i lost track but it has about 40 days falling on it at about 7 tanks a day. tanks last under 40 minutes with this saw. then i used it for about a week building heli pads. not sure how many tanks burned doing that. it has since been pulled apart, inspected thoroughly, cleaned of all carbon, and ported. bottom end is nice and tight and the top end still has all machine marks on the piston. the engine i would say isn't far off new when looking at the parts. in the pics the exhaust port looks wet. amazes me as it's an AT saw. that's running lucas semi syn 40:1. if i don't get $600 for it i will keep it. this saw would last a firewood guy a lifetime unless of course he was cutting firewood to sell then maybe he might stand a chance at killing it before his time is up lol sure doesn't look like it has that much time on it but that is 100% honest.