Obee Kaybee I just pulled the side cover off and took my shoes off and walk around in the crank case. I do find play on the piston it feels like a side to side play also up and down. I tried the same moves on my extra engines and had the same play. That is till I took the piston out and the up and down play didn't seam as bad as it looked together. I also used the screw from the old motor that sports a lower profile than the blot holding my rod on. Does not seem to help or hurt the vibration much. On the piston is there one or two rings on it?