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Aux tank under the bed - help to connection

Renaton

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Hi!
I'm designing an aux tank to mount under the bed. I want delete the spare tire and replace it with the new tank.
Now, to finish the project I've only the problem about how I can connect it to the main fuel tank.
The top solution is to connect directly to the engine (like Long Range that I have in the H100 Toyota) but I've seen that all the aux tank producer make them with a trasfering of fuel from the aux to the main. So I think that the direct solution is impossible.

So, is there anyone that have a diagram on how the aux tank (like long range for 3.6 or similar) is connected to the main tank for its refill? Or anyone that can give me any suggestion?

Thanks to all!
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Main Line Willys

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I would drop a suction line into the new tank and run the line to the fill neck on the oem.

Use a switch controlled inline fuel pump.

If possible, and I am assuming it is, remove the exiting fuel neck and braze in a nipple to accept the new line.
 

BlueScapegoat

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I'll spend stupid money for a second or extended tank for the EcoD. That's all I have to add.
 
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fourfa

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Tagged for interest. I’ve been using a dumb simple Titan Sidekick with a battery-powered stick pump to transfer. But I’m switching to a Moeller under-deck marine HDPE tank in the bed (with my camper setup I happen to have an orphaned space in the bed that’s hard to reach, and this tank fits there perfectly)

The typical setup with these tanks is a rigid withdrawal tube with a pickup that reaches the bottom of the tank, a fill neck designed for a fill hose and hose clamps, and a threaded vent fitting (for air to enter as you pump fuel out, and escape as you fill the tank). Usually you’d fit an electric pump to the withdraw line, and plumb it to an insert in the factory fuel tank fill hose. RDS makes a number of different sized inserts for instance. My plan is to figure out which RDS insert fits the stock filler, and run the withdraw and vent lines to it. Then put the electric pump on a switch only reachable while parked and standing next to the tank, so I can listen carefully and not overfill the stock tank :) Since the aux tank is bigger than the main, and the whole point is to reduce mess/spill/smell
 

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BuckeyeButch

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for decades I've just used an outboard fuel line with a bulb primer to syphon the fuel from my auxiliary tank to my main tank.
 

Jaxmax

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Tagged for interest. I’ve been using a dumb simple Titan Sidekick with a battery-powered stick pump to transfer. But I’m switching to a Moeller under-deck marine HDPE tank in the bed (with my camper setup I happen to have an orphaned space in the bed that’s hard to reach, and this tank fits there perfectly)

The typical setup with these tanks is a rigid withdrawal tube with a pickup that reaches the bottom of the tank, a fill neck designed for a fill hose and hose clamps, and a threaded vent fitting (for air to enter as you pump fuel out, and escape as you fill the tank). Usually you’d fit an electric pump to the withdraw line, and plumb it to an insert in the factory fuel tank fill hose. RDS makes a number of different sized inserts for instance. My plan is to figure out which RDS insert fits the stock filler, and run the withdraw and vent lines to it. Then put the electric pump on a switch only reachable while parked and standing next to the tank, so I can listen carefully and not overfill the stock tank :) Since the aux tank is bigger than the main, and the whole point is to reduce mess/spill/smell
Why not put the switch on dash somewhere and when you want to transfer on a level spot , watch your main tank gauge and fill it to say 3/4 or so.
I'm old if I was standing next to the truck and women came up to talk to me (happens all the time), I would end up standing in a puddle of gas!......Jack
 

TheSolarWizard

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I'll spend stupid money for a second or extended tank for the EcoD. That's all I have to add.


there's already one developed. hold's 25 gallons. Im running it as a primary if you want one all ya gotta do is ask lol
 

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Renaton

Renaton

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The typical setup with these tanks is a rigid withdrawal tube with a pickup that reaches the bottom of the tank, a fill neck designed for a fill hose and hose clamps, and a threaded vent fitting (for air to enter as you pump fuel out, and escape as you fill the tank). Usually you’d fit an electric pump to the withdraw line, and plumb it to an insert in the factory fuel tank fill hose. RDS makes a number of different sized inserts for instance. My plan is to figure out which RDS insert fits the stock filler, and run the withdraw and vent lines to it. Then put the electric pump on a switch only reachable while parked and standing next to the tank, so I can listen carefully and not overfill the stock tank :) Since the aux tank is bigger than the main, and the whole point is to reduce mess/spill/smell
Yes! This is a solution that I have tought. An aux tank from nautical field or homemade adapted under the bed.
The transfer in the factory neck is the simplest solution. But when I have seen the model like Long Range that is connected to the factory tank return pipe, I had several doubts. But now I think that this is a solution for the position of their aux tank.
I think to connect all the indicators and controls near the driver position.
Thank you for info about RDS insert.
 
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Renaton

Renaton

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there's already one developed. hold's 25 gallons. Im running it as a primary if you want one all ya gotta do is ask lol
I looked everywhere before deciding to get it done. What would this be?
 

ScoutVet19D

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there's already one developed. hold's 25 gallons. Im running it as a primary if you want one all ya gotta do is ask lol
I'm curious, and once again I looked at your build thread and remembered none of my builds could touch a rich mans Savvy special. Closest I've gotten was Blaine offering me advice on hydro steering on the old Jeepforum. Can't imagine getting his shop to custom build one.

So is the one in yours now available aftermarket or still in development? Getting ready to tow my 23 ft camper with my gas guzzler and would be nice to have more range.
 

TheSolarWizard

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Development is finished.
Official pricing due out 6/1 but if you’re willing to be a little flexible in final purchase price there’s a queue forming. ~ 65 orders in already
 

Main Line Willys

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@TheSolarWizard is this tank diesel only or will it be gas certified as well?
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