Small Engines (Lawn Mowers, etc.): mower vs tree root, exhast, tree root


Question
My son hit a tree root while mowing, mower shut down and he stopped mowing. I replaced the bent blade and the mower was hard to start, once started it smoked alot, smelled of oil. I ran it for a few minutes, stopped and ran it a while longer, looks like oil coming from exhast. What could be damaged?

Answer
I don't believe hitting a tree root could make the mower start burning oil, if you turned it up on it's side, oil could have ran into the muffler out of the engine. If this is so, it usually takes a while to burn it out. I wonder if you sheared the flywheel key or bent the crankshaft.