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[GMCnet] Fuel tank Sending Unit [message #76668] Sun, 14 March 2010 22:02 Go to next message
Mark Torgerson is currently offline  Mark Torgerson   United States
Messages: 19
Registered: March 2010
Karma: 0
Junior Member
Hello

I currently have the fuel tanks out of my 73 Canyon Lands coach and would like to replace both the sending units.
The GMC International parts list shows the GM part as #6429128 - however this part number no longer exists in GM's databases.   

What is the brand/part number of the current recommended replacement for this part?  

Thank you in advance,


Sincerely,

Damon Freeman     



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Re: [GMCnet] Fuel tank Sending Unit [message #76671 is a reply to message #76668] Sun, 14 March 2010 22:18 Go to previous messageGo to next message
GMCNUSA is currently offline  GMCNUSA   United States
Messages: 283
Registered: August 2006
Location: Indianapolis, IN
Karma: 0
Senior Member
I currently have the fuel tanks out of my 73 Canyon Lands coach and would like to replace both the sending units.
The GMC International parts list shows the GM part as #6429128 - however this part number no longer exists in GM's databases.

What is the brand/part number of the current recommended replacement for this part?

Thank you in advance,


The best bet is to support one of our GMC suppliers and get it from one of them, it will be the correct one and the correct ohm value to work with our gauge. Installation is just the reverse of removal making sure the o ring stays in place. Be careful to put the vent hose on the pipe which does not go to the filter sock on bottom of sender. Jim Bounds in Florida at the COOP has them and Jim Kanamoto in California has them and check with the GMC supplier near you.


Larry Dilk
Indianapolis, IN
76 Eleganza II
Patterson 455,Turbo City TBI, Just LOVE It!
Re: [GMCnet] Fuel tank Sending Unit [message #76673 is a reply to message #76668] Sun, 14 March 2010 22:17 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Damon,

Here you go:

http://www.appliedgmc.com/prod.itml/icOid/773

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


-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Mark Torgerson
Sent: Monday, 15 March 2010 2:03 PM
To: gmclist@temp.gmcnet.org
Subject: [GMCnet] Fuel tank Sending Unit

Hello

I currently have the fuel tanks out of my 73 Canyon Lands coach and would
like to replace both the sending units.
The GMC International parts list shows the GM part as #6429128 - however
this part number no longer exists in GM's databases.   

What is the brand/part number of the current recommended replacement for
this part?  

Thank you in advance,


Sincerely,

Damon Freeman     



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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] Fuel tank Sending Unit [message #76748 is a reply to message #76673] Mon, 15 March 2010 14:49 Go to previous messageGo to next message
ggroth is currently offline  ggroth   United States
Messages: 282
Registered: February 2004
Location: Carson City NV
Karma: 0
Senior Member

Some guys just replace the Main (rear) tank sender. It really is all one needs. They are quite expensive.

geo groth '73 260 Sequoia Carson City Nevada 89703
Re: [GMCnet] Fuel tank Sending Unit [message #76755 is a reply to message #76748] Mon, 15 March 2010 16:25 Go to previous messageGo to next message
Mark Torgerson is currently offline  Mark Torgerson   United States
Messages: 19
Registered: March 2010
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Junior Member
Wow - Thank you - you are right.  As I understand it both tanks drain down at about the same rate ....

Thank you!     I'm still looking for one local here in Portland Oregon....

Damon
'73 Canyon Lands 




________________________________
From: George Groth <grggroth@sbcglobal.net>
To: gmclist@temp.gmcnet.org
Sent: Mon, March 15, 2010 12:49:57 PM
Subject: Re: [GMCnet] Fuel tank Sending Unit



Some guys just replace the Main (rear) tank sender.  It really is all one needs.  They are quite expensive.
--
geo groth '73 260 Sequoia
Carson City Nevada
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Re: [GMCnet] Fuel tank Sending Unit [message #76761 is a reply to message #76755] Mon, 15 March 2010 18:21 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Mark,

BE CAREFUL, there are ones out there that have a flat top plate and from
what I've read here they are no bloody good!

If you look at the ones that Jim K sells they look identical to the OEM
ones.

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


-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Mark Torgerson
Sent: Tuesday, 16 March 2010 8:26 AM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Fuel tank Sending Unit

Wow - Thank you - you are right.  As I understand it both tanks drain down
at about the same rate ....

Thank you!     I'm still looking for one local here in Portland Oregon....

