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For vapor lock nonbelievers

That would be me.

The catch-all leg is simply a typical gas train set-up for any industrial gas fired burner.

Ethanol evaporation is closer to water then to gasoline, so I'm thinking that this makes no difference in terms of vapor lock.

Fuel has to flow through the tank, settling bowel [with a clean screen] and down the pipe to the carb where if in proper trim the float valve will stop/start the flow of fuel if the carb is open to the free flow of atmospheric pressure.

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