Sealing brake bleeder threads

Discussion in 'The Garage' started by ultrachrome, Jul 1, 2013.

  1. Boatman

    Boatman Upward and onward!!

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    Thanks for saying what I was thinking.

    If/when I use tape, I back the bleeder out a couple turns. Then I twist the tape into a thin rope and a wrap around the threads, turn the bleeder in a bit and its sealed.

    Just sayin'.
    #21
  2. ultrachrome

    ultrachrome Poser

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    I attempted to bleed the fronts yesterday and discovered that air being pulled in even when the nipple was closed.

    I tried a zip tie to get a better seal on the hose and when that failed, some safety wire which also proved insufficient.

    I did a manual bleed without vacuum, didn't get any bubbles from the caliper so I called it good for now.
    #22
  3. Bill the Bong

    Bill the Bong Supern00ba

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    I have a Series 2 Land Rover. Only way I could bleed it clean was by using PTFE tape. Only vehicle that I ever had to resolve to doing this. Mostly use a large syringe to force in fluid from the bleeder end for almost anything.
    #23
  4. ultrachrome

    ultrachrome Poser

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    I've got a couple other brakes to bleed, I may try that method as well.
    #24
  5. heart_of_darkness

    heart_of_darkness Adventurer

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    Are the bubbles in the vacuum bleeder always from air, or could they be cavitation?
    #25
  6. JimVonBaden

    JimVonBaden "Cool" Aid!

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    Always air, but sometimes past the threads, and sometimes from the system. You learn to tell the difference.

    Jim :brow
    #26
  7. Stan_R80/7

    Stan_R80/7 Beastly Gnarly

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    The two methods I have had the best luck with are: a.) forcing brake fluid through the system by pressurizing the MC, and b.) opening a bleed screw and letting gravity drain the fluid and any entrained air. Neither technique is especially fast or 'set it and forget it'.

    I have tried (and still have) many types of brake bleeding gadgets from the Mity-vac system, one-way valve bleeder lines, and putting the bleed line in a container with brake fluid. All are fiddly, make a mess, and seem to allow air to get back into the brake lines. I have also put teflon tape on bleed screw threads - but I only have fluid going out of the bleeder screw.

    I wish the money and time I spend on bleeder gadgets was justified. But, it hasn't been. My Mity-Vac is now used more as a hand vacuum pump - but in a pinch it will suck old brake fluid from a MC. Most of the problem I found was getting the bleed screw threads to not draw in air and getting the tubing to stay attached. The principle behind the gadgets is sound but getting tubing slick with brake fluid to stay on the bleed screw nipple and form a seal and air leaking around the bleed screw threads always shows up. But, if another gadget showed up that addressed these issues I would probably buy one - even with a healthy skepticism that it likely won't work.
    #27
  8. mjydrafter

    mjydrafter evil boy for life

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    Just FYI, mity-vac recommends a bit of teflon tape, if you are getting bubbles:

    FAQ #2 here:
    http://www.mityvac.com/pages/info_faq.asp

    Once you have been using the MV for a while, you will skip the tape and know when the bubbles are "right or wrong", as was described earlier in this thread.
    #28
  9. gsweave

    gsweave Yinz, blinkers are on, since 05

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    ultrachome

    Buy some new bleeders and don't over torque em

    No Tape, no grease.

    Never had a bleeder that required more than 3/4 turn to bleed with Mityvac.

    Now grease on the vacuum tube, downstream...I am good with that.


    Teflon tape belongs on water systems not hydraulic systems. It is a poor practice that can and does contaminate...

    http://www.sbp.noaa.gov/resources/engineering/docs/Hydraulic_Systems_Leak_Free.pdf

    Check with any airplane mechanic see how they do it.
    #29