RV Repair: onan 4000 generator 4.0KY-FA/26100H, electric switch, level sensor

Question
Motor will not start, I wants to, but as soon as it starts to run,or tries to run, it shuts off or down. Think it is a censor problem. Oil level, City electric generator electric switch or something. could you help  

Answer
Hi Scott:
Oil pressure or level sensor is a possibility. Both those sensors are bypassed in the start position. Keep the start button pushed down when it tries to run and see if it will go then. The starter will kick out even if you hold the button down, different from your car. If it stays running then one of the safety sensors is bad. If it does not then you probably have a carburator/fuel/choke problem. Good luck.
Bill