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How To Vacate Bad Gas

Discussion in 'Early CJ5 and CJ6 Tech' started by 1Cerberus4u, Sep 9, 2024.

  1. Sep 9, 2024
    1Cerberus4u

    1Cerberus4u New Member

    New England, USA
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    Sep 9, 2024
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    Hey all, In additon to my non start issue in the prior thread, I do have to deal with old gas in the tank.

    the tank looks like an aftermarket thing as its a squarish box, out back, under the rear. Looks like the lines are on the top of the tank.

    I tried to syphon from the fill but can't get my hose around the 90 degree bend and down into the tank.

    Is it possible to do the old air pressure in a slit after taking the line off by the carb?

    Guessing if so, I should remove the small can gas filter and more importantly will gas flow through and past the mechanical pump?

    Open to other ideas

    Thanks - it will live!
     
    Glenn likes this.
  2. Sep 9, 2024
    Jw60

    Jw60 Well-Known Member 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Trails end,...
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    Remove the top sender or vent and fill with water.

    Then you can add a drain plug somewhere.
     
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  3. Sep 9, 2024
    Glenn

    Glenn Kinda grumpy old man Staff Member

    Apopka, Fl
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    I think dropping the tank would be the wise choice. Then can flush it out good and make sure there isn't crud in the tank.
     
  4. Sep 9, 2024
    1Cerberus4u

    1Cerberus4u New Member

    New England, USA
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    Yea, I was just trying to get it drained enough to get it started.. but I agree, best to drop it
     
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  5. Sep 9, 2024
    1Cerberus4u

    1Cerberus4u New Member

    New England, USA
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    Sep 9, 2024
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    do most of you have or have added drain plugs into your tanks?
     
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  6. Sep 9, 2024
    Jw60

    Jw60 Well-Known Member 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Trails end,...
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    Under seat tanks have stock drains.
    Rear tanks don't have drains but you can pour the tank once dropped out of the frame.

    Can you get a siphon going to drain down to the bottom of the pick-up tube?
     
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  7. Sep 9, 2024
    gromit

    gromit New Member

    harrisburg, pa
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    Nov 6, 2018
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    I've gotta tell you that when I was young and dumber like 50 yrs ago, I needed to get some gas out of one vehicle to pour into my empty tank, a siphon seemed simple enuff. Well, sucking it out thru the immersed hose gave me a mouthful of gas!! Terrible! Later a helpful gentleman gave me the advice to make it close to airtight, wrap a handkerchief around the hose at the donor car's tank filler hole, BLOW into the hose, (you'll hear the bubbles proving you'll get gas), and the pressure will push the gas out easily starting the siphon!! I know many folks here are probably well aware of this, But hopefully it'll help at least one unfortunate out there who may find themselves in a similar needy situation ....
     
  8. Sep 9, 2024
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    Ala Jw60 above - If there are no holes in the lines, you can siphon the fuel from the tank using the existing fuel line to the carburetor. If the line is full of fuel, suggest you take the rubber hose loose from the fuel pump - pinch the line or hold you finger on the end so it does not drain back to the tank. You should have enough hose to lower the line and drain it into a pan. It will be slow.

    You can also take the line loose, add a length of hose and suck on it with a MityVac or similar to start the siphon action. It will take a long time to drain, but it will empty down to the lowest pickup level in the tank.

    You can also start the engine from a gas can on the cowl. Start the siphon and connect to the carburetor. The siphon will be enough pressure to run the engine if the float is not stuck.
     
    Last edited: Sep 9, 2024
  9. Sep 9, 2024
    kenb

    kenb Cleverly disguised as a responsible adult

    Detroit
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    I have a cheap 12v in line electric pump I got on Amazon for about $10. I will connect that to the tank outlet and pump out the tank if I need to drain one.
    Electric Fuel Pump 12v Electric Transfer Universal Low Pressure Gas Diesel Fuel Pump 2.5-4psi HEP-02A https://a.co/d/i1bNzAj
     
  10. Sep 9, 2024
    mtdave

    mtdave New Member

    MONTANA
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    i just went through this on my '65 Mercury, 20 gallon tank with 15 gallons of 30 year old gas, what a stench. i used a Harbor Freight suction pump and pumped it into 5 gallon pails. that was the easy part. Hard part was finding a place to legally dispose of the old gas. A local semi tank cleaning facility took the old gas and added it to their waste tank then "cleaned" the tank. they didn't do a great job, but it was a start. At home i did a vinegar soak of the tank, 50/50 vinegar and water maybe a little stronger on the vinegar. I let it soak for a week then poured it off and rinsed the tank many times with clean water. After a good drying I used Summit's fuel tank sealing and lining kit. so far so good.
    As a side note i did the same thing with the original steel wheels, it took a month for the vinegar to eat through the old paint and rust. With a good pressure wash and a light sanding the wheels painted up beautifully.
     
