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Box fuel tank

Discussion in 'Engine & Performance' started by Chris H, Jun 30, 2020 at 9:37 PM.

  1. Chris H

    Chris H Junior Member

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    Has anyone converted to just a fuel tank in the box and eliminated the saddle tanks? If so what are the requirements or regulations that you needed to install. Or is it even legal to use a tank like that to gravity feed to fuel pump?
     
  2. AuroraGirl

    AuroraGirl Supporting Member Supporting Member

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    If you have a fuel pump it doesnt need to gravity feed. its still gotta pull the gas upward to the carburetor. is there something not working properly? such as lean or no fuel?
     
  3. gotyourgoat

    gotyourgoat Full Access Member

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    You could get a tank from a 67-72 and start cutting the cab up.

    Afraid of the lies about the saddle tanks?
     
  4. Chris H

    Chris H Junior Member

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    Having trouble getting fuel to carb. I think I may have figured something out. Fuel pump doesn't have return line. May get new fuel pump with return line andbhooknthat back up. May be causing to vapor lock.
     
  5. gotyourgoat

    gotyourgoat Full Access Member

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    So the the lines there still there and the pump was replaced with a non return line pump?
    Sounds like a oe pump would help you out.

    To gravity feed fuel the tank would have to be on a tower a couple feet above the cab. If that would even work.
     
  6. AuroraGirl

    AuroraGirl Supporting Member Supporting Member

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    I dont think pressure from gravity could maintain it at the carb, because it needs pressure which would be constantly varying with percentage
     
  7. Chris H

    Chris H Junior Member

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    Yeah, I just ordered me a replacement pump with the return feed off of it. Gravity feed would be to an electric pump that would be supplying fuel to the carburetor. But this is a lot easier and cheaper way to go if this works, which I think it will. I think it's been Vapor locking because the return system is plugged off.
     
  8. Craig 85

    Craig 85 Full Access Member

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    Check the condition of your rubber fuel lines. Maybe they are soft and collapsing. Remember to check the ones at the tank too.

    IMG_1188 (2).jpg
     
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  9. gotyourgoat

    gotyourgoat Full Access Member

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    Huh?
     
  10. WebMonkey

    WebMonkey Full Access Member

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    the term 'gravity feed' got tossed out there and some were thinking TOTAL gravity feed to the carb and some were understanding gravity out of the fuel tank into a pump and then onto the carb.

    :)
     
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  11. WebMonkey

    WebMonkey Full Access Member

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    en-VEE-us

    sweet!
     
  12. Markmx6

    Markmx6 Member

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    If the vehicle is supposed to have a return line and it is blocked off it will try and pull a vacuum on the tank. You could always leave the gas cap off and see if your problem goes away, just to make sure.

    Funny story though. I used to work for an emissions shop and a camaro came in and it failed on the evaporative system, it wouldn't hold pressure. So another mechanic put a couple BB's in the evap hose by the canister. It fools the test enough to pass and then you pull the BB's out after the test. Anyway, he didn't come back after testing until the car kept running out of gas, but the gauge showed full.

    I put the car on a lift and the tank had collapsed from the vacuum of the electric fuel pump and it wedged the arm for the tank level sensor to the top of the tank making it show full. It only held like 5 gallons of fuel at that point.

    We made a gas cap with a regulator and a compressor fitting and pushed it to about 50 PSI to get the tank back in shape. Luckily that also provided a good leak test and nothing had creased or cracked. Then we pulled the BB's...

    Ok reading that doesn't seem as funny, but it was seeing it...
     
  13. Grit dog

    Grit dog Full Access Member

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    Separate from the mis-construed responses, from my experience it is not legal to have an aftermarket gasoline "transfer" tank that directly feeds the OE tanks or the fuel system directly.
    And there's only a handful of transfer tanks that are DOT rated to haul gasoline. But this is from DOT regs and research years ago, although I doubt the rules are more lax now.

    Best off to fix the issue properly, like you are, IMO.
     

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