These engines are not always assembled correctly. You might have gotten a bad batch, so try another store. The one I am running right now had a carburetor develop what appears to be a somewhat rare leaky fuel bowl float valve. I just called HF and since the carb is an EPA warranted item and I told them the carb was bad, they sent me another one for free. This same engine had been assembled with the intake gasket reversed, making its air intake restricted. Probably related. But the new carb worked great out of the box and even better with the enlarged jet than when I bought the engine.