How To Onan generator problem

[Ivy]

New to this forum. Wandering if anybody got aa idea with my generator trouble. I have a 2020 onan 7000 generator in my tiffin open road. Generator runs find sitting still. Will run for hrs no problem. When I crank up and start down road. Gen goes down after around 15 min and won’t run . Code is 36 which is fuel problem. Changed fuel filter and fuel pump twice. Also tried different oil levels. No luck. Took back to dealer, they had no one to work on it. Thinking about installing auxillary fuel pump. Any ideas would be appreciated.

 

[redbaron]

Has this ever worked properly?

My guess is that the fuel line going into the main tank is not deep enough, and therefore the sloshing movement is causing it to cavitate and run out of fuel.

 

[Ivy]

Has this ever worked properly?

My guess is that the fuel line going into the main tank is not deep enough, and therefore the sloshing movement is causing it to cavitate and run out of fuel.

It never has worked properly. It still shuts down with a full tank of gas. It will run on less than half a tank sitting still.
Thanks

 

[redbaron]

It never has worked properly. It still shuts down with a full tank of gas. It will run on less than half a tank sitting still.
Thanks

You need to fix the fuel line going into the tank. Either there is a kink, or it is too short.

 

[latech]

While driving , the fuel evaporative system valve is closed and the engine module opens a valve(purge valve) that pulls a vacuum on the fuel tank. Then the engine control module monitors the tank pressure sensor to see if it holds vacuum. If it does not codes are set.
While this is going on , the generator starves because the generator pump cnt pull against the vacuum imposed by the evaporative emission system.
You need to vent the tank, without conflict with the engine evaporative system on the coach engine.
Too bad you dont have a dual fuel generator, you could just run it on propane while driving

 

[latech]

You could loosen the gas cap and drive to see if that clears up the problem.The engine will likely set a P0455 evap code, but that is easily cleared. If the problem disappers, then you are on the right track

 

[Ivy]

I have already tried removing gas cap and driving coach. Still shuts down.

 

[Engleman]

New to this forum. Wandering if anybody got aa idea with my generator trouble. I have a 2020 onan 7000 generator in my tiffin open road. Generator runs find sitting still. Will run for hrs no problem. When I crank up and start down road. Gen goes down after around 15 min and won’t run . Code is 36 which is fuel problem. Changed fuel filter and fuel pump twice. Also tried different oil levels. No luck. Took back to dealer, they had no one to work on it. Thinking about installing auxillary fuel pump. Any ideas would be appreciated.

Cummins shop.

 

[Ivy]

Cummins shop.

Been to shop twice. Can’t find a problem. Asked to change out generator since still under warranty. As long as gen starts and carried load for several hours. Cummings will not do anything.

 

[Ivy]

I have already tried removing gas cap and driving coach. Still shuts down.

I keep coming back to your post. I feel that is the problem, even though I removed gas cap. When first purchased I was getting a check gas cap alert. Couldn’t find anthing wrong with cap. Had to clear code on coach a few times, then quit having alert. I have read that on a few times that an auxillary fuel pump may be needed to supply enough fuel to unit. This could be a fairly easy fix. Just not sure if voltage feeding fuel pump enough to carry two pumps. Has a 7.5 inline fuse to pump. Have 2 spare pumps I could use. I changed out previously with not luck. So they should be good.
Thanks for you help