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routing fuel line along the frame

Discussion in 'Early CJ5 and CJ6 Tech' started by ziv, Sep 13, 2010.

  1. Sep 13, 2010
    ziv

    ziv Member

    Israel
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    Hello.

    My CJ-5 has under seat tank, boxed frame and the F134 engine.
    The metal fuel line goes right out from the tank - along the right (passenger side) frame - front to under the radiator - left and back to meet the fuel pump.
    I have a problem attaching that metal line to the boxed right frame. Is there any "original" way to do it? or some good ideas?

    Ziv
     
  2. Sep 13, 2010
    Posimoto

    Posimoto Hopeless JEEP Addict

    Minden, Nevada
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  3. Sep 13, 2010
    ziv

    ziv Member

    Israel
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    wow. never seen that kind of hi-tec clamps.

    1. I wonder what was the original way to attach and secure the fuel line to the frame.
    2. Look at my post (above) about that routing. Is it the original routing for the F134 engines?

    Thanks
    Ziv
     
  4. Sep 13, 2010
    jpflat2a

    jpflat2a what's that noise?

    Hermosa, SD
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    Ziv
    I would think the fuel line should have been run along the drivers side of the frame.
    The original clamps were just a fold over inexpensive metal clamp, no insulation (or maybe some type of cloth). I am using the insulated type to hold to the frame to prevent rub thu of the metal line.
    probably an "insulated closed clip" might be a better description.
    some are just vinyl coated, but the ones I used have a real soft rubber insert.
     
    Last edited: Sep 13, 2010
  5. Sep 14, 2010
    colojeepguy

    colojeepguy Colorado Springs

    At the foot of...
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    Do a google search for "adel clamps". That's what you need to hold the line in place.
     
  6. Sep 14, 2010
    duffer

    duffer Rodent Power

    Bozeman, MT
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  7. Oct 8, 2010
    ziv

    ziv Member

    Israel
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  8. Oct 8, 2010
    Walt Couch

    Walt Couch sidehill Cordele, Ga. 2024 Sponsor 2023 Sponsor 2022 Sponsor

    cordele, Ga.
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    I don't have that part on my CJ5A. Was it possibly for a second fuel tank at one time? That's the only reason I could think of for it being there unless it was for a separate drain.
     
  9. Oct 8, 2010
    Philip-TX

    Philip-TX Member

    Flower Mound, Tx
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    ?fuel shut-off valve maybe?
     
  10. Oct 8, 2010
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    It's plumbed with copper, so it's not original. Copper is not used for fuel lines because it will fatigue and crack from the any flexing or vibration. Steel only.

    Since it's not original, it could be what the PO had on hand in place of a proper union.

    I would not put it back. Use a single piece of steel line as much as possible. If you need to join two steel lines, use double flares and a proper union. Alternately, short lengths of high-quality rubber hose are ok, as long as they are accessible for service. But all-steel is better.
     
    Last edited: Oct 8, 2010
  11. Oct 9, 2010
    ziv

    ziv Member

    Israel
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    As far as i know all 5's here have that part (dont know how to name it). Its just in the place where the line from the fuel tank meet the line that goes to the fuel pump. The line that goes to the fuel pump has a "fuel switch" which is a good idea anyway (I can post pic. if interesting).
    All fuel lines are made of copper. That the way they built them here... Brake lines are steel.

    Ziv
     
  12. Oct 9, 2010
    MA74CJ5

    MA74CJ5 Member

    Bolton, MA
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    I can't speak for the part in question but I am almost certain that all Jeep vehicles had steel lines and not copper. I have never seen a copper line on any Jeep. Jeep used steel along the frame with rubber lines on the ends. The only other fuel line used was a hard nylon line for the fuel ventilation systems.
     
  13. Oct 9, 2010
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    Steel has much better structural properties than copper. Steel will not fatigue under repeated minor flexing, as long as the flexing remains under the so-called fatigue threshold. Other metals, like copper and aluminum, do not have a stress threshold. For these metals, the fatigue accumulates, and the metal eventually fails, no matter how small the stresses are. This is why aluminum airframes must be retired after a finite number of pressurization cycles. Regardless of how strong you make the fuselage, it will fracture eventually. A copper fuel line will crack, eventually, just from the minor movements from driving and being rigidly attached.

    Here's a graph from a textbook that I picked from a course presentation at CMU:

    [​IMG]

    You can see the effect - below some stress limit, the number of cycles to failure becomes infinite for steel. Not so for copper - it will eventually break.

    Sorry to be so wordy about this - but I do know what I'm talking about wrt this topic.

    I have only seen copper used for fuel lines in very old cars (ie 1920s models) and as a shade tree repair. Maybe they operate under different rules in Israel, and there's some motivation for using copper, but it's both more expensive and an inferior material for this application.
     
    Last edited: Oct 9, 2010
    Mike Spicer likes this.
  14. Oct 9, 2010
    DREDnot

    DREDnot Not new to JEEPS

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    Does that drain seem to be in the low spot of the system?

    It may be a military retrofit for long term storage.
     
  15. Oct 11, 2010
    ziv

    ziv Member

    Israel
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    timgr - I realy dont know why they used copper for those lines. However, about the "fuel switch" that i described earlier this post - do you find it on your jeeps?
    DREDnot - that is what im thinking also. They cut the line in 2 places: in one they put that part and in the other they put that "fuel switch".
    Ziv
     
    Last edited: Oct 11, 2010
  16. Oct 11, 2010
    1960willyscj5

    1960willyscj5 Well-Known Member

    Mesa, Arizona
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    Looks like a T-fitting to me. :tea:
    Is there evidence of a second tank, maybe in the rear?
    Or maybe a generator mounted in the rear passenger/cargo area?:hurrican:
     
  17. Oct 11, 2010
    1960willyscj5

    1960willyscj5 Well-Known Member

    Mesa, Arizona
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    Oh, yeah

    The fuel line runs from the bottom of the tank over to the Drivers side frame rail and forward to the vicinity of the pump.
    It is one of the things in the way when you work on the original brake master cylinders.:tea:
     
  18. Oct 12, 2010
    ziv

    ziv Member

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    No evidence for second tank or generator in those jeeps.
    Ziv
     
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