Generator cranks, but immediately stalls

[Learn2Q]

Friday night, I brought my very first coach home in Alabama from Phoenix, AZ. I know what some of your are going to say, that "I jumped in over my head". That's OK, I can take it. Let me say that I have been traveling nearly full time for the past four years, competing on the pro BBQ circuit. I've been towing a 40' NASCAR style trailer with primitive living quarter, as I like to call them, which means I had no plumbing and a blow up mattress. I did have HD satellite, AC, and a refrigerator. I'm 45 years old and wanted the best I could afford. I'm very happy with my purchase.

I parked the coach Friday night and plugged it in to a 20 circuit at the house. I thought I had everything in the coach turned off to keep it from draining the batteries. I didn't. I have an electrician coming tomorrow to install a 50 amp circuit and connection to plug it in to. Short story, is that after we got home from a day trip to Nashville yesterday it was late, so I didn't go into the coach. I went in this morning and everything was dead. The house batteries had been drained. Little did I know, my household breaker had tripped and quit supplying power to the coach, probably shortly after I plugged it in.

I started the generator, to charge the batteries, with no problem. It ran fine for about an hour. It was hot in the coach, so I turned the AC on (while the generator was running fine). With the generator running, I didn't think that would be a problem. About 10 minutes after I turned the AC on, the generator stalled and quit. It will crank and start, but when I release the start button, it stalls and quits again. I have tried everything to get it to come back on. I have cut everything off on the coach and turned the main power switch off. I have started the coach engine and tried to start it. I have fully charged the batteries and it won't start. It sort of acts like it's out of fuel. The coach has 3/4 of a tank.

The generator is a Onan 12.5
I have two Xantrex Freedom 340 inverters
The coach is a 2006 Travel Supreme Select
All electric - no LP

Any suggestions, short of taking it in to Onan? I do know the generator was recently rebuilt. It has about 1500 hours on it. The coach has 70,000 miles. It has been very well maintained and kept up by its previous owners.
thanks

[jfran304]

I don't know if this will apply to your generator but the Onan generator in our "03" coach had a valve that had to be set for the altitude. When we went from GA to NV we had to set it for the higher altitude and then reset it when we returned to GA for the lower altitude. If I didn't set it, it would start and then quit when I took my finger off the starter button.

Jon

[floridaflash]

I had a similar issue with mine. would run fine till adding a load then shut off and then only run a minute or two. It turned out to be starving for gas due to a kink in the pickup line INSIDE the gas tank. got rid of the kink and now runs like a champ.
David

[bullheaded]

Nice coach...we had an 06 Travel Supreme 42DL14 that with 1/4 tank of fuel or less the generator would not pickup fuel. If that has happened, after fueling hold the Stop button "in" on the Start/Stop switch for a minute to prime.

Guess I didn't see 3/4 fuel...what about a code flashing on the start switch

[gbstewart]

does it have a low oil sender?, if its low on oil it will act up like that
gbstewart

[Learn2Q]

The oil level is fine. On my last Onan generator, when the oil was low, it would give me a flashing error code. No flashing codes are coming up.

[wa8yxm]

Onan generators often are somewhat SMART. Smarter than many people in fact.. They monitor themselves, way better than your average drunk, and if they see themselves "Acting silly" they shut down.

So what's silly

Frequency more than so many Hz off,
Voltage too high, low, or absent.

Those are the big items.. there may be more.

Friend of mine at Quartsite a few years ago, He went to start his ONAN and it did EXACTLY what yours did.. Soon as you released the start button it shut down.. Code said "Low battery or cranking speed too low" which of course did not make sense as we all heard it start.

Thankfully he was parked next to the only two 30 amp outlets in that section of the desert, even if they only were powered up part time (I have 30 amp RV outlets in one of my storage bays,, Long story there but they are a side effect of providing emergency power to my house, for sixteen bucks, I added two outlets for other RV's)

Turned out the brushes were worn and needed to be replaced, That was major surgery requiring removal of the unit from the coach.

NOTE: This is but ONE such thing that can cause a shut down.. There are ways something as simple as a blown fuse or disconnected wire could do it too.

[Learn2Q]

OK, just dropped my coach off a the Cummings/Onan place. They pulled an error code 14. They'll start troubleshooting tomorrow.

[Learn2Q]

New end bell
New rotor assembly
New stator assembly
New radiator

Problems solved
$5,800
It's only money :(

A damaged vibrating end bell can cause lots if expensive problems with a 12.5 onan.

Sent from my iPhone using iRV2 Forum

[justimagination]

Troy, I gotta hand it to you, you dealt with the situation really well, probably better than most. Welcome to the forum, and you made a really good choice, what a beautiful coach. Sure would like to see some inside pics as well. Good luck and travel safe.
David G.........your Georgia neighbor.

[AZgl1500]

Quote:

Originally Posted by Learn2Q New end bell New rotor assembly New stator assembly New radiator Problems solved $5,800 It's only money :( A damaged vibrating end bell can cause lots if expensive problems with a 12.5 onan. Sent from my iPhone using iRV2 Forum

With only 1500 operating hours?
Me thinks that run time clock isn't the original.

I've used Onan generators for years as standby power for microwave towers, none of them ever needed that kind of service. And they have logged a lot of hours over the past few decades.