Home » Public Forums » GMCnet » [GMCnet] Vapor lock?
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| Re: [GMCnet] Vapor lock? [message #83978 is a reply to message #83962] |
Mon, 10 May 2010 19:23   |
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USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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Senior Member |
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Charles,
Last summer when Helen and I were driving from Houston over to New Orleans
it was 95° plus! I noted that whenever we would stop and the GMC would idle
for a minute or two the engine would stumble as we started under way again.
I attributed it to fuel being boiled out of the carb while we idled. I found
that as long as I accelerated slowly the influx of fresh gas would cool
everything down and in a few moments the engine would accelerate fine.
Don't know if you would call this vapor lock or not but it's why I removed
the intake manifold to plug the crossovers, found the cracked manifold, and
wound up installing an aluminum manifold.
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 Charles
Sent: Tuesday, 11 May 2010 8:51 AM
To: gmclist@temp.gmcnet.org
Subject: [GMCnet] Vapor lock?
How does one determine where the vapor lock is occurring?
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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
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| Re: [GMCnet] Vapor lock? [message #84008 is a reply to message #83962] |
Mon, 10 May 2010 21:43 |
fred v
Messages: 999
Registered: April 2006
Location: pensacola, fl.
Karma: 0
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i've had the same experience as Rob both before and after blocking the crossover. i turn on the electric fuel pump which usually solves the problem.
Fred V
'77 Royale RB 455
P'cola, Fl
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| Re: [GMCnet] Vapor lock? [message #84021 is a reply to message #84014] |
Mon, 10 May 2010 22:13 |
Charles
Messages: 455
Registered: January 2004
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I either had a definite vapor lock today or my new electric fuel
pump is going out. I drove the coach about 10 miles at 40 to
60 mile speeds. I stopped and dumped my holding tank. I
then drove around in a state park for about 10 minutes. Speed
never over 20 miles per hour in the park and engine temperature
never over 180 degrees. Then it happened. The coach died.
I tried to restart. No luck. Lifted the Eng. compartment lid. The
fuel filter was dry. Tried some more. Still no fuel in filter. I then
let it set for about 5 minutes. When I turned the key on the filter
filled with fuel I cranked the engine and started home. Still top
speed 30 miles per hour. Posted speed in the park is 20. Less
than 1/4 mile engine died again. I tried pouring water on all
exposed fuel lines. Still no fuel in filter. 45+ minutes later when
I turned the key on filter filled and engine started. Left the park
and went home. No more problems. Vapor lock or Fuel Pump?
Where does the vapor lock occur?In my case fuel could not be
pumped to the filter or carburetor. Fuel pump felt cold to my hand.
Charles
----- Original Message -----
From: "Rob Mueller" <robmueller@iinet.net.au>
To: <gmclist@temp.gmcnet.org>
Sent: Monday, May 10, 2010 10:00 PM
Subject: Re: [GMCnet] Vapor lock?
> Fred,
>
> So that tells me that the fuel IS boiling out of the carb bowl AND that
> changing to the aluminum manifold probably won't help!
>
> If it doesn't I think I'll get two of the thick gaskets that Dick Paterson
> sells with his rebuilt carbs to try and insulate the carb from the
> manifold
> more.
>
> 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 fred veenschoten
> Sent: Tuesday, 11 May 2010 12:44 PM
> To: gmclist@temp.gmcnet.org
> Subject: Re: [GMCnet] Vapor lock?
>
> i've had the same experience as Rob both before and after blocking the
> crossover. i turn on the electric fuel pump which usually solves the
> problem.
>
> --
> Fred V
> '77 Royale RB 455
> P'cola, Fl
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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Charles Wersal
Duncanville, Texas
26 foot 1975 Glenbrook
Pandora's Box
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| Re: [GMCnet] Vapor lock? [message #84030 is a reply to message #84021] |
Mon, 10 May 2010 23:34 |
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mike miller
Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon
Karma: 0
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| Charles wrote on Mon, 10 May 2010 20:13 |
... Vapor lock or Fuel Pump? Where does the vapor lock occur? ...
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Vapor lock is when the fuel on the suction side of the pump turns to vapor and the pump looses vacuum enough to "suck" liquid from the tank. Hot temperatures, long lines on the suction side of the pump and lower vapor pressure fuels all will contribute to the problem.
Most "modern" cars have the pump IN the tank to shorten the suction line as much as possible.
