Onan RV Generators

[TFucili]

In my toy hauler shopping(separate thread)naturally generators are part of the equation. I have considered not getting an on-board and getting a couple Honda inverters, but still lean towards on-board power. Onan, as usual, is the predominant brand, but the more I dig the more I find Cummins/Onan is about label engineering.
First an aside, I used to be in the equipment business, and Deere used a lot of Onans at that time, mostly B series and the Performers, which were updated Bs. Also serviced other equipment that had CCK, etc. When my Homelite rep went to Onan, I actually became an Onan dealer. Even at that time their contractor generators were off-shore gens, and I owned a 6KW with a Kubota OHV gas motor. I also know they farmed out production of the Performers to Linaman(?) at some point. Back to today, I assumed the RV generators were still Onan, but they appear to be Fuji-Robin/Subaru engines. The EH65V twin is, and the EO95 appears to be, but I have not found as much info on that particular one.

Does anybody have first-hand experience with these units? I am not afraid of Robin engines, as I was a dealer/service center for them too, HOWEVER, Subaru has completely dumped the small engine business somewhat recently, so who is actually manufacturing them now? I doubt Cummins/Onan took it in-house. Lowest Chinese bidder? They get big $$$, so I hope they haven't gone down hill like so many other things.

 

[Cummins12V98]

I have the 6500 Commercial 240V CUMMINS Gen. No idea who makes the engine. It works well is all I can say.

 

[TFucili]

Thanks for the info. Best I can tell is that has the same v-twin EH65 as the 5500, but turning 2800 RPM instead of 2400. Is normal maintenance stuff pretty easy to access?

 

[Cummins12V98]

Thanks for the info. Best I can tell is that has the same v-twin EH65 as the 5500, but turning 2800 RPM instead of 2400. Is normal maintenance stuff pretty easy to access?

Yes doing an oil change was very easy.

 

[Killer223]

my onan 5500 is from 03, and it's been an amazing generator, never an issue, i change the oil once a year.

 

[p-Bar]

Have same type unit in my 5er I installed runs on propane . Easy to maintain. Hotwired the transfer switch to power the house when they killed the power for the fire we had here last December.

 

[Shadrach]

Onan is complicated. In the bigger units they use all brands of engines. including Cummins. RV diesel used Lister and now Kubota. Older RV, BGE and CCK used Onans own engines and so did the Performer Series of industrial engines. Later Linamar, a Canadian part manufacturing company, built them. Robin/Subaru built the red Onan portable genset but they haven't been built for years now. I have use a 3200 one and it worked great, but with any portable you have to go out to start and stop it and it can get stolen and can't get wet.

If buying a new RV then I highly recommend buying it with an Onan already built in as this is the most economical way to go, other than buying a "cheap" non name genset. This way you just push the start button and away you go. To add a built in Onan afterwards is more expensive. If it is a Toy Hauler it can be equipped with a gasoline 5.5 kw unit as it will have a gas tank at the back. If it's not a toy hauler then I personally find LP more convenient as you don't need to carry gas but it make the genset more expensive.

 

[Cummins12V98]

To be clear Onan name is going away as they are owned by CUMMINS.

 

[mpaulson]

One thing for the OP to consider and as a question to others.
My toyhauler came with an Onan 4000 built in and I hated it so much that it is now sitting in my shed. The thing was loud and it vibrated the trailer to the point that the drinks in a glass had rings rippling in them.
So I went back to using my command startable Honda3000 mounted on the truck for a silent use.
I was ashamed to use the Onan in campgrounds during generator hours due to how loud it was as well.
Do the rest of you get the in trailer vibrations?
It’s too bad that the space it was in is only about 2” too low to get the Honda into it.

 

[Cummins12V98]

I have ZERO issues with mine.

 

[Tuesdak]

I would recommend finding an older 2 cylinder 1800 RPM Onan. They go for around $500 a pop for the 4KW versions used. Night and day the sound of 1800 RPM vs. the 3600 RPM screamers.

The second something expensive dies on the LP 3600w Onan screamer on my RV I have an old 1989 2 cyl Onan 1800 RPM unit ready to drop in. It will be awhile I expect. Bad of the older ones is the regulators go pop from not running. (Oxidized high resistance slip rings from not running and said regulators are expensive). As well as 1989 having "points".

Toy haulers usually have a gas pump for the toys on board so gasoline is common. Regardless Gasoline goes bad quick and exhaust smells bad vs. propane.

I do not have a vibration with my Onan. Louder than some others, yes. However it can and does power the AC going down the road, is pushbutton from the inside while not dressed to get Coffee going, isn't likely to easily walk away, and doesn't require setup or teardown at camp. Well unless I run the Gen-turi exhaust extension.

