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  1. #1
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    Nasty fluid and debris in Codes?

    Just did a fluid flush and bleed, well I tried to flush the old fluid out, and what old fluid I could get out of the system had a blackish tinge. More disturbing was the presence of tiny black chunks of what looks like rubber from the seals. After I was able to purge some of the old fluid out by pushing the new from caliper to reservoir, the line felt like it became plugged up and I wasn't able to push any more new fluid through the system. Has this happened to anyone else? Are my lines clogged with debris? What could have caused this?

    I'm going to order a rebuild kit and some new hose, but in the meantime I'd love to hear any advice or similar experiences.

  2. #2
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    I just rebuilt the calipers in my Juicy7's. Lots of black debris and dirty fluid. When I took the piston seals out they were falling apart. A big slice was hanging in the back of the caliper behind the piston. Not sure about why you can't push fluid through.

    Good luck

  3. #3
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    I had one set like that. I just flushed it thoroughly and it was fine. Subsequent bleeds did not show any more dark fluid.

  4. #4
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    Thanks. I just did a rebuild on my Juicy 7's and the fluid was a little dirty, but nothing like the Codes. The pistons & seals were in pretty good shape too, though one piston was sticking pre-rebuild.

    I forgot to add that when drawing a vacuum at the reservoir I kept sucking air bubbles syringe after syringe (we're talking 6 or 7 full syringes of air). I must have seal and o-ring damage because air is getting into the system from somewhere. No signs of fluid leakage though.

  5. #5
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    Quote Originally Posted by XSL_WiLL
    I had one set like that. I just flushed it thoroughly and it was fine. Subsequent bleeds did not show any more dark fluid.
    Were your lines clogged? I can not push any more fluid through not matter how hard I push on the syringe. Both front and rear lines.

  6. #6
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    Have you tried pumping the brake lever with the caliper syringe still attached? You'll get more force from the lever than by pushing a syringe plunger - hopefully this will force/flush any bits of seal out of the hose. You'll have to top up the reservoir in the lever I imagine. You'll also probably need to take your caliper apart and clean it out afterwards though :-( Keep a light vacuum on the caliper syringe as you do this to prevent fluid being sucked back into the caliper/hose from the caliper end when you let go of the lever.

    Other option is to disconnect the hose from the caliper and do the same i.e. force sh1t loads of fluid through the hose by squeezing the lever and keeping the lever reservoir topped up with fluid (leave the lever syringe connected as when you squeeze the lever the timing port closes and the fluid can only be pushed down the hose, not back into the reservoir). You'll have to block the end of the hose somehow when you let go of the lever, otherwise it'll simply suck air back into the bottom of the hose.

    Taking the whole system apart is pretty easy and you can clean/grease (brake grease!) the piston seals at the same time.

    I serviced my K24s recently and the 6month old fluid was black - bit worrying really!

    Also - don;t pull too hard on the caliper syringe as it simply sucks air past the caliper seals.

    Sorry if this is a bit rambling - quite early here in the UK!

  7. #7
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    Quote Originally Posted by AndyN
    Were your lines clogged? I can not push any more fluid through not matter how hard I push on the syringe. Both front and rear lines.
    The lever isn't being pulled, is it?

    Make sure the knob isn't set to either extreme of its adjustment.

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