74 Pontiac Grandville

[Electronic M]

Nice ride. All my cars end up with dry carbs if they sit more than 2 days. I heard an automotive YouTuber I trust explain that since they switched to ethanol as an octane booster they no longer add anti-evaporation additives to gasoline (nearly all cars are sealed fuel injection systems that don't need it) so modern gas will evaporate out of the carb vents in a couple of days.
I've also heard one of the original uses of Marvel Mystery Oil back in the 20s before anti-evaporation additives were in gas was to add it to your tank to act as an anti-evaporation additive... Haven't gotten around to trying it for that yet. Might help in my 47 Oldsmobile that usually needs a ton of cranking to fill the carb enough to run it it's sat over 2 days...If it doesn't I've got an electric pump I might plumb in and wire a prime button for. Everything but the Burban is off driving insurance and on the cheaper storage insurance for the winter now.