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Home » Public Forums » GMCnet » Re: [GMCnet] ????Vapor Lock (yes, again)
Re: [GMCnet] ????Vapor Lock (yes, again) [message #88195] Sat, 12 June 2010 07:51 Go to next message
chucklexie is currently offline  chucklexie   United States
Messages: 44
Registered: June 2010
Karma: 0
Member
Wow, Charles, that is not a good situation for Texas owners!!!! I wonder if a TPI is an only real solution. An expensive one at that. However a new NON Quadrajet Carb may be a thought.
Chuck Ellis

---------- Original Message ----------
From: "Charles" <gcw13@sbcglobal.net>
To: <gmclist@temp.gmcnet.org>
Subject: Re: [GMCnet] ????Vapor Lock (yes, again)
Date: Sat, 12 Jun 2010 07:41:44 -0500

I had a marine fuel/water separator that I removed when
I eliminated the manual fuel pump. The reason I removed
it is that, where it was located there was about 8 to 10
more feet of fuel line with it installed. Fuel tanks have been
cleaned and sealed. Pick up and sending units replaced.
All the fuel lines and filters have been replaced. I have
also tried different electric fuel pumps. Even went so far
as to try an 8 PSI pump only to flood the carburetor when
I turned it on. I am not the only one having this problem.
Others in the area are having the same problem. One
added second electric pump, so when he switches tanks
the second pump activated. Another just completed
dropping tanks, replacing lines and filters. Little or no
change. Around 100 degree temperatures, we all have
the exact same problems Denny described. The only thing
I have seen mensioned on the list that I have not done or
tried is insulating the fuel tanks.
Still looking fo answers.
Charles


----- Original Message -----
From: "Ken Coit" <ktcoit@gmail.com>
To: <gmclist@temp.gmcnet.org>
Sent: Saturday, June 12, 2010 7:19 AM
Subject: Re: [GMCnet] ????Vapor Lock (yes, again)


> Water?? Could it be that the water in the tanks settles to the intake
> when
> the vehicle is not moving? Do you have a fuel/water separator?
>
> On Sat, Jun 12, 2010 at 8:07 AM, chucklexie@juno.com
> <chucklexie@juno.com>wrote:
>
>> I just purchased a 78 Royale and coming back home from refueling
>> yesterday
>> I had (what could be vapor locks) I was not sure I was going to get home.
>> I
>> had no problem when driving about 70 miles on the highway checking it
>> out.
>> In 5 miles it dies 5 times acting like it just ran out of gas. I was
>> thinking I may have a fuel line sucking air. It does have an electric
>> fuel
>> pump and mechanical. It does seem to work better on reserve tank setting
>> (maybe a coincidence). What is the TRUE test for this malady??? Anyone
>> have
>> suggestion? May just have purchased a pig in a poke. Beautiful coach but
>> not
>> muck faith in it right now.
>>
>>
>> Chuck
>>
>> ---------- Original Message ----------
>> From: Charles <gcw13@sbcglobal.net>
>> To: gmclist@temp.gmcnet.org
>> Subject: Re: [GMCnet] Vapor Lock (yes, again)
>> Date: Sat, 12 Jun 2010 06:38:42 -0500
>>
>>
>>
>>
>> Eugene,
>> Electric fuel pump is not the solution. I had both manual and electric
>> and
>> still had vapor lock. Lock on manual and electric would only sometimes
>> take
>> care of the problem. I removed manual pump and went strictly with
>> electric.
>> Still have problem. Electric pump is just forward of the tank selector
>> valve
>> about
>> three inches. What do we do now? I am ready to try almost any thing and I
>> don't have mountains.
>> Charles
>> _______________________________________________
>> 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
>>
>
>
>
> --
> Ken Coit, ND7N
> Raleigh, NC
> Parfait Royale
> 1978 Royale Rear Bath, 403, 3.07
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

_______________________________________________
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Re: [GMCnet] ????Vapor Lock (yes, again) [message #88198 is a reply to message #88195] Sat, 12 June 2010 08:02 Go to previous messageGo to next message
Sandra Price is currently offline  Sandra Price   United States
Messages: 709
Registered: May 2006
Karma: 1
Senior Member
Charles, have you ever considered pulling the intake manifold and blocking
the exhaust passage off coming out the heads? I have EFI with blocked
passages and have never ever had vapor lock. I even put the costly
insulation on the tanks--it blew off on the first trip after. When we
stopped to refuel after coming across from Riudosa at 105 degrees, we had no
vapor lock; however, the fuel cap blew off when I removed it. It was hot!