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] Vapor lock? [message #84031 is a reply to message #84030] |
Mon, 10 May 2010 23:48 |
Charles
Messages: 455
Registered: January 2004
Karma: 0
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Senior Member |
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Mike,
Thanks for the reply.
Do you know if anyone has tried to install an in tank
fuel pump to a GMC coach? My electric fuel pump
is right by the fuel selector valve. Makes me think, I
did not try switching tanks vacuum problems might
go away with tank switch. I also have been thinking
of adding a second pump. One to work off the wiring
for the primary tank and one to work off the wiring for
secondary tank. Switching tanks would switch pumps
and maybe eliminate vacuum problems. I had more
than 25 gallons of fuel in the tanks and had no
problem running my Onan while I was setting at the
side of the road waiting for the vapor lock to cool down
and go away.
Charles
----- Original Message -----
From: "Mike Miller" <m000035@gmail.com>
To: <gmclist@temp.gmcnet.org>
Sent: Monday, May 10, 2010 11:34 PM
Subject: Re: [GMCnet] Vapor lock?
>
>
> Charles wrote on Mon, 10 May 2010 20:13
>> ... Vapor lock or Fuel Pump? Where does the vapor lock occur? ...
>
>
> Vapor lock is when the fuel on the suction side of the pump turns to vapor
> and the pump looses vacuum enough to "suck" liquid from the tank. Hot
> temperatures, long lines on the suction side of the pump and lower vapor
> pressure fuels all will contribute to the problem.
>
> Most "modern" cars have the pump IN the tank to shorten the suction line
> as much as possible.
> --
> Mike Miller
> `73 26' X Painted D.
> `78 23' Birchaven
> Hillsboro, OR
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
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Charles Wersal
Duncanville, Texas
26 foot 1975 Glenbrook
Pandora's Box
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| Re: [GMCnet] Vapor lock? [message #84037 is a reply to message #84031] |
Tue, 11 May 2010 06:01 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
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Senior Member |
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Charles,
What I don't see is whether you could hear the electric pump running.
Pretty obvious symptom, but ...?
With those temperatures and the electric pump that near the tanks, you
should not have had a vapor lock problem.
You also didn't mention a filter ahead of the electric pump -- might it be
clogged already? Maybe the filter socks in the tanks? You can try blowing
them off with compressed air backward through the fuel supply lines -- AFTER
removing the fuel cap.
Ken H.
On Tue, May 11, 2010 at 12:48 AM, Charles <gcw13@sbcglobal.net> wrote:
> Mike,
> Thanks for the reply.
> Do you know if anyone has tried to install an in tank
> fuel pump to a GMC coach? My electric fuel pump
> is right by the fuel selector valve. Makes me think, I
> did not try switching tanks vacuum problems might
> go away with tank switch. I also have been thinking
> of adding a second pump. One to work off the wiring
> for the primary tank and one to work off the wiring for
> secondary tank. Switching tanks would switch pumps
> and maybe eliminate vacuum problems. I had more
> than 25 gallons of fuel in the tanks and had no
> problem running my Onan while I was setting at the
> side of the road waiting for the vapor lock to cool down
> and go away.
> Charles
> ----- Original Message -----
> From: "Mike Miller" <m000035@gmail.com>
> To: <gmclist@temp.gmcnet.org>
> Sent: Monday, May 10, 2010 11:34 PM
> Subject: Re: [GMCnet] Vapor lock?
>
>
> >
> >
> > Charles wrote on Mon, 10 May 2010 20:13
> >> ... Vapor lock or Fuel Pump? Where does the vapor lock occur? ...
> >
> >
> > Vapor lock is when the fuel on the suction side of the pump turns to
> vapor
> > and the pump looses vacuum enough to "suck" liquid from the tank. Hot
> > temperatures, long lines on the suction side of the pump and lower vapor
> > pressure fuels all will contribute to the problem.
> >
> > Most "modern" cars have the pump IN the tank to shorten the suction line
> > as much as possible.
> > --
> > Mike Miller
> > `73 26' X Painted D.
> > `78 23' Birchaven
> > Hillsboro, OR
> > _______________________________________________
> > 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
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
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| Re: [GMCnet] Vapor lock? [message #84046 is a reply to message #84037] |
Tue, 11 May 2010 07:45 |
Charles
Messages: 455
Registered: January 2004
Karma: 0
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Senior Member |
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Ken,
Thanks for the reply.
