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Onan Questions [message #337658] Sat, 06 October 2018 18:02 Go to next message
Melbo is currently offline  Melbo   United States
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Registered: August 2018
Location: Albuquerque NM
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I am trying to get my 6000 Onan up and running. The Starter engages. The fuel pump works. (Exploded the fuel line so that needs to be replaced) I am guessing that someone did something before I got the unit that I am not quite able to figure out. There are only two wires connected to the voltage regulator and there is a cut wire at the coil. From studying the wiring diagrams I know the coil wire does not go to the voltage regulator. Also the "5" wire is connected to one of the AC terminals on the voltage regulator and the wiring diagrams show it going to the B+ terminal. The other wire connected to the AC terminal has battery voltage all the time.

I kind of feel like Bob Seger -- working on mysteries without any clues.

All the wiring diagrams that I have been able to locate do not have the detail that I am needing to solve this. I am sure that they exist but I have not found one.

Any help or suggestions will be greatly appreciated.

Thanks

Melbo

Albuquerque NM Bus Conversion 1978 MCI 1973 GMC

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Re: Onan Questions [message #337659 is a reply to message #337658] Sat, 06 October 2018 18:13 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Registered: October 2006
Location: Woodstock, IL
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Three wires go to the VR. The two on the "twofer" stay connected together. Then tape it up. The single wire can get disconnected and taped up. This should get running signal to the board. I'm assuming you are using the house battery to crank and converter to charge it.

John Lebetski
Woodstock, IL
77 Eleganza II

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Re: Onan Questions [message #337660 is a reply to message #337659] Sat, 06 October 2018 18:34 Go to previous messageGo to next message
Melbo is currently offline  Melbo   United States
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Registered: August 2018
Location: Albuquerque NM
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John

Thank You for the response. I only have two wires at the regulator. One goes to the board and is connected to "5" terminal. It is connected to an "AC" terminal at the voltage regulator and from the wiring diagrams I have it appears that wire should go to the "B+" terminal. I believe the other wire connected to the regulator is from the alternator although I have not confirmed that by following the wire and disassembling the unit to see where it ends. According to the wiring diagrams I have (near as I can tell) that wire is correctly connected to an "AC" terminal. That wire the second one I have not determined the source of has voltage that matches my battery when tested to ground. The battery is connected to the cables in the compartment next to the generator. It is the only battery in the coach. The coach is disabled and the Onan is my starting point. So I am trying to figure out where each wire should go and where I am missing the wire from. Also the wire that was cut that is connected to the coil puzzles me.

Thanks

Melbo

Albuquerque NM Bus Conversion 1978 MCI 1973 GMC

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Re: [GMCnet] Onan Questions [message #337661 is a reply to message #337659] Sat, 06 October 2018 18:57 Go to previous messageGo to next message
powwerjon is currently offline  powwerjon   United States
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Registered: March 2013
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This is what you do to bypass the VR:

http://www.gmcmhphotos.com/photos/misc/p38302-onan-voltage-regulator-removal.html

JR Wright
Michigan


> On Oct 6, 2018, at 7:13 PM, John R. Lebetski wrote:
>
> Three wires go to the VR. The two on the "twofer" stay connected together. Then tape it up. The single wire can get disconnected and taped up. This
> should get running signal to the board. I'm assuming you are using the house battery to crank and converter to charge it.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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Re: [GMCnet] Onan Questions [message #337662 is a reply to message #337661] Sat, 06 October 2018 19:37 Go to previous messageGo to next message
Melbo is currently offline  Melbo   United States
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Registered: August 2018
Location: Albuquerque NM
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powwerjon

Thank you for the picture that helped clear some things up. I can see why it would seem that when I say I only have two wires it could be wires to two connectors BUT I really only have two wires. It looks like the third wire that I am missing comes from terminal "8" on the control board. I will get a chance tomorrow to do some further research on this. I keep learning as I go.

Is there a purpose for removing the onan voltage regulator? Is this something I should consider?

Thanks

Melbo

Albuquerque NM Bus Conversion 1978 MCI 1973 GMC

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Re: [GMCnet] Onan Questions [message #337664 is a reply to message #337662] Sat, 06 October 2018 20:54 Go to previous messageGo to next message
JerryW is currently offline  JerryW   United States
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Registered: August 2018
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That is not actually a voltage regulator. It is a battery charger.
There are two reasons to remove it.
1. It is a very slow charger and it will not put much current into the house battery. The battery charger / smart charger / buzz box that you have will charge the battery much faster and it will be powered up when you Onan is plugged into the breaker box.
2. If you have a smart charger it will detect another charging source and most (if not all) smart charger will not charge the battery if it detected another charging source connected to the battery. By disconnecting the little Onan charger you would get a fast charge instead of a trickle charge.

Emery Stora
77 Kingsley
Frederick, CO

> On Oct 6, 2018, at 6:37 PM, melmull@gmail.com wrote:
>
> powwerjon
>
> Thank you for the picture that helped clear some things up. I can see why it would seem that when I say I only have two wires it could be wires to
> two connectors BUT I really only have two wires. It looks like the third wire that I am missing comes from terminal "8" on the control board. I will
> get a chance tomorrow to do some further research on this. I keep learning as I go.
>
> Is there a purpose for removing the onan voltage regulator? Is this something I should consider?
>
> Thanks
>
> Melbo
> --
> Albuquerque NM Bus Conversion 1978 MCI 1973 GMC
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] Onan Questions [message #337683 is a reply to message #337664] Sun, 07 October 2018 20:18 Go to previous message
Melbo is currently offline  Melbo   United States
Messages: 144
Registered: August 2018
Location: Albuquerque NM
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Thank You Everyone for the help.

I found that there was a cut wire on the "hot" side of the ignition coil. After studying wiring diagrams and messing around with a meter for several hours on different days I discovered that the wire from the "6" terminal was NOT connected to the ignition coil. It seems that without that wire NOTHING will work. It "seems" that now I should have everything setup to work as it should. I have not had a chance to see if the "board" is good and does what it is supposed to because the Onan has never run yet. I need a fuel line to the carb. I now have power to the coil. Once the motor runs we will get a chance to see if it makes electricity.

Having fun figuring this out.

Once again thanks for the help

Melbo

Albuquerque NM Bus Conversion 1978 MCI 1973 GMC

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