1929 Indian 101 Scout Gas Tank fix

The gas tank had a slight drip so I tore into 4 layers of fixes to find out why. There was some tar, blue stuff, tan stuff and solder but you can see the petcock is completely loose. Maybe if I tar it all the way to the carb it will seal effectively? If anyone can point me to some videos to fix this that would be outstanding. I have 3 weeks to get this bike ready for the cannonball.
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[@steverix4903]

Just an observation here, mr greasyside, but could part of the prob be the size of the petcock? with the rocking couple vibration common to v twins, something that weighty coupled only to thin sheet steel is a disaster waiting to happen...you've cleaned it nicely now....take it to a plumbers merchant and ask if they have a brass tank fitting...these are like a flanged head fitting you cd drop into hole from the inside, then tighten the brass nut,,then fit a (smaller) petcock into the thread.try!