Small Engines (Lawn Mowers, etc.): Briggs & Stratton 15.5hp OHV engine, briggs stratton, safety switches

Question
Hi,
I have an older(1989)Mastercraft riding mover that had the engine fail. I purchased a remanufactured replacement engine on ebay. The numbers are 28N707 1036R. I have adapted the wiring to work with the newer generation of engine ie: 12v to carb solenoid and switched gnd to coil to shut off.
Problem:
When initially starting the engine it started right up and ran for about 3 minutes then I shut it off, but then never started again.
Now when attempting to start it cranks quickly to compression and nearly stalls but the completes the revolution. I have confirmed all wiring, replaced the solenoid with good solid grounding, fresh battery (tried car battery direct to starter with same result), had starter checked it 2 different shops and I checked it too the brushes are like new and comm is clean. New coil, fresh oil, checked all safety switches for proper operation. Pulled flywheel bolt and checked upper key for damage and found none. This engine has never even had belts on it. Per the manual I put a torque wrench on the flywheel bolt set for 30lbs and was able to rotate the entire assembly with compression through completed rotations without coming anywhere near 30lbs. I have checked and reset valve lash to factory specs and then tried a little tighter at .005.
If I remove the sparkplug it cranks just fine but just doesn't seem to be able to crank properly with compression.
Please help if you can, I have no idea what else it could be. I have rotated the engine by hand and the valves seem to open and close correctly ???

Answer
 Hello Mike:

 I Set the Valves on Briggs as Follows: Set the Engine to TDC. Then Set the Intake to .003in - .005in and the Exhaust to .008in - .010in. I have Tried to Set them According to Briggs Instructions and have the Same Problem as you Each time this Procedure was Performed. Since I have Started Setting them My Way I have had No Problems. I have Found Out that If the Valves are Not Set Properly, then you have the Starting Problem You Described. One Thought! Did you have the Starter Load Tested or a General Starter Test? Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.

 Good Luck

 Respectfully

 John