Damon
'73 Canyon Lands 




________________________________
From: George Groth <grggroth@sbcglobal.net>
To: gmclist@temp.gmcnet.org
Sent: Mon, March 15, 2010 12:49:57 PM
Subject: Re: [GMCnet] Fuel tank Sending Unit



Some guys just replace the Main (rear) tank sender.  It really is all one
needs.  They are quite expensive.
--
geo groth '73 260 Sequoia
Carson City Nevada
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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] Fuel tank Sending Unit [message #76763 is a reply to message #76755] Mon, 15 March 2010 18:34 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member

On Mar 15, 2010, at 5:25 PM, Mark Torgerson wrote:

> Wow - Thank you - you are right. As I understand it both tanks
> drain down at about the same rate ....
>
> Thank you! I'm still looking for one local here in Portland
> Oregon....
>
> Damon
> '73 Canyon Lands
>


They only drain down evenly to about the half tank level. After that
if you are going up and down hills you will have absolutely no idea
if you have any fuel in the AUX tank and doin't have a sender in the
tank.
The fuel will flow from tank to tank. Usually from the AUX tank to
the MAIN tank due to the location of the fill inlets.

I know this from when I first got my GMC years ago. I had working
gauges on both tanks but when I switched to the AUX I found it was
almost empty. I walked 10 miles round trip to get a a can of gasoline.

Emery Stora
77 Kingsley
Santa Fe, NM

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Re: [GMCnet] Fuel tank Sending Unit [message #76772 is a reply to message #76763] Mon, 15 March 2010 19:36 Go to previous messageGo to next message
jayrabe is currently offline  jayrabe   United States
Messages: 509
Registered: June 2009
Location: Portland, OR
Karma: 0
Senior Member

But is there any way of telling how much is in the aux tank without actually switching? I once tried to check my reserve tank after doing some driving through the mountains, and when I switched to the aux tank the engine started to die, telling me that clearly the aux tank was nearly empty. It fired back up immediately upon switching back to the main tank, but all in all that's an experience I'm reluctant to repeat.

And is there any way of fixing the situation so that your aux tank doesn't get depleted when going up and down hills? Is there some great design advantage to the way the cross-over is plumbed? Are there options?

thanks,

J Rabe
76 Palm Beach
Portland, OR



> From: emerystora@mac.com
> To: gmclist@temp.gmcnet.org
> Date: Mon, 15 Mar 2010 19:34:59 -0400
> Subject: Re: [GMCnet] Fuel tank Sending Unit
>
>
> On Mar 15, 2010, at 5:25 PM, Mark Torgerson wrote:
>
> > Wow - Thank you - you are right. As I understand it both tanks
> > drain down at about the same rate ....
> >
> > Thank you! I'm still looking for one local here in Portland
> > Oregon....
> >
> > Damon
> > '73 Canyon Lands
> >
>
>
> They only drain down evenly to about the half tank level. After that
> if you are going up and down hills you will have absolutely no idea
> if you have any fuel in the AUX tank and doin't have a sender in the
> tank.
> The fuel will flow from tank to tank. Usually from the AUX tank to
> the MAIN tank due to the location of the fill inlets.
>
> I know this from when I first got my GMC years ago. I had working
> gauges on both tanks but when I switched to the AUX I found it was
> almost empty. I walked 10 miles round trip to get a a can of gasoline.
>
> Emery Stora
> 77 Kingsley
> Santa Fe, NM
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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Re: [GMCnet] Fuel tank Sending Unit [message #76773 is a reply to message #76748] Mon, 15 March 2010 19:38 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
Karma: 2
Senior Member
actually all of the gas ends up in the AUX tank. look here to see why

http://gmcmotorhome.info/tank.html

gene



On Mon, Mar 15, 2010 at 12:49 PM, George Groth <grggroth@sbcglobal.net>wrote:

>
>
> Some guys just replace the Main (rear) tank sender. It really is all one
> needs. They are quite expensive.
> --
> geo groth '73 260 Sequoia
> Carson City Nevada
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription 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
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] Fuel tank Sending Unit [message #76774 is a reply to message #76772] Mon, 15 March 2010 19:41 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
Karma: 2
Senior Member
I once tried to check my reserve tank after doing some driving through the
mountains, and when I switched to the aux tank the engine started to die,
telling me that clearly the aux tank was nearly empty.

prob a different problem, like the tank switch, the hoses, etc.

