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In tank fuel pump question [message #354021] Wed, 22 April 2020 17:40 Go to next message
Ken M is currently offline  Ken M   United States
Messages: 32
Registered: December 2019
Location: Redding, CA
Karma: 0
Member
I will begin the process of fixing fuel delivery issues on my motorhome. The previous owner (my Grandpa!) let it sit for a bit too long. It has trouble getting fuel from the tanks all the way to the carb. It will start and run just fine on a small tank strapped to the bumper. So I want to drop the fuel tanks, verify they are clean, and begin to replace everything that might need replacing due to age and ethanol. I will likely run with the carburetor for a few years before possibly looking at fuel injection - that said - I'd like to make life as easy as possible on myself once this is done. I live in Northern California, where it gets very hot in the summer (well above 100). I want to minimize vapor lock as much as possible with the carb setup, so I will be looking to:
1. Potentially rebuild carb
2. Insulated carb to fuel pump line
3. New Gates Barricade fuel lines all the way around
4. Polyarmor hard lines at least on top of the tanks
5. New fuel tank selector valve
6. New manual fuel pump
7. New in tank electric fuel pumps - https://www.gmcrvparts.com/product-p/gm12-007.3.htm
8. Access holes in floor to facilitate electric pump service in the future.

Has anyone used the above in tank fuel pumps? They seem like the easiest, quickest, and maybe best path forward? Any other advice, or parts/pieces I might be missing?

Thanks,
Ken


1975 - 26’ Eleganza II Unsure of what upgrades may have been done. I'm working on sorting that out in the coming months. Ken Morefield - Redding, CA
Re: In tank fuel pump question [message #354023 is a reply to message #354021] Wed, 22 April 2020 18:48 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
Ken,

I am going to address your issues inline for two reasons (even though I don't like doing this):
A - It should be clearer in the final reading.
B - I am a little lazy about some things....

Ken M wrote on Wed, 22 April 2020 18:40

I will begin the process of fixing fuel delivery issues on my motorhome. The previous owner (my Grandpa!) let it sit for a bit too long. It has trouble getting fuel from the tanks all the way to the carb.
**Given the age and condition of the coach, I would bet that the rubber lines on top of the tank have become porous.**
It will start and run just fine on a small tank strapped to the bumper. So I want to drop the fuel tanks, verify they are clean, and begin to replace everything that might need replacing due to age and ethanol.
**This is not a terrible job (wrote the guy that had his tanks down 5 times until he got it right). I will send you my notes on methods and what I have learned if you would like. (That is really just me hoping to save someone else four tank services.)
I will likely run with the carburetor for a few years before possibly looking at fuel injection - that said - I'd like to make life as easy as possible on myself once this is done. I live in Northern California, where it gets very hot in the summer (well above 100). I want to minimize vapor lock as much as possible with the carb setup, so I will be looking to:
1. Potentially rebuild carb
**The word rebuild is over used here. Just buy a kit, read the instructions on the Rochester site, clean it and put it back on. GENTLY
**Ask us before trying to remove it. The filter plug is easily damaged and expensive to repair.
2. Insulated carb to fuel pump line
**This is the one line that is under pressure and does not really need insulation. OR at lease it didn't help me much.
3. New Gates Barricade fuel lines all the way around
**Very good plan - It has been good for me.
4. Polyarmor hard lines at least on top of the tanks
**Also a good plan that was kind of a pain but I don't have to worry about the rubber on top of the tanks again.
5. New fuel tank selector valve
**What you have is probably junk, most are but the replacement is upside down and backwards and take some creativity to install.
6. New manual fuel pump
**Do not do this if you are going to in-tank pumps or any electric pumps *** More down the page
7. New in tank electric fuel pumps - https://www.gmcrvparts.com/product-p/gm12-007.3.htm
**If going to TBI this is a good idea. More down the page - again
8. Access holes in floor to facilitate electric pump service in the future.
**This can't hurt.

Has anyone used the above in tank fuel pumps? They seem like the easiest, quickest, and maybe best path forward? Any other advice, or parts/pieces I might be missing?

Thanks,
Ken
****************
Getting away from the engine driven pump is not all bad, but many have had success with low pressure (for carburetor) pumps mounted low in the frame where there is very little lift height (negative pressure) to deal with and they are easily serviced.
If you mount a pump for each tank, you can eliminate the selector valve with a little additional control and then have built in redundancy. If you later go to TBI, the pumps will want to be in the tank for cooling.

When you arrived here back in January I warned you that we all have this agenda that is to see to it that you get to enjoy your coach and what it can do for you. All you have to do is ask and you will get the benefit of a truly awesome amount of experience. (I, by the way, am a piker in this crowd.)

