Hello, my name is XXXXX XXXXX I am going to try and help you. I am certainly not trying to scare you, but there are a few caveats that you need to be aware of up front. Very few portable generators are made here, most of them are overseas. Even the so called name brand gensets like McCulloch and HomeLite are not made by these companies, they are outsourced. As a result, manuals, schematics, helpful service and even parts can be very difficult to come by.
Do you have a good multi meter and know how to use it? It will be absolutely necessary to have one. Are you comfortable with removing and replacing wires?
Without a schematic, these types of gensets are difficult at best to troubleshoot when I am actually looking at it. This difficulty is compounded by not knowing what you are seeing.
Also, it would help if I had the model number. Do you have an owners manual? If you do, please read everything in it and see if you can find any reference to the words 'brushes, brushless, PMG, permanent magnet or fixed magnet'.
I assume the engine side is running OK. Have you tried resetting the circuit breakers?
How many and what type of outlets are on the control panel? Are there any guages or meters on the panel? I need you to be as specific as possible.