While mowing hit a object and engine stopped. B&S 18.5 two years old. First thought was timing. Pulled flywheel and key intact. Adusted the valves(ohv) 1/4 past tdc as specified.
.003-.005 and .005. Spark pluk fires and is getting fuel, but will not start. I amd not an expert, but I have worked on a few mowers in my time and this one has me baffeled. I need some EXPERT advice. HELP and thanks in advance. chuck35

I am the official expert lawnmower killer (just ask my son). I successfully killed 3 lawnmowers in 2 weeks mowing over my cast iron lawn hose guides (decapitating them actually). I successfully bent the shaft on ALL the mowers. Honey, you bent the shaft. I should know - I'm the expert lawnmower killer.

Did you go 1/4 turn or 1/4 INCH past TDC? The correct procedure is 1/4 inch past tdc. When you tightened flywheel nut, if you do not properly torque the flywheel, the key can shear before it ever starts the first time.