Small Engines (Lawn Mowers, etc.): B&S 20hp Engine problem, carburetor body, adjustment screws

Question
I have a 20hp B&S on my riding mower that is having problems model and part number
460777 – 2277 E1.  

If I keep the choke at full open it will run.  Once I close the choke it will continue until the valve throttle opens, then it starts to die.  If I pour gas in to the carburetor it will keep running.   
If I move the throttle from fast to slow, I then can close the choke and the valve throttle remains close and it runs fine.  Once I move the throttle from slow to fast and the valve throttle opens it dies.  

I replace the fuel line and fuel filter.  Replace the gas with fresh. Still no luck.


Answer
Hello Steve:

If the Gas Line to the Carburetor is Clear, then the Cause of this Problem can be Either the Fuel Shut Off Solenoid in the Carburetor Base or the Carburetor Requires Cleaning. 1- The Solenoid: Remove the Carburetor Solenoid and Go to the Hardware Store. Purchase a Bolt of the Same Diameter and Threads. It Needs to be 3/4" Long. Put this Bolt in Place of the Solenoid. If this Corrects the Engine Problem, then Replace the Solenoid. ***NOTE: THIS IS FOR CHECKING THE SOLENOID ONLY I NEVER SUGGEST YOU OPERATE THE ENGINE WITH THE SOLENOID OUT OF THE CARBURETOR EXCEPT FOR TESTING PURPOSES*** Sometimes the Plunger is Moving, Just Not Far Enough to Allow the Gas to Enter the Jets. 2- The Carburetor:  Remove, Disassemble and Soak the Carburetor Overnight in Carburetor Cleaner (I Use Gunk). I have Found that Most People can Use a Breakdown/IPL and Disassemble the Carburetor Enough for Proper Cleaning. You Only have to Remove the Bowl, Float Pin, Float and Needle Valve and Any Adjustment Screws that Go Into the Carburetor Body. The Welch Plugs Do Not have to be Removed. Then Soak the Carburetor Body and Parts in a 1 Gallon Can of Gunk Carburetor Cleaner Overnight. The Can has a Parts Tray Inside it for the Small Parts. Once the Carburetor and Parts are in the Cleaner, you can Replace the Lid for Safety and to Prevent Accidental Spillage. Then Blow Out the Passages with Compressed Air. Install New Parts if Required. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 9pm EST (US). My New Day Starts then. Thanks.

Respectfully

John