View Full Version : Northern Lights vs. Cummins/Onan Gensets

Richard O
06-07-2007, 10:24 PM
I am specing equipment on a new-build trawler. The boat, 59' and displacing 126,000 lbs, will be powered by twin John Deere 267 hp diesels.

I need two gensets, one of approximately 20 KW; the other approximately 12 kw. I'm considering Northern Lights vs. Cummins/Onan:

NL 20 kw (M844LW2) & NL 12 kw (M843NW2)


Onan 21.5 QD (MDKBR) & Onan 11.5 QD (MDKBM)

I like the rock-solid reputation of the Northern Lights units but, with sound enclosures, the Onan units are sufficiently smaller to make a difference.

I've heard some rumblings, unconfirmed, that last year Onan had some serious difficulties with the electronic controls on this model series. Not sure if that's true or, if so, whether the issues have been resolved.

Priority one is reliability and servicability. Does anyone have experience with either or both of these model ranges? Any comments, suggestions would be much appreciated.


06-07-2007, 11:05 PM
i had a Northern Lights, I used to deal direct
with Seattle, but no longer can
Northern lights use a mix of OTHER engines, they do not build engines
Cummins do, and I used work for them in Newcastle Au in the early 70,s
I love the Cummins backup, all around the world
IMO I would stick with Cummins
I am not sure what Cummins use(model) on the ratings you need, but I do know that NL use a range of JAP DIESELS an the bloody things always need preheat

10-06-2007, 11:45 PM
I had exactly the same question and issue: the Onan's fit the space I have available and the Cumming reputation is solid.

They also post their owners manuals online. Great, but I found some amazing info:

Since we won't be having access to shore power, we'll have to replace the fuel filters every 2- to 4 weeks, depending on the use.

The fuel 6 injectors (!) , coolant, pressure cap. and thermostats have to be replaced every 3 to 6 months ! That a lot faster than I ever imagined. How do other gen. sets fare in this respect? Ohh, and those fuel injectors, only an authorized Onan dealer is allowed to do it. What about a certified onboard engineer?? Would one lose a warranty?

I find it hard to believe such items have to be replaced between 2 and 4 times a year.

10-07-2007, 01:22 AM
no not injectors

say you have ultra clean tanks with pre cleaner water separators, I would (after warrenty , do the secondary filters every 500hrs
The coolent change every 2 years But I would adhere to the lube oil periods

View Full Version : Northern Lights vs. Cummins/Onan Gensets