Gen starts but shuts off - 1999 Minnie WF 331C

[Tekman2000]

Hello All,

I have a 1999 Winnebago Minnie WF 331C and it has a Cummins Onan
Model # FKY FA26100H generator that has 316 hours on it. (Please see picture)

It starts and runs briefly with starting fluid spray but shuts right off.

I’m thinking fuel supply issue??? But I would really appreciate your expert inputs. Maybe someone knows of a particular issue with this model???

I just purchased this motorhome a couple months ago. And I have been waiting for the rain to slow down so I can do some diags when I am not at work.

I have been reading a lot about this generator and researching troubleshooting docs and videos.

I am aware of oil level sensitivities…. Current oil level is right at “ADD” on dipstick when cap is screwed in.

I am aware of vehicle gasoline fuel level sensitivities… Motorhome fuel tank is FULL.

Thanks in advance (Smile)

[Eagle5]

Hi Tekman2000,
As far as the oil level is concerned, you really cannot overfill those generators, but if it is at <Add> with the oil fill cap fully-screwed into place, then you are just about to get too low.
Another idiosyncrasy of those generators is when starting them, you really need to hold the button in the <Stop> position for about 10 seconds which primes the carburetor, and then press and hold <Start> until it really starts. In other words, the generators will "catch" and sound like they are getting some firing, but when you let go of the <Start> button, the generator flames-out. Just hold <Start> down until it really starts.
If the above doesn't work, then you need to clean the carburetor.
Eagle5

[Tekman2000]

Hello Eagle5,

Thank you so much for your reply, I REALLY appreciate your assistance with this issue.

I had a chance to stop by my Winnebago for a few minutes until they called me back to work.

Using your advice the generator runs as long as I keep pressing the start toggle. And when I pulled the fuel line off the carburetor fuel IS being pumped but ONLY with the toggle held down in the start position.

I actually ran the generator long enough for it to warm up.

I’m going to look for the electrical schematics because it IS actually a fuel issue, but more specifically it is an electrical issue which causes an open circuit at the fuel pump unless the rocker switch is in the “start” position.

[creativepart]

Sounds like you are on the right track - but as Eagle5 said, oil level is critical.

There is a "cutoff" built into the oil level sensor that cuts off fuel when the oil level is below a set point.

You might be right and there is an electrical (or even switch) issue but the first thing to try is to fill the oil level to halfway between Add and Full.

These can be so sensitive on the 4K gensets that turning hard can kill the generator. All the Onans above 4K have oil filters which help hold quite a bit of extra oil. But the 4K doesn't have an oil filter and the oil in the reservoir is all there is.

[Morich]

I am slow to get involved with discussion of generators as I don't feel qualified. But I did get into a long drawn out failure of one that was finally tracked to a board on the generator!
Whay you are finding when it fails after warming can be easily explained if a board on the genset gets hot and some trace goes open! If it is the solder trace on the board which controls the fuel, the fuel gets cut off!
So just some guessing without looking at that board seems to say that when you are pushing that putton, you are using a different path than when the engine is running without the button pushed. Not an unusal setup but the trick is to find a good enough drawing for the specific genset you have and going deep enough to get down to the way the board itself works.
Possible to do that but I did not do the finding and have no idea how or where he was able to get it. As I remember the discussion (shaky!) it was that he could start the genset from the engine but none of the inside switches. We started at the wrong end as we knew where the inside switches were and he chased it all the way to the board on the engine itself before finding he needs to strap around a bad trace on the board!
Quite a chase on an RV that had switches at possibly three different points but he hung in and finally found the problem.

The fix was easy, finding it was terrible.

So the big problem may be if you can get a drawing for the specific model generator you have and is it complete enough for us to sort where holding the button gives a different route to hold the fuel pump.
Can you see the board and get to it?

No warrenty on my guesses but that might be a point to look over.
When all else fails we have to do SOMETHING!

[Tekman2000]

Hello all,

I really appreciate everyone’s input and help. (Smile)

Unfortunately, my Onan generator model KY series H does NOT have a diagnostics code light as at least one person has pointed out. You guys ARE able to see the images of my genset, right? (Smile)

Also, they have pointed out that there is NO oil level sensor either. But just to be on the safe side… I will carefully increase the oil level to just below the “FULL” mark with the dipstick screwed in. This one does NOT make sense and I hope it is wrong??

Anyway, I found the COMPLETE FULL original manuals for my Motorhome. They are at least on the level of “Chilton” automotive repair manuals if not as good as “Mitchel” shop manuals; VERY detailed. They were in one of the cabinets and I hope I mentioned that I just bought this Winnebago a couple months ago.

We are having something called an “Atmospheric weather river event” (aka: constant rain) here in the Pacific Northwest and with my health AND my three part time jobs I will continue to diagnose this generator issue as soon as possible.

