Kohler backfiring

[pwelch870]

I have a Craftsman lawn mower with a 16 hp Kohler engine that is backfiring through the carburetor. Any suggestions on what is causing this?

 

[bertsmobile1]

Either the timing key in the flywheel is broken or the inlet valve is not fully closing

 

[Russ2251]

...possible bad plug or lean fuel/air mix as well.

 

[mikebarber]

If exhaust is restricted a bunch you will get a carburetor backfire because some of the exhaust stays in the engine If the Kohler 16hp is overhead valve I would pop a valve cover and check valve action Check both valves when you have cover off

 

[Rivets]

If it would be a Kolher Courage engine I would be looking at either valve clearance and/or timing.