School me on fuel cells

i'm bumpin this yr old thread to rant a little..........

the TJ pump (at least mine) is maxed out at the 12" mark, it goes no further, and actually requires a little bit of pull to hold it down at 12". i'm hoping a full body of fuel will weight it down.

1 might assume GR knows a little something .......so why are they intentionally hanging the pumps over an inch off the bottom? but it is the only "TJ" cell i can find with a fuel trap around the pump assy.

MB is right at the 12" limit but, it's a slosh box with no trap at the pump, so at a 1/4 or less tank you could tip it and begin starve the fuel sys if your sitting there for more than that wet fuel sock/filter holds.

RCI and Summit make a tank with a trap for universal use with an internal pump assy., but it appears to not be constructed/configured in a way that leaves no room to place the large flat ring needed to hold the TJ pump assy., it's made for a small headed universal pump assy.

so in reality nobody makes a cell for a TJ OE pump that's built right. they are either the wrong depth or they have no fuel trap and none have any built in slosh control.


i really need to learn tig............i might try something like this.
perforated baffle walls to keep slosh down, tapered design to keep fuel at the pump, it would take a sufficient platform type mount to support correctly but could be done. (excuse the chicken scratch notes , it's hard to write with a mouse.)



cell.PNG



i'm gonna snag a 15gl rectangle from Summit, 30Lx9Wx12H, this should just work with a flat ring. it's the same rectangle as the MB. just 40$ less and close enough i can have it today. i'll fill both ends with foam and try and fit my baffles on either side of the pump assy to keep the foam trapped at the ends and the pump area free for the dam sending unit to function.

i also considered getting the 15gl 30Lx12Wx9H and having a custom job done to fit an 6-8" dia. x 2" deep cup onto the bottom, so the pump has a nice bowl trap to sit in.
 
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If I decide to go with a fuel cell this is the one I'm considering from GenRight.

https://genright.com/products/20-gallon-fuel-cell.html
The tanks offered by MB as you said don't have any baffles in them. I think I would also look into getting one of those Hydramats from Holley to help with extreme angles.

I still need to get under my Jeep and do some measuring to see if a GenRight tank would fit. I want to stay at 19 gallons since some of our trails are rather long and you can burn thru some fuel.

https://genright.com/products/jeep-tj-lj-crawler-ext-gas-tank-skid-plate-19-5-gal.html
 
If I decide to go with a fuel cell this is the one I'm considering from GenRight.

https://genright.com/products/20-gallon-fuel-cell.html
The tanks offered by MB as you said don't have any baffles in them. I think I would also look into getting one of those Hydramats from Holley to help with extreme angles.

I still need to get under my Jeep and do some measuring to see if a GenRight tank would fit. I want to stay at 19 gallons since some of our trails are rather long and you can burn thru some fuel.

https://genright.com/products/jeep-tj-lj-crawler-ext-gas-tank-skid-plate-19-5-gal.html
the way the OE pump is on the bottom it would take some work to use a Hydramat. i got somthin cooked up in my melon as always gonna stuff both ends of the cell with foam blocks and use overlapped U shaped walls like the GR to create an open area for the pump. those overlapped/interlocked U shaped boxes create a fuel pool lock that would work while going up or downhill.

the GR tank is a nice product but it's just to deep, the OE pump will be suspended, the filter sock will hang, it's about 1.25" to deep when on that cap. best bet would be to stand it on aluminum bracket and forget about that last 2" of fuel. what toximus did was a good way to handle it but you gotta have someone that can do it, and not cost more than the tank did.
 
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I run that Genright 19 gallon, and even with the 60 I was able to get my rear tires out to the bumper. My advice is to avoid pulling the tank inside. Unless you are building a full on dedicated crawler, it creates too many hassles IMO. Tox took an interesting route with his, but from what he says I know he’s not happy with it. Mine certainly does drag occasionally, but it’s never slowed me down.

And I think you are correct about the larger tank not working with your bags. I looked at their 23 tank, but the cut of the front corners would not work with my coilovers, and you also can’t get the exhaust past it. The 19 has the front corners angled to clear both.

Hope you get the heat worked out - it’s in the high 50’s here today and I’m hitting the road on the bike this afternoon (I just have to get it out of the living room...).
 
I run that Genright 19 gallon, and even with the 60 I was able to get my rear tires out to the bumper. My advice is to avoid pulling the tank inside. Unless you are building a full on dedicated crawler, it creates too many hassles IMO. Tox took an interesting route with his, but from what he says I know he’s not happy with it. Mine certainly does drag occasionally, but it’s never slowed me down.

And I think you are correct about the larger tank not working with your bags. I looked at their 23 tank, but the cut of the front corners would not work with my coilovers, and you also can’t get the exhaust past it. The 19 has the front corners angled to clear both.

Hope you get the heat worked out - it’s in the high 50’s here today and I’m hitting the road on the bike this afternoon (I just have to get it out of the living room...).

