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RE: Onan Generator - Running Question
Campingking....thanks. The control board was the first thing replaced. The voltage regulator was checked using the procedure on the web link I attached. The flashing of field with 18 volts should have produced a 120 volt (or close to it) output voltage. So at this time I do not suspect the voltage regulator and expect to find something wrong internally.
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TheWrightMan
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06/01/08 11:06am |
Tech Issues
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RE: Onan Generator - Running Question
Thanks for the feedback Diesel......
But not generating 120 volts AC is my problem.....not sure how a governor rod would cause this.
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TheWrightMan
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05/31/08 12:22pm |
Tech Issues
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RE: Onan Generator - Running Question
Latest update.....
Here is the link to a handy document. http://www.rverscorner.com/onan.html
Checked the voltage regulator using the diode check function on a high quality digital meter. Here are the checks I made:
Open the control box cover and unplug the 12-pin regulator connector. With the meter on 'diode check', test between the following terminal pairs, connecting the positive lead to the first pin and the negative to the second. 5-9, 7-9, 10-9, 11-9, 12-9, 5-10, 5-11, 5-12, 5-3. Voltage regulator is bad if any pair indicates 'short' or 'open' except for pair 5-10, which should indicate open.
It passed this test.
Having removed the voltage regulator I did another test. While the generator was running by holding down the start button I flashed the field (F1-F2) through the brushes with two 9 volt batteries connected in series (18 volts).
Ohmic value across F1-F2 was checked prior to doing this, it was 24 ohms.
During the test, the voltage out of Q1-Q2 was 85 volts AC (this I believe is OK)and the voltage out of T1 & T2 -to- T3 & T4 was 65 volts AC (this certainly is not OK).
Removed the generator from the RV. Expect the problem is internal.
Anyone want to speculate on what the problem will be????
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TheWrightMan
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05/31/08 08:33am |
Tech Issues
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RE: Onan Generator - Running Question
Cummins-Onan shop can't test voltage regulator. Informed me that they swap it out with another one and if it solves the problem then it's bad.
Is there anyone out there who has the capabilities to test this regulator?
Give me a schematic of what's inside and I can do it.
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TheWrightMan
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05/29/08 06:32pm |
Tech Issues
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RE: Onan Generator - Running Question
Change of info....
Cleaned slip rings and now have 23 ohms across F1-F2.
CR9 was not bad after all.
Megged windings with 500 volt DC megger....
T1-T2 = O ohms T1 & T2 to gnd = .3 megohms
T3-T4 = 0 ohms
Jumped out oil pressure switch...no luck.
Only getting 42 volts AC out of T1 or T3 to T3 or T4 (Neutral).
Still won't stay runnning when you let go of the start button....
Brought the voltage regulator to Onan for testing. Tested capacitor before removing it and it tested good. No news from Onan until next week.
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TheWrightMan
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05/23/08 02:20pm |
Tech Issues
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RE: Onan Generator - Running Question
F1-F2 is 280 ohms. How does that sound??
What is the easiest way to polish the slipring??
I also think I found a bad rectifier (CR9) connected between one end of R7 and K1 (starter relay). Looking for some information for a replacement.
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TheWrightMan
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05/23/08 10:05am |
Tech Issues
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RE: Onan Generator - Running Question
Can't be a problem with the fuel line. The unit runs as long as the Start button is pushed in. But as soon as it's released it stops.
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TheWrightMan
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05/11/08 07:31pm |
Tech Issues
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RE: Onan Generator - Running Question
That's correct. The rotor is good. Brushes are free.
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TheWrightMan
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05/11/08 10:06am |
Tech Issues
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RE: Onan Generator - Running Question
I do have 11-12 VDC across F1 and F2.
Checked T1 and T3 with Ohm meter. Winding are closed. That's good.
Only 30 VAC out of T1 to Gnd and T3 to Gnd.
I suspect what ever the problem is that it is something that is intermittent, like a relay or bad connection. The reason, is because it has been doing this for sometime and the other day it ran fine.
Suggestions or next checks?
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TheWrightMan
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05/10/08 05:57pm |
Tech Issues
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RE: Onan Generator - Running Question
Jim,
Here is all the data:
Model 6.5NHEFA26100D
Serial F880134321
New local control board from Onan installed yesterday.
Oil switch checked with an Ohm meter.
Brushes fro F1 and F2 removed and inspected.
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TheWrightMan
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05/09/08 03:02pm |
Tech Issues
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Onan Generator - Running Question
I have a 1988 vintage 6.5 NHE Onan generator on an '88 motorhome. The problem is the generator will not stay running when I let go of the Start switch. I unplugged the remote switch from the control board and tried it from the local control switch. It has done this before on an intermitent basis but now it seems to be permanent. A few weeks ago it was running fine, powering both roof A/C units. Then it shutdown. I have checked the oil pressure switch, it's OK. I installed a new control board. The carbon brushes on F1 and F2 are OK, when it's running there is 24 volts AC across F1 and F2.
I have a schematic for this unit. Have electrical equipment and meters. Am electrically inclined so I will not bring this unit to someone to repair, unless there is a problem in the windings of the generator. I need to determine what is wrong, so I need your technical assistance on what to check.
What ouput voltage should I see at F1 and F2?
What is Q1 and Q2? What readings should I test for?
Waht is B1 and B2? What reading should I test for?
T2 and T4 are Neutral and Ground
T1 and T2 are the Phases. If they are open will the engine still run?
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TheWrightMan
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05/08/08 09:10pm |
Tech Issues
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Onan Starting and Running
I have an Onan 6.5NHEFA26100D in a 1988 Pace Arrow.
I am having problems with it stopping when I let go of the Remote Start button. The other day it ran fine for about 20 minutes supplying power to the roof A/C units. Then it stopped. Cranked it up again and it stops if I let go of the Start button.
First, does anyone know where I can get a "free" copy of a service manual or a wiring schematics for this Onan Generator?
I have lots of electrical experience and can troubleshoot it with a schematic.
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TheWrightMan
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04/07/08 07:57pm |
Tech Issues
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