as you go up and down hill, almost all of the gas goes to the AUX tank,
which is why a lot of "old timers" always run on the AUX tank

gene


J Rabe
> 76 Palm Beach
> Portland, OR
>
>
>
> > From: emerystora@mac.com
> > To: gmclist@temp.gmcnet.org
> > Date: Mon, 15 Mar 2010 19:34:59 -0400
> > Subject: Re: [GMCnet] Fuel tank Sending Unit
> >
> >
> > On Mar 15, 2010, at 5:25 PM, Mark Torgerson wrote:
> >
> > > Wow - Thank you - you are right. As I understand it both tanks
> > > drain down at about the same rate ....
> > >
> > > Thank you! I'm still looking for one local here in Portland
> > > Oregon....
> > >
> > > Damon
> > > '73 Canyon Lands
> > >
> >
> >
> > They only drain down evenly to about the half tank level. After that
> > if you are going up and down hills you will have absolutely no idea
> > if you have any fuel in the AUX tank and doin't have a sender in the
> > tank.
> > The fuel will flow from tank to tank. Usually from the AUX tank to
> > the MAIN tank due to the location of the fill inlets.
> >
> > I know this from when I first got my GMC years ago. I had working
> > gauges on both tanks but when I switched to the AUX I found it was
> > almost empty. I walked 10 miles round trip to get a a can of gasoline.
> >
> > Emery Stora
> > 77 Kingsley
> > Santa Fe, NM
> >
> > _______________________________________________
> > GMCnet mailing list
> > List Information and Subscription Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
> _________________________________________________________________
> Hotmail: Trusted email with Microsoft’s powerful SPAM protection.
> http://clk.atdmt.com/GBL/go/210850552/direct/01/
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription 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
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] Fuel tank Sending Unit [message #76781 is a reply to message #76772] Mon, 15 March 2010 20:57 Go to previous messageGo to next message
Mark Torgerson is currently offline  Mark Torgerson   United States
Messages: 19
Registered: March 2010
Karma: 0
Junior Member
I was wondering the same thing.   

  What about a one way valve into the aux tank?


'73 Canyon Lands


________________________________
From: Jay Rabe <jayrabe@hotmail.com>
To: gmclist@temp.gmcnet.org
Sent: Mon, March 15, 2010 5:36:10 PM
Subject: Re: [GMCnet] Fuel tank Sending Unit


But is there any way of telling how much is in the aux tank without actually switching? I once tried to check my reserve tank after doing some driving through the mountains, and when I switched to the aux tank the engine started to die, telling me that clearly the aux tank was nearly empty. It fired back up immediately upon switching back to the main tank, but all in all that's an experience I'm reluctant to repeat.

And is there any way of fixing the situation so that your aux tank doesn't get depleted when going up and down hills? Is there some great design advantage to the way the cross-over is plumbed? Are there options?

thanks,

J Rabe
76 Palm Beach
Portland, OR



> From: emerystora@mac.com
> To: gmclist@temp.gmcnet.org
> Date: Mon, 15 Mar 2010 19:34:59 -0400
> Subject: Re: [GMCnet] Fuel tank Sending Unit
>
>
> On Mar 15, 2010, at 5:25 PM, Mark Torgerson wrote:
>
> > Wow - Thank you - you are right.  As I understand it both tanks 
> > drain down at about the same rate ....
> >
> > Thank you!    I'm still looking for one local here in Portland 
> > Oregon....
> >
> > Damon
> > '73 Canyon Lands
> >
>
>
> They only drain down evenly to about the half tank level.  After that 
> if you are going up and down hills you will  have absolutely no idea 
> if you have any fuel in the AUX tank and doin't have a sender in the 
> tank.
> The fuel will flow from tank to tank.  Usually from the AUX tank to 
> the MAIN tank due to the location of the fill inlets.
>
> I know this from when I first got my GMC years ago.  I had working 
> gauges on both tanks but when I switched to the AUX I found it was 
> almost empty.  I walked 10 miles round trip to get a a can of gasoline.
>
> Emery Stora
> 77 Kingsley
> Santa Fe, NM
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
                       
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Re: [GMCnet] Fuel tank Sending Unit [message #76788 is a reply to message #76781] Mon, 15 March 2010 22:37 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
Karma: 207
Senior Member
Wish I was home. I could help you out. Won't be back in Mo. for at least 3 weeks.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Fuel tank Sending Unit [message #76805 is a reply to message #76773] Tue, 16 March 2010 08:03 Go to previous messageGo to next message
GMCWiperMan is currently offline  GMCWiperMan   United States
Messages: 1248
Registered: December 2007
Karma: 1
Senior Member
Gene,

I've got a question about the last drawing, showing the Aux tank almost
completely filled when going downhill: With the vent line almost centered
fore and aft on top of the tank, won't the absence of a vent behind that
point keep the gas from filling much above that level?

Ken H.

