Small Engines (Lawn Mowers, etc.): lawn mower repair, lawn mower repair, sears riding lawn mower

Question
I have a 16hp. sears riding lawn mower that won't start, it backfires through the carb. The key is in good condition.Is there another way to check the timing?

Answer
 Hello Russell:

 If the Flywheel Key is Good and you Removed the Flywheel to Confirm this, then Check the Valve Clearance and Check for a Burnt Intake Valve. Send me the Make, Model and Type Numbers Off the Engine, Please. With these I can Locate the Proper Manual and Better Assist you. Hope this Helps. I am here if you Require more Assistance. Thanks.

 Good Luck

 Respectfully

 John