Small Engines (Lawn Mowers, etc.): Tiller will not start, diaphragm spring, head gasket

Question
I have a craftsman tiller with a 5hp B&S engine.  I had to replace the fuel tank because of the contents inside was rotten.  I cleaned and soaked the carb, also replaced the needle valve, diaphragm spring and gasket.  I also replaced the intake valve because it was damaged due to a wrong spark plug, new head gasket.  I checked the spark with and without a spark tester, and get great fire.  I crank and crank, even prime the engine buy pouring a tiny bit of fuel into the cylinder, still no start.  I did get a blue flame out the exhaust when I did this.  I refuse to give up!  Advice would be nice. Thank!

Answer
Hello Chris:

Did you Lap In the New Valve? If No, then that Can be a Possible Cause. The New Valve Mating Surface Does Not Match the Valve Seat. Lap the Valve and Rest the Valve Clearance. Have you Checked the Flywheel Key? If the Flywheel Key was Damaged when the Valves was Damaged, then the Plug is Firing Out of Time. The Cam Times the Valves and the Flywheel Key Times the Plug. Send me the Model and Type or Spec Numbers Off the Engine, Please. With these I can Locate the Proper Manual and Better Assist you. You can View a Breakdown/IPL of this Engine at this Site Addy, http://www.smallenginepartswarehouse.com/parts.asp and Select the Shop Online Parts Look Up. Then Select the Model Tab. Then Select the OEM and Enter the Model and Type Numbers (first 4 digits Only). Then Double Click on the Model in the Results Area. Now you can Select the Section of the Engine you Wish to View. If you Hit a Snag or this Does Not Correct the Problem,  I am Here if You Require More Assistance. Hope this Helps. 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 8pm EST (US). My New Day Starts then. Thanks.

Respectfully

John