Onan 400 gas generator

[Notsoaverageguy]

So I have a Onan 400 generator in my older motorhome that I am selling, its in a 1996 fleetwood Jamboree. We have owned it for 7 years and it has been somewhat tempermental. I will explain, besides the yearly cleaning out the carb when you start it up its hit or miss whether it will stay running and does not always put out A/C. So if I go to start it and with my finger on the start button if the Tachometer starts clicking away I know everything is fine and the microwave beeps to life. But if the tach doesnt click away and the microwave doesnt come to life it will quite the second I take my finger off the start button. With my finger on the button it will run as long as I keep it on the start button. Whats up?

 

[Kevin D Pem]

Check the 12v relay in the generator compartment

 

[Notsoaverageguy]

Check the 12v relay in the generator compartment

Yeah I went down this road a couple of years ago and replaced it. BUT at your request I checked it. No voltage to either of the big terminals till I start it then Volts on both sides.

 

[Kevin D Pem]

Not the starter relay. There is a relay that is used to maintain the momentary switch state for coil voltage. That is what makes multiple start switches a possibility. It looks like the relay used on older car headlight relays.

 

[Kevin D Pem]

Readily available at any Auto parts store.

 

[TheLooks]

Also, holding the button in bypasses the multiple reasons it will not run. Onan's have a million sensors that shut it down and pushing the button and reading the flashes tell you the code. Google it. It shuts down as soon as you release it because the code is set until fixed.