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Onan question. [message #151366]

Fri, 02 December 2011 19:42

rssbob

Messages: 259
Registered: January 2004
Location: La Mesa, Ca. (San Diego a...

Karma: 0

Senior Member

When I bought this 78 is was headed for the scrap heap. Tons of deferred maintenance. But it runs like a top & drives straight so I figure it is worth fixing.

I noticed that when I installed the coach batteries the orange light on the remote generator start-switch came on and stayed on. I have a cut-off switch for the house batts so I disconnected the batts. Then I noticed that the orange light would also come on whenever I had the 403 running.

Yesterday, I filled the gas tanks for the first time and when I got home there was gas leaking from a line under the rear of the coach. Seems like the fuel line to the generator was broken where it went through the metal floor of the housing. I repaired that. Then I discovered the fuel pump was not bolted to the motor so I fixed that. Then I found one wire was disconnected from it's terminal so as soon as I put it back on the terminal the fuel pump came on. It wants to run all the time when the house batteries are connected and also if I have the 403 running. So there are 12 volts all the time on the fuel pump. The generator tries to start but acts like it is not getting enough fuel, all the while that fuel pump is clicking away. My next trick will be to clean the fuel filter on the bottom of the pump.

My question is, "why does that fuel pump run all the time"? Of course it is not running now because I disconnected the wire again until I get this sorted out.

Thanks

Bob Sobrito
78 Palm Beach
La Mesa, Ca

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Re: Onan question. [message #151371 is a reply to message #151366]

Fri, 02 December 2011 19:51

mike miller

Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon

Karma: 0

Senior Member

rssbob wrote on Fri, 02 December 2011 17:42

...
I noticed that when I installed the coach batteries the orange light on the remote generator start-switch came on and stayed on. I have a cut-off switch for the house batts so I disconnected the batts. Then I noticed that the orange light would also come on whenever I had the 403 running. ...

... Then I found one wire was disconnected from it's terminal so as soon as I put it back on the terminal the fuel pump came on. ...

Sounds like the symptoms of a Onan control board that has been jumped. (Often done to run the Onan with a bad control board, but should NOT be left that way.)

So... It may be jumped or mis-wired. Check that everything is connected correctly. If it is not jumped and is wired correctly, I suspect a bad board... most likely a bad relay.

Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo' http://m000035.blogspot.com

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Re: [GMCnet] Onan question. [message #151397 is a reply to message #151366]

Fri, 02 December 2011 23:00

jimk

Messages: 6734
Registered: July 2006
Location: Belmont, CA

Karma: 9

Senior Member

Bob,
Try pulling out the 5amp fuse from the board. Should that stop it
there can be" something wong" with the board or the switch or switches
are stuck.

On Fri, Dec 2, 2011 at 5:42 PM, Bob Sobrito <rssbob@cox.net> wrote:
>
>
> When I bought this 78 is was headed for the scrap heap. Tons of deferred maintenance. But it runs like a top & drives straight so I figure it is worth fixing.
>
> I noticed that when I installed the coach batteries the orange light on the remote generator start-switch came on and stayed on. I have a cut-off switch for the house batts so I disconnected the batts. Then I noticed that the orange light would also come on whenever I had the 403 running.
>
> Yesterday, I filled the gas tanks for the first time and when I got home there was gas leaking from a line under the rear of the coach. Seems like the fuel line to the generator was broken where it went through the metal floor of the housing. I repaired that. Then I discovered the fuel pump was not bolted to the motor so I fixed that. Then I found one wire was disconnected from it's terminal so as soon as I put it back on the terminal the fuel pump came on. It wants to run all the time when the house batteries are connected and also if I have the 403 running. So there are 12 volts all the time on the fuel pump. The generator tries to start but acts like it is not getting enough fuel, all the while that fuel pump is clicking away. My next trick will be to clean the fuel filter on the bottom of the pump.
>
> My question is, "why does that fuel pump run all the time"? Of course it is not running now because I disconnected the wire again until I get this sorted out.
>
> Thanks
> --
> Bob Sobrito
> 78 Palm Beach
> La Mesa, Ca
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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www.appliedgmc.com
1-800-752-7502

