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Chev64 · 06-13-2016, 07:04 PM

Replaced Fuse F2 gennie still won't start. Any ideas?

Skip426 · 06-13-2016, 07:17 PM

Do you have more than a 1/3 tank of fuel in the tank .
Gen sets are set up so they can't run the tank dry and strand you in the boonies.

dabrooks · 06-13-2016, 07:32 PM

Will it turn over and not start or is it not turning over.

Skip426 · 06-13-2016, 09:33 PM

Quote:

Originally Posted by dabrooks

Will it turn over and not start or is it not turning over.

Boy am I dumb , that should have been my first question.

Chev64 · 06-14-2016, 11:07 AM

Have 1/2 tank of gas, gennie turns over fine. No fuel, can't hear fuel pump. Fuses are good. Think I will replace relay K4 next. After that, I have no idea!
Very fustrating!!

twocoots · 06-14-2016, 11:27 AM

Open the gen cover and use the start button on the gen. If you press down on the start button you should near the fuel pump. If the fuses are good and you don't hear the fuel pump then the fuel pump is probably bad. You can get a pump at NAPA and replace it yourself. Easy replacement.

okcnewbie · 06-14-2016, 11:49 AM

Follow the manual troubleshooting tree and you won't have to guess. It looks something like this.

Chev64 · 06-14-2016, 07:39 PM

Thanks for all the help everyone! Back to troubleshooting tomorrow!

B Dubya · 06-14-2016, 07:43 PM

I don't see anywhere that you did the onboard diagnostic. If you do, I'll give 2-1 it reads a code 36. In fact, I think that's the only code these things throw!

pchuckie · 06-14-2016, 07:53 PM

Providing the fuel pump is the problem, save yourself a ton of headaches and get the proper Onan pump. There are a lot of fuel pumps that look the same and all have different operating pressures.
Depending on the vintage of your generator and the model, most newer Onan gen sets have a prime feature if you press and hold the stop button.

Chev64 · 06-15-2016, 11:51 AM

Ok, haven't had time for more troubleshooting today. As far as on-board diagnostics, I don't think my generator supports that. There are no lights on the generator and the switch doesn't light up either.
When I depress the start/stop button, it turns over fine but no fuel pump noise. Think I will try a separate in-line pump and see if that works.
This 1997 ONAN generator doesn't appear to have a prime feature!

pchuckie · 06-15-2016, 12:38 PM

Use a volt meter and see if the control is supplying 12 volts to the pump while your cranking it.

Chev64 · 06-20-2016, 02:56 PM

Replaced the K4 fuel pump relay, no difference. Checked for 12vdc at the pump while cranking. Got 12vdc, still no fuel. Found out there is a fuel pump solenoid E4, however can't get to it to check it out. Have a new fuel pump on order should be here Wednesday. Does anyone know if the fuel pump solenoid can be bypassed. Can't seem to find one.

pchuckie · 06-20-2016, 05:53 PM

Just disconnect the wire to the pump and run a wire from B+ to the wire on the pump. It should pump fuel if the fuel pump is serviceable.

You should have narrowed that down when you checked for b+ at the pump while cranking. However I can think of two possibilities were 12 volts wold be present at the pump and a serviceabe pump would work.
1. The pump housing is not grounded, pretty sure your pump is a single wire pump.
2. You have a loose or dirty connection somewhere that allows 12 volts to appear present but drops to 0 once current flows through the pump. Not very likely since you measured 12 volts at the pump and I'm not aware of any internal thermal protection on Onan fuel pumps that might open and close causing you to read 12 volts bit it not be able to make the pump run.