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Discussion Starter · #1 ·
What are most of you guys doing for fuel tanks? I'm relocating mine so my options abound. Would I be better going with a carb-style tank? What modifications would I need to do to make it compatible to a diesel type draw system? For size I'm actually inclined to go with an S10 22 gallon tank. It'll fit perfectly between the frame rails. It's FI though and I'm sure that's more involved. Thoughts?
 

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Just remove the fuel pump from a FI tank and add a tube that reaches the bottom and you are done. Easy.
 

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Discussion Starter · #3 ·
Should it be copper for conductivity-sake? Also, should it go right TO the bottom or should it hover about a 1/2" or so (I know diesels have issues with dredging tanks).
 

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Should it be copper for conductivity-sake? Also, should it go right TO the bottom or should it hover about a 1/2" or so (I know diesels have issues with dredging tanks).
Hi, I am not sure why it should conduct. I will be making a new pickup for mine and I am just going to get 10mm or preferably 12mm stainless tube and get it tigged to a flange . I will attach it via 12mm 90' compression fitting to nylon fuel line. I would got to the bottom of tank but notch it slightly so it can't get blocked if it sucked on the bottom of the tank.

Gaza
 

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I've done 2 already and done the same as Linctex. I would just recommend putting an inline filter if you remove the pump/screen assembly.
 

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Dont forget the return line from the VE Pump to tank. The return line must go to the bottom of the tank.

Paul
Why the bottom? I was going to plumb mine to the vent line (in the top of the tank)
Thanks,
Mikel
 

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You want the return to be as far from the intake as possible and at the bottom of the tank to avoid aeration of the diesel fuel. Diesel will hold a significant amount of air if it's bubbled / shaken up..
 

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You want the return to be as far from the intake as possible and at the bottom of the tank to avoid aeration of the diesel fuel. Diesel will hold a significant amount of air if it's bubbled / shaken up..
Thanks. My J300's fuel tank doesn't have a proper return line. Any reason why I can't tap into the fuel inlet line near the tank and have the returned fuel dump into the inlet isolated from ambient air?
 

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Thanks. My J300's fuel tank doesn't have a proper return line. Any reason why I can't tap into the fuel inlet line near the tank and have the returned fuel dump into the inlet isolated from ambient air?
If you're talking about doing a T into the line coming out of the tank and going to the engine.. Remember that the fuel does 2 jobs in the IP: Lube and cooling. However you do it, you probably want to cycle the fuel through the tank to avoid potential overheating. Plus, the return fuel is somewhat aerated to start with, so it needs to be able to "settle" a bit.
 

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If you're talking about doing a T into the line coming out of the tank and going to the engine.. Remember that the fuel does 2 jobs in the IP: Lube and cooling. However you do it, you probably want to cycle the fuel through the tank to avoid potential overheating. Plus, the return fuel is somewhat aerated to start with, so it needs to be able to "settle" a bit.
I think I'll graft a return line downpipe into my original fuel level sender/pick-up assembly. Thanks.
 

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The return line needs to be submerged to help avoid problems with the pump loosing it's prime, and then being hard to start.

As mentioned the fuel will help cool the pump, so you want to draw fresh fuel from the tank, No T fittings in the suction line

I don't believe it's necessary for the suction and return to be at opposite ends of the tank, but you don't want them side by side, and if they happen to be, point them in different directions.

Grigg
 

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My return line dumps into the vent side of the fuel filler tube.

Meaning....there are two steel tubes between the gas cap and the tank: one to fill the tank (about 1-1/2") and the other a vent (about 5/8") when filling.

My return dumps into the vent tube. It was easier to do that than drop the tank and mess with the sending unit part.
 

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Both of those probably are far enough away from the pickup part of things to allow the fuel to de-aerate..
 

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Discussion Starter · #16 ·
Good to know. Thanks a lot for the info guys!

As for the pickup tube - stainless and about 3/8" from the bottom? Any specific diameter better than another?
 

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Most often the return is one size smaller than the suction.
It would not hurt if they were the same size.


Grigg
 

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Both of those probably are far enough away from the pickup part of things to allow the fuel to de-aerate..
Right, the main reason to keep the return line all the way to the bottom, as specified in the Cummins Shop manual is to;

Keep it from areateong /foaming when returning fuel to less than a full tank. Keep the pickup far as possible from the return and you should not have problems, you dont want to pickup fuel that has air bubbles in it/foam from the return line

Paul
 

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As for the pickup tube - stainless and about 3/8" from the bottom? Any specific diameter better than another?

Not really......since most efi pumps have a 5/16" (8mm) nipple where they have the hose clamp onto them, I have always just used the same size tube.

Just notch the bottom like this -> l / \ l
and you can get closer to the bottom of the tank.
 

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Right, the main reason to keep the return line all the way to the bottom, as specified in the Cummins Shop manual is to;

Keep it from areateong /foaming when returning fuel to less than a full tank. Keep the pickup far as possible from the return and you should not have problems, you dont want to pickup fuel that has air bubbles in it/foam from the return line

Paul
Thanks for this info Paul. This is all new to me. When I install my new pickup I will use my old pick up as the return as the one thats there now only goes in about 1" so will be aerating when it falls into tank.
I have clear lines and when looking with a light behind them the flow to the pump appears stationary as it is clear where as the return appears to have something in it and can be seen moving, at a fair old lick I might add even just ticking over. This I assumed must be air (what else could it be) and I thought I must have an air leak but failed to stop it even though I replace all copper washers in the system. I have now concluded that it must be aerated in the pump, but how? and where does the air come from?

Gaza
 
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