wood behind those pits?
J_boat_1.jpg
J_boat_6.jpg

Wood in transom caused this on mine.
 
Yes, there is wood behind it. Did you end up having to replace the transom or just seal up the pits ?
 
Here’s what I did.

https://www.tinboats.net/forum/viewtopic.php?f=3&t=23064&hilit=Jon+boat+rebuild+rebuild

Part 2.
https://www.tinboats.net/forum/viewtopic.php?f=3&t=29983&hilit=Jon+boat+rebuild+rebuild

Hope that helps. I went a little too heavy on the sand though, and vinyl works great too instead. :)
 
Get the wood OUT NOW and maybe you can salvage the tin! See my posts ... for the 16’ Starcraft of similar vintage, as I had to replace the ENTIRE transom skins inside & out and I surely don’t want to do that again.

Do NOT delay, the corrosion built up is a chloride crevice corrosion that feeds on itself INSIDE the tin as long as there is wood in contact there that has already been compromised. That corrosion can travel through the tin layer itself. You must remove the wood - now - don’t put it off or you risk losing the entire transom!

Open up holes until you don’t see any layer or sign of white corrosion. Clean the heck out of it with vinegar & copper pads, and rinse well. Clean again. Then I’d cover the tin inside with epoxy. For that build I’d also coat the replacement wood with epoxy, buy the 1/2-gallon kit from https://www.raka.com, call and ask for Larry or Mike. Download their free epoxy manual too.
 
Thanks for the response ! That's what I was afraid of ! When I put the boat away for the winter in December it wasn't there and I just pulled it out the other day and it was, so hopefully it's not too far gone and I can salvage the transom !! It's a 2000 14 ft Lowe Sea nymph rivited boat. Any idea how difficult this project will be ?
 
Pikemaster25 said:
Any idea how difficult this project will be ?
Do it NOW and it should be fairly straight forward ...

Posting pictures of the transom will help us let you know how difficult it might be to remove the transom cap. If that old piece is not salvagable, I have a length of heavy-duty aluminum ‘U’ channel that will allow an 1-1/2” thick transom to fit in between.

Check my signature, as I show pictures of a transom ‘redo’ using epoxy-coated wood on the 16’ Sea nymph. Plus I also did one in a 12’ Starcraft tin recently, w/ my then 12-yr old daughter, where she did all the work!

-Remove motor
-Strip transom
-Where the knee attaches is crucial - again, pictures will help immensely!
-Remove wood
-Clean rear transom skin w/ white vinegar & copper pads, then rinse
-Drill out corroded holes until clean
-REclean again ...
-Prime tin inside w/epoxy-based zinc chromate primer (a must!)
-Paint tin inside w/ any color Rust-Oleum or similar for extra coating
-Fit wood, laminate together (see posts referred to) & wet out w/ epoxy, especially the edge grain
-Install and bolt together - rivets or of SS bolts, insulate from the tin (nylon washers under bolt heads and under SS washer the Nylok nut bears against.
-Also add 1/4” section adhesive-lined heatshrink or duct tape where bolt body passes through any tin ... overkill yes ... but you already had a problem and don’t want another ...
-Paint transom inside as ANY epoxy product must be painted to prevent UV degredation
-Add old/new trim cap and any other rivet needed
-Go fishing ...
 
Awesome. I've got some time and nice weather on Wednesday to dig into it. I'll take some more pictures of the transom and what everything looks like
 
Basically, that is exactly what I did, I removed the wood and then cleaned and sealed it up with epoxy, then I cleaned the aluminum and epoxied the wood into place so that there is no way for any water or wood to come in contact with the aluminum. Plus it is a lot more solid, and I mean solid. The added benefit is that the epoxy also sealed up all the holes so I didn't have to replace the aluminum but, the corrosion was only through in spots and there weren't any gaping holes. I was going to replace the wood but ended up reusing it since there was nothing wrong with it. Once sealed with epoxy it won't effect the aluminum anymore from copper leaching from the PT. I used SS wire wheels and phosphoric acid which you can get at the hardware store to clean and etch the aluminum.

