MOst auto parts store will carry a putty that you can use to repair small holes in your gas tank. It is a putty that you mix together like those steel sticks, a two part with one on the outside and ond one in the middle. All you do is knead it well and put it over the leak. Works real well, even on wet metal. I usually keep a stick around because you never know. I've even seen it work on small seperations in the seams of a tank. Used it on a motorcycle tank once, years ago. Still holds today.