On Mon, Mar 15, 2010 at 8:38 PM, Mr.erf ERFisher <mr.erfisher@gmail.com>wrote:

> actually all of the gas ends up in the AUX tank. look here to see why
>
> http://gmcmotorhome.info/tank.html
>
> gene
>
>
>
> On Mon, Mar 15, 2010 at 12:49 PM, George Groth <grggroth@sbcglobal.net
> >wrote:
>
> >
> >
> > Some guys just replace the Main (rear) tank sender. It really is all one
> > needs. They are quite expensive.
> > --
> > geo groth '73 260 Sequoia
> > Carson City Nevada
> > _______________________________________________
> > GMCnet mailing list
> > List Information and Subscription 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
> -------
> http://gmcmotorhome.info/
> Alternator Protection Cable
> http://gmcmotorhome.info/APC.html
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] Fuel tank Sending Unit [message #76811 is a reply to message #76805] Tue, 16 March 2010 08:26 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
Messages: 7117
Registered: August 2005
Karma: 2
Senior Member
There are several factors that change the dynamics of this tank system.

1 It depends upon how long your GMC is nose down or nose up..... flow rates
are a consideration. I know if you park nose down, your Onan will quit much
earlier ;>)

2 TBI systems return through the fill hose, and seem to return most of the
fuel to the AUX tank. May be a time / flow rate situation

3 and as you say, the vent lines will fill with fuel just to the same level
as the fuel in the tanks ( except in my coaches, where the vent / sendors
are leaking and if you park on a hill the fuel/ air, will leak out/in
through those.

but

in general, most of the fuel will end up in the AUX tank.

( Good move on not pushing the CAD. Life is tooooo short to create your own
pressure ;>)

gene


On Tue, Mar 16, 2010 at 6:03 AM, Ken Henderson <ken0henderson@gmail.com>wrote:

> Gene,
>
> I've got a question about the last drawing, showing the Aux tank almost
> completely filled when going downhill: With the vent line almost centered
> fore and aft on top of the tank, won't the absence of a vent behind that
> point keep the gas from filling much above that level?
>
> Ken H.
>
> On Mon, Mar 15, 2010 at 8:38 PM, Mr.erf ERFisher <mr.erfisher@gmail.com
> >wrote:
>
> > actually all of the gas ends up in the AUX tank. look here to see why
> >
> > http://gmcmotorhome.info/tank.html
> >
> > gene
> >
> >
> >
> > On Mon, Mar 15, 2010 at 12:49 PM, George Groth <grggroth@sbcglobal.net
> > >wrote:
> >
> > >
> > >
> > > Some guys just replace the Main (rear) tank sender. It really is all
> one
> > > needs. They are quite expensive.
> > > --
> > > geo groth '73 260 Sequoia
> > > Carson City Nevada
> > > _______________________________________________
> > > GMCnet mailing list
> > > List Information and Subscription 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
> > -------
> > http://gmcmotorhome.info/
> > Alternator Protection Cable
> > http://gmcmotorhome.info/APC.html
> > _______________________________________________
> > GMCnet mailing list
> > List Information and Subscription Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> >
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription 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
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
_______________________________________________
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Re: [GMCnet] Fuel tank Sending Unit [message #76816 is a reply to message #76805] Tue, 16 March 2010 09:03 Go to previous messageGo to next message
mike miller   United States
Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon
Karma: 0
Senior Member
GMCWiperMan wrote on Tue, 16 March 2010 06:03

Gene,

I've got a question about the last drawing, showing the Aux tank almost
completely filled when going downhill: With the vent line almost centered
fore and aft on top of the tank, won't the absence of a vent behind that
point keep the gas from filling much above that level?


I am not Gene, but I'll take a shot at this answer.

It puts fuel into the vent lines. Probably why they put int a fuel/vapor separator. Other than when you first top off, it probably doesn't happen that often. (How many have driven around with bad gaskets around the fuel senders?) It would take a pretty steep hill.

Not exactly what you asked about but related:

My thinking on why GM picked the front tank as the Aux tank.

On rolling hills, the system “pumps” the fuel into the front tank. To explain; on a down hill, fuel flows from the rear tank into the front tank. At the bottom of the hill (as the road levels out) the only fuel to return is the fuel more than the level of the connecting plumbing. (About ¼ tank.) If the switch from downhill to uphill is quick enough, it will “trap” even more of the fuel. (Not many of us drive our GMC's on roads like this... other than Rick D.!) This works best for rolling hills as it keeps at least ¼ tank in the front tank... if you have the fuel. It doesn't work as well on long uphill pulls.

End result is when you are low on fuel, you might need to swap back and forth a few times to keep from running out. It tells you that you should have stopped for fuel sooner.


