Small Engines (Lawn Mowers, etc.): ran over stump mower wont start, craftsman eager 1, dirt pile

Question
i hit a couple stumps and a dirt pile with a craftsman eager-1 5.0 hp mower.the blade nut came loose and it stalled. it wont start . i have good spark.when i pull the start cord it pulls back sometimes.

Answer
Either the blade is loose, the blade adapter/key is sheared or the flywheel key it sheared.

Before you spend a lot of time on it you should check for a bent crankshaft.  Remove the spark plug.  Have a helper tilt the mower up; I usually have my helper stand on the mower handle to keep the mower up.  Make sure the engine shut-off cable it also held in place and then have the helper pull the string while you observe the blade under the mower.

If the blade appears to wobble then the crankshaft is bent and it's probably not worth fixing...you will have to replace the crankshaft.

Let me know what you find.
Eric