Onan oil change now not running

[kx125str99]

Hey guys I have an Onan microquiet 4000. Generator ran fine. Did an oil change and cleaned air filter and hasn’t ran since. Cleaned the carb and still won’t run correctly. It fires and runs for about 5-10 minutes then just instant die. Any ideas greatly appreciated.

[DrewE]

kx125str99 wrote:
Well when I was adjusting the screw I could hear the engine noise change. It got quieter so I’m gonna go ahead and jump off a limb here and say maybe it was over revving and going into a safety. Iv only had trailer for about 6 months. . When microwave would run it sounded the same as idle. No change. But now it runs like it should. Revs up when under a load. So I’m gonna gonna stick with the idle screw fixed my issue.

The Onan 4000 watt generator is supposed to run at a constant speed of 3600 rpm, not "rev up" under load—unless by that you mean getting a bit louder while running at (very nearly) the same speed. Since it's a mechanical governor, it will be running at a microscopically slower speed under load, but only a barely noticeable difference, maybe a few percent.

[kx125str99]

Well when I was adjusting the screw I could hear the engine noise change. It got quieter so I’m gonna go ahead and jump off a limb here and say maybe it was over revving and going into a safety. Iv only had trailer for about 6 months. . When microwave would run it sounded the same as idle. No change. But now it runs like it should. Revs up when under a load. So I’m gonna gonna stick with the idle screw fixed my issue.

[azrving]

dougrainer wrote:

azrving wrote:

dougrainer wrote:

kx125str99 wrote:
Hey guys so I finally had some time this weekend to get to storage and tinker with the generator. Ended up adjusting the idle screw. Runs bitchen now. Thanks for all the help guys.

1. Idle screw problem would NOT allow it to run 10 minutes and then die
2. You NEVER have to mess with the Idle screw at all. It is preset to a specific RPM(3600) and changing it will allow the voltage to change
3. It ran OK before Oil change? I doubt you messed with the Idle screw on a simple oil change.
4. While you THINK you found the problem, you have not. You need to check the NO load 120 voltage now, before you burn up any appliances. Doug

LOL, mind reader.

Not a Mind reader. Just KNOW what I am talking about and a Governor or Idle screw adjustment will not cause or fix the OP's problem. Whatever is wrong with his Genset, fixed itself, because changing the oil would not really cause his problem unless he failed to put the required amount of oil or overfilled the oil. Question, If you took your Auto to an oil change place and they changed the oil and then the Car died every 10 minutes and they stated they adjusted the idle screw and that fixed it, would you REALLY believe that fixed the problem? Doug

NO, I mean you were reading my mind. I agree 100 % with what you just wrote too. I have repaired small engines for 50 years so I know what you mean.

[T18skyguy]

I remember some years back a member had the same problem turned out the oil level sensor was bad.

[LittleBill]

dougrainer wrote:

azrving wrote:

dougrainer wrote:

kx125str99 wrote:
Hey guys so I finally had some time this weekend to get to storage and tinker with the generator. Ended up adjusting the idle screw. Runs bitchen now. Thanks for all the help guys.

1. Idle screw problem would NOT allow it to run 10 minutes and then die
2. You NEVER have to mess with the Idle screw at all. It is preset to a specific RPM(3600) and changing it will allow the voltage to change
3. It ran OK before Oil change? I doubt you messed with the Idle screw on a simple oil change.
4. While you THINK you found the problem, you have not. You need to check the NO load 120 voltage now, before you burn up any appliances. Doug

LOL, mind reader.

Not a Mind reader. Just KNOW what I am talking about and a Governor or Idle screw adjustment will not cause or fix the OP's problem. Whatever is wrong with his Genset, fixed itself, because changing the oil would not really cause his problem unless he failed to put the required amount of oil or overfilled the oil. Question, If you took your Auto to an oil change place and they changed the oil and then the Car died every 10 minutes and they stated they adjusted the idle screw and that fixed it, would you REALLY believe that fixed the problem? Doug

most people have no sense of troubleshooting and or are extremly gulable, i once told a girl i was dating that her tire just fell off, while we were driving at 70mph. 0 issue nothing, she almost flipped the car over trying to get pulled over and was hysterical.

needless to say i don't make that joke anymore....