Good luck!

Bob Price
On Sat, Jun 12, 2010 at 7:51 AM, chucklexie@juno.com <chucklexie@juno.com>wrote:

> Wow, Charles, that is not a good situation for Texas owners!!!! I wonder if
> a TPI is an only real solution. An expensive one at that. However a new NON
> Quadrajet Carb may be a thought.
> Chuck Ellis
>
> ---------- Original Message ----------
> From: "Charles" <gcw13@sbcglobal.net>
> To: <gmclist@temp.gmcnet.org>
> Subject: Re: [GMCnet] ????Vapor Lock (yes, again)
> Date: Sat, 12 Jun 2010 07:41:44 -0500
>
> I had a marine fuel/water separator that I removed when
> I eliminated the manual fuel pump. The reason I removed
> it is that, where it was located there was about 8 to 10
> more feet of fuel line with it installed. Fuel tanks have been
> cleaned and sealed. Pick up and sending units replaced.
> All the fuel lines and filters have been replaced. I have
> also tried different electric fuel pumps. Even went so far
> as to try an 8 PSI pump only to flood the carburetor when
> I turned it on. I am not the only one having this problem.
> Others in the area are having the same problem. One
> added second electric pump, so when he switches tanks
> the second pump activated. Another just completed
> dropping tanks, replacing lines and filters. Little or no
> change. Around 100 degree temperatures, we all have
> the exact same problems Denny described. The only thing
> I have seen mensioned on the list that I have not done or
> tried is insulating the fuel tanks.
> Still looking fo answers.
> Charles
>
>
> ----- Original Message -----
> From: "Ken Coit" <ktcoit@gmail.com>
> To: <gmclist@temp.gmcnet.org>
> Sent: Saturday, June 12, 2010 7:19 AM
> Subject: Re: [GMCnet] ????Vapor Lock (yes, again)
>
>
> > Water?? Could it be that the water in the tanks settles to the intake
> > when
> > the vehicle is not moving? Do you have a fuel/water separator?
> >
> > On Sat, Jun 12, 2010 at 8:07 AM, chucklexie@juno.com
> > <chucklexie@juno.com>wrote:
> >
> >> I just purchased a 78 Royale and coming back home from refueling
> >> yesterday
> >> I had (what could be vapor locks) I was not sure I was going to get
> home.
> >> I
> >> had no problem when driving about 70 miles on the highway checking it
> >> out.
> >> In 5 miles it dies 5 times acting like it just ran out of gas. I was
> >> thinking I may have a fuel line sucking air. It does have an electric
> >> fuel
> >> pump and mechanical. It does seem to work better on reserve tank setting
> >> (maybe a coincidence). What is the TRUE test for this malady??? Anyone
> >> have
> >> suggestion? May just have purchased a pig in a poke. Beautiful coach but
> >> not
> >> muck faith in it right now.
> >>
> >>
> >> Chuck
> >>
> >> ---------- Original Message ----------
> >> From: Charles <gcw13@sbcglobal.net>
> >> To: gmclist@temp.gmcnet.org
> >> Subject: Re: [GMCnet] Vapor Lock (yes, again)
> >> Date: Sat, 12 Jun 2010 06:38:42 -0500
> >>
> >>
> >>
> >>
> >> Eugene,
> >> Electric fuel pump is not the solution. I had both manual and electric
> >> and
> >> still had vapor lock. Lock on manual and electric would only sometimes
> >> take
> >> care of the problem. I removed manual pump and went strictly with
> >> electric.
> >> Still have problem. Electric pump is just forward of the tank selector
> >> valve
> >> about
> >> three inches. What do we do now? I am ready to try almost any thing and
> I
> >> don't have mountains.
> >> Charles
> >> _______________________________________________
> >> 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
> >>
> >
> >
> >
> > --
> > Ken Coit, ND7N
> > Raleigh, NC
> > Parfait Royale
> > 1978 Royale Rear Bath, 403, 3.07
> > _______________________________________________
> > 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
>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
IN GOD WE TRUST!

