Onan genset removal question

[OSCBRADLEY]

Hello,
I have to remove my Onan genset it is a Cummins Onan RV QG 4000 Model 4KYFA26100P. I am taking it out of a 2016 Winnebago Minnie Winne 25B. Why you ask? well I ran it without oil in it last summer and found out the hard way there is no low oil cutoff. I decided in order to save some money I would take it out myself and bring it to a repair shop. It seems the removal is fairly straightforward but then i hit a snag. there are these 3 wires that run from the back of the moho to the genny and once they enter the genny I cannot find then, it seems they are underneath a circuit board that I tried to remove but could not. The wires are the only thing holding back the removal. Before I just them (splice them back together on install) I wanted to check with ya'll in case there was something i was missing here. Thanks!!!

[OSCBRADLEY]

Thats exactly what i was going to do, swap out the engine part (which as i understand it there is an engine part and a generator part). Still waiting on shop to contact me about what kind of damage i caused.....

[j-d]

OUCH!! You are NOT the first to lose a 4KY to low/no oil. You also validated something that comes up often: Searching for Oil Pressure or Oil Level Sensors on any 4KY made in nearly the last 20 years is fruitless - They Ain't Got'Em!
ONAN offers a replacement Engine for these. Not cheap, but cheaper than a new genset. We had a thread YEARS ago (maybe a Decade..) where an OP bought the replacement engine in a crate and swapped it over himself. I might do that, but then again I might not. The same thing could go wrong and blow the new engine. Covered under a warranty if a shop installed it, Not covered if I installed it, even if the work was done perfectly correctly in both cases.

[OSCBRADLEY]

Its out & in the shop, like I said I ran it with no oil so we shall see just how bad the damage will be $$$

[OSCBRADLEY]

Thanks DrewE, removed the circuit breaker and found where the black connects!!! so now im all set to drop it but after measuring I found out that my homemade ramps only gave me about 6 inches of lift. With the floor jack and piece of wood on top of that plus the generator height I need bigger ramps. So unfortunately removal will have to wait for a week or two. Thanks so much for everyones help!!!

[DrewE]

The black wire connects to the AC circuit breaker on the generator control panel (unless they've changed things, which I rather doubt). It kind of snakes around the bottom pan of the generator to get there.

[OSCBRADLEY]

I wish I had a junction box, it would have made this so much easier but the wires running into my generator are enclosed in heavy rubber conduit that runs from the generator which sits just behind the driver all the way to the rear of the motorhome where goes inside the RV, no junction box unfortunately.

[cgmartine]

I Have a K series generator that I removed just a couple of months ago. I used a motorcycle jack, which made it quite easy. As for the wires, I found out that they should be taken off at the junction box. There is no other way, since they are part of a wire loom that goes to another part of the generator, so don't pull on that end of the wires too hard. Make sure you also remove the muffler before you lower it, otherwise you will crush it. The mechanic will probably thank you, since it is sometimes a tedious job. He can also bench test the generator easier once it is out and can supply it with gas from a gas can. In fact, my son and I lifted the generator and placed it in the truck of our car and took it home to my garage. I had my generator running in my garage. It is not as bulky or heavy as it seems.

[OSCBRADLEY]

DrewE,
That's exactly what I did, I made some ramps and drove backwards on them so they wouldn't be in my way. I have a floor jack for the final removal if I decide to take it out. After measuring I should have a few inches to spare (I hope).

[OSCBRADLEY]

So I found the 2 screws that were holding in the circuit board, they were right in front of me the entire time but I thought they were for removing the outer case of the genset....apparently not. So I removed the solenoid and circuit board (thanks to everyone's help!!) found out where to remove the green and white wire (easy) but the black wire runs into the other side of the generator, looks like it might connect to the start switch. I'm SO CLOSE (i am fine with cutting the black wire and splicing it later since the splice will be inside the generator and not really exposed to the elements. HOWEVER, now i'm thinking is this really the best way to get this serviced? or would it be better to leave it in the RV and have a service guy look at it? I would hate to take it out and have the tech say "gee, I wish you had left it in the motorhome"......Like I said earlier the reason I need to remove it is because I ran it without oil so i am sure it will need some extensive work.

[DrewE]

OSCBRADLEY wrote:
OK, I took a look at the solenoid & Circuit board. I can see how the solenoid comes out but the circuit board......not so much

There are screws, though they may be in dark corners. I don't recall any real difficulty in sussing out how to detach the components. On mine, at least, I think there were two circuit board modules, one on top of the other, and the top one had to be removed first before the bottom one could be extracted.

One hint: when you get to the point of actually lowering the generator, measure the clearance between the bottom of the skirt and the ground on the motorhome and check whether you'll need to drive that side up on ramps or something to get the generator out from underneath (which presumably will involve a dolly or floor jack or something underneath with wheels). The generator weighs something like 150-175 pounds.

[Kpackpackkelley]

I’ve seen the junction box a long ways from the genset, you could put another junction box closer if you like. When you find the junction box and pull the wires through pull a wire or string through the conduit for when you pull your genset wires back in.

[enblethen]

Isn't there a small box mounted to the side of the genset compartment where the flex conduit ends?

[OSCBRADLEY]

OK, I took a look at the solenoid & Circuit board. I can see how the solenoid comes out but the circuit board......not so much

[randy328]

DrewE wrote:
On my Onan of that model, albeit quite a few years older, the neutral and ground connect to a little star shaped thingy inside the generator opposite the 12V ground wire connection (that, indeed, the 12V ground wire is bolted up to). The hot wire snakes across the bottom and connects to the AC circuit breaker. To get to them, it was necessary to remove the starter solenoid and control circuit modules from the left side and to at least partly disassemble the control panel unit on the right side. A torx screwdriver of the appropriate size was about the only tool required, but it did take a bit of labor and poking around in slightly tight corners.

I removed mine a few months ago, KY spec, and you still have to do exactly what DrewE said. Solenoid, board, and part of the switch unit.