I would appreciate recommendations and common approach to aluminum boat repair from you pros.
My friend has an aluminum boat that is taking water between the bottom of the boat and the keel, so evidently there is a split somewhere under the keel. The keel is about 100 gage or so and I believe the bottom is about .080. The keel is stitch welded about 2" on 12" or 18".

He has tried some liquid sealer on the bottom and it stopped for awhile, but is now leaking again. He told me the fit on the bottom is not that tight between the keel and the floor and that is where he applied the sealer.

My going in position is to take the motor and accessories off and turn it upside down and either TIG or MIG. Or, is it an acceptable approach to pull the lilvewells/floor and tackle it from the top? Or both?

I heard of some type of liquid sealer called GulVit (spelling ?). Not sure that is the way to go.

Reccomendations please and thanks