I'm not worried about it draggin as my old tank had a ton of drag marks on it . I am more worried about it not fitting. I've printed off their dimensions diagram so I can measure everything and see if it'll fit. If it doesn't I'll go back to using the fuel cell.
 
i'm bumpin this yr old thread to rant a little..........

the TJ pump (at least mine) is maxed out at the 12" mark, it goes no further, and actually requires a little bit of pull to hold it down at 12". i'm hoping a full body of fuel will weight it down.

1 might assume GR knows a little something .......so why are they intentionally hanging the pumps over an inch off the bottom? but it is the only "TJ" cell i can find with a fuel trap around the pump assy.

MB is right at the 12" limit but, it's a slosh box with no trap at the pump, so at a 1/4 or less tank you could tip it and begin starve the fuel sys if your sitting there for more than that wet fuel sock/filter holds.

RCI and Summit make a tank with a trap for universal use with an internal pump assy., but it appears to not be constructed/configured in a way that leaves no room to place the large flat ring needed to hold the TJ pump assy., it's made for a small headed universal pump assy.

so in reality nobody makes a cell for a TJ OE pump that's built right. they are either the wrong depth or they have no fuel trap and none have any built in slosh control.


i really need to learn tig............i might try something like this.
perforated baffle walls to keep slosh down, tapered design to keep fuel at the pump, it would take a sufficient platform type mount to support correctly but could be done. (excuse the chicken scratch notes , it's hard to write with a mouse.)



View attachment 199977


i'm gonna snag a 15gl rectangle from Summit, 30Lx9Wx12H, this should just work with a flat ring. it's the same rectangle as the MB. just 40$ less and close enough i can have it today. i'll fill both ends with foam and try and fit my baffles on either side of the pump assy to keep the foam trapped at the ends and the pump area free for the dam sending unit to function.

i also considered getting the 15gl 30Lx12Wx9H and having a custom job done to fit an 6-8" dia. x 2" deep cup onto the bottom, so the pump has a nice bowl trap to sit in.
No one runs foam long term. It all disintegrates and ruins the fuel system.
 
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And I think you are correct about the larger tank not working with your bags. I looked at their 23 tank, but the cut of the front corners would not work with my coilovers, and you also can’t get the exhaust past it. The 19 has the front corners angled to clear both.
Depends on how motivated one gets.

1604322682735.png


You can see the side of the tank is flush almost with the inside of the frame. What you don't see is there is an full length of 2 x 4 rectangular tube reinforcing the frame on the inside from bumper to wheel arch for the coil over notch.

1604323053191.png
 
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No one runs foam long term. It all disintegrates and ruins the fuel system.
Actually I figured out what I'd need and may go with baffle balls. I don't want foam really.
is there a product i'm missing or do y'all just leave them empty?
 
alright.............so i tore into the stock pump assy. i had to see/know whats goin on there.

what i find is, the can is our anti-starvation fuel containment device.
on the bottom of the can is the pre-filter.
inside the bottom of the can is a rubber washer and a steel washer. this seals the captured fuels outlet. above that sits another smaller strainer/screen device. this is mounted to the bottom of the pump by means of a rubber adapter.
then the pump is inline, into a push through seal and tube. this tube is crowned with a spring to keep pressure on the bottom end and keep it seated.
that tube from the pump is mated to the tube protruding down from our plastic caps by means of another push through seal.
the pumps height is limited by the 3 slotted legs that connect the top to the can.

so i'm not seeing a way to fit a Holley mat unless it can be fit to the existing can flange (which is not much of anything to grab and hold with any type of clamp). any alteration to the can bottom could result in the can not holding fuel unless it remains submerged as well.
so the cap holds the regulator. this dumps back through the cap into the can. this can is fairly deep and holds a good bit of fuel. Aeromotive has a similar design for their fancy high $ pumps that surrounds the pump in foam inside a plastic bowl........our can is about 3-4x as deep as their bowl.

so we don't wanna be punchin holes in the can or cuttin the bottom open........it is our fuel trap/baffle.

now baffle to me is not a fuel trap, and a fuel trap doesn't not qualify to me a baffling.
baffling is to control fluid movement, to me. splitting the vessel into smaller compartments, so liquid has less room to gain momentum and slow it's weight transfer from being abrupt and immediate.

i found 1 tank that's listed as 15gl, 30x12x12 that has walls that qualify as baffles. i don't like it has a vented cap that would need changed. so it'd need a ROV added, no need for the sending unit (but want the hole to get plastic baffles into) and i would not use the foot mounts, opting for a full surround mount to help control side wall flexing. not sure if i wanna go for it, but is another option.
https://fueltankparts.com/collections/universal-tanks/products/15-gallon-30x12x12-aluminum-tan
so part of this is, i think i was gettin tripped up trying to provide what already exists in addition to anti slosh, which was a fuel trap. not saying it's not possibly beneficial to add another, but maybe not completely necessary.

maybe y'all knew all this, but i think i have a slightly better understanding now.