Please keep us apprised of your plans and ask us before you spend money.
When JimK said call him, he meant it. He knows about these things and knows what the good parts are.

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] In tank fuel pump question [message #354024 is a reply to message #354023] Wed, 22 April 2020 18:55 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
If your reluctant to call me for advise, your wasting your time in many
cases. Should I feel I cannot assist them, I usually refer them to others
that I feel is more capable.
There are areas of the coach I do not like to dabble in , so I let Nick or
others handle it.

On Wed, Apr 22, 2020 at 4:49 PM Matt Colie via Gmclist <
gmclist@list.gmcnet.org> wrote:

> Ken,
>
> I am going to address your issues inline for two reasons (even though I
> don't like doing this):
> A - It should be clearer in the final reading.
> B - I am a little lazy about some things....
>
> Ken M wrote on Wed, 22 April 2020 18:40
>> I will begin the process of fixing fuel delivery issues on my
> motorhome. The previous owner (my Grandpa!) let it sit for a bit too
> long. It has
>> trouble getting fuel from the tanks all the way to the carb.
>> **Given the age and condition of the coach, I would bet that the rubber
> lines on top of the tank have become porous.**
>> It will start and run just fine on a small tank strapped to the bumper.
> So I want to drop the fuel tanks, verify they are clean, and begin to
>> replace everything that might need replacing due to age and ethanol.
>> **This is not a terrible job (wrote the guy that had his tanks down 5
> times until he got it right). I will send you my notes on methods and what
>> I have learned if you would like. (That is really just me hoping to
> save someone else four tank services.)
>> I will likely run with the carburetor for a few years before possibly
> looking at fuel injection - that said - I'd like to make life as easy as
>> possible on myself once this is done. I live in Northern California,
> where it gets very hot in the summer (well above 100). I want to minimize
>> vapor lock as much as possible with the carb setup, so I will be looking
> to:
>> 1. Potentially rebuild carb
>> **The word rebuild is over used here. Just buy a kit, read the
> instructions on the Rochester site, clean it and put it back on. GENTLY
>> **Ask us before trying to remove it. The filter plug is easily damaged
> and expensive to repair.
>> 2. Insulated carb to fuel pump line
>> **This is the one line that is under pressure and does not really need
> insulation. OR at lease it didn't help me much.
>> 3. New Gates Barricade fuel lines all the way around
>> **Very good plan - It has been good for me.
>> 4. Polyarmor hard lines at least on top of the tanks
>> **Also a good plan that was kind of a pain but I don't have to worry
> about the rubber on top of the tanks again.
>> 5. New fuel tank selector valve
>> **What you have is probably junk, most are but the replacement is upside
> down and backwards and take some creativity to install.
>> 6. New manual fuel pump
>> **Do not do this if you are going to in-tank pumps or any electric pumps
> *** More down the page
>> 7. New in tank electric fuel pumps -
> https://www.gmcrvparts.com/product-p/gm12-007.3.htm
>> **If going to TBI this is a good idea. More down the page - again
>> 8. Access holes in floor to facilitate electric pump service in the
> future.
>> **This can't hurt.
>>
>> Has anyone used the above in tank fuel pumps? They seem like the
> easiest, quickest, and maybe best path forward? Any other advice, or
>> parts/pieces I might be missing?
>>
>> Thanks,
>> Ken
>
> ****************
> Getting away from the engine driven pump is not all bad, but many have had
> success with low pressure (for carburetor) pumps mounted low in the frame
> where there is very little lift height (negative pressure) to deal with
> and they are easily serviced.
> If you mount a pump for each tank, you can eliminate the selector valve
> with a little additional control and then have built in redundancy. If you
> later go to TBI, the pumps will want to be in the tank for cooling.
>
> When you arrived here back in January I warned you that we all have this
> agenda that is to see to it that you get to enjoy your coach and what it can
> do for you. All you have to do is ask and you will get the benefit of a
> truly awesome amount of experience. (I, by the way, am a piker in this
> crowd.)
>
> Please keep us apprised of your plans and ask us before you spend money.
> When JimK said call him, he meant it. He knows about these things and
> knows what the good parts are.
>
> Matt
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.gmcrvparts.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: In tank fuel pump question [message #354032 is a reply to message #354021] Thu, 23 April 2020 07:26 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada
Karma: 3
Senior Member
For in-tank pumps, if you stay with the carb you will need low pressure pumps. Then when you change to EFI, you will need to change the pumps to high pressure units. So you might want to save the $250 for low pressure pumps and goto EFI now.

just saying.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: [GMCnet] In tank fuel pump question [message #354033 is a reply to message #354032] Thu, 23 April 2020 07:58 Go to previous messageGo to next message
Billy Massey is currently offline  Billy Massey   United States
Messages: 916
Registered: January 2004
Location: Central Texas
Karma: 1
Senior Member

Sounds like my wife.
Spend $1k to save $250. ;-)

Naw, I know what your talkin about. Just had to comment. Gave me a grin

bdub.