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Re: Onan question. [message #151411 is a reply to message #151366]

Sat, 03 December 2011 06:14

Matt Colie

Messages: 8547
Registered: March 2007
Location: S.E. Michigan

Karma: 7

Senior Member

rssbob wrote on Fri, 02 December 2011 20:42

Bob,

If that light and the fuel pump are getting power, so is the ignition. Unless it has been replaced, the points will burn if left powered when the engine is not running. This almost certainly is a control board issue. Unfortunately, we just lost our guy that knew these things better than anybody else.

Reason the light (and all the other things) on the Onan come on when you run the main engine is that the main engine alternator is powering up the house side system the way it should do.

And yes, pull the fuse on the control board as JimK suggested.

Congratulations on the rescue.

Matt

Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit

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Re: [GMCnet] Onan question. [message #151418 is a reply to message #151366]

Sat, 03 December 2011 08:48

jhbridges

Messages: 8412
Registered: May 2011
Location: Braselton ga

Karma: -74

Senior Member

This is an Onan or a Generac or what?� My Generac will run the pump and light the light any time the controller >thinks< it's on.� Which it does at some strange times.� Pressing the OFF side of the switch clears it.
�
--johnny
�
'76 transmode Norris - with generac
'76 Palm Beach - with Onan

________________________________
From: Bob Sobrito <rssbob@cox.net>
To: gmclist@temp.gmcnet.org
Sent: Friday, December 2, 2011 8:42 PM
Subject: [GMCnet] Onan question.

When I bought this 78 is was headed for the scrap heap.� Tons of deferred maintenance.� But it runs like a top & drives straight so I figure it is worth fixing.�

I noticed that when I installed the coach batteries the orange light on the remote generator start-switch came on and stayed on.� I have a cut-off switch for the house batts so I disconnected the batts.� Then I noticed that the orange light would also come on whenever I had the 403 running.

Yesterday, I filled the gas tanks for the first time and when I got home there was gas leaking from a line under the rear of the coach.� Seems like the fuel line to the generator was broken where it went through the metal floor of the housing.� I repaired that.� Then I discovered the fuel pump was not bolted to the motor so I fixed that.� Then I found one wire was disconnected from it's terminal so as soon as I put it back on the terminal the fuel pump came on.� It wants to run all the time when the house batteries are connected and also if I have the 403 running.� So there are 12 volts all the time on the fuel pump. The generator tries to start but acts like it is not getting enough fuel, all the while that fuel pump is clicking away.� My next trick will be to clean the fuel filter on the bottom of the pump.�

My question is, "why does that fuel pump run all the time"?� Of course it is not running now because I disconnected the wire again until I get this sorted out.

Thanks
--
Bob Sobrito
78 Palm Beach
La Mesa, Ca
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Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell

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Re: [GMCnet] Onan question. [message #151420 is a reply to message #151366]

Sat, 03 December 2011 08:56

Steven Ferguson

Messages: 3447
Registered: May 2006

Karma: 0

Senior Member

Bob,
Pull the connector and clean the terminals. If that doesn't do it, remove
the remote panel and check the connections. I bet you'll find the
connector on the rear of the onan that connects it to the remote panel is
suffering from corrosion. Ele contact cleaner works well in this case.
Pull the fuel pump when you remove the filter and give it a good cleaning
also.

