This is how I fixed mine. In the case of: "I CAN'T START MY GENERATOR" It's has been two years since last time it was running, so I started by checking oil level full at gen (it won't start if low oil becouse of sensores), gasoline more than 1\4 tank in my RV (also safety censors), sparkplug checked for good spark, check the manual circuit braker (ON) at front RV engine compartment for current, also cleaned the carburetor and even installed new one but same situation, then checked wires and found some has been chewed by rats so I replaced them, by this time it started but stay runing only by keep pushing the switch on all the time, so I knew it was electrical problem from the engine itself, so I took the generator out from my RV to work in my garage, ( I did this by myself with some tools and old tricks) it's really heavy for one person. I disassemble the unit at my garage and started by removing the cover, then the cooling fan or flywheel unit (it's 2 items in one unit) until finally I was at the gen rotor and brushes assembly area and this is what I found: one more wire chewed by filthy rats plus the stinky rat nest in the middle of the generator motor coil, I fixed the wire and sanded the commutator copper contacts where the brushes are sitting becouse they were real duty with old urine from the rats. Then I assembled everything back together and bingo it's runing like a champion. For this project materials involved was about $60.00 including an aftermarket new carburetor and an harmonic balancer/steering wheel puller (available at any auto parts for $25.00) to pull the aluminum fan out and (flywheel). Just picture this: (Eny engine run smooth if gasoline and DC current aren't interrupted) so following this important principle you'll always find the problem to be fixed. Also if you have a onan microlite 4000 like mine, don't run it for more than a minute without the cover becouse you'll cook the engine real fast, also keep the eye on the aluminium fan and your fingers after cranking it in case you missing one or two members...just kidding. After testing the gen then put the air cooling assembly back and the rest of components including the cover and done!!! If this can help eaven one person save time and $$$ it'll make me more happy, thanks for reading!!!
We have a one year old Onan 2800 on our 1 year old Winnebago Travato. Our generator at 11 hours of use began surging and dying. All previous use was just exercising the unit. I did attempt to do a cleaning with Seafoam in the gasoline and a few sprays or carburetor cleaner into the intake. Actually it would idle when spraying then surge and die. That did not work so we took it to the Onan sevice center. I was reluctant to take the time to do that as we have been told that Onan usually denies the warranty coverage. So they did a check and the called and said it was the carburetor would be warrenty covered. What a relief I did a happy dance! Then an hour later they called back and said “sorry we found residue in the bowl and that Onan would not warranty the repair”. The price for removing the unit and replacing the carburetor was said to be $961. I asked for a better price and they did agree to $650. So looks like what I have been reading all over the internet is true, if you put gas in your generator and follow the suggestions for keeping it exercised there still will be no warranty coverage for your $3,500 generator.
Replace the carb with an actual Onan carb. You can try cleaning but usually this doesn't work. You can try an imported copycat but these usually don't come in adjusted properly or there are quality issues present. That's been my experience anyway. Peace.
Now this is how I fix mine, I did not want to spend 200 bucks before trying out a couple of cheap fixes, not sure which of the 3 things that I tried worked, but did not spend more than 10 bucks,,,first I bought some of the sea foam spray, and then I took off the air filter and spray, spray really good this stuff anywhere I could get it in, left over night, then I took the plunger valve on the bottom and made sure it was working properly and not stuck, and last I took the black plastic of the altitude adjusting screw, so that I could back off all the way and clean the jet off with some 000 steel wood fine, fine stuff, I kind of buff it,,,and put everything back together and it works fine now,,,NOW you can try one or the other, one at a time and see if it works,,,but I tried everything at once and is working fine now,,,( Microlite 4000)
Carb may be shot.... The replacement is pretty expensive. Try gunk carbreator cleaner...or Onan C9. Spray it in the throat of the carb, let it sit for an hour ....start the generator and spray small amounts in the throat of the carb until it almost stops running... Repeat several times until it runs smooth. It's either going to cost you,$10.00 or $300.00 .
