Briggs & Stratton lawn mower?

No. Most likely, the speed govenor is either incorrectly assembled, or the spring is snagged. If the problem is internal, the only answer is a complete stripdown. If it's an air-vane type, it has to be a snagged/jammed spring or linkage.

Cam timing problems usually just cost power. It it's more than a couple of teeth out on the cam cog, it just won't start.

(phil_saunders(a)bigfoot.com)

Phil Saunders
June 2013