A lot of these tanks have the same problem due to poor quality control by the manufacturers. Here's what I did to fix mine and it has been leak free for three years. First I removed the tank and drained the gas. Then I let it air dry with the cap off overnight. Third, I put water in the tank and sloshed it around and drained it to make sure there were no residual gas fumes left. Next I cleaned the area where the studs come out of the tank with a Dremel tool and wire wheel. Finally, I used a small propane tank (mapgas will work too) and general purpose rosin core solder on each of the studs. Solder the tank upside down so you don't get solder too far down the threads. The two rear studs on my tank were not soldered at all. After the tank cooled I dried the rest of the water with a hair dryer, filled the tank halfway with gasoline and let it sit for a couple of hours. When there was no sign of leaks I reinstalled it and have been using it ever since. These tanks are very thin metal, if you try to weld it you will likely burn holes in it. Finally, follow everyone else's advice and don't over tighten the nuts. Good luck.