280z fuel tank repair Question

[Graphitez]

Hello, A few weeks ago i removed my gas tank from my 76 280, my plans were to do a full tank restoration. I took a look down the filler neck and to my surprise there was basically no rust inside what so ever. The tank on the outside had a bunch of surface rust, so i sent it out to be sand blasted. When i got the tank back it looked great, no visable holes or anything. So just to be on the safe side i capped of all the fittings,and i made a filler neck cap with a valve stem. I filled the tank with 10PSI and then began to do a soapy water test. I spent about a 1/2hr doing this and found nothing. I then prepped the tank to apply POR15(semi gloss black)to the outside. I applied 1 full coat to the whole tank,a few days later i went to put a 2nd coat and found a leak right near the fuel feed nipple(little bit of gas left in the tank),it had eaten the POR15 completely around the fitting. There was a hairline crack in the Braze(weld)that mates the nipple to the tank, So that brings me to my question, What is the best way to fix this? I am pretty sure they brazed fittings on back then,It looks like solder not a mig/tig weld. I was thinking taking a torch to it to blend(re-braze)in the crack,Or would a little bit of JB weld do the trick?

Edited December 29, 2010 by Graphitez

[Snailed]

It's best to strip the area and bring it a shop that can braze it and leak test their work for you. I would try a radiator shop first. Leave a hose running in it for a while to flush out any left over fuel, then run air into it for a few hours to dry it all up before you bring it.

[Graphitez]

It's best to strip the area and bring it a shop that can braze it and leak test their work for you. I would try a radiator shop first. Leave a hose running in it for a while to flush out any left over fuel, then run air into it for a few hours to dry it all up before you bring it.

Thanks for the info,now the hard part is finding a radiator shop in my area.