Onan Emerald Plus genset runs then stops

[damonflyer]

This seems to be historically an issue with Onan. I’ve read so many posts and tried about all of the suggested fixes. It starts fine and continues to run as long as I hold the start switch in. As soon as I release it, it stops. I changed the oil to a heavier weight (10w50), new filter, cleaned carb, fuel tank over half full, filled oil to just touching the tip of the dip stick, fill it to 2/3 full, etc. I haven’t changed the fuel pump since it runs fine when holding the start switch in. Question...does the start switch activate a different fuel pump? All suggestions much appreciated.
MIKE
1997 Damon Intruder 345

[rte154]

Holding the switch in bypasses the low oil pressure and temperature sensors. I suspect one of those two sensors are defective. My 1st guess would be the oil pressure switch. You need to bypass it and then see if it will continue to run.

[damonflyer]

Good suggestion. Since it’s not running at all, I can eliminate the temp sensor. My manual isn’t very detailed and has no diagram showing the oil sensor location. Any ideas where? (Hopefully not internal). If I can identify the temp sensor I’d might as well change it, too. Thanks.

[rte154]

Not sure on your generator but it is usually real close to the oil filter. If it just has one wire attached you can disconnect it and see if it will run that way. This is assuming you have oil pressure. You would not want to run it if there is no pressure.