Small Engines (Lawn Mowers, etc.): mower runs for 30 secs then acts like it runs out of gas, carburetor body, internal passages

Question
i have a craftsman push self-p 21" model#917.378922
ran fine till i change the oil and put the mower on its side (carburator down for abought 5min.) it runs fine for a min. then runs out of gas i think.push red bulb pull string and runs again for min or so then dies....i have taken the carb off and the bowl off..plan to get cleaner and spray carb for a while to see if that will help....please let me know what you would do  step-by-step :)   do i need to get a new red bulb piece aswell

Answer
Hello Patrick:

Spray Cleaners Usually Do Not Work. Even though the Carburetor Looks Clean, the Internal Passages May be Restricted with Varnish that Gas Causes to Build Up over Time. Spray Cleaners Clean a Layer of this Varnish. A Good Soaking is Required to Properly Remove the Varnish Completely. 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. Install New Parts if Required.** If the Primer Bulb is Damaged when Removed for Carburetor Soaking, then Replace it. Otherwise Just Soaking and Cleaning wiil Correct the Problem. 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