Anyone know if there is a fuse for the fuel pump on an Onan 10k QD.

Gen turns over but won’t start. Changed fuel filter and did not fix. Tried to prime but I am not hearing a fuel pump running.

Any thoughts appreciated. If I can’t fix, it will be a warm ride home for the kids.

There is no fuse.
Power for the pump comes from the control board.
12 volts. The brown wire on the pump is the positive side. If you use a separate battery and jumper leads to the pump it should run the pump or use a volt meter and probe the leads to the pump with the rocker switch held down in prime. That’s not a good way to test though because you might see voltage but it’s not sufficient to run the pump. The boards go bad regularly but the pump has to be tested. Pump is pretty inexpensive, board is not !

Thanks. Kind of what I was afraid of.

Why do thinks break right after you buy them?

Control board failures are very common on Onan’s
I did 2 last week.
One a nearly new machine and one about a year old
The fuel pump power loss from the board happens regularly on machines usually with some time on them and generally more often when it’s hot out
On some machines an aftermarket board is available and I’ve used them and they are much more reliable and less troublesome than the Onan
There is no aftermarket available yet for the diesels as far as I know.
I’ve replaced and sold many control boards for loss of fuel pump circuit output on gas and diesel Onan’s

That's why I have always run a lighted switch on my dashboard that supplies fused 12 volt power to the positive side of the pump. I flip the switch and I know the pump is running.

Virtually every diesel Onan will require a control board for this very reason. Each motorhome I've owned has had this failure, and it always happens at the wrong time.

So, Onan/Cummins tech advised the inverter connector is faulty (when he wiggles it the fuel pump will come on) and I need to replace the inverter.

I looked in the Onan parts manual and it doesn't even list an "inverter" as a part in the generator.

Does this make any sense whatsoever?

I haven't seen Rich here since he posted in the vaccine thread. Hope he hasn't abandoned DRR all together.

My old 7K NHM fuel pump quit, wired in a relay and fuse from the battery and picked up power to activate relay from ignition. Worked so good l just left it like that, still running like that for 3 years till l sold trailer, new owner still running it that way.

quote:

Originally posted by Edd Harney:
So, Onan/Cummins tech advised the inverter connector is faulty (when he wiggles it the fuel pump will come on) and I need to replace the inverter.

I looked in the Onan parts manual and it doesn't even list an "inverter" as a part in the generator.

Does this make any sense whatsoever?

He is talking about the control board. One thing to try is disconnect the connector on top of the control board and make sure there isn't any corrosion or loose terminals.

I already posted the easy way to test your machine by powering the fuel pump separately.

There is no fuse, relay or inverter

Whoever you spoke to doesn’t know what their talking about.

Power the pump as I previously described, if it starts and runs that way and not with the normal wire connections you need to replace the control board or do what Don does.

Trust me I know what I’m doing on those machines...and very few people out there do.

I’ve had to tell racer friends who had their motorhomes at Cummins dealers for this type issue to tell the dealer how to do this type test to confirm it. Random shutdowns usually after running for hours.

One place tried to charge $700 diagnostic time after doing the test and I told the owner of the coach to tell them how to do it! With fuel pump externally powered, NO SHUTDOWNS. With pump powered normally, random shutdowns.

quote:

Power the pump as I previously described, if it starts and runs that way and not with the normal wire connections you need to replace the control board or do what Don does.

Thx, Rich. This is what we did. I was able to find a FlightSystems board as a replacement. Onan says there are no Onan boards showing in inventory in North America.

Thx for your help.

There ya go

Flight only recently offered some Diesel boards

I am helping someone fix his 10KW Onan diesel the last few days and his might need a board but there is no direct Flight replacement for his machine I don't believe