Generator was running, then just quit. I have checked all the normal things: gas, spark, has oil (automatic shut down switch), etc. The generator hasn't got many hours on it...maybe 2-3 only. It hadn't been started in a few years, but started right up...ran for a half an hour, then just died. I put new gas in it and it won't start now. It sounded like someone hit the run switch to the off position. Any help would be appreciated