Small Engines (Lawn Mowers, etc.)/Yamaha YG6600DEY Generator


Good Afternoon. MY generator will not stay running.(low hours and maintained) It will start up, fine run well for a few minutes then start to run a little rough then stall. it may even backfire through the muffler. If you try to restart immediately it will backfire loudly through the muffler. If you wait a minute or so it will start right up and run for another minute or two. It will not stay running if you spray carb cleaner in carb or loosen fuel cap. I replaced float needle, removed and thoroughly cleaned the carb and fuel tank and fuel valve. Checked spark while running, looks little weak (not sure) but never stops. Removed fuel solenoid and plugged carb. Still shuts down after a minute or 2. Have not checked valves and cannot locate low oil switch or wire to isolate. Did not check keyway.

Even with low hours I would still check the valves.  It is possible the ignition is faulty but it's difficult to troubleshoot.

It is possible you have an air leak, somewhere in the intake system.  When the engine starts to warm up the parts will expand, a little, and it could be a slightly warped intake isolator or gasket.  Did you remove the carb from the engine when you cleaned it?  I am assuming you did but just want to verify...let me know.


Small Engines (Lawn Mowers, etc.)

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Eric A. Jones


Lawnmower Repair . Certified Master Service Technician from B&S. Have 23 years experience on B&S, Lawn Chief, Weed Eater, Echo, Peerless, Wheel Horse, Snapper, Atlas, MTD, McCulloch, Homelite and many other numerous brands. Specialize in electrical repair.


Born and raised in the midwest. Started tinkering with engines when I was about 14 on my Suzuki RM-80. I began lawn mower repair at a small hardware store. I knew absolutely nothing. I read lots of repair manuals and met an older fellow who taught me many lessons. I continued working on small engines through high school and paid my way through college working on mowers at the same hardware store. Decided to get away from the midwest and mower repair so I joined the Air Force. I repaired air traffic control electronic equipment and ended up in Hawaii where I got a part time job at Small Engine Clinic. I gained a lot of experience from the Small Engine Clinic and had a blast repairing small engines. I then took the Briggs and Stratton Master Service Technician test and earned my MST. I then traveled to Wisconsin where I attended the factory update training seminar and received formal training. Continued working on mowers part time as I completed 20 years of military. Retired from the military on a Friday and continued in the lawn and garden industry the next Monday.

MAS Aerospace Operations BA Mathematics AAS Electronic Communications AAS Electronic Technology

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