EFI vs Carb

I had to do an in tank pump in a suburban (99 with 140k)

Know of several other gm in tank pump models with same issue. It’s not
terribly uncommon with gm stuff of that and newer vintage. Astro vans come
to mind. But if you have two pumps ( one in each tank) you would not have
to mess with it until you got home. Which is a lot better than climbing
under the rig and beating on the tank to spur the pump.

Sully
77 eleganza 2
Bellevue.

> Sorry, that was a 1993 Jeep Grand Cherokee but that’s still 22 years and
> 300,000 miles of usage on the original in-tank fuel pump.
>
> The eight year old ones in my GMC now have about 130,000 miles on them.
>
> Emery Stora
>

> >
> > True, but how often are you planning to replace them?
> >
> > Mine have been in for 8 years now and are still working fine.
> >
> > If one were to fail then I still have the other — or if I didn’t have
> the time to replace an in-tank one I could always hook up an outside the
> tank one temporarily. The in-tank pumps do allow fuel to be pulled through
> it by an external pump.
> >
> > The in-tank pump in my 1973 Jeep Grand Cherokee still worked after 42
> years when I traded it in. How many of you have ever had to replace an
> electric in-tank pump in their automobile?
> >
> > Emery Stora
> > 77 Kingsley
> > Frederick, CO
> >
> >
> >> On Nov 28, 2017, at 1:33 PM, John Phillips

> >>
> >> But i-tank pumps are harder to replace.
> >>
> >>> On Tue, Nov 28, 2017 at 11:17 AM, Jon Roche

> >>>
> >>> You need to do some more research as many have easily installed without
> >>> raising the hatch. It does require normally a remote air filter. I
> >>> think
> >>> applied has some varients that should be complete kits.
> >>>
> >>> No need for maf sensor, just need to get filtered air to the fi-tech.
> >>>
> >>> Fuel delivery is the wild card as there are people happy with the fcc,
> >>> and others have experienced issues.
> >>>
> >>> Call those that have some miles on there setup. Lots of work, but i
> >>> think the best way is to get in-tank pumps. I do not hear of problems
> with
> >>> people get in-tank pumps. Sure the pump can die, but all pumps can
> die.
> >>> --
> >>> Jon Roche
> >>> 75 palm beach
> >>> St. Cloud, MN
> >>> http://lqqkatjon.blogspot.com/
> >>>
> >>> _______________________________________________
> >>> GMCnet mailing list
> >>> Unsubscribe or Change List Options:
> >>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >>>
> >>
> >>
> >>
> >> --
> >>
> >> *John Phillips*
> >> _______________________________________________
> >> GMCnet mailing list
> >> Unsubscribe or Change List Options:
> >> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> >
> > _______________________________________________
> > GMCnet mailing list
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>
 
I had to replace the in-tank pump in an Audi--a very good Bosch pump. Any
pump can fail.

Rick "since you asked :) " Denney

> True, but how often are you planning to replace them?
>
> Mine have been in for 8 years now and are still working fine.
>
> If one were to fail then I still have the other — or if I didn’t have the
> time to replace an in-tank one I could always hook up an outside the tank
> one temporarily. The in-tank pumps do allow fuel to be pulled through it
> by an external pump.
>
> The in-tank pump in my 1973 Jeep Grand Cherokee still worked after 42
> years when I traded it in. How many of you have ever had to replace an
> electric in-tank pump in their automobile?
>
> Emery Stora
> 77 Kingsley
> Frederick, CO
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Rick Denney
73 x-Glacier 230 "Jaws"
Off-list email to rick at rickdenney dot com
 
I have dealt with numerous electric fuel pump failures.

Funny about chevy astro's. We changed quite a few. I remember getting one replaced under warantee only to have our mechanic break the replacement
trying to install the lock ring. That was a $400 whoops.

Once on a Chevy suburban.

Couple ford e-250's.

