Small Engines (Lawn Mowers, etc.): mower dies, zama carburetor, zama carburetors

Question
I have a Briggs & Stratton-Murray 20" 3.5 hp Classic throttle free design push mower(274460) I can get it started but it dies about 5 seconds later.  It will stay running if I continue to prime it (flooding)but you can't mow that way.I've changed the spark plug,the oil,the air filter and new gas.And its till won't run.

Answer
Hello Bev:

From your Description it Sounds like the Carburetor Requires Cleaning. The Passages to the Jets or the Jets are Restricted with Varnish that the Gas Forms Over Time.  The Following is a General Instruction File for Carburetor Cleaning. Even though the Carburetor Looks Clean, the Internal Passages May be Restricted with Varnish that Gas Causes to Build Up over Time. I Suggest you Make Sure the Gas is Free Flowing to the Carburetor Inlet Port. If the Gas is Free Flowing to the Inlet Port, then  **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 (if Applicable), Float Pin (if Applicable), Float (if Applicable)  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.*** (Do Not Use High Pressure Air for the Zama Carburetors, they have Check Valves for the Primer and these are Usually Blown Out of the Carburetor if Not Careful. Allow the Zama Carburetor to Set on a Drip Pan and Dry)***. Install New Parts if Required.** You can View a Breakdown/IPL of the Engine at this Site Addy; http://www.briggsandstratton.com/maint_repair/manual_and_more/doclist.aspx?categ... and Enter the Model Numbers (XXXXXX) and Type Numbers (XXXX) in the Appropriate Boxes and Click GO. Then Select Download PDF. If you Hit a Snag or this Does Not Correct the Problem,  I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.

Good Luck

Respectfully

John

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Respectfully

John