surge tank versus in fuel tank pump

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marc
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surge tank versus in fuel tank pump

Post by marc »

Contemplating putting fuel injection on my 84 j10. The cranky old BBD carb is frustrating. In my research, I have seen people posting about in line pumps, in tank pumps and surge tanks. My fuel injection experience which is very out of date, early VW systems with cranky injectors, leads me to think that the more opportunities for fuel purification the better so a filter into the surge tank, a surge tank to settle particulates and a filter into the TBI seems to me a way to help with reliability. I am wondering what more experienced folks think about the options? As the truck might migrate back to Calif., I want to keep that emission option open.
Thanks, Marc
J10 1984, very stock with AMC 258.
Truck appears to have been rebuilt or restored at one time
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Yeller
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Re: surge tank versus in fuel tank pump

Post by Yeller »

I have several rigs been running EFI for a few decades trouble free. 2 of them have even migrated from TBI to port injection. They all have in line pumps with a standard paper inline pre filter before the pump and a fuel injection rated inline filter after the pump. No special pick ups in the tank, just standard carburetor era pick ups in the tank. No surge tank, have never found that they do anything other than sound good on paper and look fancy. I tend to use my vehicles in ways that most wouldn’t dream of and only time I’ve had issues is when they were in dire need of fuel anyway, as in 2 gallons from walking. Keep it simple. Simple is reliable.

Once you go fuel injection you’ll never want another carb. I’ve been running EFI since 1989 and did it as a high school kid because I was told it would never work.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

1970 J2500 Resto Mod
https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

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Topic author
marc
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Re: surge tank versus in fuel tank pump

Post by marc »

Yeller, do yu use the original fuel pickup from the tank?
J10 1984, very stock with AMC 258.
Truck appears to have been rebuilt or restored at one time
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Yeller
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Re: surge tank versus in fuel tank pump

Post by Yeller »

Yes I do, I just get the pump and pre filter as close to the tank as reasonably possible along with the pump as low as possible. The pumps do not suck efficiently and need to be low enough to have mostly a siphon, the pump doesn’t have to be as low or lower than the tank, just as low as reasonably possible.

This is the pump I’ve been running.
https://www.amazon.com/Walbro-GSL392-Fu ... 13d670b6bc

Pre filter
https://www.amazon.com/WIX-Filters-Comp ... 194&sr=8-3

Fuel injection filter
https://www.amazon.com/Herko-Chevrolet- ... erado+1500
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

1970 J2500 Resto Mod
https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

1974 Bronco “Broncno”
https://classicbroncos.com/forums/threa ... st-3411909
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tgreese
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Re: surge tank versus in fuel tank pump

Post by tgreese »

It is possible to run a surge tank with the original fuel pickup. No mods to the fuel tank needed. Works with either the original mechanical pump or a low-pressure electric pump near the fuel tank. Many Fords run this arrangement from the factory; the frame-mounted cartridge pump (like the above Walbro) was used with a low-pressure helper pump in or near the tank.

A spin-on fuel filter makes a nice surge tank. There's a thread on IFSJA that may help http://web.archive.org/web/201506051224 ... stcount=34

Hopefully you can see it via the Wayback. I can't view the EFI forum currently.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
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Srdayflyer
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Re: surge tank versus in fuel tank pump

Post by Srdayflyer »

my friend tried the surge tank but had issues with vapor lock, and had problems when he was at ouray 21, at altitudes above 7500 ft, 1 of the problems with fuel injection systems, is everyone trys to use the factory supply and return lines. the carb return line is 1/4 inch and creates back pressure issues with f.i. systems, i am running the holly sniper and had to run 3/8" lines per their recommendation, as they found anything less causes issues with excess back pressure in the sniper, and drivability problems

sierrablue
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Re: surge tank versus in fuel tank pump

Post by sierrablue »

Somewhat late reply (sorry). Since I don't have TBI yet I haven't been browsing the EFI stuff much.

The external pump will work, however you probably want an in-tank pump. BJ's (among others) sells in-tank pumps now for FSJs--I don't know if they make them for all of them, but some of them. With the in-tank, the fuel keeps it cool, so you know vapor lock won't be an issue, and also (the bigger one if it's a driver) you don't have to listen to that stupid pump whining super loudly on the frame. It's incredibly annoying to listen to.
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
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-Front shoulder belts (rears eventually)

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There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.

dddonkey
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Re: surge tank versus in fuel tank pump

Post by dddonkey »

I run a surge tank on my Jeep. I have the Holley Sniper kit with no issues and a very easy install. My fuel system uses the factory tank to a 12v inline low pressure pump, to the McRobb surge tank, to the Holley system, back to the surge tank, then back to the OEM tank. I have had no vapor lock issues at all, the only special task I do is wait to start the Jeep once the key is in the run position so that the system can start the Computer and prime the fuel system. This was a cheaper set up than replacing the tank.
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Renodemona
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Re: surge tank versus in fuel tank pump

Post by Renodemona »