My 93 cherokee never had an issue. But my 98 jeep wrangler lost a pump as did a friend's 94 wrangler.

3-4 fuel pumps on my vw sand rail. Those I should not count, but I can think of a few after market fuel pumps that were installed in a gmc motorhome
that went bad.

I also live where it is -30 some weeks in winter and 100 in summer. Winters are hard on fuel pumps.

--
Jon Roche
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/
 
G'day,

I intend to install low pressure in-tank pumps (7 psi) to feed a surge tank up front which can feed the mechanical fuel pump or a
high pressure FI pump. The surge tank will have a return plumbed into the 1/2 inch vent tube for the fuel filler.

1) cut off the tubes off a defective tank sender
2) drill a hole in the center of the tank sender
3) put a screw with a sharpened end through the hole and install in the tank(s)
4) raise the tank(s) into position
5) the screw will put a mark on the aluminum sheet that covers the Styrofoam insulation
6) drill a 1/8 inch hole up through the aluminum sheet, Styrofoam, and plywood floor
7) using the 1/8 inch hole as a guide cut a 6 inch hole using a fly cutter
8) using a router along the edge of the 6 inch hole create a step for a 1 inch thick plug with a stepped edge
9) cover the floor with high grade vinyl
10) carefully cut out the 6 inch hole in the vinyl and glue it to the plug
10) make a custom fit carpet to cover the area and bind the edges

This will provide access to the pumps should they require replacement.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Jon Roche
Sent: Wednesday, November 29, 2017 7:26 AM
To: gmclist
Subject: Re: [GMCnet] EFI vs Carb

i agree in-tank pumps are both harder to install, and harder to change. But when you talk to those that went that route it seems
vapor lock is gone.

There are trade off's to all systems. A person has to make up there own mind and live with it.
--
Jon Roche
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/
 
My personal experiences with Mopar in tank pump assemblies in Jeeps is they are very long lived compared to most other high pressure in tank pumps in
the industry, which are short lived. Back to the GMC carb vs EFI debate-- if the reason for doing it is vapor lock, that can be corrected by
installing an external feed through low pressure pump near the Aux tank and opperated via the existing Aux seitch via a relay with total parts costs
well under $100. I have found all the wrapping and insulating a futile exercise. VL occurs before the mech pump in my opinion. Flip the switch and
it's fixed every time. Also a well set up Qjet will start smoothly, transition cold to warm seamlessly and be very dependable. The only reason I
would go to EFI is if I lived or drove a lot at altitude. It can't add air density but can pull fuel automatically at altitude keeping the engine
more in the correct range to make the most of the thin air
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Thanks again everyone for your input.

John, Vapor Lock is one reason for considering EFI, the main reason is peace of mind for all-around driving. I live in Ontario, Canada, not much in
the way of altitude in my area although I plan to drive to California in the spring.

I would like reliability, I realize there are challenges with both systems and that a properly tuned carb and distributor can address my concerns. I
wasn't looking for a reason to spend two thousand dollars for an EFI set-up, I simply understood that an EFI system could be a more efficient and a
potentially less troublesome route... everyone has their own opinion and experience with each.

My initial post asked for real world experiences rather than anecdotal opinions so I could base my choice on practical over theory. I
was directed to FaceBook as there is a group that discusses the Fitech set-up in the GMC motorhome, unfortunately I'm not a FB guy.

The quest continues,
Thanks,
Mike
 
Rob-

2 quick things.
Do you know anybody who has cut the holes in the floor and what diameter and have r+r there fuel pumps through that hole??
I see that option talked about, and good in theory, I never heard how well it worked out in real life. I keep thinking you need a really big hole
to manouver the fuel pump in and out of the tank, as well as getting the lock rings twisted and in place square and proper. Not saying it cant be
done, but when I have looked at accessing the fuel senders 2-3 " below the floor, i wonder how big of a hole is needed to service?

