Small Engines (Lawn Mowers, etc.): Lawnmower sputters and surges, maintenance checks, airfilter

Question
I have a B&S lawnmower I bought a year ago, when the lawn mower is running and I am mowing my grass, the lawn mower seems to sputter and act like its going to shut off, then sputters on again. I check the gas ventalation cap and it is clean, I checked the airfilter and cleaned it. But the lawnmower still sputters while in use. What would be other maintenance checks I would need to perform for the lawnmower to stop sputtering?

Answer
Hello Parker:

Have you Changed the Spark Plug? Send me the Model Numbers Off the Engine, Please. With these I can Locate the Proper Manual and Better Assist you. I can Be the Carburetor has Trash in the Passages and Requires Cleaning. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John