Northern Lights generator with J Deere model 6068HF275 4000 hour service?

I don't know what service is required. But, for the work that is mentioned, it's basically a complete upper end overhaul and the price seems fair for the work quoted.

I think you are being taken for a ride. As Capt. J stated that is a complete top end over haul. I am not sure of the model, but I previously went almost 20k hours on a NL 65KW before a complete overhaul.
If it is a larger unit this should not be considered until at least 10k hours. Now if it is a smaller high rpm unit this could be different. I would check with NL directly, but in my experience they do not have a time frame to do this work in their maintenance schedule.

I also think you are being taken for a ride.

Are you looking at this as a time based review or is the engine exhibiting behaviour that leads you to believe a fairly major rebuild is required.

I notice it says replace Piston Rings, this is a lot more involved than doing a top end overhaul. The crank bearings will need to be inspected and replaced as required. You will need a sump gasket and may also need an oil pump.

I found a manual that calls for a top tune at 2000 Hrs so I would be very surprised if it need an overhaul at 4000 hours.

If the engine is running ok, remove the injectors and borescope it. If its throwing black on the water change the injectors and fuel filters , clean and inspect the turbo, change the air filter and see what happens.

If you are running it at light load longterm the slobber problem is well known.

37 mph southerlies right now

I would ask to see the Northern Lights maintenance schedule document that indicates this need. This is just like auto dealers who say you need $1000 service at a mileage the manufacturer says you need nothing. I pulled up a couple of different Northern Lights manuals and none of them indicate the need for anything at 4000 hours. I then pulled up a couple of Deere documents. I find nothing of that nature. Then I think of some basic logic.

1. Engine operating fine.
2. Oil Analysis indicates no problem. (hopefully you have one).

Then step 3. does not logically say to rebuild the engine.

Again, I'd ask to see something in writing from the manufacturer or be given some solid evidence such work was needed. Give Northern Lights a call and ask what they have to say about that. We are diligent about all manufacturer suggested maintenance but not about some contrived schedule invented by a dealer to build profits.

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