No 120v power from Generator

[Keith in a Flair 22]

I have a 2014 Itasca Sunstar with a 4000 Onan generator. Previously, while boondocking, when I needed 120v power, whether for microwave, A/C, or just a hair dryer, I could run the generator to get it.
I fired up the generator today, let it run for 10 minutes, but ever got any indication of 120v power.
As a test, I plugged it into my house power (20a connection) and everything 120v worked like normal.
I haven't looked into this in earnest yet; I thought maybe someone on this forum might have the answer right away.
Any thoughts as to what I should de first?
TIA,
Keith

 

[NY_Dutch]

Check the circuit breaker on the generator. If it kept running, then at least it's generating electricity. If there was no generation at all or very low voltage, the engine would not keep running once the start button was released. The onboard circuit breaker is the most likely culprit, and the next most likely failure point would be the automatic transfer switch.

 

[DonTom]

Does your shore power cord need to be plugged into the generator outlet? I have made that mistake a few times and wondered what was wrong.

-Don- Reno, NV

 

[Old_Crow]

Check the circuit breaker on the generator. If it kept running, then at least it's generating electricity. If there was no generation at all or very low voltage, the engine would not keep running once the start button was released. The onboard circuit breaker is the most likely culprit, and the next most likely failure point would be the automatic transfer switch.

Not necessarily true. When my Onan 5500's stator went out, the genny ran just fine,. just made no electricity. I ended up swapping for a 7k genny I bought from an RV salvage yard.

 

[NY_Dutch]

Not necessarily true. When my Onan 5500's stator went out, the genny ran just fine,. just made no electricity. I ended up swapping for a 7k genny I bought from an RV salvage yard.

Your 5500 must have been different than my 5500 Emerald BGE for instance. By design, it won't keep running if the output voltage is below about 60 volts when the start button is released.

 

[Old_Crow]

Your 5500 must have been different than my 5500 Emerald BGE for instance. By design, it won't keep running if the output voltage is below about 60 volts when the start button is released.

Possibly. I'm sure it was the generator that came with the coach(I'm only the 2nd owner)and it's a similar vintage to yours, so I would expect a similar model, but it ran just fine...several times, just no power output.

Tech told me the stator was burnt, quoted me $2300 to fix it. Generator also had motor problems(smoked and used oil). When those additional repairs were added into the mix, the quote quickly went over the price of a new one.
I took another alternative and found a good used replacement in Phoenix, at Arizona RV Salvage.

 

[NY_Dutch]

Possibly. I'm sure it was the generator that came with the coach(I'm only the 2nd owner)and it's a similar vintage to yours, so I would expect a similar model, but it ran just fine...several times, just no power output.

Tech told me the stator was burnt, quoted me $2300 to fix it. Generator also had motor problems(smoked and used oil). When those additional repairs were added into the mix, the quote quickly went over the price of a new one.
I took another alternative and found a good used replacement in Phoenix, at Arizona RV Salvage.

That one does sound like it was worth replacing. I suspect though, the winding set that fed the voltage regulator (there's two sets) was putting out enough voltage to keep the engine running, even if it wasn't making it out of the generator.

 

[DonTom]

Not necessarily true. When my Onan 5500's stator went out, the genny ran just fine,.

Why didn't the control board shut it down for low AC voltage?

Disregard, I just read the above messages. Seems like a lousy design if the true output AC voltage isn't being detected for the shutdown.

-Don- Reno, NV

 

[UTTransplant]

I would be curious to know what worked for the OP. When this happened to us it was the breaker on the generator.

 

[CharlesinGA]

Just so the OP understands, the circuit breaker on the generator is a difficult to find white toggle. You open the cover of the generator and its to your left down low, below the bottom lip of the opening. cannot remember which way is on.

As noted, do you have an auto transfer switch, or do you merely plug the shore cord into an outlet from the generator. I made a habit of always plugging in any time I stowed the shore cord so the generator would be ready to use.

And yes, if a transfer switch, it could be a loose connection or a burned relay contact.