Your generator is running very lean. Either adjust the idle fuel screw which most of the time it is sealed or, remove the black cap in the altitude needle screw and turn it slowly until the engine RPM is study
Amazing on the comments that says to replace the carburetor that It can’t be fixed etc. etc. The carburetor is not much different than a lawnmower carburetor. And onan carburetor is over priced by 10X. I have been rebuilding carburetors for years and if you think this is a complex carburetor, you should see the task that’s required to rebuild a carbureted motorcycle carburetor and there are four of them on a four-cylinder motorcycle. Yes, it is tedious, you cannot be ham-fisted, and you need the right tools and patience. At the bottom of the carburetor there is a drain screw. That is your best friend if you don’t want to have this problem. When you are done using the generator and won’t be using it for awhile, drain the carburetor. And at the beginning of the RV season open that drain screw before starting the generator and press the prime button to push the old fuel out of that long fuel line going to the gas tank way in the back of your RV. Use your nose to gauge the quality of that gasoline. This is good advice for all of your small engines. Somebody mentioned a pilot bearing minus generator only runs at one speed. Pilot jet is for slow speed operation. The problem lies at the bottom of the carburetor where the main jet is.
Same gen, same problem. Mine runs on lng. Replaced spark plug. Seating idle screw all the way in till snug Seated elevation screw all the way in till snug. Refer to specs from onan. Turn idle screw out 1.5 times Turn elevation screw out 1.75 times Open valves till it start running better. Then adjust idle screw. Mines running 95% better. Still surges ever so slightly but at least its running and charging the batterys steady
why would you go threw all that for something thats caused by a dirty jet in the carburetor from old or dirty gas? it just needs to be cleaned with some carb cleaner. and you should be all good if you didn't mess up a bunch of stuff trying to fiddle with all them things that dont useally cause a surging at idel problem
Darren Strutt how sure of this are you? Are you a mechanic? I'm having the same issue. Also may have screwed of the governor adjustment. How much does it cost to replace one?
In Canada they average 500cd$ for the carbs. We change lots of them. I work for an Onan certified shop in British Columbia. If you look very carefully at the carb where it joins onto the air filter housing. You will see the part number for the carb. It will be three numbers, a dash, then four numbers. Sometimes you need some brake clean and a toothbrush to clean it off enough to read it. If you have played with the governor or frequency adjustment, then you may need a shop to get it adjusted to the proper settings. IF you are lucky, you can change the carb without removing the plant from your RV, but I recommend getting help from an experienced technician to get the job done right. Hope this helps.
Darren Strutt I've already pulled it out of the camper. I'd love to take it to a real tech, and wouldn't really mind shelling out $500 usd if I could also get a tailpipe and muffler. Lol. Is there any other issues inherent to these generators?
Exercise them, that is what they like. Don't start them, make a piece of toast then shut them off. They like to be run hot under a good load. Everything you need to know is in this manual. I give one to each customer that comes in the shop. power.cummins.com/sites/default/files/literature/rv/F-1123-EN.pdf
Yep, fixed several small gas engines by cleaning out all the small passages. It's a tedious job, have to poke out the tiny orifices with bits of fishing monofilament and various solvents, then blow it out with Berryman's B12. Examine the carb exterior to find where all the passages have been drilled and then plugged to route around the main chamber. Take out the mixture screws and idle jets, count how many turns to seat them before removing so you can put them back in at the same position. Blow the solvent in both directions to really flush out the passage and orifices. In my experience Seafoam does nothing to dissolve the ethanol varnish, only B12 works well, although full strength Goof-Off will get some of it (the Xylene formula)
![🎤 ไปกันต่อออ! จับฉลากร้องเพลง x P’ #XXSIVK [EP.2] (1/2) เพลงของใครจึ้งสุดน้าา 💓🎤 #MXFRUIT](http://i.ytimg.com/vi/mLI_K0sAS4o/mqdefault.jpg)
This is how I fixed mine. In the case of:
"I CAN'T START MY GENERATOR"
It's has been two years since last time it was running, so I started by checking oil level full at gen (it won't start if low oil becouse of sensores), gasoline more than 1\4 tank in my RV (also safety censors), sparkplug checked for good spark, check the manual circuit braker (ON) at front RV engine compartment for current, also cleaned the carburetor and even installed new one but same situation, then checked wires and found some has been chewed by rats so I replaced them, by this time it started but stay runing only by keep pushing the switch on all the time, so I knew it was electrical problem from the engine itself, so I took the generator out from my RV to work in my garage, ( I did this by myself with some tools and old tricks) it's really heavy for one person.