  11. Sep 9, 2024
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Medford Mass USA
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    I expect the easiest/best way to get rid of old gas is to add it a gallon at a time each time you fill up your daily driver. Dilute it in new gas.
     
  12. Sep 10, 2024
    PeteL

    PeteL If it wasn't for physics, and law enforcement... 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Hills of NH
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    Be very cautious with gas fumes during these operations. A fellow here in town was draining a fuel tank. He triggered his cordless drill several feet away, and it sparked the vapors and set fire to the vehicle.
     
  13. Sep 10, 2024
    1Cerberus4u

    1Cerberus4u New Member

    New England, USA
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    Not sure. I have been unable to get a siphon down the gas fill, that's for sure
     
  14. Sep 10, 2024
    1Cerberus4u

    1Cerberus4u New Member

    New England, USA
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    having lived your experience too, now, I just take a length of hose, put one end in the tank (obviously below serface level), cut a slice a in the hose at the dumb end and use compressed air to "suck/siphon" our the liquid. Works pretty slick
     
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  15. Sep 11, 2024
    vtxtasy

    vtxtasy oldbee 2024 Sponsor 2023 Sponsor

    Tucson, AZ
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    Something to consider when using compressed air around fuel...static. Be careful out there.
     
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  16. Sep 11, 2024
    1Cerberus4u

    1Cerberus4u New Member

    New England, USA
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    Good point, Thanks!
     
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  17. Sep 11, 2024
    Pancho400cid

    Pancho400cid New Member

    Austin, TX
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    I'm a jeep noob, but I did recently have to drain about 18 Gallons of water-contaminated gasoline out of my boat. If you are only dealing with a gallon or two, my method is probably overkill.

    For most of it, I used the simple hand siphon pump - link below:

    https://www.amazon.com/GasTapper-Siphon-Anti-Kink-Jiggler-Retainer/dp/B01M5D2XZQ/ref=sr_1_6?crid=1681X3YSR7LGA&dib=eyJ2IjoiMSJ9.AlEz0KjEUpuJnL7s_5C4MKYwZIKulHQGbapjTHhrKpvaXFngbsdcGWI4UL_HsL3Mcspqh-xk0bKpdbX2DKHhetmcl67_Rh8z-6QQbxkl4KUKxpOgDVM8aDvDwzBOk2pJOd6f_qMtHOyqhah3d9t8_POksaz52kTKrZ131wcWfSgwao4MnRFK-EZn-C0kJm-xpKwGphuR4IRXP5qsYD7r_nEKN9WJSvuYY9RK5YWYpGYlPs7NGqx0y334GQuS1cniDxoY_qz8zNnu3MuJBVb8D9zzYcM0-LtMVXOaS5ijYi4.BuTpcEtTmWsR8F-1EG7wV6j9vTXvxfmNQBCLjLCXJoo&dib_tag=se&keywords=gas+tapper+siphon&qid=1726075445&sprefix=gas+tapper+siphon,aps,120&sr=8-6&th=1

    SAFETY FIRST - Probably beating the obvious but, as mentioned - gasoline WANTS to kill you. I try to remember that one gallon has enough stored energy to move a 4,000 vehicle 20 miles or so, even using a thermodynamically inefficient power conversion. I turned off the water heater pilot near my project because that's what nearly killed a friends father long ago. I bought a hermetically sealed switch for my fuel pump (more below).

    The hand siphon worked great but it was pretty much an all-day project, and well... it's hand powered. I pumped it into a clear 1 gallon jug first. That way you can let it settle a minute or two and physically see what it looks like. Almost all of the gas looked perfectly fine. I then transferred it into 5 gallon gas cans borrowed from a friend who had several. I would let one of my road-worthy vehicles get near empty, then add 5 gallons of the siphoned gas at the station, then top off at the pump. I burned it all with no issues. The last gallon or so was obviously contaminated with water. I gave it to a friend with property for future use as brush-burning fuel.

    I did try an automotive electric fuel pump I had, using a sealed switch. The pump absolutely would not pump fuel if it was drawing ANY air at the inlet hose. Actually the same is true of the hand siphon. Once I'd siphoned off everything I could, I left the tank open for a week and made sure it was bone dry before reassembling everything.
     
    Last edited: Sep 11, 2024
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  18. Sep 11, 2024
    Tralehead

    Tralehead Member

    Silverado, CA
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    Hmmm, I read the title and the first thing I thought was "just open a window"
    o_O
     
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