Whole new thread . So i was bored tonight and my shop is all clean etc. figured i would look over the recon cs 310 that followed me home for 150.... still had receipt it fired up but i could tell the carb needed adjusting... peeked at the piston before anything exhaust side clean,,,, pop off the cover the air filter is pretty dirty saw was really clean... mech shop report saw ran ruff till warmed up bad gas....i look inside air filter its dirty inside and out..... im like i better look at this side of the piston its perfect.....so i went ahead cleaned it all trimmed the limiters and will get it right tomorrow..... i am by no means a small engine mechanic i wrenched my own stuff for about 25 years and have learned alot from all the forums and trial and error....But wow these guys doing the checking on saws for resale at depot bro if you dont catch a dirty air filter but wipe the saw clean your a POS. in my book....i also popped the carb apart and checked the screen and gaskets... since it has great compression im sure once i tune and mod it it will be trouble free for years....so in the future i will be more careful about checking the recons over....now my cs 490 i dont think it ever saw any wood... "EVER" clean like i bought it new... it said new sticker on the tag....Im just shocked these guys do it for a living....Guess i am old school....Ya all have a good night....