I just acquired this mower, I know it is a little old but appears to be used very little. It has not been started in a while so I drained the tank, cleaned the carb, cleaned up the spark plug, put in fresh gas, and tried to fire it up. Fingers crossed thought it would run great but Not! So I began trouble shooting - I would pull and pull and pull. Choke on for a while then off. Nothing. Check spark plug for fire - firing fine. Pour gas in cylinder, a small amount of course, put plug back in, pulled - nothing. So I checked the flywheel and amature - rusted very badly. Cleaned with sandpaper, regapped the amature to correct specs - .008 - .010. Same problem - would not crank. Kinda stuck now - don't know if the stop switch, I geuss that's what it is called, is bad or what. Motor just acts like it is not firing. Oh, the carb is getting gas to the bowl. And I did adjust the air-fuel mix screw out 1 1/2 turns out after screwing it in all the way. Any suggestions gentlemen?