An air leak could be as simple as a missing or compromised gasket between carb & manifold. Check carb for any fuel leaks; if fuel can leak out then air can leak in.
Removing the main passage plug from the carb and collecting the fuel that leaks out often helps burp the carb and get debris out.
Removing the main passage plug from the carb and collecting the fuel that leaks out often helps burp the carb and get debris out.
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