Understanding the MODEL number.

One of the things I run into often is the lack of information provided by the owner of the generator. One thing that is needed by any generator technician is the FULL MODEL NUMBER. Sorry to yell. It is frustrating. I know a lot about these generators by heart. What I don't know is which one you own. Please, always start a question or comment with the model number of the generator in question. Let me give you an example of how to identify the model number.

The section marked "Model No:" is the model number. The serial does not help me but the model does. The first 3 to 4 characters tell me what series generator you have. The very last letter, this is the most important. This is the specification (spec) letter. From the model and spec I can determine every part that is inside your generator. The rest of the tag shows some very useful information but it is not necessary to relay this info.
Most places will not even talk to you without a model number (Onan) but I will do my best to try and help you figure it out.
I understand that over the years these tags can get ruined, painted over, destroyed and misplaced. It happens. I have seen my share. If this is the case for your generator, all is not lost. At this point we need to identify some part numbers inside the generator. Luckily, because of having so many part numbers for different models, I can use these to identify the generator. If you don't have a legible tag, please take the time and remove the control board (located behind the START/STOP switch). The control board will have a small bar code sticker on it and a very small number printed underneath it. This is the identifier. We can now assume the model of generator and get within a few letters of the proper spec.