I was getting black smoke out of my Briggs and Stratton Craftsman 675 mower, so I removed what I thought was the muffler. There is an arm that pivots around 20 degrees and goes upward into the mower, and now I cannot determine how to reconnect it to whatever it is supposed to reconnect to. Does this make sense to anyone and can anyone help me figure out what it is supposed to hook on to? Without it connected, the mower still starts, but it stays at an unsustainable low RPM and then almost dies on me. Thanks!