I sprung a leak!

I have a mid 90's 12' aluminum Gregor boat I recently bought used. I noticed that where the transom meets the floor there is a lot of what appears to be silicone sealant. Anyway this is where the leak started. I have removed the silicone and underneath that is a rock hard white substance that is difficult to remove. I have removed some of it and noticed I can see a sliver of daylight through the seam where it was leaking.

My question. I have a can of Gluvit coming. Had good luck with it in the past. After getting it cleaned up and wire brushed I was going to tip the boat up and pour it into the seam about an inch thick. Do you think that will work or do I need to find someone to weld a bead across the seam? Thanks so much.

Gluvit would work, but G-Flex 650 is better as it is a flexible epoxy. Either would need to be painted over to protect it from UV, or at least that which doesn't weep into the seam.

Thanks so much Dale. I went with Gluvit as I already had it on order. The boat is all prepped and just waiting for warmer weather this weekend.

As long as your getting all of the old crap out see about getting it welded.

Too late!! It's full of Gluvit and dry as a bone. I seriously thought about getting it welded at first but the shops are booked for months. Nobody wants to work anymore.