Charles

 

[Pogrom88]

I'm having the same issue. I have an 88 Itasca sunflyer 27 footer, that I bought from a guy who bought it weeks earlier at an abandoned vehicle auction. The motorhome did not run on its own power, so I drove it home with a 5 gallon gas can behind the passenger seat pumping the gas with an electric fuel pump to the generator. Replacing the mechanical fuel pump did not solve the issue, but dropping the tank and replacing the electric fuel pump in the tank did the trick...and now the motorhome runs fantastic.... BUT...I cannot get the generator to start. The dash is worn down and all the toggle buttons have been rendered unreadable through use...so I found a toggle that has a yellow light in the center. I believe this to be the generator start button, but pushing it, or holding the stop to prime it, does nothing...so I dropped the generator...I checked for spark...none..I sanded the points...tried to start again...and I noticed I had no fuel pump activity to the generator. I jumped the fuel pump...I heard it...no start still...then I realized the pump was making noise...but moving no fluid. I found a faucet fuel pump locally for 200.00 and bought it, rather then the 21.00 Amazon knock off...and the generator started!!!(after I had to bend new fuel line to make this common automotive fuel pump work on my generator).. but my trip inside revealed that I am not getting any power from the generator to the motorhome. I then used a 120 outlet tester and confirmed the generator is making the power...and I flipped every breaker to the power converter...no help. I plugged into shore power, and everything inside the RV works..(except the fridge). I'm trying to figure out how to first...start the generator remotely, or even run without my jumpering the fuel pump...and when it does run, how do I get the power it makes, inside the RV. I'm following every tip I find I find on troubleshooting..but this issue is complex...and standard youtube videos are no help.

I found a wiring diagram to a 1990 sunflyer...and it being only 2 years different...I found that several of the wires described in 1990 are present in the 88...but what I'm not able to locate is "battery disconnect" I'm not sure what it does, and if it will help me...I just know that the unknown number of owners before did not do well with items that no longer function..and I am finding countless cut wires and disconnected spade connectors. I'm hoping to locate someone familiar with this motorhome or generator...and can point me to a direction I have not thought of yet.

 

[ChasA]

Pogrom, welcome to the forum. Do you have an outlet in the compartment where you power cord stows? If so, you plug the power cord into that outlet. The outlet is fed yby the generator. The battery disconnect switch should be near the door so you could reach it while standing outside.

 

[Pogrom88]

Yes...I do have a 240 cord and receptacle. I am not sure the direction of the flow...Ohhhh. you are onto something with that receptacle. I did test that recepticle...and got no power. That box that the "motor home plugs itself into" is actually an extension of a generator recepticle...its a 240 recepticle...but I totally understand...I am hitting it today...hard and heavy...and I assure you...before this day is over...I'll get that generator powering my motorhome.

 

[ChasA]

Is your coach 50 amp,? Does the plug have 3 blades and a round pin? Or does it have 2 blades and a pin? 2 blades and a pin are 120 volts 30 amps.

 

[Pogrom88]

It has 2 blade 1 round pin. I do not know how to describe the configuration of the blades, but I purchased a new receptacle for it, and am going to test the power at the wire, just before the receptacle, to verify the power is coming this far, and is not lost in the wire, and I'm putting in the new receptacle as we speak. I am confident that the receptacle is the issue and I want to thank you ChasA...it was so obvious in my face until you asked about it...it was eluding me. I am not equipt with a battery disconnect switch though...and that saddens me much...nor do I have an hour meter to the genset...but I am confident that today...I will have power.

 

[ChasA]

Okay as I suspected, you have 30 amp 120 volt ac. With your ac voltmeter you should get 120 volts between the 2 slanted slots. It is NOT 240. You should also read 120 between one of the slanted slots and the round hole and zero volts between the other slot and the round hole (ground). Also, the contacts in the slots are quite deep and you may have to use something longer to reach them.

 

[Pogrom88]

I simply bought a new junction box, face plate, and installed the new recepticle. My sniffer remained silent...but once I pulled it out and sniffed the wires...the white had a permanent electricity detection, the BLACK was intermittent. I installed and tested again...nothing
..I cleaned all the contacts...nothing...I pulled the face off and tested the wires...nothing.

Now I know my issue is at the transformer on the generator...but my knowledge of my equipment is limited...as is my time to get this running....I am going to run a crash course on multimeter usage, and I'm going to run through this, cleaning everything up.

I did get it to start from the cab of the motorhome.