I don't suspect the socks but that might be. The fuel tanks
were cleaned and sealed in 2003. Secondary tank was
dropped in 2008 after the Santa Rosa Convention to
replace the fuel pump. Tank looked new inside at that time
and the old pump only had a bad sending unit. I'm not as
lucky as Roger Black. I don't have a Cochlear Implant. I can
no longer hear the fuel pump and I left the wife home on this
trip. I don't think it was pumping. Does it pump when it senses
pressure from a filled carburetor bowl? Would it have thought
a vapor lock was a full carburetor. It was not pumping while
I was putting water on everything. I felt of it at that time and
it was cool to the touch. That is one reason I kind of suspect
it might be the pump. I expected it to be warm from running,
not cool.Outside temperature was 96 degrees with bright sun
shine. Road surface was very hot on my back when I laid down
to water the fuel lines. Much hotter and I could have fried eggs.
I give up for now. Second fuel pump going on in the next few
days. This damn ethanol fuel is going to be my end.
Charles
----- Original Message -----
From: "Ken Henderson" <hend4800@bellsouth.net>
To: <gmclist@temp.gmcnet.org>
Sent: Tuesday, May 11, 2010 6:01 AM
Subject: Re: [GMCnet] Vapor lock?
> Charles,
>
> What I don't see is whether you could hear the electric pump running.
> Pretty obvious symptom, but ...?
>
> With those temperatures and the electric pump that near the tanks, you
> should not have had a vapor lock problem.
>
> You also didn't mention a filter ahead of the electric pump -- might it be
> clogged already? Maybe the filter socks in the tanks? You can try
> blowing
> them off with compressed air backward through the fuel supply lines --
> AFTER
> removing the fuel cap.
>
> Ken H.
>
>
> On Tue, May 11, 2010 at 12:48 AM, Charles <gcw13@sbcglobal.net> wrote:
>
>> Mike,
>> Thanks for the reply.
>> Do you know if anyone has tried to install an in tank
>> fuel pump to a GMC coach? My electric fuel pump
>> is right by the fuel selector valve. Makes me think, I
>> did not try switching tanks vacuum problems might
>> go away with tank switch. I also have been thinking
>> of adding a second pump. One to work off the wiring
>> for the primary tank and one to work off the wiring for
>> secondary tank. Switching tanks would switch pumps
>> and maybe eliminate vacuum problems. I had more
>> than 25 gallons of fuel in the tanks and had no
>> problem running my Onan while I was setting at the
>> side of the road waiting for the vapor lock to cool down
>> and go away.
>> Charles
>> ----- Original Message -----
>> From: "Mike Miller" <m000035@gmail.com>
>> To: <gmclist@temp.gmcnet.org>
>> Sent: Monday, May 10, 2010 11:34 PM
>> Subject: Re: [GMCnet] Vapor lock?
>>
>>
>> >
>> >
>> > Charles wrote on Mon, 10 May 2010 20:13
>> >> ... Vapor lock or Fuel Pump? Where does the vapor lock occur? ...
>> >
>> >
>> > Vapor lock is when the fuel on the suction side of the pump turns to
>> vapor
>> > and the pump looses vacuum enough to "suck" liquid from the tank. Hot
>> > temperatures, long lines on the suction side of the pump and lower
>> > vapor
>> > pressure fuels all will contribute to the problem.
>> >
>> > Most "modern" cars have the pump IN the tank to shorten the suction
>> > line
>> > as much as possible.
>> > --
>> > Mike Miller
>> > `73 26' X Painted D.
>> > `78 23' Birchaven
>> > Hillsboro, OR
>> > _______________________________________________
>> > 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
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
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Charles Wersal
Duncanville, Texas
26 foot 1975 Glenbrook
Pandora's Box
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| Re: [GMCnet] Vapor lock? [message #84070 is a reply to message #83962] |
Tue, 11 May 2010 10:48 |
fred v
Messages: 999
Registered: April 2006
Location: pensacola, fl.
Karma: 0
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Senior Member |
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sure sounds like a pump problem. mine started flooding the carb. i checked it and it was putting out 20 PSI. they can act up. the pump is supposed to sense the float valve closing and the build up of pressure in the line. this is what shuts it off. with vapor lock the pump should put out enough pressure to overcome the vapor lock.
if you are running the electric pump all the time then you would not experience vapor lock as there is no suction action between the tank and carb to create it.
