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Fuel Pump or Carburetor?

JK
Jim Kanomata
Tue, Jul 27, 2021 6:35 PM

Eric, I was young once and leaned from tons of older guys and asked lot of
questions and had them saying that for an Engineer your wanting to learn,
not like the rest.
Feel free to call me with any questions.

On Tue, Jul 27, 2021 at 10:22 AM Eric Roell ericwr@rogers.com wrote:

Hello Jim,Thanks for the detailed response and suggestions, all very
valuable and noted.Although I am younger than most GMC owners, I did grow
up in the seventies with the anguish of older carbureted motorcycles, boats
and of course V8 cars, I still own a 73 Mustang and an older carbureted V8
boat.I will start working on the coach next month to get it road worthy and
make a few small trips around town to establish my priority ($$$) list.
EFI does sound intriging to me.
Eric Roell, Aurora, Ontario76 Glenbrook "Safari" 76,000 miles,Alcoa,
Continental Kit, Fender Flares, Stainless Exhaust, Macerator, Ragusa Step

 On Tuesday, July 27, 2021, 10:09:43 a.m. EDT, James Hupy <

jamesh1296@gmail.com> wrote:

One of the weaknesses of the quadrajet Carburetor is the fact that it has
a
small internal reservoir of fuel, and is subject to heat soak on the
motorhome because of the lowered placement of the carb to allow for hood
clearance. This places the carb base very close to the exhaust crossover
passage in the manifold. Result being that the small fuel reserve in the
float bowl evaporates, leaving no fuel in the carb to start the engine.
Fix? Three ways that I know work are,  an auxiliary electric fuel pump in
the supply fuel line, that can be run before starting the engine to fill
the float bowl, and/or blocking off the crossover passages to reduce
heating of the Carburetor, and third, convert the coach to fuel injection.
That gets rid of the Carburetor, mechanical fuel pump, etc. $$$$ but
effective, and perhaps a good choice for younger drivers who can't seem to
grasp all the "oddities" of 40+ year old engines.
Jim Hupy
Salem, Oregon

On Tue, Jul 27, 2021, 6:41 AM John R. Lebetski gransport7087@gmail.com
wrote:

Part of it may be operator error.  Starting a 70s carbureted vehicle
is completely different  process than starting a newer computer
controlled vehicle.  Procedures are in owners manual to read for cold and
hot starts.
If it has been sitting a long long time, carb should fill and engine
start under 10 seconds on a stock setup if everything is correct. .
You may have a combination of issues

  1. leaking carb bowl well plugs
  2. weak accelerator pump in carb
  3. gummed or misadjusted choke
  4. incorrect starting procedure.
    --
    John Lebetski
    Woodstock, IL
    77 Eleganza II

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

Eric, I was young once and leaned from tons of older guys and asked lot of questions and had them saying that for an Engineer your wanting to learn, not like the rest. Feel free to call me with any questions. On Tue, Jul 27, 2021 at 10:22 AM Eric Roell <ericwr@rogers.com> wrote: > Hello Jim,Thanks for the detailed response and suggestions, all very > valuable and noted.Although I am younger than most GMC owners, I did grow > up in the seventies with the anguish of older carbureted motorcycles, boats > and of course V8 cars, I still own a 73 Mustang and an older carbureted V8 > boat.I will start working on the coach next month to get it road worthy and > make a few small trips around town to establish my priority ($$$) list. > EFI does sound intriging to me. > Eric Roell, Aurora, Ontario76 Glenbrook "Safari" 76,000 miles,Alcoa, > Continental Kit, Fender Flares, Stainless Exhaust, Macerator, Ragusa Step > > On Tuesday, July 27, 2021, 10:09:43 a.m. EDT, James Hupy < > jamesh1296@gmail.com> wrote: > > One of the weaknesses of the quadrajet Carburetor is the fact that it has > a > small internal reservoir of fuel, and is subject to heat soak on the > motorhome because of the lowered placement of the carb to allow for hood > clearance. This places the carb base very close to the exhaust crossover > passage in the manifold. Result being that the small fuel reserve in the > float bowl evaporates, leaving no fuel in the carb to start the engine. > Fix? Three ways that I know work are, an auxiliary electric fuel pump in > the supply fuel line, that can be run before starting the engine to fill > the float bowl, and/or blocking off the crossover passages to reduce > heating of the Carburetor, and third, convert the coach to fuel injection. > That gets rid of the Carburetor, mechanical fuel pump, etc. $$$$ but > effective, and perhaps a good choice for younger drivers who can't seem to > grasp all the "oddities" of 40+ year old engines. > Jim Hupy > Salem, Oregon > > On Tue, Jul 27, 2021, 6:41 AM John R. Lebetski <gransport7087@gmail.com> > wrote: > > > Part of it may be operator error. Starting a 70s carbureted vehicle > > is completely different process than starting a newer computer > > controlled vehicle. Procedures are in owners manual to read for cold and > > hot starts. > > If it has been sitting a long long time, carb should fill and engine > > start under 10 seconds on a stock setup if everything is correct. . > > You may have a combination of issues > > 1) leaking carb bowl well plugs > > 2) weak accelerator pump in carb > > 3) gummed or misadjusted choke > > 4) incorrect starting procedure. > > -- > > John Lebetski > > Woodstock, IL > > 77 Eleganza II > > _______________________________________________ > > GMCnet mailing list > > Unsubscribe or Change List Options: > > > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options: > > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options: > -- Jim Kanomata ASE Applied/GMC, Newark,CA jimk@appliedairfilters.com http://www.gmcrvparts.com 1-800-752-7502
ER
Eric Roell
Tue, Jul 27, 2021 7:01 PM