[dougrainer]

azrving wrote:

dougrainer wrote:

kx125str99 wrote:
Hey guys so I finally had some time this weekend to get to storage and tinker with the generator. Ended up adjusting the idle screw. Runs bitchen now. Thanks for all the help guys.

1. Idle screw problem would NOT allow it to run 10 minutes and then die
2. You NEVER have to mess with the Idle screw at all. It is preset to a specific RPM(3600) and changing it will allow the voltage to change
3. It ran OK before Oil change? I doubt you messed with the Idle screw on a simple oil change.
4. While you THINK you found the problem, you have not. You need to check the NO load 120 voltage now, before you burn up any appliances. Doug

LOL, mind reader.

Not a Mind reader. Just KNOW what I am talking about and a Governor or Idle screw adjustment will not cause or fix the OP's problem. Whatever is wrong with his Genset, fixed itself, because changing the oil would not really cause his problem unless he failed to put the required amount of oil or overfilled the oil. Question, If you took your Auto to an oil change place and they changed the oil and then the Car died every 10 minutes and they stated they adjusted the idle screw and that fixed it, would you REALLY believe that fixed the problem? Doug

[Lynnmor]

Was that a idle mixture that you adjusted? Some assumed that you adjusted the governed speed.

[kx125str99]

Could be a fluke thing I’m not sure. But have tried before about 15 times and always dies since oil change.

[kx125str99]

Well considering my electrical background which is what I do everyday. I have already checked the voltage out. And in. And since I was there working on it. Witnessed it run for an hour while doing other things. I would say that adjusting the screw worked. Thanks.

[azrving]

dougrainer wrote:

kx125str99 wrote:
Hey guys so I finally had some time this weekend to get to storage and tinker with the generator. Ended up adjusting the idle screw. Runs bitchen now. Thanks for all the help guys.

1. Idle screw problem would NOT allow it to run 10 minutes and then die
2. You NEVER have to mess with the Idle screw at all. It is preset to a specific RPM(3600) and changing it will allow the voltage to change
3. It ran OK before Oil change? I doubt you messed with the Idle screw on a simple oil change.
4. While you THINK you found the problem, you have not. You need to check the NO load 120 voltage now, before you burn up any appliances. Doug

LOL, mind reader.

[dougrainer]

kx125str99 wrote:
Hey guys so I finally had some time this weekend to get to storage and tinker with the generator. Ended up adjusting the idle screw. Runs bitchen now. Thanks for all the help guys.

1. Idle screw problem would NOT allow it to run 10 minutes and then die
2. You NEVER have to mess with the Idle screw at all. It is preset to a specific RPM(3600) and changing it will allow the voltage to change
3. It ran OK before Oil change? I doubt you messed with the Idle screw on a simple oil change.
4. While you THINK you found the problem, you have not. You need to check the NO load 120 voltage now, before you burn up any appliances. Doug

[kx125str99]

Hey guys so I finally had some time this weekend to get to storage and tinker with the generator. Ended up adjusting the idle screw. Runs bitchen now. Thanks for all the help guys.

[STBRetired]

We have a 4KY in a utility trailer. If the oil level is at the minimum level, it will run for about 5 minutes until it gets enough oil thrown around to trip the low oil shutdown. Once it all drips back down, it will restart and run for another 5 minutes or so. Make sure you are at the max level on the dipstick (not over) rather than at the min.

[DrewE]

Wouldn't the oil level switch keep the engine from running at all, rather than let it run for 5-10 minutes before killing it? What's the use of a low oil switch if it lets you run for several minutes with insufficient lubrication?