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[GMCnet] Shut off valve on Onan [message #133328] Mon, 04 July 2011 18:51 Go to next message
Stacey and Bonnie Ant is currently offline  Stacey and Bonnie Ant   United States
Messages: 15
Registered: August 2009
Karma: 0
Junior Member
Hello GMC'ers Our Onan is finally running great....without the shut off
valve just before the fuel pump. Can anyone tell me what it does? and is
it necessary?

--
Stacey & Bonnie Antoniuk
78 Royale center kitchen
Geary, New Brunswick Canada
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Re: [GMCnet] Shut off valve on Onan [message #133330 is a reply to message #133328] Mon, 04 July 2011 19:11 Go to previous messageGo to next message
powerjon is currently offline  powerjon   United States
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Registered: January 2004
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Read here: http://gmcmotorhomeinfo.com/generator.html#solenoid

JR Wright


On Jul 4, 2011, at 7:51 PM, Stacey and Bonnie Antoniuk wrote:

> Hello GMC'ers Our Onan is finally running great....without the
> shut off
> valve just before the fuel pump. Can anyone tell me what it does?
> and is
> it necessary?
>
> --
> Stacey & Bonnie Antoniuk
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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
Re: [GMCnet] Shut off valve on Onan [message #133353 is a reply to message #133330] Tue, 05 July 2011 00:40 Go to previous messageGo to next message
mike miller   United States
Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon
Karma: 0
Senior Member
powerjon wrote on Mon, 04 July 2011 17:11

On Jul 4, 2011, at 7:51 PM, Stacey and Bonnie Antoniuk wrote:
> Hello GMC'ers Our Onan is finally running great....without the
> shut off
> valve just before the fuel pump. Can anyone tell me what it does?
> and is
> it necessary?

Read here: http://gmcmotorhomeinfo.com/generator.html#solenoid



Most people would say you do not NEED it.

It is part of the emissions control system.

The only time you would notice it missing is when your fuel tanks had to much pressure in them and over powered the float valve in the Onan carburetor.

IE: If your vent lines from your fuel tanks are clear, and the fuel separator in the driver's side rear wheel well is good and the carbon canisters in the wheel well under the passenger seat are not clogged... and you do not over fill the tank and then park on a hill (with the Onan carb lower than your tanks).... you shouldn't have a problem.

Many have removed the valve (including me on my 6k) and not had any issues.

Bottom line: I would not remove it unless it was bad, but I wouldn't worry about it if it was gone.


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
Re: [GMCnet] Shut off valve on Onan [message #133357 is a reply to message #133353] Tue, 05 July 2011 02:19 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Mike,

So the shutoff valve is the Onan's appendix, eh?

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426

-----Original Message-----
From: Mike Miller

Bottom line: I would not remove it unless it was bad, but I wouldn't worry
about it if it was gone.
--
Mike

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Shut off valve on Onan [message #133360 is a reply to message #133330] Tue, 05 July 2011 06:03 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
> Read here: http://gmcmotorhomeinfo.com/generator.html#solenoid
>
> JR Wright
>
> JR
the link should be
http://gmcmotorhome.info/generator.html#solenoid

wonder where you got the old one ?
gene



>
> On Jul 4, 2011, at 7:51 PM, Stacey and Bonnie Antoniuk wrote:
>
> > Hello GMC'ers Our Onan is finally running great....without the
> > shut off
> > valve just before the fuel pump. Can anyone tell me what it does?
> > and is
> > it necessary?
> >
> > --
> > Stacey & Bonnie Antoniuk
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
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Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] Shut off valve on Onan [message #133365 is a reply to message #133360] Tue, 05 July 2011 07:10 Go to previous message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
One possible use for the shut off valve on non-GM upfitted coaches is to keep the main GMC engine from sucking the Onan fuel line dry and then sucking air through the needle and seat valve of the Onan carb. This would not be a problem on a GM upfitted coach because GM used a separate fuel line from the tank ratht than teeing in to the same fuel pickup line from the tank.

I have never hear of anyone having having this problem. My 1976 GM upfitted coach does not have this valve.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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