Hi sometimes these saws can boil the petrol in the tank on real hot days. Some folk are careless when filling the gas tank and let petrol mix spill onto the cyl. This oily residue can cause fine sawdust to collect on the fins on the cylinder and each time the process is repeated the problem gets worse intil the fins are clogged . Remedy is to dismantle far enough to be able to clean the fins and be more carefull when filling with Gas .Mix or Juice etc Joe