Fred V
'77 Royale RB 455
P'cola, Fl
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| Re: [GMCnet] Vapor lock? [message #84076 is a reply to message #84070] |
Tue, 11 May 2010 11:56 |
Ken Coit
Messages: 151
Registered: November 2005
Karma: 0
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The Carter P4070 runs continuously unless you have a manual switch to
control it. I doubt it is ever cold to the touch while running. The
mechanical pump (do you have one?) might be able to pull fuel through the
Carter, but a check valve bypass is recommended. Maybe you also have a
collapsing line between the pumps which is fine so long as the electric pump
is pushing?
On Tue, May 11, 2010 at 11:48 AM, fred veenschoten <fredntoni@cox.net>wrote:
>
>
> sure sounds like a pump problem. mine started flooding the carb. i checked
> it and it was putting out 20 PSI. they can act up. the pump is supposed to
> sense the float valve closing and the build up of pressure in the line. this
> is what shuts it off. with vapor lock the pump should put out enough
> pressure to overcome the vapor lock.
>
> if you are running the electric pump all the time then you would not
> experience vapor lock as there is no suction action between the tank and
> carb to create it.
>
> --
> Fred V
> '77 Royale RB 455
> P'cola, Fl
> _______________________________________________
> GMCnet mailing list
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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? [message #84094 is a reply to message #84076] |
Tue, 11 May 2010 14:32 |
Charles
Messages: 455
Registered: January 2004
Karma: 0
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Senior Member |
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I have been running Facet/Purolator electric fuel pumps
since 2002. Have had several problems through the years.
Except for one time, I have not been able to distinguish
between pump problems and vapor lock. This morning
I removed the pump that was on the coach yesterday and
installed another. I contacted Facet/Puralator and discussed
the problems I have been having. Both an engineer and the
sales manager doubted vapor lock or fuel pump. They felt
it was probably vacuum in my fuel tank due to poor venting.
This is a good possibility as just last week I had fuel leaking
out of the "T" fitting where the two vent lines coming off the
tanks join together. I guess I'm going back on the road with
a different fuel pump and the old as a spare. If I keep having
these problems I will be going to two fuel pump system. Several
have mentioned the manual pump. I removed it in February 2009.
I now rely solely on the electric pump. Thanks to all for their
responses to my inquiry. Good by for now. Until it happens again.
Charles
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Charles Wersal
Duncanville, Texas
26 foot 1975 Glenbrook
Pandora's Box
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| Re: [GMCnet] Vapor lock? [message #84132 is a reply to message #83978] |
Tue, 11 May 2010 19:30 |
George Ciz
Messages: 2
Registered: May 2009
Karma: 0
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Junior Member |
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It happened to me on way to Pueblo last year as I was approaching Phoenix.
I am using an electric fuel pump with TBI. Only fix was stop and let cool
down. Half way to Flagstaff out of Phoenix, outside temperature cooled
enough that the 78 Eleganza roared into town. Very long and frustrating day
from El Toro CA to Flagstaff.
On Mon, May 10, 2010 at 5:23 PM, Rob Mueller <robmueller@iinet.net.au>wrote:
> Charles,
>
> Last summer when Helen and I were driving from Houston over to New Orleans
> it was 95° plus! I noted that whenever we would stop and the GMC would idle
> for a minute or two the engine would stumble as we started under way again.
>
> I attributed it to fuel being boiled out of the carb while we idled. I
> found
> that as long as I accelerated slowly the influx of fresh gas would cool
> everything down and in a few moments the engine would accelerate fine.
>
> Don't know if you would call this vapor lock or not but it's why I removed
> the intake manifold to plug the crossovers, found the cracked manifold, and
> wound up installing an aluminum manifold.
>
> 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 Charles
> Sent: Tuesday, 11 May 2010 8:51 AM
> To: gmclist@temp.gmcnet.org
> Subject: [GMCnet] Vapor lock?
>
> How does one determine where the vapor lock is occurring?
> _______________________________________________
> 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
>
_______________________________________________
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List Information and Subscription Options:
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| Re: [GMCnet] Vapor lock? [message #84167 is a reply to message #84132] |
Wed, 12 May 2010 05:30 |
Steven Ferguson
Messages: 3447
Registered: May 2006
Karma: 0
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Senior Member |
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George,
Another way to beat that is not fill the tank completely up and stop
more frequently to dump cooler fuel on top of the stuff that's boilng
in the tank. It's the only thing that helped me make it from Yuma to
Tucson in 100 deg temps last year. The stuff coming out of the pumps
wasn't all that cool but it did the trick.
