Onan Generator 7500 Quiet Diesel

DANO2014 wrote:
Having problems with my generator, Onan 7500....runs OK until I turn my A/C on. When it loads up the generator will run about 5-10 minutes and kill.
I am getting three blinking lights on the switch after stopping. According the manual it mentions abnormal maintanence problems. I will bring it to a Onan dealer in the morning but was checking on any suggestions available information from those that may have experience these issues.

DANO2014,
Ok, you're seeing "Blinking" lights on the switch after the engine shuts down. Those blinks are telling you a code. The code is deciphered by counting the amount of blinks you see, then, there's a short pause in the blinks then, there's anther set of blinks.

Then, there's a long pause, and the whole sequence starts all over again. So, first off, how many blinks in the first series, then, after the short pause, how many more. If you count say, three blinks in the first set, then the short pause and, three blinks again then, the long pause, you'd have "3 and 3". That would represent a code 33. In the trouble shooting book for Onan, there's a list of codes, what they all mean, and, possible remedies for each code. On my coach, an '04 Itasca Horizon 36GD with the C-7 330HP CAT, we also have the 7.5 QD diesel gen.

About two years ago, it did the same exact things yours is presently doing. When I checked the codes, it came up as "over heat condition" and, in the book, it had several remedies. All of which were not the cause.
What it ended up being was a very common cause of that code "33" (three blinks, short pause, 3 blinks- long pause, start over), and that was the infamous "TEMP SENSOR" that's located in the thermostat housing in that little Kubota 3 cylinder, 14HP diesel engine.
It's been known to cause all kinds of operational issues.

Now, does this mean that, that is your cause, not sure but, you'll have to decipher the code, to start. Good luck.
Scott