On Thu, Apr 23, 2020, 7:27 AM Bruce Hislop via Gmclist <
gmclist@list.gmcnet.org> wrote:

> For in-tank pumps, if you stay with the carb you will need low pressure
> pumps. Then when you change to EFI, you will need to change the pumps to
> high
> pressure units. So you might want to save the $250 for low pressure pumps
> and goto EFI now.
>
> just saying.
>
> --
> Bruce Hislop
> ON Canada
> 77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
> My Staff says I never listen to them, or something like that
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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bdub
bdub.net
Re: In tank fuel pump question [message #354041 is a reply to message #354021] Thu, 23 April 2020 10:41 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
Ken m, here's a setup that cured vapor lock in the Southeastern summertime:

http://www.gmcmhphotos.com/photos/g6198-cane-9-creek-rv-park-heflin-2c-al.html

Note that this uses the existing line which ran originally from the selector forward and the lines that come from the tanks. Which you should replace if they haven't been. Note the fitting on the hardline to the carb and the blank flange to the side of the block. If you carry a spare mechanical pump, you can revert to stock beside the road in a matter of minutes should this become necessary. There are two caveats: First, run the pump power either through an oil pressure switch or a Ford mid - 00s safety switch. The Ford switch is a somewhat easier install but both will shut the pump off in an accident. Second, replace the supplied (heathen chinee)filters with a pair of Wix replacements. The chionee filters fail at the swaged connection and draw air.
I've personally no great favor for in - tank pumps, my MSD injection wants ~~ 50 PSI which it gets from the supplied in - line pump attached to the frame rail inside. It's given no trouble in three years. I will note however, I finally pulled out the spare pump the PO had, and looked at it. Low pressure fro a carbureted engine. I'll be replacing it

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: In tank fuel pump question [message #354042 is a reply to message #354021] Thu, 23 April 2020 10:52 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
Oh and let me point out for the uninitiated, I'm personally two things which are anathema to most of our GMCers:

1. Cheap
2. Lazy

These dictate a fair amount of stuff I do to my coach including the listed fuel system uupgrade.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: In tank fuel pump question [message #354050 is a reply to message #354021] Thu, 23 April 2020 12:55 Go to previous messageGo to next message
Glenn is currently offline  Glenn   Canada
Messages: 92
Registered: February 2004
Location: Northwestern Ontario
Karma: 2
Member
Check to ensure in-tank fuel pumps have built in check valves. If not you will need to install in-line check valves.

HTH.........
Glenn
76 Glensbroke
Re: In tank fuel pump question [message #354054 is a reply to message #354021] Thu, 23 April 2020 13:23 Go to previous messageGo to next message
Husker92592 is currently offline  Husker92592   United States
Messages: 137
Registered: August 2013
Location: Temecula ca
Karma: -4
Senior Member
I used the following nag and made my own with a return line:

FUEL PUMP


NEW AC DELCO FUEL PUMP & STRAINER KIT

AC DELCO # EP386

GM # 25168719

DELPHI # FE0115

GLOBAL AUTOMOTIVE # GA3902

CARTER # P60852, P74000, P74002

BOSCH # 69238

DENSO # 9515017



Sending unit:

1973 - 1978
GM B Body
Fuel / Gas Tank Sending Unit 3/8" 3 Line

FG110B


You have to makes some cuts and bends but cheaper then buying “ OEM” or you’re original rebuilt. I purchased a rebuilt sending unit and never worked infurior plastic sending unit and cost over $200.

My two cents


1974 GMC Sequoia 26'
Re: [GMCnet] In tank fuel pump question [message #354062 is a reply to message #354023] Thu, 23 April 2020 13:57 Go to previous message
Dave is currently offline  Dave   United States
Messages: 32
Registered: March 2004
Karma: 3
Member



I did not see the original post (on the e-mail list) but here is how
I did my in tank fuel pump (and other fuel system) upgrades back in
2013. I have not had fuel supply problems since...

http://www.gmcmhphotos.com/photos/g6555-in-tank-fuel-pumps.html

Hopefully you will find something useful here...

Dave
Ann Arbor, MI.
73 Sequoia (26'/455/EbH/RwI/ThH/HEI/TBI/160°/3.42/100A/Q55G)



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