Mine is at high limit on crank eccentrics... i didnt find ANY wear on rod or journal... interesting, i may put it back together and run it. i ran this mower at high throttle for 3 mowings ( about an acre each time) never skipped a beat, ..just that annoying low speed knock.when i saw the counterweight assembly, i wondered if that was the knocking, maybe its characteristic of these engines?my block did not seem to be worn excessively, i never found discard specs on that