Small Engines (Lawn Mowers, etc.): 4HP Briggs and Stratton engine sputters, briggs and stratton, d drain

Question
Allen,

I have a Yarb machine with a 4HP Briggs and Stratton engine.  It was running fine for about an hour and then it started to sputter and hasn't stopped. It starts fine but never gets up to speed
I cleaned the Spark plug, cleaned the Carburator out with small engine carb cleaner, Cleaned the air filter... replaced the oil...

What am I missing?
Thank you for any help you can give me

Answer
Hiya Scott-
Sounds like some good checks you've made- next I'd drain the gas tank, and drop the fuel bowl if it has one (sounds like some water in your gas.
Do you know if it has points?  If so- that could also be your problem.
Another thing to check- make sure your choke linkage is ok and not bent- damaged or loose.  A choke plate in the wrong position or not opening fully will also cause the symptoms you have.
Lemme know K ?
CYA