Re: Carpet glue and corrosion.
What type and year of boat? Have you tried removing the carpet yet and seen the type of glue was used?
I removed all the carpet from my 01 Crestliner and it was an ordeal. The glue they used was a hot-melt type glue (clear in color) that couldn't be scraped or sanded, it had to be chemically removed. I was doing this in August which helped as the hot-melt glue would bake in the sun and I could pull the carpet off the partially softened glue. If the hull was stone cold I wouldn't have been able to get it off easily. I tried one night and gave up, the stuff was stuck and not letting go, chunks of backing coming up and the fibers still stuck down. If I was doing this in cold weather, I would have put a space heater up against the carpet I was trying to remove, to let it heat-soak for a while, maybe the outside of the hull would work better?
Once I got the bulk of the carpet off the aluminum I soaked paper towels in lacquer thinner, slapped them on the glue to soften it, let it sit for 10 minutes applying more LQ thinner where needed, then came back and wiped up the gooey mess. I learned to let the thinner work it's magic and not to try and scrub the glue off. I worked a 1' section up the hull and it probably took 6-8 hours to remove the carpet and glue residue from the 18' hull, just the hull, not any of the decking or interior panels.
I have to say, this was the worst thing I had to do on my rebuild, stinky, nasty work. Oh yeah, wear a respirator and skin protection. I ate through a set of heavy dipped chemical gloved in 2 hours, then started using 2 nitrile gloves on each hand, doubled up gloves. When the top glove ripped, I'd put on another. Using all that thinner (5 gallons I think) I wanted to limit my exposure as much as possible.
I wouldn't use JB weld on the transom skin, metal flexes too much and JB weld is too brittle/hard. I've never used Gluvit, but I think that would be a better option as you want an epoxy that stays a bit soft and flexible.
Thanks-Alan