It could also be the jet wells, where those jets screw in, if you take the carb apart and flip the bowl so you can see the underside you will see two little round bumps, they are bowls that are epoxied to the main body, the epoxy gets old and breaks down, clean off the loose epoxy and smear a layer of JB weld or seal all around it let it dry completely. you can test the jet wels by simply puting gas,water, exc.. in it and watching for drips.
