Generator went into over speed today when it was starting for it's weekly test. What could have caused this and what is the solution? It is a 14KW Model 0058841 Generac Automatic Standby Generator.

so repair it before you get injured -dont use it till repair done

what is the filter part number on the Generator now? Give that to an Auto parts place and they will cross it to what they sell

Assuming the generator circuit breaker is on, depending on the model it could be the voltage regulator or the slip ring brushes or both. If it's a portable it could be a capacitor problem.

It definately sounds like a fuel problem, lack of fuel..I assume it is running on LP or natural gas. The hose running from the demand regulator goes to the carburetor/mixer. When it gets to the carburetor, there is an adjustable main jet. It is different on different models, but is usually easy to find. There is probably a screw slot in the end of the screw head and a spring under the head. Start it up after locating the screw and open the jet just enough to even out the running. It was factory set, but barometric pressure and altitude and different fuels in different areas will decessitate different settings.
Please let me know if this fixes your problem, Robert

DID YOU HOOK IT UP FOR120 VOLT OR 240 VOLT

The battery charger is defective, as you can start it by jumping it off means it is just a low battery. without it running measure battery voltage, it should be around 12V then plug the charger back in, it should climb to around 13.8B with a good battery. If not have the float charger checked.

Is the outside air temp cold. These generators will backfire if it is real cold and if the propane pressure is low. It is suppose to be 11 to 12 inches of water colume at the generator fuel input. drygwals

test fuel pump pressure seems like its faulty i think your right

si tiene transfer automatico solo poner un swicht en hilo 1N para cortar senal de entrada al generador del utility power que sensa la presencia de voltage en caso de falta arranca el generador en forma de prueba