Onan Generator Issue

[sammywolfordwv]

On our last trip our generator stopped working after 10 minutes and then we could not get it to start again (luckily, we brought our new back up generator). We have changed the filters and replaced the fuel pump. Any other ideas why it won't run? Thank you

**edit** We had this issue a year or so ago and replaced the pump then. It worked fine and then all of a sudden it stopped.

[Chuck v]

Most Onan generators for RV use have low oil level cut-out switches, so check the oil level. As with any gas engine -- check fuel, spark, and compression...


If this is a large RV Onan genset that is diesel fueled, also check for any air in the fuel lines. Compression tests on a diesel requires a special gauge, since the pressures are much higher than an automotive gas engine...



Chuck

[sammywolfordwv]

Thank you. We just serviced it before we went out. It could be in the gas, but we just thought there might be another issue that is common.

[djdoc]

I had the same issue and found it was the fuel pump. It would start and run for 10 to 15 minutes then stop. After sitting a while it would start again but only run for 10 to 15 minutes again. Apparently the fuel pump was heating up and shutting down. When it cooled down it would start again but only run til it heated up again. Changed the fuel pump and it has been running fine since.

[RY469]

You can pull the fuel line off and push start switch to the off position to see if the fuel pumps properly (into an appropriate container). This will tell you if the fuel pump is an issue. At that point see if the fuel cutoff solenoid (bottom of the carburetor) has 12vdc to turn it on. The oil pressure sensor switch mentioned earlier is also an issue, should be in closed (making contact, continuity) position, this is tied into the aforementioned fuel cutoff solenoid. Maybe not an electrical issue after this point if all well with these things.

[Bmoe]

Reply to Oman issue
My Oman 5000 will cut out intentionally when my main gas tank reached 1/4 full level.