Well, It either bugs you enough to fix it, or it doesn't. I think it does bother you a bit, or you would not have started this thread. Here is my thought. I am totally anal with paint runs. I would fix that run. Even if nobody would ever see it, I would know it was there. It will take very little time to sand the run, scuff the entire pan, and respray it. I do a LOT of painting, so here are a few questions for you. The pan looked pretty rough. How did you prep it. If all you did was sand it a bit and spray paint on it, the chances of a good, long lasting result is pretty low. The rust needs to be treated with something. There are lots of treatments that will kill rust and/or convert it into a hard, black substance. Next question is what kind of paint did you use? Some are better than others. Rattle can or spray gun? Properly applied, Dupli Color engine paint works very well. Did you use any primer? As rough as that oil pan looked, you should have. Unless the paint can says that DTM (direct to metal) application is OK, I would use primer. Actually, I would use primer anyway, but if you don't want to use primer and are VERY careful and make your first few coats light and observe an appropriate flash time, those first few coats can serve as a primer. How heavy were the coats. Remember that the first coat is ALWAYS a light coat called a tack coat. never go for coverage with the first coat. One very light coat, followed by a medium coat, followed by a medium wet coat, followed by a wet coat is the way to go. Observe manufacturers suggested flash times; giving a bit more flash time before the final wet coat. go for about 50% overlap and move fast enough to help avoid the runs. After a few passes, you will find a speed that will work.