2nd item is when I have had fuel tanks down it is more then obvious where to drill up. The last coach I did, i hole sawed out the foam, and drilled
up into carpet with a 1/4" bit. You wont need to lift the tank to mark anything from bottom.

If you look at my photos you will see the factory already has a hole for senders. At least on my 75 and the 77 i did tanks on.

--
Jon Roche
75 palm beach
St. Cloud, MN
http://lqqkatjon.blogspot.com/
 
I have 6" holes in the floor rabbited out to 7" on top 1/2" so the cover
won't fall out. I had to put on a new 2" piece of fuel resistant hose to
couple the fuel pump to the output tube. My first one disintegrated after
a couple of months and left me dead on the side of the road. Yes, I
switched pumps to pull from but that pressure went straight into the rear
tank because the pump connection wasn't there to stop it! Anyhow, I was
able to easily pull out the pump and sender assembly, repair, and
re-assemble without any trouble. Even with the o-ring seal.

bdub

> Rob-
>
> 2 quick things.
> Do you know anybody who has cut the holes in the floor and what diameter
> and have r+r there fuel pumps through that hole??
> I see that option talked about, and good in theory, I never heard how well
> it worked out in real life. I keep thinking you need a really big hole
> to manouver the fuel pump in and out of the tank, as well as getting the
> lock rings twisted and in place square and proper. Not saying it cant be
> done, but when I have looked at accessing the fuel senders 2-3 " below the
> floor, i wonder how big of a hole is needed to service?
>
> 2nd item is when I have had fuel tanks down it is more then obvious where
> to drill up. The last coach I did, i hole sawed out the foam, and drilled
> up into carpet with a 1/4" bit. You wont need to lift the tank to mark
> anything from bottom.
>
> If you look at my photos you will see the factory already has a hole for
> senders. At least on my 75 and the 77 i did tanks on.
>
> --
> Jon Roche
> 75 palm beach
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Oh and don't bet the farm on those existing cutouts in the insulation being
perfect fit for the tanks. Both mine were off about a half inch.

bdub

-----Original Message-----
From: Gmclist On Behalf Of Jon Roche
Sent: Wednesday, November 29, 2017 2:50 PM

2 quick things.
Do you know anybody who has cut the holes in the floor and what diameter and
have r+r there fuel pumps through that hole??
I see that option talked about, and good in theory, I never heard how well
it worked out in real life. I keep thinking you need a really big hole
to manouver the fuel pump in and out of the tank, as well as getting the
lock rings twisted and in place square and proper. Not saying it cant be
done, but when I have looked at accessing the fuel senders 2-3 " below the
floor, i wonder how big of a hole is needed to service?

2nd item is when I have had fuel tanks down it is more then obvious where to
drill up. The last coach I did, i hole sawed out the foam, and drilled
up into carpet with a 1/4" bit. You wont need to lift the tank to mark
anything from bottom.

If you look at my photos you will see the factory already has a hole for
senders. At least on my 75 and the 77 i did tanks on.
 
Mike, if you want piece of mind--you can't beat a Qjet. As far as efficiency, I have never seen a post here about how they get better MPG with EFI.
Have seen several posts about dead in water with EFI or orphaned systems with no parts and support.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
> Rob-
>
> 2 quick things.
> Do you know anybody who has cut the holes in the floor and what diameter and have r+r there fuel pumps through that hole??
> I see that option talked about, and good in theory, I never heard how well it worked out in real life. I keep thinking you need a really big
> hole to manouver the fuel pump in and out of the tank, as well as getting the lock rings twisted and in place square and proper. Not saying it
> cant be done, but when I have looked at accessing the fuel senders 2-3 " below the floor, i wonder how big of a hole is needed to service?
>
> 2nd item is when I have had fuel tanks down it is more then obvious where to drill up. The last coach I did, i hole sawed out the foam, and
> drilled up into carpet with a 1/4" bit. You wont need to lift the tank to mark anything from bottom.
>
> If you look at my photos you will see the factory already has a hole for senders. At least on my 75 and the 77 i did tanks on.

