It's the puppy pee gas we have now days. I run no ethanol in my 2 old cars and it's still an issue. Like S'cuder mentioned, I can shut the engine off and hear the boiling under the hood. I have a stock 2 barrel on my 318 and a AFB on my 273. They both will do it. If you let them sit over a few days the bowls will be dry. I really need to install a electric charge pump to prime them. The fellas that have done that say they work well.
