Will a sheared flywheel key cause a lawnmower engine not to spin?

My riding lawnmower just broke while i was mowing leaves. I've rebuilt lawnmower engines before, and I'm fairly certain the piston rod broke, but i couldn't remember what the symptoms of a sheared flywheel are. Would a sheared flywheel key cause the engine not to rotate when you spin it by hand? It will move an inch or so and then stop like it's hitting something.


Like i said, i'm fairly certain something broke inside the engine and that it cant rotate because it is hitting the part... but wanted to check anyway to see if a flywheel key might do anything like this.



It shut down about 45 seconds after i hit a big stick or something with my blades, and i know that is what can shear a flywheel key... but it might have just been coincidence that it stopped shortly after hitting something... or that jolt might have caused the internal parts to fail.