Small Engines (Lawn Mowers, etc.): Chain Saw, stihl chainsaw, fuel mixture

Question
I just got a chain saw from my father in law and he thinks he put straight gas instead of mixed. I have checked the carb and it has a spark. How would I find out if the engine has lost compression or if it is even worht fixing. It is a stihl chainsaw. I appoligize I am not sure of the model number. When I try to get it to start if doesn't even try to start.

Answer
The carb may be bad. The fuel mixture only has oil in it for lubrication, not for performance. In fact, the burning of the oil is the only downside to a two-stroke. Remove the carb and take it apart; be careful with the parts, they're fragile. There are many very, very small parts you have to be careful not to lose. Clean all of the parts, and replace any that look damaged. If you do not feel comfortable doing any of this yourself, then have it done by someone who you know can do it. It sounds like a fuel issue.