I bought this mower used, although not used much, and used it last summer myself. It ran fine but in the fall got hard to start. I thought the starter was bad after replacing the solenoid and replaced the starter. Still it would not turn over enough to start. I pulled the flywheel and checked it for damage, it is fine. With the plug out it turns great and I can hear compression release. I am assuming that it is not enough and maybe a cam is the problem. Any thoughts from anyone?