Hi could someone tell me what a coil ohms out to on a KY 4000 gen. The book said it about .05 i get .08 to .09, i am not sure if .08 is still in range or not. i m getting spark it runs but has a hard time. it has new carb, new plug, new pump, new rotor and stator. it just cant keep up when load is added. Its like a car out of time, it runs but no power.....Thanks for any help
onan 4000
- Thread starter bigguyone
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Does it attempt to speed up as the load comes on? The governor is supposed to match engine power to the electrical load, i.e.open the throttle to keep the rpms constant as the electrical load increases. If the governor doesn't do that, the engine stalls under load. However, if the governor tries to do that, i.e. opens the throttle but the engine doesn't respond, it still dies under load. Sometimes the difference between the two causes is hard to distinguish.
Here is a good source for help. Also there are YouTube videos on the 4000.
https://www.flightsystems.com/pdf/onan-rv-troubleshooting-guide.pdf
Here is a good source for help. Also there are YouTube videos on the 4000.
https://www.flightsystems.com/pdf/onan-rv-troubleshooting-guide.pdf
Henry J Fate
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Try manually throttling the generator using the throttle linkage at the carb. That linkage connects to the governor which is responsible for keeping the rpms at about 3600. If the engine responds well to your manual rpm increase then it becomes more likely you have a governor issue. You can check to make sure the governor linkage is free moving with the generator off also.
Another governor clue would be if you can see the governor linkage moving when the generator comes under load. It should be visible whether or not it is trying to move, moving or not moving at all.
Also... If you do not have a service manual, get one. Should be free from cummins/onan to an email address.
Another governor clue would be if you can see the governor linkage moving when the generator comes under load. It should be visible whether or not it is trying to move, moving or not moving at all.
Also... If you do not have a service manual, get one. Should be free from cummins/onan to an email address.
Yes i was able to see it and seems to work ok, the carb is wide open when i start it so cant get any more out of it. Its like the timing is off on a car slow to build up and no power. its not the vales didnt touch them, i even tried a new carb on it. it started this after the new rotor and stator was installed, i even pulled it back apart (and yes i did break the pin in the rotor and was replace). but all that seems to be in time. i was told the coil mite be bad so thats why i ask what ohms are ok for the coil.
Henry J Fate
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Best clue seems to be that the problems started following the stator and rotor replacement. Something is probably wrong there. Are you using factory parts or aftermarket parts? Do you have the factory service manual?
Cummins/Onan
800-286-6467
They can offer technical data as well as a factory service manual.
I am not sure if your coil reading is within factory specs. It sounds as though it may not be. Hopefully a member with knowledge of that number will respond.
If you call cummins/onan, have the model number and serial number when you call.
Cummins/Onan
800-286-6467
They can offer technical data as well as a factory service manual.
I am not sure if your coil reading is within factory specs. It sounds as though it may not be. Hopefully a member with knowledge of that number will respond.
If you call cummins/onan, have the model number and serial number when you call.
Yes using Cummins /Onan parts i talk with them and on the coil, and asked if the reading was ok, i never could get a clear answer, he said its about .05 never would say if .08/.09 was out of range. so at $100 i wanted to get more info on it. Spent enough as it is LOL
Henry J Fate
Well-known member
- Joined
- Jun 14, 2018
- Posts
- 2,292
I found these links that apparently show a history of generator problems for Bigguyone. There may be more out there. This should help members who will offer assistance.
http://www.rvforum.net/SMF_forum/index.php/topic,127257.msg1165856.html#msg1165856
http://www.rvforum.net/SMF_forum/index.php/topic,123444.msg1127391.html#msg1127391
http://www.rvforum.net/SMF_forum/index.php/topic,122993.msg1123318.html#msg1123318
http://www.rvforum.net/SMF_forum/index.php/topic,127257.msg1165856.html#msg1165856
http://www.rvforum.net/SMF_forum/index.php/topic,123444.msg1127391.html#msg1127391
http://www.rvforum.net/SMF_forum/index.php/topic,122993.msg1123318.html#msg1123318
Yes i have to say i have had my share of problems with this generator, first was told the reg was bad, so replaced it but turned out the stator was bad. Had to leave it be for a while to get money to get new rotor and stator. had to buy a new carb because it sat for a while. Now charging system seems ok, now eng dont want to run right, so yea me and this generator got some history......if only i knew .........if i ever get this done i will be able to get to use it.......
Hi, just wanted to thank all who gave advice. After replacing the stator, rotor and a few other things, reg, brushes and carb it would charge again but not run right. Took it back apart, Come to find out the pin in the rotor broke. It put the timing Out and made the engine sluggish. So I put a pin in the rotor and put it back together. It runs great now, and charges like it should. So thanks to all that helped...??..