So next, what I am going to do is:
A: Carefully fill the generator oil level to just below full.
B: Using a long high quality extension cord and my digital VOM (Volt Ohm Meter) I will start the generator and see if there is at least 80 to 90 volts AC (alternating current). This is the minimum voltage that must been seen so it goes into “run” mode. Even better if my VOM shows 115-120 volts AC.

I just wanted to give everyone a heads up and let you all know I am still working on this.

When we get to the bottom of this I will treat everyone out to the beverage of their choice (smile)

(PS. To answer a couple of questions: My genset has 316 hours on it as I mentioned in my OP. (Smile). Also, thank you VERY much for pointing out how corroded the main 12 volt battery cables are at the solenoid…. I DO know the importance of having clean and tight battery cables. I will be splicing in and soldering a good length of brand new cable once I verify that the cost of getting this Gen to work properly is less then say $300. Because I can buy a brand new gas generator (Third party, NOT Cummins) for about $350. And although my battery cables at the Gen solenoid are terrible it cranks just fine.)

Thanks in advance, and I will keep everyone informed.

[Morich]

Overall, most of us are in the "part time DIY group" and that means most of us have learned we don't work on things 8 hours straight! So lags between things for weather, parties, ball games, or trips is kind of the norm here!
A fair number of us don't work at all any more, so if it takes time to get back to it, we can live with that!

I kind of like the electrical side of things, so do you have an exact model number for me to do an online search for info on how that start switch makes it run and then it fails after you let go of the switch? That seems to say there should be a second path taking over once the engine is up to speed and possibly that second path is the failure??

Just promise to buy me that coffee when you see me and I'll work all day!
But be aware I do lie at times when it is needed!

[Ray,IN]

Most small engines with a screw-in dipstick measure the oil level when the dipstick is not screwed-in, it is just pushed in until it hits the threads. The threads are simply for sealing the opening.
Why the reluctance to add enough oil to the full-line?

[Eagle5]

Originally Posted by Ray,IN

Most small engines with a screw-in dipstick measure the oil level when the dipstick is not screwed-in, it is just pushed in until it hits the threads. The threads are simply for sealing the opening.
Why the reluctance to add enough oil to the full-line?

Yes, this is how I check the level on my Generator, and I am glad you are pointing this out. With the oil level just about to spill-out the opening, that reads full on mine, so you really cannot overfill it.
Thanks, Eagle5

[Morich]

Jusat as info and not to tweak your nose or anything, I thought this might be interesting, even if it is way , way past prime!!
Just something that popped up as search for your model info:
https://www.k-bid.com/auction/20547/item/176
Maybe a used salvage can be considered?

But prices will likely have changed in near six years!

[Tekman2000]

Hey all,

I wanted to give everyone an update on my generator issue.

I haven’t been able to make any progress on it lately because of work obligations and lack of extra funds but my son in law has a friend that is manager at one of the main trailer and RV dealerships here in Portland Oregon.

I spoke with him the other day and he said he sees this all the time on Motorhomes that sit for a long time. He told me it is a dirty or corroded STATOR…. AND that he has a special tool for cleaning the stator without taking the generator out of the vehicle.

Is this possible on a 2000 Winnebago Minnie with a Cummins Onan Model # 4KYFA26100H generator? Has anyone heard of this? He said if his tool works great. If not, then the stator needs to be replaced which requires pulling the generator.

[wyocamper]

As others have stated, I would just add oil first and see if it helps. I've never looked at the dipstick, if the oil is right up to the fill hole then it's full. If it's not about to run out then add some more. If the level is at the Add mark with the dipstick fully screwed in then it's essentially empty.

[Tekman2000]

Hello WYOCAMPER,
Thank you for your suggestion. (Smile)
A LOT of people have suggested that it is the oil level. I REALLY wish it was that simple, but unfortunately it is NOT.

[Tekman2000]

Hello all,

I finally had a chance to run a couple of tests.

1) My generator runs GREAT as long as I keep pressing the “start” switch at BOTH the generator and inside the carriage. YES I understand that pressing the “START” switch keeps the starter engaged (that’s for those that want to warn me about possibly burning out the starter).
2) As soon as I let go of “Start” it just shuts off as if I am pressing “Stop”.

It turns out there is absolutely NO voltage output from the generator side of this Onan generator. The ENGINE side is working fine.

If I were still working as an ASE certified automotive repair technician I would take the generator out and rebuild it. But unfortunately I had to have both my hips replaced due to osteoarthritis and I just can’t get around like I used to.

[Eagle5]

Hi Tekman2000,
These guys are in your area, and are highly rated with 4.7 stars & 140 reviews:
http://www.atyourdoorrvservice.com/
Please let us know what the RV Technician finds out, OK?
Thanks, Eagle5