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Aluminum gas tank repair and question

I’ll start with the question. The US Panteras were retro fitted here with a wrap of fiberglass, supposedly for safety reasons. Something I read made me think that the European cars with aluminum tanks were never wrapped. Anyone know if this is true? I removed all of it when I started looking for the leak. It is only one layer thick (0.03”) and rips very easily. It seems impossible for me to believe this would have any benefit in a crash severe enough to rupture the tank. So I’m considering not recoating it and just painting it, probably silver. Any thoughts are welcome.

Now the story and repair. Zonkey's aluminum gas tank started to leek a few months ago which came as a big surprise as it was clean with no sign of corrosion 14 years ago when I did the restoration. The car has been apart for the last 5 years as a result of a rear ending. I'm now starting the re-assembly and repairing the tank is the first thing on my list.

So last week I pulled the tank and looked inside. Everything was very clean except for a few patches of some very strange stuff in spots on the bottom of the tank. It was somewhat granular, sort of like clumps of very large salt crystals stuck together. It crumbled easily with a little finger pressure. I didn't think much of it at the time as I was pretty sure the leak was somewhere other than the bottom as it had stopped leaking with 3 gallons or so left in the tank. Under each clump was a discolored spot which turned out to be corrosion. I have an in tank electric fuel pump to feed 4.6L Cobra Mod Motor and the pre-filter sock on the inlet was gone. I suspect the the material from that was somehow transformed into the strange clumps which trapped water causing the corrosion.

Anyway, I decided to repair the leak with the POR-15 tank sealer:
http://www.por15.com/POR-15-Fu...ank-Sealer_p_64.html
It is a three step process, cleaning with their strong cleaner, acid etching with “metal ready” and then sloshing the tank with their sealer. When I started the process I thought I had one very small pinhole. The cleaning step revealed two more smaller pinholes. However the etching brought out a total of 7 pinholes. All had grown larger, and all of them were in a corroded spot. I’m confident that the POR-15 will be more than sufficient to permanently seal the tank although I may add a couple layers of fiberglass on the bottom to strengthen it and prevent possible corrosion from the outside.

Here's a picture of the bottom of the tank. The fuel pump slides down the post that sticks up.

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