In tank fuel pumps and fuel cells

YJJPWrangler

Well-Known Member
Joined
Jul 19, 2005
Location
Charlotte
I'll be moving to a new fuel cell for the willys soon because of clearance issues. TBI 4.3 out of a 1991 S10. Fuel pressure needs to be 10-15psi and a return line. I'm planning on purchasing either the 12g or 15gal RCI tank.


I'll mount it with either a Barnes4wd/Motobuilt etc type hold down.

I would really like to run an in tank style fuel pump as I have had issues in the past with inline fuel pumps.

Main question would be what type of fuel pump should I run? I was thinking a stock GM fuel pump like this


But I am concerned with how it will mount to the RCI tank. It looks like the tank comes with a sending unit for fuel level. What is everyone using?
 
FWIW, the TBI FPR (fuel pressure regulator) will bypass anything above where it's set (10-15psi) so about any in-tank FI pump would be fine...

The bigger issue will be mounting the pump in any of the RCI cells. RCI does offer an "in-tank" flange/hanger (replaces the existing "fill plate" (adding new supply/return bungs), but IIRC, aren't long enough to reach the bottom of these tanks *without mods* 🙄


I was going to swap to in-tank just to clean things up, BUT have had zero issues feeding the TBI (15# previously on the 304) with a $20 fleabay "E2000" or the Sniper (60# on the "new" 360) with a Walbro GSL392... both inline pumps
 
@Caver Dave thats what I was thinking as well. I can utilize my existing inline fuel pump for now and can always replace it as needed. My current tank has no pickup, its gravity fed. With the new RCI tank, I just should be able to hook my fuel pump to the supply hose/pickup and be fine.
 
@Caver Dave thats what I was thinking as well. I can utilize my existing inline fuel pump for now and can always replace it as needed. My current tank has no pickup, its gravity fed. With the new RCI tank, I just should be able to hook my fuel pump to the supply hose/pickup and be fine.
You will burn pumps in my experience.
 
@Caver Dave thats what I was thinking as well. I can utilize my existing inline fuel pump for now and can always replace it as needed. My current tank has no pickup, its gravity fed. With the new RCI tank, I just should be able to hook my fuel pump to the supply hose/pickup and be fine.
FWIW this is how I ran the new pump on my C10. XJ gas tank with an inline pump sitting on the tank. It pulls through the stock xj pump. Runs fine, we will see how long it lasts.
 
Rci sells (about $120) a retrofit in tank hanger that replaces your 12 bolt filler, it comes without a pump, put a tbi in tank pump in it with fuel exposure rated hose to the outlet and dont worry about it again. I've got a lot of expensive external pumps that are all on the shelf for eternity now, not only noisy but almost guaranteed to die after a few years.
 
I'm a fan of the goatbuilt tanks that use the newer gm truck fuel pump module. It is readily available and has a built in "sump". Its more pressure than you need but it'll just bypass back to the tank. Plus the tank is plastic so no worries about cracking or expensive mounts.

 
I probably did this the hard way, but I'm happy with how it turned out. RCI 1212C 22gal bladder cell because it fits mint in a TJ. Goatbuilt hanger for a GM pump. Cheap GM pump assembly from an Avalanche or something. I used Amazon and returned 2 pumps before I found on with the correct depth. I'll use a WJ fuel pressure regulator outside the tank to get the correct pressure for my 2.4, then remove the external reg when I LS swap it.

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In my hot rod, I have a Tanks Inc hanger with a Walbro grafted into the top of a stock replacement steel tank. They have some other options. Tanks Inc
 
Nothing to add about in the tank pump, but... I'd choose a different tank. I know of and had personal experience, unless they've stepped up their game, the RCI tanks are destined to fail. they split at the fused seams. Our group had 4 to fail on a trail ride to golden mountain several years back. I hope your mileage varies.
 
You will burn pumps in my experience.
Maybe mines the exception, but in 15 years never lost a pump, but took the advice of several folks (like @R Q) and put a filter BEFORE the pump.
I believe @uglyjeepoffroad has had issues feeding his 5.2L goat motor though? 😁
Nothing to add about in the tank pump, but... I'd choose a different tank. I know of and had personal experience, unless they've stepped up their game, the RCI tanks are destined to fail. they split at the fused seams. Our group had 4 to fail on a trail ride to golden mountain several years back. I hope your mileage varies.
Chip, were any of those using cradles?
The only first hand knowledge I have of split seams, has come from folks either bolting them down (thru the weak flanges 🙄) or questionable strapping (very narrow/no rubber insulation)...

Mine came from @snappy . IIRC, a direction change when building his ECORS rig, so 10+ years old?
 
Maybe mines the exception, but in 15 years never lost a pump, but took the advice of several folks (like @R Q) and put a filter BEFORE the pump.
I believe @uglyjeepoffroad has had issues feeding his 5.2L goat motor though? 😁

Chip, were any of those using cradles?
The only first hand knowledge I have of split seams, has come from folks either bolting them down (thru the weak flanges 🙄) or questionable strapping (very narrow/no rubber insulation)...