On Tue, May 11, 2010 at 5:30 PM, George Ciz <cizgeo@gmail.com> wrote:
> It happened to me on way to Pueblo last year as I was approaching Phoenix.
> I am using an electric fuel pump with TBI. Only fix was stop and let cool
> down. Half way to Flagstaff out of Phoenix, outside temperature cooled
> enough that the 78 Eleganza roared into town. Very long and frustrating day
> from El Toro CA to Flagstaff.
>
> On Mon, May 10, 2010 at 5:23 PM, Rob Mueller <robmueller@iinet.net.au>wrote:
>
>> Charles,
>>
>> Last summer when Helen and I were driving from Houston over to New Orleans
>> it was 95° plus! I noted that whenever we would stop and the GMC would idle
>> for a minute or two the engine would stumble as we started under way again.
>>
>> I attributed it to fuel being boiled out of the carb while we idled. I
>> found
>> that as long as I accelerated slowly the influx of fresh gas would cool
>> everything down and in a few moments the engine would accelerate fine.
>>
>> Don't know if you would call this vapor lock or not but it's why I removed
>> the intake manifold to plug the crossovers, found the cracked manifold, and
>> wound up installing an aluminum manifold.
>>
>> 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 Charles
>> Sent: Tuesday, 11 May 2010 8:51 AM
>> To: gmclist@temp.gmcnet.org
>> Subject: [GMCnet] Vapor lock?
>>
>> How does one determine where the vapor lock is occurring?
>> _______________________________________________
>> 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
>
--
Steve Ferguson
'76 EII
Sierra Vista, AZ
Urethane bushing source
www.bdub.net/ferguson/
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| Re: [GMCnet] Vapor lock? [message #84173 is a reply to message #83962] |
Wed, 12 May 2010 07:05 |
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I experienced vapor lock on a regular basis when the roadway was hot, almost always after stopping for a traffic light. I installed exhaust heat shields to shield the hot exhaust pipe from the fuel tanks and a full "belly pan" heat shield below the tanks and these reduced the frequency of vapor lock but did not completely eliminate it.
The "fix" I did to eliminate the effect was to install an electric fuel pump in the back by the tanks controlled by the fuel selector switch. As soon as I sense a hesitation I switch to the auxiliary tank which turns on the electric pump. Once I'm back to cruising down the road I switch back to the main tank which turns off the electric pump and I'm golden.
Bill Brown - '77 Buckeye Cruiser
Coshocton OH
carguybill@sbcglobal.net
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| Re: [GMCnet] Vapor lock? [message #84185 is a reply to message #84173] |
Wed, 12 May 2010 08:19 |
Steven Ferguson
Messages: 3447
Registered: May 2006
Karma: 0
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Senior Member |
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Bill,
That tarmack gets very hot. I shot it once with my temp gun and on a
90 deg sunny day, the temp was 140 deg. The new fuels boil at as low
as 85 deg at some elevation. Howard Neilson did as you, made a belly
shield between the tanks and the road surface, he also added a cross
babble to shield the tanks from eng comp and exhaust plumbing heat.
He has reported no problems since.
Jim Anstett glued ceramic paper to the downsides of his tanks.
On Wed, May 12, 2010 at 5:05 AM, Bill Brown <carguybill@sbcglobal.net> wrote:
>
>
> I experienced vapor lock on a regular basis when the roadway was hot, almost always after stopping for a traffic light. I installed exhaust heat shields to shield the hot exhaust pipe from the fuel tanks and a full "belly pan" heat shield below the tanks and these reduced the frequency of vapor lock but did not completely eliminate it.
>
> The "fix" I did to eliminate the effect was to install an electric fuel pump in the back by the tanks controlled by the fuel selector switch. As soon as I sense a hesitation I switch to the auxiliary tank which turns on the electric pump. Once I'm back to cruising down the road I switch back to the main tank which turns off the electric pump and I'm golden.
> --
> Bill Brown - '77 Buckeye Cruiser
> Coshocton OH
> carguybill@sbcglobal.net
> _______________________________________________
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>
--
Steve Ferguson
'76 EII
Sierra Vista, AZ
Urethane bushing source
www.bdub.net/ferguson/
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