Small Engines (Lawn Mowers, etc.): Craftsman 19.5 HP Riding Lawn Mower, carburetor body, internal passages

Question
I have a 97-98 Craftsman 42" riding Lawnmower with a 19.5 hp twin cylinder motor, model number 917.270810.  If the Choke is fully out it will generally start and then die a few seconds later.  You can repeat this process all day but it will never start and stay running longer than 10 to 15 seconds.  To me it acts like it is running out of fuel but being able to repeat the process after a few seconds doesn't support this.  I have rebuilt the carburetor, replaced the carburetor with another one and the same problem still happens.  It is unlikely that two carburetors would have the same fault, at least in my mind.  Any thoughts on where I can look next to get this working?

Answer
Hello James:

Can you Spray Short Bursts of Starter Fluid into the Carburetor Throat and Keep the Engine Running? If Yes, 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, 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 Accidential Spillage. Then Blow Out the Passages with Compressed Air. Install New Parts if Required. Soaking the Carburetor is the Only Way to Endure the Internal Passages are Clear. Was the Other Carburetor Setting A While? If Yes, you Could Have the Same Problem with it as Well. What is the Cylinders Compression? Is the Gas Free Flowing to the Fuel Pump? Is the Gas At the Fuel Pump. Some Models have to be Primed to Start. The Vacuum Fuel Pump will Not Pull the Gas to it Once it is Dry. Go to this Site Addy, http://www3.sears.com/ and Enter the Model Numbers in the Upper Left Search Box and Click Go. Then Visually Verify the Equipment and CLick Continue. From this Page you can View Diagrams or Parts Lists for you Equipment. Hope this Helps. I am Here if You Require More Assistance. Let me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John

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Respectfully

John