I need some serious help. I was just informed that a blister has formed under the paint on a bike I finished about 6 mos. ago. It is around the opening of the gas cap. The tank was bare metal when I got it. I followed instructions for degreasing and prepping from several board members. I used Sherman Williams Paint w/ Base Coat Stabelizer. I don't know if it is the primer or the Base Coat. Fortunately, the very detailed mural work was not affected (yet). How can I prevent it from getting worse and how do I fix the problem without having to take off the tank again.