10CW Onan amp output


In this case the set is 10 kW, but the generator is 12-1/2 KVA, being rated at 80% power factor. 2/3 of that gives 8-1/3 kW. But we are also talking about an 88 ci CW. It’s my understanding that those in particular are thirsty to begin with. I’d bet shaving the heads a bit would help. :brows:



Len, I completely understand with your fuel consumption numbers, that's one of the reasons why I also own a diesel set, among all my others, but you're forgetting that the fuel consumption of the 10 CW is part of its novelty :D :bonk: :brows:

Jim McIntyre

Well this is a forum on operating vintage Onan generators, so I'm not going to discourage use or restoration of this old gem. If fuel consumption really matters, get a Honda inverter set :).

I passed up one of these at a local auction a few years ago and kinda wish I hadn't.

I've not seen the consumption rating for the 10CW - it's not in the owner's manual as far as I see. I suppose it might scale linearly from the CCK set, and based on the 88 cu in/ 50 cu in ratio, end up being about 1.7 GPH on gasoline. That would get annoying after a few days for sure, if you were using gasoline. If converted to NG, not so much...

len k

My heavy emphasis on gasoline consumption is because of practical maters, running continuous for 1 week . No nat gas here, I have to carry it all. And it's a LOT.

Few years ago neighborhood behind me was out for over 1 week straight, after wide spread ice storm. I had power. Scared me, I need electricity to run my oil furnace or I freeze.

After I picked up my 7NHM I learned it's fuel consumption, was shocked at how much I'ld burn in a week , continuous run. Very glad I didn't get a 15kw JC , I could go with smaller gen even.

It's a gasoline cost AND transport/storage problem. 1 week takes bit over 55 gal barrel at no-load, with load more likely several barelles, HEAVY and lot of work to move for an older guy.

That's why I've talked about taping our Chevy's 22 gal gas tanks and using it to transport gas from gas station, a couple miles away. And 12V pump it out to large gen tank so don't have to carry it.

Have city water, oil furnace makes hot water. I dry clothes on line outside, even in winter.

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New member
I'm not concerned with the fuel on this 10CW. I work for Cummins so I got a really good deal on a new Onan and I have a Yamaha inverter, also power is very reliable here. The 10CW is just a cool looking machine and I'm excited to get it cleaned up and running good.

Anyone got any feedback on that question I asked earlier about load banking with a welder or did everyone just think, wow this guy is crazy.


Active member
Anyone got any feedback on that question I asked earlier about load banking with a welder or did everyone just think, wow this guy is crazy.
Yeah, don’t do it. You want a resistive load for a load bank so that you just load kw without weird power factor or harmonic current issues. Welders are nasty loads for generators, especially if you’re running a welder to load a generator up to near full capacity. Screwy current demands might cause screwy issues with a generator and you end up chasing phantom problems.

Best to stick with “real” load banks, or the usual ‘Stak method of using heaters, hair dryers, and big incandescent lights — all of which are resistive devices that make good test loads for generators.