Pitting in Keel- fill or paint over (time sensitive question)

[AuChante]

Link fixed. Talking about under the stands and bottom of keel.

[more]

Originally Posted by AuChante

This expands a bit outside the thread topic, but I visited today and have questions. I may not be savvy with bottom paint, but I know some stuff about regular paint and I’m worried. There’s bubbles, leaking bubbles, unpainted portions (including bottom of keel sitting on blocks) and leaking rust. Thoughts?

this is problem with hull,not problem with bottom paint.

[Don C L]

Well the blisters are typical osmotic blisters with the dark acidic liquid leaking out. At the keel/hull joint I couldn't quite tell if that leaking is rust or from the osmosis. Under the pads: before they put you back in the water they will lift the boat and move the stands and then you paint those areas. Under the keel, they will lift the boat and you crawl under there and paint the bottom of the keel before it goes back in. Those blisters should have been dealt with before painting the hull, though they may have become more pronounced while out of the water. If you want to fix those, and I'd say it is a good idea, it will take more yard time, grinding out the blisters and filling and barrier coating and repainting. Since the liquid in the blister is acidic and the acid, I have heard, catalyzes the reaction, I washed them out, after they were ground out, with baking soda solution on a friend's boat as part of the prep process. I kept applying the baking soda until all the bubbling stopped. Then of course they had to be dried out. I can't say if it really helped prevent future blistering in those spots though, he hasn't pulled his boat out since then. There are threads here that discuss how to deal with osmotic blisters.

[Don C L]

BTW, they did prep and primer under the keel, right?

Also, the liquid coming down the keel that appears to be rusty, if it is rust, where is that liquid coming from? Is there water in the bilge?