what should i use for the head gasket on my ryobi. i no the local autoparts stores sell gasket material but they have different types such as cork and rubber so what should i use?
Probably doesn't have a "head". Every chain saw I have ever seen the cylinder and head were all one piece. All you need to do is make a gasket out of a gasket material that is resistant to fuel and you will golden. Smear some grease on the bottom of your cylinder and then set it on your gasket paper and cut the resulting grease outlined shape.
I would go with sealant if you can. I couldnt find motoseal, and grabbed Permatex Copper and havent had any problems with it. I know a couple other guys here use it. My local parts store does sell some standard gasket material, I cant remember who makes it but Ive had good luck with it on motorcycle cases and what not.
Sealant alone is OK provided it doesn't make the squish band too tight. I've deleted the base gasket on some saws, but needed a thin gasket on others to get the .020"-.025" squish I was trying for. Too tight and you're asking for detonation if the piston clears at all, and too thick of gasket you lose compression.