In older pressure treatment there is less copper than there is now and they used arsenic as a bug deterrent, since that was banned they just upped the copper content by a huge amount to get the same results but, really it isn't as good and is way more corrosive to the aluminum. The new PT will get those results in about 6 months.
 
There are also rivits on the transom of this boat. Do they typically have to come out to remove the wood ? If so, do I have to replace them with rivits again ...
 
Mine had rivets, bolts and some welding that all had to be undone. If you look at my pictures where I cut the weld I just riveted that back together but I also epoxied it too. It ain't coming apart without some effort.
 
Okay, so this is what I'm looking at for my transom ...
 

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First - Just to be clear ... I do not believe that the damage was caused by PT treated wood, but rather from UNprotected or coated wood that was allowed to get wet, especially if exposed to saltwater. Hulls of that vintage typically used non-treated or coated woods.

That looks to be largely a bolt-together transom, making it easy. I’d still follow what I advised, plus referring to that Sea Nymph transom re-do where I used a few of the existing transom hole locations w/ ‘greased’ SS bolts to hold it all together as it cured.

With so many bolts, buy your SS hardware in bulk and bed/seal well with BoatLife Life Caulk (my preferred choice) or 3M 5200. Don’t OVER-tighten them else you squeeze out all the goop making the seal ...
 
Gotcha. Yea the wood on the inside seems to be in good shape, but there were too holes from an old outboard that were never sealed up properly where moisture could have gotten in. And I ran it almost exclusively in saltwater last year. Would I be able to reuse the existing bolts and just put new nylock nuts on the back of them ?
 
Also, if the wood is still in good shape and I can get it out in one piece, could I just epoxy it up and reuse the same piece of wood since it's not pressure treated ?
 
Pikemaster25 said:
Would I be able to reuse the existing bolts and just put new nylock nuts on the back of them?
Sure, if in good shape, hardware can be expen$ive. Wire brush well and clean with vinegar.

Pikemaster25 said:
Also, if the wood is still in good shape and I can get it out in one piece, could I just epoxy it up and reuse the same piece of wood since it's not pressure treated ?
ONLY if truly dry ... make a tent with anything that would cover it and use a hair dryer or heat gun to flow warm air around it ... and protect from rain.

FWIW I see the same damage on 90s to early 2000s boats used in the salt, where the Mfg'rs started using untreated or uncoated ply, to get away from the PT-treated wood issues. 'Salt' has its own issues. And as I said, that corrosion is a 'chloride' precipitate corrosion so you MUST remove all traces of any 'white' residue or corrosion.

Sit back, think it through and you'll be OK ... and we're here to walk you through any obstacles!
 
Got the cap off. Things look good so far. I imagine there is moisture somewhere in the wood, but it looks bone dry on the top
 

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That looks almost exactly like the lumber used on my boat, it is a CCA type treated plywood and is used in marine construction, used to be common, lots of pontoon boats use it for their decking but, usually, if they are a decent builder will put down and insulating tape to prevent the wood from actually coming into contact with the aluminum. The CCA treatment has copper but, no where near what they use today at the lumber yard. The CCA has arsenic in it and its use has been severely restricted. I think it is still available though, not sure. Unfortunately it will eventually cause corrosion if it gets wet and even though mounted in a transom like that is is pretty much shielded form the weather it still gets wet.

I was going to replace my wood but It was in fine condition after over 15 years. I couldn't see just tossing it out. That is why I just sealed mine up with epoxy and then when I reinstalled it into the boat I went ahead and just glued it in, again with the g-flex thickened epoxy, that helped seal up the holes from the corrosion. You need to be sure to thoroughly clean the aluminum before doing this, or else it will just corrode again.

If it is reusable, I would reuse it, you can't beat it, it will last forever. If it is wet then let it dry for a month before sealing it. You won't know until you remove it completely. Good Luck.
 
I've got the same problem. Do you use brazing rods to fill in the holes once cleaned out? That's want I was planning to do.
 
You can certainly do that, mine got filled in when I epoxied the wood in.
 

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