Sandra and Bob in the 51st Year of our State of Marriage
“Life’s a Trip” in “The Roadhouse”
’73 Painted Desert
Huntsville, TX

Finally, all of you, live in harmony with one another, be sympathetic, love
as brothers, be compassionate and humble. Do not repay evil with evil or
insult with insult, but with blessing, because to this you were called so
that you may inherit a blessing. --1 Peter 3:8-9
_______________________________________________
GMCnet mailing list
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Re: [GMCnet] ????Vapor Lock (yes, again) [message #88214 is a reply to message #88198] Sat, 12 June 2010 08:48 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
Messages: 4452
Registered: November 2009
Karma: -8
Senior Member

Regarding fuel cap blowing off. Should we be
thinking about going to a venting fuel cap?
Are our fuel pump trying to work against a
huge vacuum???


* Mac Macdonald *
* USAF, Retired *
* Oklahoma City *
** "Money Pit" **
* '76 ex - P.B. *


----------------------------------------
> Date: Sat, 12 Jun 2010 08:02:37 -0500
> From: bsprice9359@gmail.com
> To: gmclist@temp.gmcnet.org
> Subject: Re: [GMCnet] ????Vapor Lock (yes, again)
>
> Charles, have you ever considered pulling the intake manifold and blocking
> the exhaust passage off coming out the heads? I have EFI with blocked
> passages and have never ever had vapor lock. I even put the costly
> insulation on the tanks--it blew off on the first trip after. When we
> stopped to refuel after coming across from Riudosa at 105 degrees, we had no
> vapor lock; however, the fuel cap blew off when I removed it. It was hot!
>
> Good luck!
>
> Bob Price
> On Sat, Jun 12, 2010 at 7:51 AM, chucklexie@juno.com wrote:
>
>> Wow, Charles, that is not a good situation for Texas owners!!!! I wonder if
>> a TPI is an only real solution. An expensive one at that. However a new NON
>> Quadrajet Carb may be a thought.
>> Chuck Ellis
>>
>> ---------- Original Message ----------
>> From: "Charles"
>> To:
>> Subject: Re: [GMCnet] ????Vapor Lock (yes, again)
>> Date: Sat, 12 Jun 2010 07:41:44 -0500
>>
>> I had a marine fuel/water separator that I removed when
>> I eliminated the manual fuel pump. The reason I removed
>> it is that, where it was located there was about 8 to 10
>> more feet of fuel line with it installed. Fuel tanks have been
>> cleaned and sealed. Pick up and sending units replaced.
>> All the fuel lines and filters have been replaced. I have
>> also tried different electric fuel pumps. Even went so far
>> as to try an 8 PSI pump only to flood the carburetor when
>> I turned it on. I am not the only one having this problem.
>> Others in the area are having the same problem. One
>> added second electric pump, so when he switches tanks
>> the second pump activated. Another just completed
>> dropping tanks, replacing lines and filters. Little or no
>> change. Around 100 degree temperatures, we all have
>> the exact same problems Denny described. The only thing
>> I have seen mensioned on the list that I have not done or
>> tried is insulating the fuel tanks.
>> Still looking fo answers.
>> Charles
>>
>>
>> ----- Original Message -----
>> From: "Ken Coit"
>> To:
>> Sent: Saturday, June 12, 2010 7:19 AM
>> Subject: Re: [GMCnet] ????Vapor Lock (yes, again)
>>
>>
>>> Water?? Could it be that the water in the tanks settles to the intake
>>> when
>>> the vehicle is not moving? Do you have a fuel/water separator?
>>>
>>> On Sat, Jun 12, 2010 at 8:07 AM, chucklexie@juno.com
>>> wrote:
>>>
>>>> I just purchased a 78 Royale and coming back home from refueling
>>>> yesterday
>>>> I had (what could be vapor locks) I was not sure I was going to get
>> home.
>>>> I