I appreciate the offer Jim.  Once I delve in the coach further, I will know more about the problems I am dealing with.
Eric Roell, Aurora, Ontario76 Glenbrook "Safari" 76,000 miles,Alcoa, Continental Kit, Fender Flares, Stainless Exhaust, Macerator, Ragusa Step

On Tuesday, July 27, 2021, 02:36:18 p.m. EDT, Jim Kanomata <jimkanomata@gmail.com> wrote:  

Eric, I was young once and leaned from tons of older guys and asked lot of
questions and had them saying that for an Engineer your wanting to learn,
not like the rest.
Feel free to call me with any questions.

On Tue, Jul 27, 2021 at 10:22 AM Eric Roell ericwr@rogers.com wrote:

Hello Jim, Thanks for the detailed response and suggestions, all very
valuable and noted. Although I am younger than most GMC owners, I did grow
up in the seventies with the anguish of older carbureted motorcycles, boats
and of course V8 cars, I still own a 73 Mustang and an older carbureted V8
boat. I will start working on the coach next month to get it road worthy and
make a few small trips around town to establish my priority ($$$) list.
EFI does sound intriging to me.
Eric Roell, Aurora, Ontario76 Glenbrook "Safari" 76,000 miles, Alcoa,
Continental Kit, Fender Flares, Stainless Exhaust, Macerator, Ragusa Step

    On Tuesday, July 27, 2021, 10:09:43 a.m. EDT, James Hupy <
jamesh1296@gmail.com> wrote:

  One of the weaknesses of the quadrajet Carburetor is the fact that it has
a
small internal reservoir of fuel, and is subject to heat soak on the
motorhome because of the lowered placement of the carb to allow for hood
clearance. This places the carb base very close to the exhaust crossover
passage in the manifold. Result being that the small fuel reserve in the
float bowl evaporates, leaving no fuel in the carb to start the engine.
Fix? Three ways that I know work are,  an auxiliary electric fuel pump in
the supply fuel line, that can be run before starting the engine to fill
the float bowl, and/or blocking off the crossover passages to reduce
heating of the Carburetor, and third, convert the coach to fuel injection.
That gets rid of the Carburetor, mechanical fuel pump, etc. $$$$ but
effective, and perhaps a good choice for younger drivers who can't seem to
grasp all the "oddities" of 40+ year old engines.
Jim Hupy
Salem, Oregon

On Tue, Jul 27, 2021, 6:41 AM John R. Lebetski gransport7087@gmail.com
wrote:

Part of it may be operator error.  Starting a 70s carbureted vehicle
  is completely different  process than starting a newer computer
controlled vehicle.  Procedures are in owners manual to read for cold and
hot starts.
  If it has been sitting a long long time, carb should fill and engine
start under 10 seconds on a stock setup if everything is correct. .
You may have a combination of issues