We made floor access for in tank pumps. 1/8 aluminium plates recessed to floor level over a 6 inch hole. Self adhesive floor tile over it. Marked hole
location while the tanks were out and I could see where the senders actually were by rub marks.
http://wallyandsue.blogspot.com/2014/07/floor-plates-for-access-to-fuel-senders.html
http://wallyandsue.blogspot.com/2014/07/floor-plates-for-access-to-fuel-senders.html
HTH
--
Wally Anderson
Omaha NE
75 Glenbrook
Megasquirt III injection
Bob Stone hydroBOOOOST
Manny reaction arm system
Branscombe Kelsey Hayes park brake
http://wallyandsue.blogspot.com/
 
Wally,

Thanks for responding to this thread, I didn't realize that the tanks were as far forward as they are. I really like the self
adhesive floor tile idea.

I note you've used what appears to be 3/8' flareless fittings to connect the senders to what appears to be Poly Armour tubing, I
have Swagelok 3/8" flareless to 38 degree male stainless steel fittings. The flareless connection would connect to the sender
fittings and the flared connection to the Poly Armour tubing.

How did you connect the lines that go across the top of the tank to the lines that go up the side of the coach in the frame rails? I
plan on having some braided stainless steel flex hoses made up for that purpose.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Wally Anderson
Sent: Wednesday, November 29, 2017 5:53 PM
To: gmclist
Subject: Re: [GMCnet] EFI vs Carb

> Rob-
>
> 2 quick things.
> Do you know anybody who has cut the holes in the floor and what diameter and have r+r there fuel pumps through that hole??
> I see that option talked about, and good in theory, I never heard how well it worked out in real life. I keep thinking you need
a really big
> hole to manouver the fuel pump in and out of the tank, as well as getting the lock rings twisted and in place square and proper.
Not saying it
> cant be done, but when I have looked at accessing the fuel senders 2-3 " below the floor, i wonder how big of a hole is needed to
service?
>
> 2nd item is when I have had fuel tanks down it is more then obvious where to drill up. The last coach I did, i hole sawed out
the foam, and
> drilled up into carpet with a 1/4" bit. You wont need to lift the tank to mark anything from bottom.
>
> If you look at my photos you will see the factory already has a hole for senders. At least on my 75 and the 77 i did tanks on.

We made floor access for in tank pumps. 1/8 aluminium plates recessed to floor level over a 6 inch hole. Self adhesive floor tile
over it. Marked hole
location while the tanks were out and I could see where the senders actually were by rub marks.
http://wallyandsue.blogspot.com/2014/07/floor-plates-for-access-to-fuel-senders.html
http://wallyandsue.blogspot.com/2014/07/floor-plates-for-access-to-fuel-senders.html
HTH
--
Wally Anderson
Omaha NE
75 Glenbrook
Megasquirt III injection
Bob Stone hydroBOOOOST
Manny reaction arm system
Branscombe Kelsey Hayes park brake
http://wallyandsue.blogspot.com/

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Rob, I used Dorman nylon fuel tube like newer cars and trucks use OEM. Those Dorman fittings are made to go from steel tube to their nylon tube. Same
scheme to connect the forward end.
I did put external check valves in both pump lines as I had read of others who had issues if a pump check sticks open or a line comes off in the tank
leading to an instant stop.
So far so good.