Even the newer garbage Champion portable RV gensets are fairly quiet. Regardless as long as it meets the Forest Service noise limits and there are generator hours...

 

[CBari]

I have one of the Onan/Cummins QD units the 6000kw it is unreal how quite it is and how little fuel it uses. It is an inverter also. The diesel engine is the same for the 6k-8k units it is a kubota engine. The 6-8k units all use the same internals except for circuit breakers and governors. I have had the gas units by both generac and onan and I will never do that again. There are a fair amount of diesel pull offs if you look for them anything with under 2k hours will be like new. I found mine it had a 197 hours on it, I gave $4000 for it. My fuel tank is 20 gals and it ran it full load to roof ACs plus everything else for 5 days and still had 1/4 of a tank.

 

[KATOOM]

I have a 5500 Marquis Gold in my '05 trailer. Works great and is pretty quiet for such a big unit. I understand the newer ones now have variable speed on demand, but I cant confirm that for sure.

The BIGGEST issue I see with these generators is people never look at them or maintain them but yet expect them to work on the once a year family camping trip. ANY combustion engine that uses gasoline will absolutely require starting it every few months for about 15 minutes just to keep fuel moving through it otherwise it will clog up the tiny ports in the fuel system and cause problems. And...run fuel conditioner too. Today's ethanol fuels are horrible...!

 

[AMink]

My toy hauler has a QG5500 EVAP. I believe it is an update, maybe in name only, of the Marquis series. It works well, is pretty quiet, and easy to service. I still carry my Honda 2000 if I just need to charge the batteries. Also, if you trailer batteries get too low you can't start the onboard gen. My buddy found that out the hard way! I really like the ease of the inside pushbutton start for microwave or a/c use.

 

[Northfork]

2014 5th wheel here with Onan 4000 EVAP.
At about 120 hours the fuel pump died. I looked at the thing and it's location and decided to put a small electric aftermarket pump in place of the stock one. Found one that was internally regulated at 4PSI.
Unit starts much quicker now. I regularly use Lucas Ethanol fuel treatment in the gas tank and have had no issues. We normally use it at 5k ft. elevation, and last winter in Death Valley I had to reset the altitude adjustment on it to make it happy. No surprise there.
A few days later the fuel pump died and I dug out the Honda EU2000 we have had for years and cranked it up...and had to tickle the choke a bit to get it to run correctly as well.
Apparently below sea level operation requires some adjustment LOL.
I use the little Honda a lot, while we almost exclusively boondock and really don't have too many people around to worry about annoying, but the Honda burns less fuel and will run the TV and Satellite box just fine and even the microwave now and then.

 

[KATOOM]

My toy hauler has a QG5500 EVAP. I believe it is an update, maybe in name only, of the Marquis series. It works well, is pretty quiet, and easy to service. I still carry my Honda 2000 if I just need to charge the batteries. Also, if you trailer batteries get too low you can't start the onboard gen. My buddy found that out the hard way! I really like the ease of the inside pushbutton start for microwave or a/c use.

I found this out the hard way too. Running the energy hog heater all night during cold battery weather camping, in the morning the batteries were too weak to start the generator. So I installed a dedicated 12 volt battery just for starting the generator. Generator starter is no longer connected to house batteries. And because the generator cant charge two 6 volts and one 12 volt battery, I run a battery tender/charger to the generator start battery which keeps that battery charged when the gen is running or on shore power.

 

[Dieselnut59]

I have one of the Onan/Cummins QD units the 6000kw it is unreal how quite it is and how little fuel it uses. It is an inverter also. The diesel engine is the same for the 6k-8k units it is a kubota engine. The 6-8k units all use the same internals except for circuit breakers and governors. I have had the gas units by both generac and onan and I will never do that again. There are a fair amount of diesel pull offs if you look for them anything with under 2k hours will be like new. I found mine it had a 197 hours on it, I gave $4000 for it. My fuel tank is 20 gals and it ran it full load to roof ACs plus everything else for 5 days and still had 1/4 of a tank.

That is what I want to do when I get my Grand Design toy hauler. I cant believe they will not give a diesel option on their units. I will get it with "generator prep" but no generator, then add my own generator. My "toys" run off diesel, so the tanks will only be filled with diesel.

 

[KATOOM]

We dont camp enough to justify dumping anymore money on our toy hauler... But if I ever felt the need to do something about power consumption, I think it would be cheaper and easier to invest in a decent solar system so that I could spread out my options.

 

[Shadrach]

To be clear Onan name is going away as they are owned by CUMMINS.

In 1986, Cummins began acquisition of Onan and completed it in 1992. Since then, Onan has evolved into Cummins Power Generation (now Cummins Power Systems), a wholly invested division of Cummins. The name is still used today on generators.