Small Engines (Lawn Mowers, etc.): Engine will not run, briggs and stratton, gas tank

Question
Hi John
I am working on a MTD 12AE459F372 21" 6.0 lawnmower B/S engine.
It was running find until I ran out of gas. I refilled the tank and started the engine but it only ran for about 10 seconds. I did that a couple of times. I replaced the plug and cleaned the air filter that was very dirty. Now it will not stay running I cleaned the carburetor bowl but that did not help
I removed the spark plug and it was wet with fuel, when it does start it will only run for a few seconds. The engine is on a yard man 21” lawn mower and is about 5 years old do you have any ideas on what I should be looking for?
Thanks for your help
Barney7690@yahoo.com  

Answer
Hello John:

Usually this Problem is Caused by the Sediment in the Bottom of the Gas Tank Being Sucked Into the Carburetor Passages and Restricting the Gas Flow to the Carburetor Jet. You can View a Breakdown/IPL of the Engine at this Site Addy, http://www.outdoordistributors.com/ and Select the B. Then Select Briggs and Stratton. Then Select Don't have Part Numbers. Then Select the File #12.  Then Select the Folder #12H800. This is the Model Series Engine Listed for your Mower. I Suggest you First; Remove, Disassemble and Soak the Carburetor Overnight in Carburetor Cleaner (I use Gunk). Then Blow Out the Passages with Compressed Air. Install a New Kit if Required. Hope this Helps. I am Here if You Require More Assistance. Let Me Know What Happens, Please. Thanks.

Good Luck

Respectfully  

John