HOW TO CLEAN YOUR CHAINSAW PROPERLY Part 1

Not cleaning your chainsaw is probably the main reason saws give up the ghost.
Air is forced through the fins in the Head cooling the fire chamber.  If these fins get plugged the cooling is less and less efficient.
Use a thin screw driver and a wire brush. 

 Then remove the Air Filter and stuff that hole with a small rag.

A compressor sure helps.