I disassemble the unit at my garage and started by removing the cover, then the cooling fan or flywheel unit (it's 2 items in one unit) until finally I was at the gen rotor and brushes assembly area and this is what I found: one more wire chewed by filthy rats plus the stinky rat nest in the middle of the generator motor coil, I fixed the wire and sanded the commutator copper contacts where the brushes are sitting becouse they were real duty with old urine from the rats.
Then I assembled everything back together and bingo it's runing like a champion.
For this project materials involved was about $60.00 including an aftermarket new carburetor and an harmonic balancer/steering wheel puller (available at any auto parts for $25.00) to pull the aluminum fan out and (flywheel).
Just picture this: (Eny engine run smooth if gasoline and DC current aren't interrupted) so following this important principle you'll always find the problem to be fixed.
Also if you have a onan microlite 4000 like mine, don't run it for more than a minute without the cover becouse you'll cook the engine real fast, also keep the eye on the aluminium fan and your fingers after cranking it in case you missing one or two members...just kidding.
After testing the gen then put the air cooling assembly back and the rest of components including the cover and done!!!
If this can help eaven one person save time and $$$ it'll make me more happy, thanks for reading!!!
Thank you
We have a one year old Onan 2800 on our 1 year old Winnebago Travato. Our generator at 11 hours of use began surging and dying. All previous use was just exercising the unit. I did attempt to do a cleaning with Seafoam in the gasoline and a few sprays or carburetor cleaner into the intake. Actually it would idle when spraying then surge and die. That did not work so we took it to the Onan sevice center. I was reluctant to take the time to do that as we have been told that Onan usually denies the warranty coverage. So they did a check and the called and said it was the carburetor would be warrenty covered. What a relief I did a happy dance! Then an hour later they called back and said “sorry we found residue in the bowl and that Onan would not warranty the repair”. The price for removing the unit and replacing the carburetor was said to be $961. I asked for a better price and they did agree to $650. So looks like what I have been reading all over the internet is true, if you put gas in your generator and follow the suggestions for keeping it exercised there still will be no warranty coverage for your $3,500 generator.
They robbing customers. I think it’s the service dealer.
Replace the carb with an actual Onan carb. You can try cleaning but usually this doesn't work. You can try an imported copycat but these usually don't come in adjusted properly or there are quality issues present. That's been my experience anyway. Peace.
Now this is how I fix mine, I did not want to spend 200 bucks before trying out a couple of cheap fixes, not sure which of the 3 things that I tried worked, but did not spend more than 10 bucks,,,first I bought some of the sea foam spray, and then I took off the air filter and spray, spray really good this stuff anywhere I could get it in, left over night, then I took the plunger valve on the bottom and made sure it was working properly and not stuck, and last I took the black plastic of the altitude adjusting screw, so that I could back off all the way and clean the jet off with some 000 steel wood fine, fine stuff, I kind of buff it,,,and put everything back together and it works fine now,,,NOW you can try one or the other, one at a time and see if it works,,,but I tried everything at once and is working fine now,,,( Microlite 4000)
Carb may be shot.... The replacement is pretty expensive. Try gunk carbreator cleaner...or Onan C9. Spray it in the throat of the carb, let it sit for an hour ....start the generator and spray small amounts in the throat of the carb until it almost stops running... Repeat several times until it runs smooth. It's either going to cost you,$10.00 or $300.00 .
Your generator is running very lean. Either adjust the idle fuel screw which most of the time it is sealed or, remove the black cap in the altitude needle screw and turn it slowly until the engine RPM is study
Amazing on the comments that says to replace the carburetor that It can’t be fixed etc. etc. The carburetor is not much different than a lawnmower carburetor. And onan carburetor is over priced by 10X.
I have been rebuilding carburetors for years and if you think this is a complex carburetor, you should see the task that’s required to rebuild a carbureted motorcycle carburetor and there are four of them on a four-cylinder motorcycle. Yes, it is tedious, you cannot be ham-fisted, and you need the right tools and patience.
