Onan Generator Shuts Down

[Walter Pigeon]

Recently picked up a 2011 Georgetown with a Onan 5500 gen set... it shuts down after about 1/2 hour either driving or parked !!! Checked the usual suspect items... at a loss !! Can anyone advise ??
Thanx

[A32Deuce]

Could be overheating and shutting down. Several others have remarked about it. They came up with different ways to get the heat away from the genny.

[mirada13]

Originally Posted by A32Deuce

Could be overheating and shutting down. Several others have remarked about it. They came up with different ways to get the heat away from the genny.

could be low of oil or gas

[D W]

Originally Posted by Walter Pigeon

Recently picked up a 2011 Georgetown with a Onan 5500 gen set... it shuts down after about 1/2 hour either driving or parked !!! Checked the usual suspect items... at a loss !! Can anyone advise ??
Thanx

Sounds like a case of overheating. If I recall all of Onans 4K thru 7K that were compartmented had this problem. The Cummins fix was to install a heat shield between the engine and exhaust/muffler components so hot air did not get sucked back into the generator. These engines will flash trouble codes on the start switch letting you know why it shut down.

[gmann32]

Mine did that and I ended up replacing the Oman fuel pump on the generator with an airtex electric pump and no more problems! Will run for hours on end now!

[BBQGUY]

Sharing the error code could help.

Top 2 causes are: Weak fuel pump or recirculating air between the exhaust and intake causing the unit to over heat.

Airtex E11015 Electric Fuel Pump for Onan Generator Set is a direct replacement.

Installing an air diverter as mentioned above under the unit to separate the intake air from the exhaust really helps. A welding shop can fabricate and install it.

Other issues. Dirty Carburetor, clogged fuel or air filter, bad/old fuel, spark plugs need replacing, slip rings need cleaning, fuel line damaged or crimped, distance to the tank is to far to pull the fuel > adding an inline fuel pump near the tank solves the issue.

[Walter Pigeon]

Originally Posted by BBQGUY

Sharing the error code could help.

Top 2 causes are: Weak fuel pump or recirculating air between the exhaust and intake causing the unit to over heat.

Airtex E11015 Electric Fuel Pump for Onan Generator Set is a direct replacement.

Installing an air diverter as mentioned above under the unit to separate the intake air from the exhaust really helps. A welding shop can fabricate and install it.

Other issues. Dirty Carburetor, clogged fuel or air filter, bad/old fuel, spark plugs need replacing, slip rings need cleaning, fuel line damaged or crimped, distance to the tank is to far to pull the fuel > adding an inline fuel pump near the tank solves the issue.

Ran it for an hour today (no load) no problems... Will run it with the AC on tomorrow and see if it throws a code !!

[Vince and Charlette]

You probably already know this, but the generator is designed to shut down when the vehicle fuel tank reaches about 1/4 full. Your post seems to indicate this isn't the issue, but I just had to ask.

[jrowe0521]

need at least 1/4 tank of gas, check oil level (engine has low oil pressure shut off. even if oil level if ok, might happen on sharp turn or up steep hill), fuel pump. mine did that and replaced fuel pump fixed it. they are easy to access and replace. two wires to connect (12v+ and neg). be sure to make note of where they go before removing. also has high temp shut off. good luck.

[GlennSchau]

Mine did the same thing - new fuel pump [fixed the problem.

[Craiginok]

Mine did that too... Changed out the fuel pump and it hasn't been a problem since.

[Walter Pigeon]

Originally Posted by GlennSchau

Mine did the same thing - new fuel pump [fixed the problem.

Took a drive today , after about 35 minutes it shut down with no code... Sounded like it was fuel starvation, looks like a fuel pump is in order !!

[Secarider]

Originally Posted by Walter Pigeon

Took a drive today , after about 35 minutes it shut down with no code... Sounded like it was fuel starvation, looks like a fuel pump is in order !!

I have been dealing g with this issue for a couple months, even had Onan service look at it ran it for 32 hours no luck shutting down, I just got back a hour ago on a trip from Ohio to Cheyenne Wyoming, just when we hit Iowa temp in motorhome required generator about 93 degrees outside, started generator and it ran for 45 minutes and shut off, then would only run for 10 minutes everytime and shut off. Got to Cheyenne and bought a new fuel pump and filter replaced ran it for 1 1/2 hours with A/C on ran like a charm until later that afternoon when we where heading to a state park with no hookups, just guess, generator started acting up again. The next day when we got back I stopped by tractor supply got some carbr. cleaner and sprayed the crap out of it almost half a can. Before I sprayed carb I turned on both A/C units and the gen was surging and I could hear the invertor clicking everytime the generator surged, after I prayed it the generator ran ALMOSTsmooth with both a/c units on and could not hear and stumbling with just one a/c on, We left Cheyenne yesterday generator running for 6 straight hours with front a/c on an tv playing no issues. Fix complete, not so fast, this morning started generator turned on a/c while coming across Ill. after a hour, generator shuts down, start up again run for another hour shut down, outside temp was 79 degrees.

