Small Engines (Lawn Mowers, etc.): B & S shuts off when turning blades on, crankcase oil, gas leaks

Question
I have a Briggs 17hp troy built rider and it started blowing white smoke. I took the engine partially apart and looked at it. I noticed gas flooding the exhaust. I can start it and ride around yard but when I turn on the blades the engine dies. Any ideas what might be causing this? Thank you in advance, Rich

Answer
Hello Rich:

This is Caused when the Carburetor Needle Valve (also called the Float Needle) is Not Seating Correctly and the Gas Leaks by the Needle and Floods the Carburetor and Cylinder. Check the Crankcase Oil. Does it Smell like Gas and is Over Filled? If Yes, then the Carburetor Needle Valve is Allowing Gas to Leak by and Flood the Cylinder when the Engine is Not in Use. Change the Oil. Make Sure to Drain the Engine Good. Refill to the Proper Oil Level and Install a Manual Cut Off Valve and Manually Turn Off the Gas When Not Using the Mower. If the Carburetor Needle Flow Valve Leak is Not Affecting the Engine Operation, then you Do Not Need to Clean and Rebuild the Carburetor. When the Leak Starts to Interfere with the Engine Operation, then you Will need to Clean and Rebuild the Carburetor. I Say this Because I have Done So Many that a Clean and Rebuild will Usually Last a Few Months and then the Same Condition Occurs. The Manual Shut Off Valve is the Only Way I have Found to Stop the Flooding of the Crankcase when the Engine is Not in Use. In Your Case the Flooding Carburetor is Interfering with the Extra Load the Blades are Putting on the Engine. 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. Have a Happy Holiday Season and May the All Mighty Bless You and Yours. Be Safe and Happy. Thanks.

Good Luck

Respectfully

John

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Respectfully

John