Small Engines (Lawn Mowers, etc.): riding lawnmower sputters and stops, steep incline, plug hole

Question
I changed the oil and didn't realize I overfilled a bit. Cut 2/3 of my yard fine, and then the motor just cuts off. It then seemed I had to get the mower level to restart it. It would run a little and then stop again. I drained oil off so that it's at the correct level, and cleaned the spark plug. Sprayed a bit of carburator cleaner in the spark plug hole. Ran fine for a while, and then stopped again. Our yard is hilly and it seems to do this when going up or down a steep incline. What could the problem be?  

Answer
 Hello Cheryl:

 Is the Engine Quiting like it is Running Out of Gas?  Check the Gas Tank Cap and Ensure it is Venting Properly. If yes, then Check/Change the Fuel Filter(if your mower has one). If the Filter is Good, then Remove the Carburetor Bowl and Check the Bowl for Trash. Hope this Helps. I am here if you Require more Assistance. Thanks.

 Good Luck

 Respectfully

 John