So, it started knocking when it didn't knock before. If the counterweight has become sloppy enough to start knocking, isn't it likely to come apart and destroy itself and/or the case? Is it possible to change the counterweight?
My brother tasked me with fixing his Husqvarna. It knocks crazy loud when running. Not much on YouTube other than checking and tightening the bolts to the frame. It's tight to the frame. The block is not cracked so I'm hoping to get it quiet and back to him. Any suggestions other than a teardown...