Automatic transfer pump

[Irish_Alley]

OK so here's what I'm thinking. I want to do away with the dual fuel tank valve and some how have one tank to supply the engine and the other tank supply the main tank. But you can't just wire up both tanks and "T" all the lines together cause you won't use all that fuel and once it returns there will be no way to regulate which tank it goes into.

One option is to have the main tank feed the engine and the return feed into the secondary one. Then have the secondary one feed the main. If both pumps are the same then it should work but if the main pump is weaker then the main tank should eventually over flow cause it can't keep up with the secondary.

Option B is to have the secondary tank only turn on when the other tank is almost empty. But I'm not sure how to and if it's possible to wire up a ohms switch that's wired into the fuel sending unit.

Option c is to fix it and hope not to have problems with the setup again. But my buddy wants to run dual tanks on his truck that the bed is for a single tank so he can only fill up one side now anyway but he has both tanks.

So my main question is, is there a switch that you can set to a ohm so it kicks on around 10ohms (1/8 tank) and shuts off at 44 (half tank) like a pressure switch for a well can do?

[VileZambonie]

You could do this. My 74 was this way when I bought it. Someone removed the push/pull valve and Tee'd the system with an electric pump. The left tank would feed the right tank when you flipped the switch. If you didn't observe the gauge you could easily overfill the opposing tank. Yes you could operate it on a float switch just like a sump pump but if you are going to do all that, why not just replace the tank switching valve. It's fairly easy

[Irish_Alley]

in my case yes i would be easier to replace the valve but with my buddy he cant fill one of his tanks without modding the bed.

[VileZambonie]

So in that case, what are you going to do, fill the tank with the fill pipe, pump it over to the other tank, then fill it again, then feed from that tank?

[Irish_Alley]

Lol yeah. He was thinking of plumbing a pipe on the bottom of the tanks like Eric Miller did for his Cummins swap. I would like to pull into the big rig pumps and fill both tanks at the same time then just go. And have the truck automatically pull from both tanks somehow. I don't think the fuel line in the bottom of the tanks is the safest or best solution.

[LTZ C20]

I remember going to a gas station and filling both tanks at the same time. You get a lot of funny looks when you have a nozzle going in either side of the truck haha.

[Burkhalter]

I only haveone tank on my rig. I've been thinking about replacing my tool box with one that has a transfer tank built into it. Then having a transfer pump hooked up to a switch in the cab to pump it into the regular tank. How easy would it be to do something like that?

I have considered getting a second tank for the other side and putting a pipe in the bottom of them to connect them. But I'm not all to keen on having a line plumbed into the bottom of my fuel tank just waiting to get ripped off by a large branch or rock.

[werewolfx13]

I don't have any pics, but in the process of a half witted rebuild of my 76 k20, I added a tank to the drivers side, which contains the fuel pump and sender for the 87 tbi engine I dropped in. Not wanting to waste a good 20 gallon tank, I left the original passenger side tank, used an inline electric pump and have a switch in the cluster to turn it on as long as the ignition is hot, and a momentary on/off/on switch (mom on/on would be better) wired to the fuel gauge to monitor the aux tank level.

The filler neck is on the passenger side, it drops into a 1 1/4" x1 1/4 x 1" black iron reducing tee, the 1" nipple BARELY fits inside the filler neck, and I used a silicone sleeve to serve as a sealing boot.

There is a crossover pipe of 1 1/4" black iron pipe that runs between the truck frame and the flatbed frame, which slips inside a factory 1987 filler hose turned toward the passenger side. So while filling, both tanks get fuel, at a very similar rate (smaller inlet on the close tank, large inlet on the far tank). Both tank vents are tied together and to the filler neck.

The crossover pipe may or may not work on a regular bed....