> Wally,
>
> Thanks for responding to this thread, I didn't realize that the tanks were as far forward as they are. I really like the self
> adhesive floor tile idea.
>
> I note you've used what appears to be 3/8' flareless fittings to connect the senders to what appears to be Poly Armour tubing, I
> have Swagelok 3/8" flareless to 38 degree male stainless steel fittings. The flareless connection would connect to the sender
> fittings and the flared connection to the Poly Armour tubing.
>
> How did you connect the lines that go across the top of the tank to the lines that go up the side of the coach in the frame rails? I
> plan on having some braided stainless steel flex hoses made up for that purpose.
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces] On Behalf Of Wally Anderson
> Sent: Wednesday, November 29, 2017 5:53 PM
> To: gmclist
> Subject: Re: [GMCnet] EFI vs Carb
>

> > Rob-
> >
> > 2 quick things.
> > Do you know anybody who has cut the holes in the floor and what diameter and have r+r there fuel pumps through that hole??
> > I see that option talked about, and good in theory, I never heard how well it worked out in real life. I keep thinking you need
> a really big
> > hole to manouver the fuel pump in and out of the tank, as well as getting the lock rings twisted and in place square and proper.
> Not saying it
> > cant be done, but when I have looked at accessing the fuel senders 2-3 " below the floor, i wonder how big of a hole is needed to
> service?
> >
> > 2nd item is when I have had fuel tanks down it is more then obvious where to drill up. The last coach I did, i hole sawed out
> the foam, and
> > drilled up into carpet with a 1/4" bit. You wont need to lift the tank to mark anything from bottom.
> >
> > If you look at my photos you will see the factory already has a hole for senders. At least on my 75 and the 77 i did tanks on.
>
> We made floor access for in tank pumps. 1/8 aluminium plates recessed to floor level over a 6 inch hole. Self adhesive floor tile
> over it. Marked hole
> location while the tanks were out and I could see where the senders actually were by rub marks.
> http://wallyandsue.blogspot.com/2014/07/floor-plates-for-access-to-fuel-senders.html
> http://wallyandsue.blogspot.com/2014/07/floor-plates-for-access-to-fuel-senders.html
> HTH
> --
> Wally Anderson
> Omaha NE
> 75 Glenbrook
> Megasquirt III injection
> Bob Stone hydroBOOOOST
> Manny reaction arm system
> Branscombe Kelsey Hayes park brake
> http://wallyandsue.blogspot.com/
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

--
Wally Anderson
Omaha NE
75 Glenbrook
Megasquirt III injection
Bob Stone hydroBOOOOST
Manny reaction arm system
Branscombe Kelsey Hayes park brake
http://wallyandsue.blogspot.com/
 
Wish I'd a used those check valves.

bdub

Rob, I used Dorman nylon fuel tube like newer cars and trucks use OEM.
Those Dorman fittings are made to go from steel tube to their nylon tube.
Same scheme to connect the forward end.
I did put external check valves in both pump lines as I had read of others
who had issues if a pump check sticks open or a line comes off in the tank
leading to an instant stop.
So far so good.
 
Wally,

I want to use Poly Armour and put it on the outside of the frame because I'm hoping to plumb the water that condenses on the A/C
evaporator to the fuel line and the latent heat of vaporization will cool the fuel.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces] On Behalf Of Wally Anderson
Sent: Wednesday, November 29, 2017 9:08 PM
To: gmclist
Subject: Re: [GMCnet] EFI vs Carb

Rob, I used Dorman nylon fuel tube like newer cars and trucks use OEM. Those Dorman fittings are made to go from steel tube to their
nylon tube. Same scheme to connect the forward end.
I did put external check valves in both pump lines as I had read of others who had issues if a pump check sticks open or a line
comes off in the tank leading to an instant stop.
So far so good.
 
> Wally,
>
> I want to use Poly Armour and put it on the outside of the frame because I'm hoping to plumb the water that condenses on the A/C
> evaporator to the fuel line and the latent heat of vaporization will cool the fuel.
>
> Regards,
> Rob M.

Rob,

In April of 2012, I replaced just about all the rubber fuel line with Ployarmor. I used a jewelers saw (very fine hacksaw) to cut the bubble off the
fittings on the tank access and then used brass compression fittings to make the connection. That makes 5 years and about 40K miles that they have
been good. I cheated, I copied what Emery did.

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
 
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