  1. leaking carb bowl well plugs
  2. weak accelerator pump in carb
  3. gummed or misadjusted choke
  4. incorrect starting procedure.
    --
    John Lebetski
    Woodstock, IL
    77 Eleganza II

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GMCnet mailing list
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--
Jim Kanomata ASE
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.com
1-800-752-7502


GMCnet mailing list
Unsubscribe or Change List Options:

I appreciate the offer Jim.  Once I delve in the coach further, I will know more about the problems I am dealing with. Eric Roell, Aurora, Ontario76 Glenbrook "Safari" 76,000 miles,Alcoa, Continental Kit, Fender Flares, Stainless Exhaust, Macerator, Ragusa Step On Tuesday, July 27, 2021, 02:36:18 p.m. EDT, Jim Kanomata <jimkanomata@gmail.com> wrote: Eric, I was young once and leaned from tons of older guys and asked lot of questions and had them saying that for an Engineer your wanting to learn, not like the rest. Feel free to call me with any questions. On Tue, Jul 27, 2021 at 10:22 AM Eric Roell <ericwr@rogers.com> wrote: > Hello Jim, Thanks for the detailed response and suggestions, all very > valuable and noted. Although I am younger than most GMC owners, I did grow > up in the seventies with the anguish of older carbureted motorcycles, boats > and of course V8 cars, I still own a 73 Mustang and an older carbureted V8 > boat. I will start working on the coach next month to get it road worthy and > make a few small trips around town to establish my priority ($$$) list. > EFI does sound intriging to me. > Eric Roell, Aurora, Ontario76 Glenbrook "Safari" 76,000 miles, Alcoa, > Continental Kit, Fender Flares, Stainless Exhaust, Macerator, Ragusa Step > >    On Tuesday, July 27, 2021, 10:09:43 a.m. EDT, James Hupy < > jamesh1296@gmail.com> wrote: > >  One of the weaknesses of the quadrajet Carburetor is the fact that it has > a > small internal reservoir of fuel, and is subject to heat soak on the > motorhome because of the lowered placement of the carb to allow for hood > clearance. This places the carb base very close to the exhaust crossover > passage in the manifold. Result being that the small fuel reserve in the > float bowl evaporates, leaving no fuel in the carb to start the engine. > Fix? Three ways that I know work are,  an auxiliary electric fuel pump in > the supply fuel line, that can be run before starting the engine to fill > the float bowl, and/or blocking off the crossover passages to reduce > heating of the Carburetor, and third, convert the coach to fuel injection. > That gets rid of the Carburetor, mechanical fuel pump, etc. $$$$ but > effective, and perhaps a good choice for younger drivers who can't seem to > grasp all the "oddities" of 40+ year old engines. > Jim Hupy > Salem, Oregon > > On Tue, Jul 27, 2021, 6:41 AM John R. Lebetski <gransport7087@gmail.com> > wrote: > > > Part of it may be operator error.  Starting a 70s carbureted vehicle > >  is completely different  process than starting a newer computer > > controlled vehicle.  Procedures are in owners manual to read for cold and > > hot starts. > >  If it has been sitting a long long time, carb should fill and engine > > start under 10 seconds on a stock setup if everything is correct. . > > You may have a combination of issues > > 1) leaking carb bowl well plugs > > 2) weak accelerator pump in carb > > 3) gummed or misadjusted choke > > 4) incorrect starting procedure. > > -- > > John Lebetski > > Woodstock, IL > > 77 Eleganza II > > _______________________________________________ > > GMCnet mailing list > > Unsubscribe or Change List Options: > > > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options: > > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options: > -- Jim Kanomata ASE Applied/GMC, Newark,CA jimk@appliedairfilters.com http://www.gmcrvparts.com 1-800-752-7502 _______________________________________________ GMCnet mailing list Unsubscribe or Change List Options:
DS
Douglas Smith
Tue, Jul 27, 2021 7:44 PM

Thank you for the reminder Larry. I do turn it over a bit before hitting the prime switch.