Mine came from @snappy . IIRC, a direction change when building his ECORS rig, so 10+ years old?

We have run several fuel pumps like that. Never much issue out of them. Just change the filter when it starts looking rough and roll on.
 
Maybe mines the exception, but in 15 years never lost a pump, but took the advice of several folks (like @R Q) and put a filter BEFORE the pump.
I believe @uglyjeepoffroad has had issues feeding his 5.2L goat motor though? 😁

Chip, were any of those using cradles?
The only first hand knowledge I have of split seams, has come from folks either bolting them down (thru the weak flanges 🙄) or questionable strapping (very narrow/no rubber insulation)...

Mine came from @snappy . IIRC, a direction change when building his ECORS rig, so 10+ years old?
On my Samurai, I ran a filter for a 5.0 Mustang (I think) then into an E2000 pump strapped to a crossmember. I wheeled and drove it on the road like that for 10 years.
 
Nothing to add about in the tank pump, but... I'd choose a different tank. I know of and had personal experience, unless they've stepped up their game, the RCI tanks are destined to fail. they split at the fused seams. Our group had 4 to fail on a trail ride to golden mountain several years back. I hope your mileage varies.

Yup, I read through that thread a few nights ago. Since that time period, I haven't read any other issues regarding the cells.

I think the direction I'm going to go in is RCI tank, a cradle, then a GM in tank pump. The regulator on the TBI won't care what pump it uses because anything over the required amount will be sent back to the tank. I do have a working inline pump so I could potentially use that while waiting for parts.
 
😁

Chip, were any of those using cradles?
The only first hand knowledge I have of split seams, has come from folks either bolting them down (thru the weak flanges 🙄) or questionable strapping (very narrow/no rubber insulation)...

Mine came from @snappy . IIRC, a direction change when building his ECORS rig, so 10+ years old?
biggest issue with those tanks was people would run them with foam or baffles and the fuel running from side to side was a huge issue.
 
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The four tanks that leaked were all mounted a little different, but with some similarities. I can't remember how all were mounted, but I do remember how mine was mounted. Mine was resting on a rubber base, with two straps across, and to the floor of the Jeep. The straps were insulated with rubber also.
After much thought I think the issue was fuel surge and too thin of metal. @mcuttler may remember more as Matt had one of the tanks that failed.
I will say that RCI did warranty all of our tanks. All but one of us chose their steel cased bladder tanks, the fourth of us chose the same tank but what they refered to as "double welded" and that tank also failed. That they called double welded, IMO wasn't double welded, it just had filler rod used instead of just fusing the welds. The steel tanks with the plastic bladder did it's job, but didn't hold up well if it sat outside or got wet. as it would hold water and as mine did, the steel was almost fused to the plastic with rust. I had to cut it out of it's can. I still have the bladder that I use on my trailer to be my fuel for my Generator.
 
I’ve been looking pretty heavily into the Motobilt fuel cell/mount package. Specifically this one.


It’s sized correctly and would fit nicely. However it’s only setup for a TJ pump. TJ pumps push around 40psi and my 4.3 only requires 12-15(at the most). The way I understand it, the 4.3 tbi fuel regulator will send all that unwanted psi/gas back to the tank via the return. I’m concerned that the psi will be too much and will eventually blow the regulator out/ injectors etc. I found some old threads on another forum talking about issues with the regulator going bad or injectors blowing due to too much pressure.

So, would too much pressure be a bad thing? Should I just run it with a TJ pump and not worry about it? Or is there a way to adapt the correct GM pump to a TJ unit?

TJ unit


GM pump



Or could I put together a bastard pump that uses the TJ unit but with a GM pump attached?
 
If you can get the TJ sending unit, you should be able to swap the pump for a different submersible one with lower pressure.

Another option would be to run another regulator/filter before the tbi regulator to reduce the pressure.
 
Too much pressure. I had the issue.

That's kind of what I was thinking as well. Thank's for the input on your experience.
If you can get the TJ sending unit, you should be able to swap the pump for a different submersible one with lower pressure.

Another option would be to run another regulator/filter before the tbi regulator to reduce the pressure.

This was my line of thinking. Get the TJ unit, replace pump with the correct PSI GM one and be done with it.
 
On the LS swap I did on my dump truck..I put a higher pressure pump in the TBI sending unit. Those TBI pumps are small and would be easy to retrofit into a different assembly….
 
Well, I helped a friend with a 4.3 tbi swapped from an early S10 and couldn't understand why it was running so bad. Mega rich with no reason. Blowing regulators after regulators.

Ended up realizing that the Walbro 255lph he was using was way too much of a pump for the regulator.
Added a second inline regulator set at 20 psi (IIRC) and it solved all the issues.

That's my experience.
 
I made a mounting ring to run a universal pump in the Motobilt spot it was $8 in aluminum cut to the right od from Etsy

The Motobuilt cradle seems overkill, and the welds are nice. Plus the vent with rollover ball should prevent pressure buildup from too high pump volume. Honestly I would just run the tj pump to an external regulator if you have a tj, or use a universal pump
 

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