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123435035_3910812588930481_3127462666850482589_n.jpg


123661781_697817384186361_538346600012045291_n.jpg
 
ya, an EFI tank is just a fuel trap, it would work to isolate our sending units from products like plastic balls or tubes (if it's tall enough), but still not really a true baffle.

none of the pre-made's really look to work well with a flat ring clamp the fitting configuration is to tight.
the 30x9x12 is the most open but the placement of the return fitting might not be the best to cover with the flat ring. and i'm not willing to buy 1 just to have a look.

that tank i posted has 2 wall to wall baffles top to bottom no transfer of additional baffle implements into the pump center pump area if i chose to use it.
 
ya, an EFI tank is just a fuel trap, it would work to isolate our sending units from products like plastic balls or tubes (if it's tall enough), but still not really a true baffle.

none of the pre-made's really look to work well with a flat ring clamp the fitting configuration is to tight.
the 30x12x9 is the most open but the placement of the return fitting might not be the best to cover with the flat ring. and i'm not willing to buy 1 just to have a look.

The reason I asked about the EFI is then you get away from using the stock fuel pump/sending unit. Then get a fuel level sender with the proper ohm's and you don't have to use the OEM stuff.


I used their custom tank form to see what one would cost and it came back around $700 for a 32x16x11 which was 21 gal.
 
i was attempting to keep it. it works. and it's paid for already.

i have the ring, i have the pump assy all i need is the right box to drop it into.
the EFI boxes all run about 300^ to 600^ w/pumps. pumps run 100 to well north of crazy. the TJ actually has a fairly good design for a regulator catch/anti-starve can.

i even considered closed cans and external pumps and regulator. but then we fall back to needing the right sump or multiple P/U's and a pump with lift.......a million things to try and take in.
 
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i was attempting to keep it. it works. and it's paid for already.

i have the ring, i have the pump assy all i need is the right box to drop it into.
the EFI boxes all run about 300^ to 600^ w/pumps. pumps run 100 to well north of crazy. the TJ actually has a fairly good design for a regulator catch/anti-starve can.

i even considered closed cans and external pumps and regulator. but then we fall back to needing the right sump or multiple P/U's and a pump with lift.......a million things to try and take in.

I get that it's already bought and paid for but switching to aftermarket stuff then gets you away from the worries of the stock unit not fitting the tank properly. I look at one of their EFI tanks in comparison to getting a GenRight fuel tank. The GR fuel tank is $1,400 and more if I want an aluminum skid. I could have a custom tank built with aftermarket fuel pump and stuff for less than that. If I just got a fuel cell and used the TJ pump assy then yes it's cheaper but could I come up with a better design/option?
 
I get that it's already bought and paid for but switching to aftermarket stuff then gets you away from the worries of the stock unit not fitting the tank properly. I look at one of their EFI tanks in comparison to getting a GenRight fuel tank. The GR fuel tank is $1,400 and more if I want an aluminum skid. I could have a custom tank built with aftermarket fuel pump and stuff for less than that. If I just got a fuel cell and used the TJ pump assy then yes it's cheaper but could I come up with a better design/option?

What aftermarket pumps are going to last as long as an OEM pump and not give troubles?
 
jeeps got 20yrs and 200k on OE pumps i'm not sweatin that. not reworking the vessel is all i want from this, 1 and done.

if i could find the right plastic tank i'd never even consider aluminum and house it in a steel can w/lid.

@toximus , since your here how tall was the inner box on that GR tank ? did it come up high enough to keep baffle balls or tubes off the pump assy? did it have room for the sending unit to function?
 
What aftermarket pumps are going to last as long as an OEM pump and not give troubles?

Have no idea if there is one that does/will since I've never played with any. But that wasn't the issue Someguy was talking about. He's worried about the stock pump not touching the bottom of the tank and fuel slosh and fuel starving. So if you were having a custom tank built with an aftermarket pump setup you could mitigate these issues. From all the reading I have done out of tank pumps seem to be part of the problem becasue they are not cooled. They now offer in-tank aftermarket pumps so will they last longer?
I've only ever ran a electric fuel pump once and I never had problems with it but I only owned that rig for 2 years.
 
jeeps got 20yrs and 200k on OE pumps i'm not sweatin that. not reworking the vessel is all i want from this, 1 and done.

if i could find the right plastic tank i'd never even consider aluminum and house it in a steel can w/lid.

@toximus , since your here how tall was the inner box on that GR tank ? did it come up high enough to keep baffle balls or tubes off the pump assy? did it have room for the sending unit to function?

I had to cut out the box for the TJ pump to fit in and for the sending arm to fit. It's roughly 4"x4"x1". Since the TJ pump has a built in sump I didn't see a purpose of keeping it anyway. Besides, I think a trap would work better than their maze if that's indeed a concern.

A baffle wall or two to slow sloshing on fast turns seems to be a decent benefit even if only to stiffen up the tank and stop fuel from hitting the sides so hard. But even then I'm not convinced it's necessary.

Anyway, I'm happy with how my cell turned out. That said, if you can fit it under the Jeep, it's easier and leaves more room inside for other stuff.
 
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Btw - You can extend the TJ pump. I covered that in my build thread. As far as I can find, the JK pump and sending unit will also work fine and can extend further.
 
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