Suzuki: intake manifold, craked, intake manifold

Question
its leaking gas how do i tell if the gasket or the manifolds craked

Answer
If it's leaking gas to the outside while the engine is running, it's probably not the intake manifold, because if it were cracked, the vacuum of the engine running would suck air(and gas) into the manifold, and the engine.  Possibly a float level issue on a carbureted engine, or a line or fitting on an injected engine.
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scotty