My neighbor was mowing his lawn with his B&S 7hp ohv engine. The engine was running poorly backfiring and sounding like it wasnt developing much power at all. It died and would not start again. When pulling on the cord occasionally it will snap the cord back. I checked the oil which was very low(only on the tip of the dipstick). The mower is only a year old. Could it be a stuck exhaust valve due to not getting oil? What are possible causes for the pull cord being snapped back from your hand?(damn thing gave me a nice bruise). Any responses would be greatly appreciated.

Thanks,
Dave

well, sounds like the valves are outta adjustment. but it ran that low of oil, well make sure its full before you try it again.

Did he hit a rock and almost shear the flywheel key. That will kick back and hurt too.