On Fri, Dec 2, 2011 at 6:42 PM, Bob Sobrito <rssbob@cox.net> wrote:

>
>
> When I bought this 78 is was headed for the scrap heap. Tons of deferred
> maintenance. But it runs like a top & drives straight so I figure it is
> worth fixing.
>
> I noticed that when I installed the coach batteries the orange light on
> the remote generator start-switch came on and stayed on. I have a cut-off
> switch for the house batts so I disconnected the batts. Then I noticed
> that the orange light would also come on whenever I had the 403 running.
>
> Yesterday, I filled the gas tanks for the first time and when I got home
> there was gas leaking from a line under the rear of the coach. Seems like
> the fuel line to the generator was broken where it went through the metal
> floor of the housing. I repaired that. Then I discovered the fuel pump
> was not bolted to the motor so I fixed that. Then I found one wire was
> disconnected from it's terminal so as soon as I put it back on the terminal
> the fuel pump came on. It wants to run all the time when the house
> batteries are connected and also if I have the 403 running. So there are
> 12 volts all the time on the fuel pump. The generator tries to start but
> acts like it is not getting enough fuel, all the while that fuel pump is
> clicking away. My next trick will be to clean the fuel filter on the
> bottom of the pump.
>
> My question is, "why does that fuel pump run all the time"? Of course it
> is not running now because I disconnected the wire again until I get this
> sorted out.
>
> Thanks
> --
> Bob Sobrito
> 78 Palm Beach
> La Mesa, Ca
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>

--
Fathom the hypocrisy of a nation where every citizen must prove they have
health insurance......but not everyone has to prove they're a citizen.
Steve Ferguson
Sierra Vista, AZ
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Re: [GMCnet] Onan question. [message #151427 is a reply to message #151420]

Sat, 03 December 2011 09:39

rssbob

Messages: 259
Registered: January 2004
Location: La Mesa, Ca. (San Diego a...

Karma: 0

Senior Member

Thank you Steve, Mike, Matt, Jim and Johnny for your help. I will report on what I find.

On Dec 3, 2011, at 6:56 AM, Steven Ferguson wrote:

> Bob,
> Pull the connector and clean the terminals. If that doesn't do it, remove
> the remote panel and check the connections. I bet you'll find the
> connector on the rear of the onan that connects it to the remote panel is
> suffering from corrosion. Ele contact cleaner works well in this case.
> Pull the fuel pump when you remove the filter and give it a good cleaning
> also.
>
> On Fri, Dec 2, 2011 at 6:42 PM, Bob Sobrito <rssbob@cox.net> wrote:
>
>>
>>
>> When I bought this 78 is was headed for the scrap heap. Tons of deferred
>> maintenance. But it runs like a top & drives straight so I figure it is
>> worth fixing.
>>
>> I noticed that when I installed the coach batteries the orange light on
>> the remote generator start-switch came on and stayed on. I have a cut-off
>> switch for the house batts so I disconnected the batts. Then I noticed
>> that the orange light would also come on whenever I had the 403 running.
>>
>> Yesterday, I filled the gas tanks for the first time and when I got home
>> there was gas leaking from a line under the rear of the coach. Seems like
>> the fuel line to the generator was broken where it went through the metal
>> floor of the housing. I repaired that. Then I discovered the fuel pump
>> was not bolted to the motor so I fixed that. Then I found one wire was
>> disconnected from it's terminal so as soon as I put it back on the terminal
>> the fuel pump came on. It wants to run all the time when the house
>> batteries are connected and also if I have the 403 running. So there are
>> 12 volts all the time on the fuel pump. The generator tries to start but
>> acts like it is not getting enough fuel, all the while that fuel pump is
>> clicking away. My next trick will be to clean the fuel filter on the
>> bottom of the pump.
>>
>> My question is, "why does that fuel pump run all the time"? Of course it
>> is not running now because I disconnected the wire again until I get this
>> sorted out.
>>
>> Thanks
>> --
>> Bob Sobrito
>> 78 Palm Beach
>> La Mesa, Ca
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>>
>
>
>
> --
> Fathom the hypocrisy of a nation where every citizen must prove they have
> health insurance......but not everyone has to prove they're a citizen.
> Steve Ferguson
> Sierra Vista, AZ
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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Bob Sobrito
78 Palm Beach
La Mesa, Ca

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