mine leaks there too, I ignore it and hope it goes away. I found a brand new rebuilt rochester in the junkyard that didn't even have a grease mark on it. I took off the 4 screws and the inside of the bowl was brand new looking. The gas inside was still good and smelled fresh. The side of the carb had a "rebuilt" sticker on it. I think the PO tried to get the truck running but gave up and junked it. Anyway's 16 dollars at pick and pull and I'm going to put it on if the leak persists on the original. If I try the filing method and it works I'll keep the other carb for a future two carb offy setup.