7.5 Onan Diesel Generator

[2000_American_E]

My Onan Generator is currently shutting down after running for a short time. I have had problems with this generator in our 2000 American Eagle since we purchased it in 2017. I had 210 hrs when we purchased it in 2017 and now 325 hrs. I had a very qualified technician check it out and replaced the control panel in 2017. I turn it on several times a year, load it up and it has been working most of the time. It seems to shut down when I need it. The code was 33 coolant high temp. I have changed thermostat, radiator cap, sensor, fuel filter, air filter. it is still shutting down with code 1 high temp. Any suggestions?

[Shot-N-Az]

https://www.youtube.com/watch?v=0LB5ZhvhXas&t=146s

[hypoxia]

Have you pulled the coolant fill hose with the radiator cap out and extended it above the top of the generator and topped off the coolant?

[Cloud_Dancer]

It could very well be mineral deposits inside the cooling tubes of the radiator. That's what it was on mine (same model of generator on my 2003 Dutch Star). I removed the radiator and took it to a radiator shop for a complete cleaning procedure. The problem never came back.

[Flute_Man]

How about the radiator or the fan? Does it overheat on no load?

[bobsallyh]

2000 American Eagle, can't help with the diesel Onan, we have a gas POS. Onan's are like an old woman, lot's of TLC!