Onan 12.5kw not priming and quits after start with code 36

[Ivan K]

This morning our QD 12.5kw HDCAB Onan quit after about 10 minutes. It would always restart for few seconds and quit again. The code tells me that it is likely not getting fuel but what concerns me is that I don't hear the priming sound and the switch is not even flashing when held down. I can imagine that happening with either a plugged filter but even more with a failed lift pump. Now the obvious, I do have 90% full tank, spare filter and tools but the lack of understanding the absence of priming function got me to think whether replacing the filter at a campground even makes sense at this point.  Does anyone know where the usual clicking sound while priming comes from? I think it should be present even with a failed pump if it is a relay? I am researching but maybe someone else already knows first hand what I am looking at? Still looking for a circuit diagram to get an idea. TIA

[Ivan K]

To answer my question, the priming sound is coming from the pump itself. A new pump brought it back. But now I have a much bigger issue, the stator windings burned up few days after AH ignition coil took a dump. Never ending fun keeps me and my toolbox busy in the desert. Luckily,  there is no shortage of cold beer, yet. Just because we have no heat and no cooling does no mean that we give up on this trip...

[Chargerman]

Oh crap Ivan 😳. Sorry to hear. 

[Rikadoo]

Morning Ivan, its a major bummer when the genny fails😡

my Diesel  genny started the quiting while driving down the road, after getting some expert advise about the fuel pump is not working, the tech said i need to check to see if i was getting power TO the fuel pump. So using a test light on the wire to the fuel pump i discovered initially i had no power. I used a jumper wire to give the pump direct 12 volt power an the pump started working an the genny started an ran NP. Once i shut it down then retested for power going to the fuel pump now the circuit was working, reconnected the pump now the genny starts an runs like it always did🤪

doing research on irv2 its known the pcm’s that run the system are known to have a glich an just quit for no reason, at the time there fix was rather than buy a new pcm $$$ there work around was to bypass the circuit to the FP with a switch thats wired to battery power. So then to start the engine ya turn on the FP, warm the glo plugs an start the engine, ya just have to remember once you turn off the genny to then turn off the FP

[Guest Ray Davis]

18 hours ago, Ivan K said:

To answer my question, the priming sound is coming from the pump itself. A new pump brought it back. But now I have a much bigger issue, the stator windings burned up few days after AH ignition coil took a dump. Never ending fun keeps me and my toolbox busy in the desert. Luckily,  there is no shortage of cold beer, yet. Just because we have no heat and no cooling does no mean that we give up on this trip...

Ivan, that's a real bummer sorry to hear it.   How did you determine the stator was burned up,   did you go inside the gen and see them?

[Ivan K]

Sorry about the late reply, gentlemen. We were at Valley Of Fire for last few days with no internet and just moved out to a BLM. 

To Rik's point, after I replaced the pump, it started to prime and I could start the engine for few seconds before shutdown. Once I removed the fuel actuator, the engine would run just fine but no AC was produced. That made it obvious to me that the trouble is either the controller or the windings.  I have tested and tested and all looked good but without a precise ohm meter it is impossible to tell a short from just less than an ohm.

Ray, I had the whole darn thing apart and while checking rotor resistance right at the slip rings, I noticed the burned up stator winding section. Yeah, an expensive repair but I have not sourced the stator yet. If I find one on our way, I'll change it in the field. For now we manage by following the weather and solar works just fine for everything else. And as far as the AH coil, I have one already at home and will have it shipped when we have an address for few days. Fun days ahead 🙂

Thanks for all your comments!

 

[Ivan K]

So my generator saga 'may' be coming to an end, until next time. After couple of months of waiting for Cummins to fulfill my specil order for new 12.5kw stator, I was told the ETA moved an other 240 days with no guarantee that it ever arrives. I gave up on them and sent the heavy (65 lbs) part to Eurton in CA to rewind. Exactly 2 weeks later here it is. Looks like a good job on their part and hope for the damn thing running later today or tomorrow... fingers crossed!

[Rikadoo]

Hey Ivan, man you got a job on your hands there, so just how were you able to find some one to rewind that stator? How was the difference in rewinding vs buying a new one?

When you shipped it did you use a trucking company or ??? Sorry im so full of questions however this appears to be a MAJOR undertaking, did your 12k have a lot of hours on it?

[96 EVO]

Following.

Pretty ambitious job to attempt in an RV park!

I applaud you 🏆!

[Ivan K]

Good news yesterday, the generator is running again as it should. While checking the install before starting, I found a leak at one of the high pressure pumps but a couple of orings fixed that. That took a bit of cursing because of the penta head bolts they use there. They just don't want us to fix it ourselves. 

Here is my post mortem and a couple notes to possibly help someone in the future.

Now I know why the stator burned out. Not because of an overload (it is a 12.5kw unit) but because the cooling air hose was completely plugged by mud dauber nest the size of a big potato. No way to see it until disassembled. All we had running when it happened was one, maybe 2 ACs and a coffee maker, 10 minutes after startup. We were in southern Nevada and it was hot. I will figure out and install a screen at the 4" air inlet below. Also checking for decent airflow out of the windings fan assembly, as in a picture, is a good idea now.

To source a replacement stator was a nightmare. Ordered from Cummins ($1750+T), 2 months later still no ETA, still sourcing a manufacturer, no promisses if ever.. Many hits on Google showing 'in stock', all false advertising since they all are just resellers and have to order from Cummins just like I have. Finally called Eurton Electric in Whittier, CA for rewind. Should have done it long time ago but had my doubts and was prepared to pay for a new one. Got a quote and 2 weeks turnaround. $1250+shipping. Worked out perfectly. From shipping out to receiving at my shop exactly 2 weeks. Very impressed, all wires marked as they should and all correct size terminals and deutsch pins already crimped on. Plug and play. Highly recommend for any sort of winding work. All shipping with UPS ground from and to TX, about $150 total. (used parcelmonkey site for about half off) Expensive experience but finally a good ending. BTW, we are at 3900 hours and all prescribed maintenance is done in house.

And thanks for the above comments. 

[Guest Ray Davis]

Wow Ivan,  another great story.   I am impressed.  Looks like new.  I just wonder how many owners would attempt the job?   Not many I bet.

BTW does the intake hose fit onto the white plastic box?   Looks like a hole about the right size of box lower left.

[Ivan K]

Thank you Ray. You are correct, the hose marked as engine intake goes into the plastic box first, to cool the board, from there to air filter and then engine intake. So there are 3 air entrances at the bottom. Through the radiator to cool the general area, an other to cool the generator windings an then the engine intake. None of them are protected from bug invaders except for the radiator fins serving that purpose.

[96 EVO]

4 hours ago, Ray Davis said:

Wow Ivan,  another great story.   I am impressed.  Looks like new.  I just wonder how many owners would attempt the job?   Not many I bet.

 

I was born in Scotland!

You know I would attempt it 😁!