More than likely, you simply have evaporating fuel.

As Jerry mentioned, there is a fuel filter with a check valve that prevents fuel from draining from the carburetor back to the tank on carburetors equiped with the windowed fuel valve. However, if your engine starts easily during the day after you started it in the morning, this is NOT your issue.

The well-known leaky well plug issue in the early Q-Jets (1965~1968) was corrected by Rochester in 1968. The 1968 and newer carbs do not have this issue.

Again, probably evaporation due to the modern fuel. An electric pump (at the tank) is the ONLY solution (other than remove the aircleaner and pour a couple of tablespoons of fuel down the carburetor prior to starting after the vehicle has been not started for a few days).

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
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