When I ran a TBI system lifted off a 87ish GMC truck I ran a small inline pump and re-used all the factory stuff in the tank, just replaced the sock with a new one. I did not encounter any problems, although the pump was rather loud. I did burn out a fuel pump and changed it on the side of the road, although I think that was mostly down to my choice of a Cheapo amazon pump. When I swapped over to FiTech I converted to an in-tank pump that had a higher flow and pressure that would be able to support fuel rail delivery for a one day engine swap. I encountered several problems with the in tank pump until eventually settling on a kit that worked for me. I changed over to a poly fuel tank and used a factory style fuel pick up modified with a Walbro stuck on the end of it. Unfortunately there was no stabilization and it just kinda flopped around and had poor pickup. This was more down to me not thinking about it, and sure enough it eventually flopped itself into slicing the plastic insulation on a wire and shorted itself out at the bulkhead connector. Take 2 back to the metal tank with the aforementioned kit where you drill a big circle in the top and the included parts clamp together with a baffle thing you cut to fit in the bottom and secure the fuel pump to. Bingo Bango, much more secure and better flow without sloshing though a LOT more work to prep the tank. No issues with that setup.

My takeaways (I'm not a Doctor or an expert):
Running low pressure EFI like TBI, you can use all the same stuff for the Carb. GM specifically designed their system to do this to save $$$. Frame mounted fuel pumps work fine, but they can be prone to failure by getting hot. Keep a spare in the tool box just in case. Frame mounted high pressure fuel pumps have more tendency to get hot and fail, if you don't need high pressure, don't put it on.
High pressure EFI like 255/58psi need bigger fuel lines to be the happiest. I run 3/8 delivery and re-used the 5/16 as the return. In-tank fuel pumps seem to last a lot longer sitting in nice cool liquid to dissipate heat and save the bearings. Always use stuff designed to for fuel systems, be it the special JB weld or insulation or that goopy stuff.
Surge Tank vs main tank, I was always told...surge tank in a rollover is bad news since it puts a lot of gas on that nice hot exhaust next to the nice hot engine. Obviously a rollover is bad in general, but fire is bad.

Tl/DR edition:
In-tank is a lot more work up front but keeps things simpler and reliable (modern cars do this), if you have TBI just throw a frame rail pump on there and let it rip.
"Wait, what's on fire!?" KJ7TCT
--------------------------------------------------------------
1976 Cherokee w/t 'Susan' 401/TH400/QT(PT)
FiTech Go EFI, Edelbrock Performer intake
3" Rough Country Springs, HEI Dizzy
-------------------------------------------------------------
2018 Cherokee Trailhawk V6 'Sedna'
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Renodemona
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Re: surge tank versus in fuel tank pump

Post by Renodemona »

Addition:
I didn't see the California Emissions part. Howell is the only system that has a CARB sticker and it is TBI based. In their kit they give you a good frame rail pump. If Emissions testing is in your future, this is probably a good option since anything else the Kommisar of Smog will say is Verboten!
"Wait, what's on fire!?" KJ7TCT
--------------------------------------------------------------
1976 Cherokee w/t 'Susan' 401/TH400/QT(PT)
FiTech Go EFI, Edelbrock Performer intake
3" Rough Country Springs, HEI Dizzy
-------------------------------------------------------------
2018 Cherokee Trailhawk V6 'Sedna'
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Greg72
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Re: surge tank versus in fuel tank pump

Post by Greg72 »

Yeller wrote: Sun Jan 15, 2023 5:44 pm Yes I do, I just get the pump and pre filter as close to the tank as reasonably possible along with the pump as low as possible. The pumps do not suck efficiently and need to be low enough to have mostly a siphon, the pump doesn’t have to be as low or lower than the tank, just as low as reasonably possible.

This is the pump I’ve been running.
https://www.amazon.com/Walbro-GSL392-Fu ... 13d670b6bc

Pre filter
https://www.amazon.com/WIX-Filters-Comp ... 194&sr=8-3

Fuel injection filter
https://www.amazon.com/Herko-Chevrolet- ... erado+1500


HA!

Every time I am searching around on this message forum for a topic that interests me, it seems like you are always one of the respondents dishing out all of the "goods" on how to accomplish it.

I'm going to remember you..... :)


BTW -> Is there such a thing as an "@ mention" on this forum? It's nice sometimes to specifically call out someone so that they are aware that you would like them to share an opinion.


-G
1989 Jeep Grand Wagoneer - !! NEW !!
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Yeller
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Re: surge tank versus in fuel tank pump

Post by Yeller »

Greg72 wrote: Thu Aug 17, 2023 6:09 pm
Yeller wrote: Sun Jan 15, 2023 5:44 pm Yes I do, I just get the pump and pre filter as close to the tank as reasonably possible along with the pump as low as possible. The pumps do not suck efficiently and need to be low enough to have mostly a siphon, the pump doesn’t have to be as low or lower than the tank, just as low as reasonably possible.

This is the pump I’ve been running.
https://www.amazon.com/Walbro-GSL392-Fu ... 13d670b6bc

Pre filter
https://www.amazon.com/WIX-Filters-Comp ... 194&sr=8-3

Fuel injection filter
https://www.amazon.com/Herko-Chevrolet- ... erado+1500


HA!