I am at the end of my rope, I disagree with overheating, if t was heat and the design, everyone who owns a 329DS or similar would be having the same issue. I know mine is fuel issue, Maybe it is carb, and I didn't get all the varnish out, as I mentioned before spraying it could not handle both a/c units, after I could still hear a slight miss with both unit running.

I cant take it back to onan even though it is under warranty, 100 miles round trip sucks, I am at a point to order a new carb. Don't know about trying this electric fuel pump, I have same issue before I change out and put oem version on.

[Walter Pigeon]

UPDATE: It threw a code 36... shut down without control input... no other !
ordering a new fuel pump, looks like a direct replacement, tracing the electrical connection to the fuel pump was a bitch !

Does anyone know what size spark plugs these things take ?? Onan 5.5 K (gas)

[jrowe0521]

i had a 2001 5k onan and the fuel pump fixed the problem. i bought it amazon for around $32. I now have a 2014 5.5k which has more covers over unit. I did see it from the under side. should be easy to access. two wires with different connectors, one mounting screw and two gas lines. should be not too bad. there are several available on amazon. the only difference is the fuel line connection. my 2001 had the output line with a sharp bend close to generator. others were straighter. you can always mount it elsewhere.

[Secarider]

Originally Posted by Walter Pigeon

UPDATE: It threw a code 36... shut down without control input... no other !
ordering a new fuel pump, looks like a direct replacement, tracing the electrical connection to the fuel pump was a bitch !

Does anyone know what size spark plugs these things take ?? Onan 5.5 K (gas)

Good luck with pump easy to change. I am leaning on changing carb. Pump did not fix my issue same as yours

[tailwind22]

Originally Posted by Secarider

I have been dealing g with this issue for a couple months, even had Onan service look at it ran it for 32 hours no luck shutting down, I just got back a hour ago on a trip from Ohio to Cheyenne Wyoming, just when we hit Iowa temp in motorhome required generator about 93 degrees outside, started generator and it ran for 45 minutes and shut off, then would only run for 10 minutes everytime and shut off. Got to Cheyenne and bought a new fuel pump and filter replaced ran it for 1 1/2 hours with A/C on ran like a charm until later that afternoon when we where heading to a state park with no hookups, just guess, generator started acting up again. The next day when we got back I stopped by tractor supply got some carbr. cleaner and sprayed the crap out of it almost half a can. Before I sprayed carb I turned on both A/C units and the gen was surging and I could hear the invertor clicking everytime the generator surged, after I prayed it the generator ran ALMOSTsmooth with both a/c units on and could not hear and stumbling with just one a/c on, We left Cheyenne yesterday generator running for 6 straight hours with front a/c on an tv playing no issues. Fix complete, not so fast, this morning started generator turned on a/c while coming across Ill. after a hour, generator shuts down, start up again run for another hour shut down, outside temp was 79 degrees.

I am at the end of my rope, I disagree with overheating, if t was heat and the design, everyone who owns a 329DS or similar would be having the same issue. I know mine is fuel issue, Maybe it is carb, and I didn't get all the varnish out, as I mentioned before spraying it could not handle both a/c units, after I could still hear a slight miss with both unit running.

I cant take it back to onan even though it is under warranty, 100 miles round trip sucks, I am at a point to order a new carb. Don't know about trying this electric fuel pump, I have same issue before I change out and put oem version on.

It happened with my brand new 2018 this weekend when needing the coach ac while driving. Before driving there was mild surging. I doubt mine is due to varnish, I thought maybe overheating.

[modemem]

Originally Posted by Craiginok

Mine did that too... Changed out the fuel pump and it hasn't been a problem since.

Back a few years when I owned a Class A had same problem...new fuel pump did the trick and easy to replace.

[Walter Pigeon]

Originally Posted by tailwind22

It happened with my brand new 2018 this weekend when needing the coach ac while driving. Before driving there was mild surging. I doubt mine is due to varnish, I thought maybe overheating.

Hopefully it will be taken care of under warranty... Let us know what they find... If they even tell you !!

[gmann32]

Replace it with an airtex e11015 electric fuel pump! Problem solved!