At the bottom of the carburetor there is a drain screw. That is your best friend if you don’t want to have this problem. When you are done using the generator and won’t be using it for awhile, drain the carburetor. And at the beginning of the RV season open that drain screw before starting the generator and press the prime button to push the old fuel out of that long fuel line going to the gas tank way in the back of your RV. Use your nose to gauge the quality of that gasoline. This is good advice for all of your small engines. Somebody mentioned a pilot bearing minus generator only runs at one speed. Pilot jet is for slow speed operation. The problem lies at the bottom of the carburetor where the main jet is.
This does not tell anything about how to FIX the issue.... just sayin'... complete waste of time.
He's asking for help
@@devinthomas4866 Oh really? I didn't understand it that way. If so, apologies.
Same gen, same problem. Mine runs on lng.
Replaced spark plug.
Seating idle screw all the way in till snug
Seated elevation screw all the way in till snug.
Refer to specs from onan. Turn idle screw out 1.5 times
Turn elevation screw out 1.75 times
Open valves till it start running better. Then adjust idle screw.
Mines running 95% better. Still surges ever so slightly but at least its running and charging the batterys steady
why would you go threw all that for something thats caused by a dirty jet in the carburetor from old or dirty gas? it just needs to be cleaned with some carb cleaner. and you should be all good if you didn't mess up a bunch of stuff trying to fiddle with all them things that dont useally cause a surging at idel problem
Carbs are the only fix for these units. I have changed tons of them. Don't try to clean or fix.... it will only break your heart.
Darren Strutt how sure of this are you? Are you a mechanic? I'm having the same issue. Also may have screwed of the governor adjustment. How much does it cost to replace one?
In Canada they average 500cd$ for the carbs. We change lots of them. I work for an Onan certified shop in British Columbia. If you look very carefully at the carb where it joins onto the air filter housing. You will see the part number for the carb. It will be three numbers, a dash, then four numbers. Sometimes you need some brake clean and a toothbrush to clean it off enough to read it. If you have played with the governor or frequency adjustment, then you may need a shop to get it adjusted to the proper settings. IF you are lucky, you can change the carb without removing the plant from your RV, but I recommend getting help from an experienced technician to get the job done right. Hope this helps.
Darren Strutt I've already pulled it out of the camper. I'd love to take it to a real tech, and wouldn't really mind shelling out $500 usd if I could also get a tailpipe and muffler. Lol. Is there any other issues inherent to these generators?
Exercise them, that is what they like. Don't start them, make a piece of toast then shut them off. They like to be run hot under a good load. Everything you need to know is in this manual. I give one to each customer that comes in the shop.
power.cummins.com/sites/default/files/literature/rv/F-1123-EN.pdf
Governor arm is cycling due to carb being gunked up. How did you fix it?
its doing that because you might of had old or dirty gas in it and it needs the jet in the carberator cleaned.
Having the same issue with my 2800 - did you ever resolve?
I ran sea foam 1:1 with gas and surging is mostly gone. It does help, have to repeat every year i guess
I have the same problem with my generator does anyone know how to fix it??
See my video Onan Microquiet 4000 Surge Fix. The 2800 is quite similar.
that didn't fix crap
main jet clogged remove carb and clean ....
dirty pilot circuit in the carb
Yep, fixed several small gas engines by cleaning out all the small passages. It's a tedious job, have to poke out the tiny orifices with bits of fishing monofilament and various solvents, then blow it out with Berryman's B12. Examine the carb exterior to find where all the passages have been drilled and then plugged to route around the main chamber. Take out the mixture screws and idle jets, count how many turns to seat them before removing so you can put them back in at the same position. Blow the solvent in both directions to really flush out the passage and orifices. In my experience Seafoam does nothing to dissolve the ethanol varnish, only B12 works well, although full strength Goof-Off will get some of it (the Xylene formula)
Replace the carb! Orifices are so small it's almost impossible to clean!
Uhmmmm, that’s not a fix. Once you remove your hand, it still surges right? Your carburetor is dirty and needs to be cleaned….. that’s the fix.
To fix this problem for ever we need to try all EPA for treason.
Why the heck do some people always have to make everything political?