Wayne, it's likely the paint on your Toyota was not completely cured yet. I know it was dry to the touch, but many air or moisture cured paints (such as Rustoleum and Brightside) will take 3 to 6 months (or more) to completely cure. The time required is determined by many factors such as temperature, humidity, etc.

One illustration to help you understand this: If you painted the car and then parked it in the garage over night several days later, it's likely that the next morning you could smell fresh paint upon walking into the garage. This smell is gasses being released from the paint into the air in the garage. This process continues for months after the paint it applied. It gradually slows and within a week or so the paint no longer gives off any noticable smell, but it is still releasing solvents at a slower rate.

Some chemicals in regular automotive paint are quite strong. In fact, there are times when one brand of automotive paint will lift another brand of automotive paint. That's why it's best to do a test panel first to verify compatability when changing brands of paint.

There are several ways to reduce the chance of this problem. The first is to use hardner in the enamel paint. I have no idea if it's even available for the brightside paint. Of course when using hardener, one MUST take all the safety precautions necessary for isocyanates. (proper respirator, paint suit, proper gloves, etc.) The painting can't be done in your home garage! This obviously removes this option from consideration for most of the folks on this board.

The second option is to use a sealer between the brightside and the traditional automotive paint. Talk to your automotive paint store about this option. The store fellows will probably have no idea what will work with a marine paint. So you may need to ask them how to paint over some synthetic enamel which was applied without any hardner.

The third option is to wait a longer period of time before applying the automotive paint.

A forth option is to find a brand of automotive paint which has chemicals which are not as strong.