Every time I am searching around on this message forum for a topic that interests me, it seems like you are always one of the respondents dishing out all of the "goods" on how to accomplish it.

I'm going to remember you..... :)


BTW -> Is there such a thing as an "@ mention" on this forum? It's nice sometimes to specifically call out someone so that they are aware that you would like them to share an opinion.


-G
I take that as a challenge and a compliment 😂

I love building, but can’t build them all. If I can help you build a more reliable ride, you’ll use and enjoy it more and that is what it’s all about.

Unfortunately no @xxxx on this site. It’s handy but I’m old enough to enjoy the simplicity and old school feel lol.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

1970 J2500 Resto Mod
https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

1974 Bronco “Broncno”
https://classicbroncos.com/forums/threa ... st-3411909
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Greg72
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Re: surge tank versus in fuel tank pump

Post by Greg72 »

Yeller wrote: Thu Aug 17, 2023 7:55 pm

I take that as a challenge and a compliment 😂

I love building, but can’t build them all. If I can help you build a more reliable ride, you’ll use and enjoy it more and that is what it’s all about.

Unfortunately no @xxxx on this site. It’s handy but I’m old enough to enjoy the simplicity and old school feel lol.

Right on! I'm definitely "peeling the onion" on this site (and YouTube) looking for all of the tech info I need to get my "new" Grand Wagoneer properly baselined. There is LOT of stuff that is broken or missing or incorrect. I've already figured out that the horrible driving experience on the highway was due to the lift kit and the way it eliminated all the positive caster in the front knuckles. The 6* leafspring shims should arrive today and that will be my first "real" repair/update in a long list of other necessary updates.

-G
1989 Jeep Grand Wagoneer - !! NEW !!
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ntsqd
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Re: surge tank versus in fuel tank pump

Post by ntsqd »

Yeller and I are on the same page about fuel filters. I use the Wix version of the same application fuel filter with o-ring bump to AN adapter fittings. I prefer those fittings to the adapters made for the later spring-lock EFI connections.

I used to think that external fuel pumps were the best way to go, but I have seen a couple reported vapor lock problems with them. That caused me to really think about these systems and what's going on in each section. I once looked up the boiling point of gasoline and then did the boiling point reduction calc for fuel under less than ambient pressure (like it is in any part of the system between the tank and the pump) and that was an eye opener! [Note that gasoline doesn't have fixed boiling point, it has a range of BP's since it is a composite of hydrocarbons. I took an average and worked my calc from there.] Doesn't take much vacuum to have fuel that is boiling at 70°F Do that in a suction line and you have vapor lock.

[EDITED]
Last edited by ntsqd on Tue Aug 29, 2023 3:43 pm, edited 1 time in total.
thom

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Yeller
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Re: surge tank versus in fuel tank pump

Post by Yeller »

I have only experienced that 1 time with a my set up. 110* day about 6 gallons of fuel in the tank and a long high speed highway run. Sat for about 20 minutes and fired right back up. You made me look, explains a lot of issues lol.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

1970 J2500 Resto Mod
https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

1974 Bronco “Broncno”
https://classicbroncos.com/forums/threa ... st-3411909
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ntsqd
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Re: surge tank versus in fuel tank pump

Post by ntsqd »

There are way too many success stories to try to claim it a bad idea, way too many! But I do think it worth thinking about.

I ran an external TBI pump on the Valiant and neither I or the current owner (as of last report) have ever had a problem with fuel delivery. He lives in MO and took it on a Power Tour that took them clear to FL and included some hot laps around Atlanta Motor Speedway. No issues.

Contrast that with on the Blanc-oh! ('96 FSB) I bought the "patch panel" for the rear floor so that should the in-tank pump go bad I don't have to drop the tank. Again.
thom

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Yeller
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Re: surge tank versus in fuel tank pump

Post by Yeller »

Definitely. Now that I’ve researched the fuel in vacuum thing I’m not redesigning my systems lol. They work.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

1970 J2500 Resto Mod
https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

1974 Bronco “Broncno”
https://classicbroncos.com/forums/threa ... st-3411909
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ntsqd
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Re: surge tank versus in fuel tank pump

Post by ntsqd »

I would be very hesitant to use or suggest too fine of filtration, or too much filtration, between the pump and the fuel tank. One big filter or pick-up sock that only gets the chunks that might cause the pump problems is good enough. Put the fine filtration after the pump.

Re: spin-on fuel filters as a surge tank or reservoir. Don't get too excited about that idea. None of the marine filter pads that I've installed (a dozen or so) have had a "draw straw" so once the fuel level is drawn down just a little you'll have an air-lock. Compound that with the filters that I have put on those filter pads usually have a disc about halfway down that will limit the max length of any added draw-straw. I'm not clear on why those are there, but every Sierra brand marine fuel filter that I've seen had it. Net result is likely about a pint of fuel or less available "in reserve."
I did take a spare Bilstein damper remote reservoir and turn it into an accumulator. Just to see if it would work, and it did. Problem is/was that the volume it holds, about a pint, also isn't worth the trouble.
thom

Where does that road go?
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