>>>> had no problem when driving about 70 miles on the highway checking it
>>>> out.
>>>> In 5 miles it dies 5 times acting like it just ran out of gas. I was
>>>> thinking I may have a fuel line sucking air. It does have an electric
>>>> fuel
>>>> pump and mechanical. It does seem to work better on reserve tank setting
>>>> (maybe a coincidence). What is the TRUE test for this malady??? Anyone
>>>> have
>>>> suggestion? May just have purchased a pig in a poke. Beautiful coach but
>>>> not
>>>> muck faith in it right now.
>>>>
>>>>
>>>> Chuck
>>>>
>>>> ---------- Original Message ----------
>>>> From: Charles
>>>> To: gmclist@temp.gmcnet.org
>>>> Subject: Re: [GMCnet] Vapor Lock (yes, again)
>>>> Date: Sat, 12 Jun 2010 06:38:42 -0500
>>>>
>>>>
>>>>
>>>>
>>>> Eugene,
>>>> Electric fuel pump is not the solution. I had both manual and electric
>>>> and
>>>> still had vapor lock. Lock on manual and electric would only sometimes
>>>> take
>>>> care of the problem. I removed manual pump and went strictly with
>>>> electric.
>>>> Still have problem. Electric pump is just forward of the tank selector
>>>> valve
>>>> about
>>>> three inches. What do we do now? I am ready to try almost any thing and
>> I
>>>> don't have mountains.
>>>> Charles
>>>> _______________________________________________
>>>> 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
>>>>
>>>
>>>
>>>
>>> --
>>> Ken Coit, ND7N
>>> Raleigh, NC
>>> Parfait Royale
>>> 1978 Royale Rear Bath, 403, 3.07
>>> _______________________________________________
>>> 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
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> List Information and Subscription Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>>
>
>
>
> --
> IN GOD WE TRUST!
>
> Sandra and Bob in the 51st Year of our State of Marriage
> “Life’s a Trip” in “The Roadhouse”
> ’73 Painted Desert
> Huntsville, TX
>
> Finally, all of you, live in harmony with one another, be sympathetic, love
> as brothers, be compassionate and humble. Do not repay evil with evil or
> insult with insult, but with blessing, because to this you were called so
> that you may inherit a blessing. --1 Peter 3:8-9
> _______________________________________________
> 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:
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Re: [GMCnet] ????Vapor Lock (yes, again) [message #88219 is a reply to message #88198] Sat, 12 June 2010 09:28 Go to previous messageGo to next message
Charles is currently offline  Charles   United States
Messages: 455
Registered: January 2004
Karma: 0
Senior Member
Bob and Sandra,
Intake has been blocked off since 2002 when I put in the new engine.
EFI is really a high dollar fix. $1.275.00 last time I checked. There has
to be something cheaper. I,m trying to call John Shapre for more info
on his suggestion. Lines busy
Charles

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Charles Wersal
Duncanville, Texas
26 foot 1975 Glenbrook
Pandora's Box

Re: [GMCnet] ????Vapor Lock (yes, again) [message #88222 is a reply to message #88219] Sat, 12 June 2010 09:42 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
Messages: 1085
Registered: October 2008
Location: Colfax, CA
Karma: 11
Senior Member
Charles wrote on Sat, 12 June 2010 07:28

Bob and Sandra,
Intake has been blocked off since 2002 when I put in the new engine.
EFI is really a high dollar fix. $1.275.00 last time I checked. There has
to be something cheaper.
Charles





Has anyone here tried fuel coolers? They make me a little nervous, as you sure would want them protected. I also wouldn't want one in front of the radiator, because if it got hit by a rock, gas would be sprayed by the fan.

