Dual fuel tank filling

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bucket

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Adding sumps to a fuel tank is no big deal. It's been done time and time again. Preferably you start with a new tank, but you can safely weld on a used tank if the proper precautions are taken. I see zero issue with adding a crossover tube, if a shutoff valve is used at both tank outlets.

Another option is to tee the supply lines from the tank to a single electric fuel pump and use a bypass style regulator. Then run the return line back to the tank area and tee it off to each tank. The factory senders will need the return pipe lengthened to reach near the bottom of the tank. Doing this will turn the return line into a siphon tube that balances the level in both tanks. It's simple and effective, and also how GM did it on the '03-'09 medium duty trucks with the optional dual tank.
 

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Adding sumps to a fuel tank is no big deal. It's been done time and time again. Preferably you start with a new tank, but you can safely weld on a used tank if the proper precautions are taken. I see zero issue with adding a crossover tube, if a shutoff valve is used at both tank outlets.

Another option is to tee the supply lines from the tank to a single electric fuel pump and use a bypass style regulator. Then run the return line back to the tank area and tee it off to each tank. The factory senders will need the return pipe lengthened to reach near the bottom of the tank. Doing this will turn the return line into a siphon tube that balances the level in both tanks. It's simple and effective, and also how GM did it on the '03-'09 medium duty trucks with the optional dual tank.
Thankyou :) someone who knows my idea isn't crazy or dangerous and pretty commonly done this way
 

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Welding on a tank put a garden hose in a car tailpipe leave the car running put the other end in the tank. Your tank now is filled with inert gas under pressure. No oxygen no kaboom.
 

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It wouldn't blow up anyway. Has Noone welded a gas tank before?
 

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Back in the day (80's -90's), there used to be a company that marketed the dual tank fill set up like you've shown. I'm sure if you looked in some old Peterson's 4 Wheel and Off Road you'd find adds for this. I can't recall the name of the company.
 

Granias12

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Thank you for the tip MarineOne I have an 87 dual tank set up I was trying to get to where I can fill both tanks at once. I was going to use more rubber line than you did but I like the stainless option. I like the passenger side fill up because in the city almost everyone has driver fill up and all the new gas stations are directional pull in. Especially sam's club which always has the cheapest gas. Since I traded my TBI for carb I installed 2 external pumps into a regulator and have the switches inside to activate the pump. This has helped with theft because you have to throw 3 switches to activate the first pump.
 

Ricko1966

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It wouldn't blow up anyway. Has Noone welded a gas tank before?
I have, but I had a garden hose in the tailpipe of a running car blowng the tank full of inert gas. It was how I learned to do it,and the only way I've done it. How do you do it.
 

MarineOne

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I have, but I had a garden hose in the tailpipe of a running car blowng the tank full of inert gas. It was how I learned to do it,and the only way I've done it. How do you do it.
I just blow it out real well if it had gas recently I will parts wash it and dry it good
 

bucket

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I have, but I had a garden hose in the tailpipe of a running car blowng the tank full of inert gas. It was how I learned to do it,and the only way I've done it. How do you do it.

That's a neat idea.
 

Turbo4whl

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I have, but I had a garden hose in the tailpipe of a running car blowng the tank full of inert gas. It was how I learned to do it,and the only way I've done it. How do you do it.
At work, the welders (body guys) fill the gas tanks with water, then weld them.

I watched one old guy (I was younger then) put the torch over the fill and the tank would go "fum". He did it a few more times until the tank stopped talking and then brazed it empty. Kids, don't try this at home.
 

ballencd

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I want to install a dual tank in my truck but don't like the idea of filling both from one port because I want to be able to carry diesel in one tank and gas in the other. I am about 25 miles from Sams and don't go that way often enough to fill up the cars but I could bring home gas in the second tank and drop it in a storage tank for the cars and then still use it for diesel when on long trips.
 

Ricko1966

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I want to install a dual tank in my truck but don't like the idea of filling both from one port because I want to be able to carry diesel in one tank and gas in the other. I am about 25 miles from Sams and don't go that way often enough to fill up the cars but I could bring home gas in the second tank and drop it in a storage tank for the cars and then still use it for diesel when on long trips.
I don't really like you're idea,but I'll contribute. Install tank 2 just like any other dual tank install with the switching valve and all. Install a ball valve in the line going to tank 2 between the tank and the switching valve.Now put a tee in between the tank and the ball valve. Run the tee to an electric pump with an anti siphon valve and anti bleed back valve. Run the outlet side of the hose somewhere covienent for filling gas cans,etc. Switching valve set on tank 1,close your ball valve turn on your electric pump and pump tank 2 dry. Keep your ball valve closed except when you have diesel in tank 2. For the cost and trouble to save let's a dime a gallon, 20 gallons you saved 2 dollars,if you really want to haul gasoline buy a 55 gallon drum and a barrel pump. You will save 5.50 per trip,less complicated,less investment store your drum in your shed.
 
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ballencd

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Yesterday Sam's was at $2.95.....local station was $3.45.....I'm not sure it's legal to carry a 55 gal drum of gas inside a M1010. I certainly would not want to be in a wreck with one in there.
 

Ricko1966

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Yesterday Sam's was at $2.95.....local station was $3.45.....I'm not sure it's legal to carry a 55 gal drum of gas inside a M1010. I certainly would not want to be in a wreck with one in there.
We used to take 55 gallon drums of VP to the race track,the dunes,wherever we were going. Just a nice slow safe drive home NBD. Go any where where there's a dirt track, count how many 55 gallon drums of race gas on trailers,matter of fact you probably have a local petroleum company that delivers 55 gallon drums of fuel,kero,Stoddard solvent.
 

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