They are right about the small screen, filters, and fuel line. Check those, but if you try to clean that little screen in the Carb you might as well put a kit in it, it comes with a new screen as well as everything else you need.
That leaning out is also could be a symptom of an air leak elsewhere. This is very often a crank seal and not repairing it will sieze the saw up in a short time. The usual thing is the saw starts to run real good then "unk" siezed. You can check for an air leak around the seals with a can of starting fluid. Spay it on / near the crank seals with the saw running, if the rpms pickup, then you have an air leak, and need to replace the seals. The professional way is to do a pressure and vacuum check but this requires special tools.
PS forgot about the fuel tank vent, you can replace it as well, cheap part.
