As a general rule, the reasons a generator will stall when the choke is turned off are due to stale fuel, a clogged or restricted main jet, a clogged or restricted pilot jet, a loose fitting carburetor, or damaged carburetor gaskets. When the choke is turned off, the carburetor allows more airflow into the combustion chamber. If the air-to-fuel ratio is not correct when this takes place, then stalling will occur. This can be a fuel problem or an airflow problem.
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