Small Engines (Lawn Mowers, etc.): craftsman ltx 1000 riding mower, craftsman ltx 1000, model number

Question
Hi and thanks ahead for all your time and expertice.  I was mowing today with my Craftsman ltx 1000 mower and all of a sudden it sounded like I hit something and then about 10 seconds later, it dies.  I've checked over and under and nothing is broken or bent or loose that I can see.  I turn the key and it wants to start but I just get this loud whirring noise and it won't turn over.  Please help.

Answer
Can you send me the mower model number located on a sticker near the rear of the mower, maybe under the seat.  I need the model number, xxx.xxxxxx, to look up your engine.

Will the starter spin the engine?  Have you checked to see if the engine is producing spark?

Let me know.
Eric