It will barely even run, when it does it just spits and sputters unit it stalls out. I was originally thinking I had carb issues so I replaced it and its still acts the same way. I also pulled the valve covers off and they look to be opening and closing properly as far as I can tell without tearing it down more. Also verified the key was in the flywheel.Sounds like it might be running too lean, and might be getting to much air in the intake. How easy does it start when the engine is warm?