Small Engines (Lawn Mowers, etc.): back fire through out the carberator, carberator, valve clearance

Question
I have been working on a 14hp briggs ohv. I found the intake pushrod was been bent, I have set the springs on the vales around .03 to .05 the engine will not fireup,but will backfire through the carb. I did change the flywheel key,is there any way that the cam gear could have been bent? I cant under stand why this engine or me cant find the timing. I did the tdc with the piston and back off about one inch, can you help me?  thanks larry Ellis anlome5805@aol.com

Answer
Hi Larry,

I would say that the intake valve is either opening early or is leaking.  Check the valve clearance to make sure the valve is closing and seated.  The timing gear may be one tooth off or the crankshaft may be bent.  The ignition timing could be too advanced but that would usually produce a kick back.

Good Luck and let me know how you make out,
Michael