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] Fuel tank Sending Unit [message #76828 is a reply to message #76816] Tue, 16 March 2010 11:53 Go to previous messageGo to next message
GMCWiperMan is currently offline  GMCWiperMan   United States
Messages: 1248
Registered: December 2007
Karma: 1
Senior Member
Certainly some fuel moves into the vent lines, but only up to the level of
the highest fuel level. That probably never approaches the height of the
liquid/vapor separator; the only time that should come into play is during
filling, since the fill tube does go above the separator.

If you look at the last photo, you'll see that on a downhill, the upper rear
of the front tank contains trapped air only in the uppermost corner; in
actuality, that corner should extend almost down to the center of the tank,
where the vent line allows air to escape. The only diminution of that
volume should be from slight compression of the trapped air.

JMHO,

Ken H.

On Tue, Mar 16, 2010 at 10:03 AM, Mike Miller <m000035@gmail.com> wrote:

>
>
> GMCWiperMan wrote on Tue, 16 March 2010 06&#58;03
> > Gene,
> >
> > I've got a question about the last drawing, showing the Aux tank almost
> > completely filled when going downhill: With the vent line almost
> centered
> > fore and aft on top of the tank, won't the absence of a vent behind that
> > point keep the gas from filling much above that level?
>
>
> I am not Gene, but I'll take a shot at this answer.
>
> It puts fuel into the vent lines. Probably why they put int a fuel/vapor
> separator. Other than when you first top off, it probably doesn't happen
> that often. (How many have driven around with bad gaskets around the fuel
> senders?) It would take a pretty steep hill.
>
...
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Re: [GMCnet] Fuel tank Sending Unit [message #76864 is a reply to message #76828] Tue, 16 March 2010 19:03 Go to previous messageGo to next message
gene1 is currently offline  gene1   United States
Messages: 50
Registered: February 2004
Location: Southern California
Karma: 0
Member
Ken,
I have a 76 here in CA, and it has Fuel Injection, is the 76 you have, have
a good Carb and air cleaner? Price?
Regards, Gene
----- Original Message -----
From: "Ken Henderson" <ken0henderson@gmail.com>
To: <gmclist@temp.gmcnet.org>
Sent: Tuesday, March 16, 2010 9:53 AM
Subject: Re: [GMCnet] Fuel tank Sending Unit


> Certainly some fuel moves into the vent lines, but only up to the level of
> the highest fuel level. That probably never approaches the height of the
> liquid/vapor separator; the only time that should come into play is during
> filling, since the fill tube does go above the separator.
>
> If you look at the last photo, you'll see that on a downhill, the upper
> rear
> of the front tank contains trapped air only in the uppermost corner; in
> actuality, that corner should extend almost down to the center of the
> tank,
> where the vent line allows air to escape. The only diminution of that
> volume should be from slight compression of the trapped air.
>
> JMHO,
>
> Ken H.
>
> On Tue, Mar 16, 2010 at 10:03 AM, Mike Miller <m000035@gmail.com> wrote:
>
>>
>>
>> GMCWiperMan wrote on Tue, 16 March 2010 06&#58;03
>> > Gene,
>> >
>> > I've got a question about the last drawing, showing the Aux tank almost
>> > completely filled when going downhill: With the vent line almost
>> centered
>> > fore and aft on top of the tank, won't the absence of a vent behind
>> > that
>> > point keep the gas from filling much above that level?
>>
>>
>> I am not Gene, but I'll take a shot at this answer.
>>
>> It puts fuel into the vent lines. Probably why they put int a fuel/vapor
>> separator. Other than when you first top off, it probably doesn't happen
>> that often. (How many have driven around with bad gaskets around the
>> fuel
>> senders?) It would take a pretty steep hill.
>>
> ...
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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Re: [GMCnet] Fuel tank Sending Unit [message #76880 is a reply to message #76864] Tue, 16 March 2010 20:20 Go to previous message
GMCWiperMan is currently offline  GMCWiperMan   United States
Messages: 1248
Registered: December 2007
Karma: 1
Senior Member
Gene,

I do have a '76 carb and air cleaner, but since I've installed the Cad 500,
I also have a 455 to mate them to so I'm not ready to let them go. Might
not qualify for California smog inspection anyway.

Sorry.

Ken H.

On Tue, Mar 16, 2010 at 8:03 PM, gene1@daygotours <gene1@daygotours.com>wrote:

> Ken,
> I have a 76 here in CA, and it has Fuel Injection, is the 76 you have, have
> a good Carb and air cleaner? Price?
> Regards, Gene
>
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