The first one here doesn't look like it could provide much, but the cost is right.

http://www.google.com/products/catalog?hl=en&rlz=&q=fuel+cooler&um=1&ie=UTF-8&cid=9740907708678323321&ei=1ZoTTKqPC6XinQe7uoiCD g&sa=X&oi=product_catalog_result&ct=result&resnum=2&ved=0CCMQ8wIwAQ#

Second is more like a powersteering cooler. I considered one when running my first TBI and the tanks built so much pressure. (By the way, I believe a cap in good shape is set to pop off at 3 lbs. The system also lets air back in to the tanks so there is a little vacuum but not extensive.)

http://www.amazon.com/Flex-lite-4136-Fuel-Cooler/dp/B000CNLD9C


You can do your own search on Google: Fuel Cooler


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
Re: [GMCnet] ????Vapor Lock (yes, again) [message #88245 is a reply to message #88222] Sat, 12 June 2010 12:35 Go to previous messageGo to next message
hal kading is currently offline  hal kading   United States
Messages: 642
Registered: February 2004
Location: Las Cruces NM
Karma: 4
Senior Member
If you have either vacuum or pressure in the tanks you have a venting problem.

Hal Kading Las Cruces NM
Re: [GMCnet] ????Vapor Lock (yes, again) [message #88258 is a reply to message #88245] Sat, 12 June 2010 14:47 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
I think your sock filters in the tank are almost plugged.
Take an air hose and reverse blow into both tanks with the fill cap loose.
All the deposits in the tank are being pulled into the new fuel with
new additives and alcohol.

On Sat, Jun 12, 2010 at 10:35 AM, Hal Kading <halkading@fastwave.biz> wrote:
>
>
> If you have either vacuum or pressure in the tanks you have a venting problem.
>
> Hal Kading Las Cruces NM
> _______________________________________________
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--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] ????Vapor Lock (yes, again) [message #88353 is a reply to message #88214] Sun, 13 June 2010 08:55 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
k2gkk wrote on Sat, 12 June 2010 09:48


Regarding fuel cap blowing off. Should we be thinking about going to a venting fuel cap?
Are our fuel pump trying to work against a huge vacuum???

* Mac Macdonald *

Mac,

Blowing off is pressure.

If it was a vacuum, it would be sucking the cap on. A properly functioning system will not have negative pressure.

As a wrong response to California smog, fuel systems have been prevented from allowing fuel vapors to vent to atmosphere since 1968 (IIRC). The systems as old as ours never envisioned something as poorly conceived as E-10 fuel.

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
Re: [GMCnet] ????Vapor Lock (yes, again) [message #88708 is a reply to message #88214] Tue, 15 June 2010 16:22 Go to previous messageGo to next message
Bob de Kruyff   United States
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
Senior Member
""Regarding fuel cap blowing off. Should we be
thinking about going to a venting fuel cap?
Are our fuel pump trying to work against a
huge vacuum???""

Our caps are vented. They relieve at 1 to 1/2 psi pressure and also vent under a slight vacuum. I have seen many defective or incorrect ones.




Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: [GMCnet] ????Vapor Lock (yes, again) [message #88713 is a reply to message #88708] Tue, 15 June 2010 16:40 Go to previous messageGo to next message
Ken Coit is currently offline  Ken Coit   United States
Messages: 151
Registered: November 2005
Karma: 0
Senior Member
OH! Maybe I don't have the right filler cap either.

On Tue, Jun 15, 2010 at 5:22 PM, Bob de Kruyff <NEXT2POOL@aol.com> wrote:

>
>
> ""Regarding fuel cap blowing off. Should we be
> thinking about going to a venting fuel cap?
> Are our fuel pump trying to work against a
> huge vacuum???""
>
> Our caps are vented. They relieve at 1 to 1/2 psi pressure and also vent
> under a slight vacuum. I have seen many defective or incorrect ones.
>
>
>
> --
> Bob de Kruyff
> 78 Eleganza
> Chandler, AZ
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Ken Coit, ND7N
Raleigh, NC
Parfait Royale
1978 Royale Rear Bath, 403, 3.07
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Re: [GMCnet] ????Vapor Lock (yes, again) [message #88718 is a reply to message #88708] Tue, 15 June 2010 17:04 Go to previous messageGo to next message
psakw is currently offline  psakw   United States
Messages: 61
Registered: February 2010
Karma: 0
Member
Do you know the part number for the right cap?

