Onan starts and dies

wa8yxm wrote:
Some modern ONAN generators are "Smart" (modern started late last century)
If the oil is low.. they start but stop when released
Same if the oil is old or dirty

If they are not putting out 120VCA or darn close to it Why waste gasoline shut down. Several other failure modes will shut it down

What is the error code? NOTE code may be cryptic.. one of the above named faults reads out as "Low battery or speed not fast enough"

Oil low sensor will turn off the ignition and that results in immediate shut down. OP has attempted spraying starting fluid into the carb and the engine will run a few more seconds longer with each spray.. To me that indicates that the ignition system is still live and functioning.

Op has mentioned something about the oil sensor being disconnected which might even rule it out depending on they style of sensor, some make contact with low oil and some make contact only with oil level high enough..

But as I mentioned ignition obviously is staying on if a spray of starting fluid keeps engine running a bit longer with each spray.

As far as dirty oil shutting it down, thats a new one for me, have never seen that in small engines or even automobile engines..

Even with the fuel pump shutting off as the engine dies, that to me is not the problem. The fuel bowl contains more than enough fuel for the engine to run on for minutes.. As my standard procedure for storing my gens I turn off the fuel supply valve while the engine is running. This allows the engine to drain as much fuel as possible out of the bowl. Typically it takes 2 minutes or so before the engine starts "hunting" for fuel, I can close the choke some and the engine will run several more minutes..

OP most likely has a clogged carb jet and emmulsion tube. Not familiar with Onans carbs and how easy it is to remove and clean the parts.

On Honda designed carbs the jet is screwed into the same place as the the screw that holds the fuel bowl on.. Remove the fuel bowl and with a flat blade screw driver you can unscrew the jet. On Hondas there is a brass tube that the jet holds in place. That tube is where all of the problems are, that is the emmulsion tube. Is has a bunch of tiny little pin holes on the side of it. It only takes one of those holes to get partially plugged and the engine doesn't run smooth anymore..

I suspect the Onan carb is of similar nature, but my understanding is Onan discourages people from trying to tear them apart to fix..

OP doesn't seem to have much knowledge about engines so a replacement carb may be the route IF they can find a replacement..

I have never had any luck with cleaners you put into the gas with Honda carbs, I always have to remove the emmulsion tube and hand clean it with a sewing pin..