Several years ago I hit hard on the oilpan in my '68 Corvette when going over a speed bump coming out of a casino in Reno, NV. It was late afternoon on a Sunday and the closest garage that was open used J-B weld to plug the hole (about the size of my little finger). I drove the car 200 miles to home and it never leaked another drop. Of course I had a new pan put on the next day but it proved to me the value of J-B weld. It sure should seal a gas tank leak.