Paul A
73 Sequoia
Key West, Florida
Re: [GMCnet] ????Vapor Lock (yes, again) [message #88722 is a reply to message #88708] Tue, 15 June 2010 17:07 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Very common problem, not having the correct cap. The tanks are supposed to
vent through the fuel liquid/vapor separator located in the drivers side
rear wheel well near the forward tire, from there to the charcoal cannister
located behind the inner fender on the passenger side, and from there to the
air cleaner or carb air bonnet. That larger line that goes up the fuel
filler neck is supposed to burp a small amount of fuel through it when the
tanks are nearly full. That small slug of fuel kicks off the pump nozzle.
When any of the vent lines are pinched by anything like the fuel tank,
kinks, plugged charcoal cannister, or non functioning liquid/vapor separator
the usual symptom is for the tank filler pipe to reverse flow a considerable
amount of fuel, often times spewing down the side of the coach, This usually
occurs when there is about 8 to 10 gallons left to fill. Unsafe to say the
least. Immediate solution is to fuel very slowly and listen at the filler
neck. When you hear the fuel coming up the pipe, stop the nozzle and wait
for it to go down into the tank. Big pain in the backside. Again the
solution is to make sure that the vent system is working as I have
described.
Hope this helps.
Jim Hupy
Salem, Or
1978 Royale

On Tue, Jun 15, 2010 at 2:22 PM, Bob de Kruyff <NEXT2POOL@aol.com> wrote:

>
>
> ""Regarding fuel cap blowing off. Should we be
> thinking about going to a venting fuel cap?
> Are our fuel pump trying to work against a
> huge vacuum???""
>
> Our caps are vented. They relieve at 1 to 1/2 psi pressure and also vent
> under a slight vacuum. I have seen many defective or incorrect ones.
>
>
>
> --
> Bob de Kruyff
> 78 Eleganza
> Chandler, AZ
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
_______________________________________________
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Re: [GMCnet] ????Vapor Lock (yes, again) [message #88723 is a reply to message #88718] Tue, 15 June 2010 17:28 Go to previous messageGo to next message
Bob de Kruyff   United States
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
Senior Member
I use Stant 11807

Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: [GMCnet] ????Vapor Lock (yes, again) [message #88726 is a reply to message #88722] Tue, 15 June 2010 17:33 Go to previous messageGo to next message
Ken Coit is currently offline  Ken Coit   United States
Messages: 151
Registered: November 2005
Karma: 0
Senior Member
I have no personal knowledge on this, but from
http://www.bdub.net/gmcfaq-body.html there is this:

The correct Stant gas cap for our vehicles is -Stant-11571 in locking and a
G 807 in non locking. The G807 may also be listed as a 10807 or 11807. but
don't worry about the difference in the first two digits as they are only
referencing the type of packaging the cap is in. For example I believe the
11807 is a blister pack and the 10807 is a cardboard pack. Also,
Napa-Balkamp #7031049. I have no experience with this cap; it may not be
locking.

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--
Ken Coit, ND7N
Raleigh, NC
Parfait Royale
1978 Royale Rear Bath, 403, 3.07
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Re: [GMCnet] ????Vapor Lock (yes, again) [message #88729 is a reply to message #88718] Tue, 15 June 2010 17:51 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
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Senior Member
10807 Stant

On Tue, Jun 15, 2010 at 3:04 PM, paul array <pumppal1@aol.com> wrote:
>
>
> Do you know the part number for the right cap?
>
> Paul A
> 73 Sequoia
> Key West, Florida
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--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] ????Vapor Lock (yes, again) [message #88753 is a reply to message #88729] Tue, 15 June 2010 20:07 Go to previous message
ldone is currently offline  ldone   United States
Messages: 34
Registered: November 2006
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Member
Jim B sells a insulated fuel line from the mechanical fuel pump to the carb. He said that is where the fuel heats the most.
I have one sitting on the toolbox waiting to be installed.


76PB
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