Onan 10K in my 2007 Beaver Contessa. Spiratically misses or surges. One day will run 5-6hrs with no issues, next day surges/misses. No codes. Can vary between 1hr and 3hrs before misses/surges when it does. When running will support 2 AC and Microwave with no problems. Tightened fuel lines, ran Generator from One gallon diesel jug and still missed/surged. Changed fuel filter, changed air filter, and changed coolant. Checked hoses and air flow fittings with no obvious issues. Now just changed thermostat and temperature sender and still surged. (changed because once it did throw a temp code) Reset and no further codes sent. No loose electrical connections. Pulled out Governor actuator/solenoid - opened/closed freely under 12V power. Ohms checked test above limit. Runs cool.
Any more suggestions or ideas, please let me know. Called Onan Service Center and they only want to set up an appointment no suggestions. Budget isn't open to that right now.
Thanks, Randy