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Author Topic: Onan 4000  (Read 340 times)

Racer403

  • Posts: 4
Onan 4000
« on: January 19, 2018, 02:59:07 PM »
I just replaced carb with a new one, plenty of fuel pressure and it will fire with starting fluid but not run. I jumped the fuel shut off wire to the positive side of solenoid, sounds like the carb is being primed. Any suggestions

Bill

PJ Stough

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  • Posts: 1660
Re: Onan 4000
« Reply #1 on: January 19, 2018, 03:49:55 PM »
Did you take the fuel bowl off to see if it has fuel in it?  If not perhaps the float is set too high, or the needle valve is stuck. Where did you measure the fuel pressure?
PJ Stough   Iowa
2005 Winnebago Voyage 38J

Racer403

  • Posts: 4
Re: Onan 4000
« Reply #2 on: January 19, 2018, 03:53:04 PM »
I took off the fuel line at carb and the hit start into a bucket

PJ Stough

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  • Posts: 1660
Re: Onan 4000
« Reply #3 on: January 19, 2018, 04:00:22 PM »
My next step would be to take the fuel bowl off and try to start it to see if fuel is actually coming into the fuel bowl.  If not, then the needle valve is not opening. Perhaps, to keep the float from bouncing up and down during shipping, there is something holding up the float that has to be removed before the float will work. Otherwise, I would say the needle valve is stuck, or the float is way out of adjustment.
PJ Stough   Iowa
2005 Winnebago Voyage 38J

Racer403

  • Posts: 4
Re: Onan 4000
« Reply #4 on: January 19, 2018, 05:50:42 PM »
I pulled carb back off and took the bowl off to check for obstruction.  There is not an adjustment for the float. Aggravation has stepped in, going to check to make sure solenoid is working.

grashley

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  • Posts: 5043
  • Western KY for now.
Re: Onan 4000
« Reply #5 on: January 19, 2018, 06:34:20 PM »
First, do not touch it for 3 days and allow the stress to go away.

I assume this is not a new genny.  Is it possible the fuel line is sucking air in through cracks in the hose when fuel is sucked through the lines?  Would your fuel line test  at the carb already have eliminated this problem?
Preacher Gordon, DW Debbie
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It's not a dumb question if you do not know the answer.

PJ Stough

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  • Posts: 1660
Re: Onan 4000
« Reply #6 on: January 19, 2018, 06:39:00 PM »
I pulled carb back off and took the bowl off to check for obstruction.  There is not an adjustment for the float. Aggravation has stepped in, going to check to make sure solenoid is working.

Was there fuel in the bowl?  If you have fuel pressure where the gas goes into the carb, but no fuel in the bowl, it would have to be that the needle valve is not opening.  With the bowl off of the carb, move the float up and down to see if the needle valve opens and closes.
PJ Stough   Iowa
2005 Winnebago Voyage 38J

Racer403

  • Posts: 4
Re: Onan 4000
« Reply #7 on: January 19, 2018, 08:27:41 PM »
The problem was the fuel solenoid, looks like the dealer switched it out with a older one. It was rusty but I will deal with them later. The gen started but then shut down with code 36. I just ordered new air and fuel filters that it needs badly. Just got this coach and it needs some TLC. Thanks for the help.

Heli_av8tor

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  • Posts: 472
Re: Onan 4000
« Reply #8 on: January 19, 2018, 08:54:03 PM »
Glad you solved the problem.
Believe me, I know how good it feels to solve a genny problem. LOL
Tom & Theresa
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