Resurrecting this thread.
Replaced the carb. Symptom was fuel all over the lower cowl, apparently coming through the venturi. No
idea what was wrong. Sent it in as a core and included a SASE with a request to let me know, but never heard back.
15 hours on the replacement overhauled carb (this time from Marvel-Schebler, and it's doing the same thing!! Slightly different symptoms though:
I just got home after being away for two weeks to find more fuel dribbled on the lower cowl, but it doesn't appear to be coming from around the carb drain plug like I thought. There's a very small and mostly evaporated puddle on the top of the air box underneath the carb, --forward--of where that drain plug sits. I loosened the air box and the screws are wet, as is the gasket between the air box and the carb. It's wettest at the rear two attachment bolts. I have to wonder if the fuel level is simply too high in the bowl? Or, if fuel is somehow seeping out at the drain plug and getting splashed all over the place? The engine hasn't been run since I left. But it's weird that the fuel puddle is __forward__of that drain plug, as the plane sits nose high. That makes me think it's seeping out of the carb bowl someplace.
And yet, it's totally clean where the bowl attaches. Could it seep into the venturi then drip down somehow onto the airbox and then out? And could the wet air box attachment bolts be from fuel being spread around by the running engine?
The engine runs absolutely fine. These symptoms are nearly identical to the previous carb, except that this one only has 15 hours on it since overhaul. I wonder if they adjusted the float level for the carb sitting level, and not in a nose-high position as for my PA-12? I wonder how bad is it to have the float level be too high, if that's the issue? The engine is not flooding or giving any symptoms other than these fuel stains. Some of the time it's worse than other times. Just weird. I kind of need to at least come up with a theory.
Thanks for your thoughts. I will NOT be replacing this carb. If it's going anywhere it'll be down to that carb shop in TX that Steve mentioned.