Small Engines (Lawn Mowers, etc.): Murray 18 HP I/C OHV will not start, briggs and stratton, crank shaft

Question
I was cutting grass the other day when my lawn mower made a loud bang and smoke came out of the engine. I went to go check the oil dipstick and smoke came out of there.  After 10 minutes we went to go start it again, and it did not start and it made a click noise, and the engine would not turn over.  A day later, i played around with the crank shaft, and now the engine will turn over, and starts to vibrate.  My model number for my Murray 18 HP I/C OHV Briggs and Stratton engine is 425000x8.  Any suggestion or help on how to fix this problem will be appreciated.
     Thank You

Answer
Hello Joe:

Send me the Model Numbers Off the Engine, Please. With these I can Locate the Proper Manual and Better Assist you. The Model Numbers you Sent me are for the Mower. Go to this Site Addy, http://www.smallenginepartswarehouse.com/parts.asp and Select Shop Online Parts Look Up. Then Select the Model Tab. Then Select the OEM (Murray) and Enter the Model Numbers (40508X92D). Then Double Click on your Model in the Results Area. Then Select the Section of the Mower you Wish to View. A Connecting Rod May have Broken. Check the Compression. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 9pm EST (US). My New Day Starts then. Thanks.

Respectfully

John