Douglas & Virginia Smith,
dsmithy18 at gmail,
Lincoln Nebraska,
’73 “Sequoia” since ‘95: "Wanabizo";
Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels/Sundry other

Thank you for the reminder Larry. I do turn it over a bit before hitting the prime switch. -- Douglas & Virginia Smith, dsmithy18 at gmail, Lincoln Nebraska, ’73 “Sequoia” since ‘95: "Wanabizo"; Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels/Sundry other
DL
delbert lecky
Thu, Jul 29, 2021 1:42 AM

Had my carb rebuilt by Canadian carb in bc and my ignition by Patterson's in Ontario. Both smart upgrades. Electric fuel pump on the secondary tank. Also block offs on the intake and manual choke. Works great.

Sent from Yahoo Mail on Android

On Tue., 27 Jul. 2021 at 12:44 p.m., Douglas Smithdsmithy18@gmail.com wrote:  Thank you for the reminder Larry. I do turn it over a bit before hitting the prime switch.

Douglas & Virginia Smith,
dsmithy18 at gmail,
Lincoln Nebraska,
’73 “Sequoia” since ‘95: "Wanabizo";
Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels/Sundry other


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Unsubscribe or Change List Options:

Had my carb rebuilt by Canadian carb in bc and my ignition by Patterson's in Ontario. Both smart upgrades. Electric fuel pump on the secondary tank. Also block offs on the intake and manual choke. Works great. Sent from Yahoo Mail on Android On Tue., 27 Jul. 2021 at 12:44 p.m., Douglas Smith<dsmithy18@gmail.com> wrote: Thank you for the reminder Larry. I do turn it over a bit before hitting the prime switch. -- Douglas & Virginia Smith, dsmithy18 at gmail, Lincoln Nebraska, ’73 “Sequoia” since ‘95: "Wanabizo"; Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels/Sundry other _______________________________________________ GMCnet mailing list Unsubscribe or Change List Options:
ER
Eric Roell
Fri, Jul 30, 2021 3:35 PM

Great feedback, thank you.PS - nice to have some Canadian content!
Eric Roell, Aurora, Ontario76 Glenbrook "Safari" 76,000 miles,Alcoa, Continental Kit, Fender Flares, Stainless Exhaust, Macerator, Ragusa Step

On Wednesday, July 28, 2021, 09:42:50 p.m. EDT, delbert lecky via Gmclist <gmclist@list.gmcnet.org> wrote:  

Had my carb rebuilt by Canadian carb in bc and my ignition by Patterson's in Ontario. Both smart upgrades. Electric fuel pump on the secondary tank. Also block offs on the intake and manual choke. Works great.

Sent from Yahoo Mail on Android

  On Tue., 27 Jul. 2021 at 12:44 p.m., Douglas Smithdsmithy18@gmail.com wrote:  Thank you for the reminder Larry. I do turn it over a bit before hitting the prime switch.

Douglas & Virginia Smith,
dsmithy18 at gmail,
Lincoln Nebraska,
’73 “Sequoia” since ‘95: "Wanabizo";
Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels/Sundry other


GMCnet mailing list
Unsubscribe or Change List Options:
 


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Unsubscribe or Change List Options:

Great feedback, thank you.PS - nice to have some Canadian content! Eric Roell, Aurora, Ontario76 Glenbrook "Safari" 76,000 miles,Alcoa, Continental Kit, Fender Flares, Stainless Exhaust, Macerator, Ragusa Step On Wednesday, July 28, 2021, 09:42:50 p.m. EDT, delbert lecky via Gmclist <gmclist@list.gmcnet.org> wrote: Had my carb rebuilt by Canadian carb in bc and my ignition by Patterson's in Ontario. Both smart upgrades. Electric fuel pump on the secondary tank. Also block offs on the intake and manual choke. Works great. Sent from Yahoo Mail on Android   On Tue., 27 Jul. 2021 at 12:44 p.m., Douglas Smith<dsmithy18@gmail.com> wrote:  Thank you for the reminder Larry. I do turn it over a bit before hitting the prime switch. -- Douglas & Virginia Smith, dsmithy18 at gmail, Lincoln Nebraska, ’73 “Sequoia” since ‘95: "Wanabizo"; Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels/Sundry other _______________________________________________ GMCnet mailing list Unsubscribe or Change List Options:   _______________________________________________ GMCnet mailing list Unsubscribe or Change List Options: