Avid Juicy 5 frustration

clanton
clanton Posts: 1,289
edited June 2009 in MTB workshop & tech
My sister was trying to change the brake pads on her Juicy fives and struggling so I went over to help her.
The initial problem was the we couldn't get the pisotns pushed back into the caliper far enough to get new pads in. The pistons themselves looked a little damaged, I cleaned them with IPA and then lubed them lightly with a Teflon based spray but to no avail - putting a lot of force in initially tih a plastic tyre lever then with a 10mm ring spanner. In desperation I then opened the bleed port at the lever, some fluid came out but pistons wouldn't shift! Eventually I got the old pads back in and then with the bleed port back, tapped a scrwdriver between them, after doing this a few times from various angles the pistons were back and newd pads went in fine.

However now a new problem, brakes not gripping well! Figuring we'd lost too much fluid I decided to bleed the brakes. I got it set up as per the Park tools instructions (I've bled the other halfs before on 2 occasions just fine), sucked from the caliper initially, then released lever and tried to push some fluid through to the other syringe at the lever but no joy, wouldn't shift a mm. Eventually the damn tubing popped off the syring spraying DOT oil all over the place and almost certainly trashing the new pads! I tried sucking from the lever syringe, pumping the brake lever (the caliper syringe moves out and back in response) But I can't bleed the damn thing! The only thing I can think of is a blockage in the pipe? What to do next?

Also, how can i tell if the pads were in fact contaminated?

Comments

  • nicklouse
    nicklouse Posts: 50,675
    have you read the AVID how to bleed your Avid brakes?

    Or watched the video in the sticky above?

    you do have the avid bleed kit?

    they are very easy brakes to bleed with the right kit.

    but it does sound like the pistons need a good clean as well.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • clanton
    clanton Posts: 1,289
    Hi Nick
    Not watched the video but have printed off two different step by step instruction "manuals" and successfully follwed them before. I double checked myself and I think I'm doing everything right, there's no clamps clamped etc. I have the Formula bleed kit rather than the Avid one but they're very similar and has worked fine before.

    Pistons wise I gave them a pretty good squirt with IPA and then took a toothbrush and a clean cloth to them.
  • tmg
    tmg Posts: 651
    If you have the bleed kit from Avid you can't go wrong if you follow the instructions

    It tells you to remove the pads (so they don't get contaminated) and has a very convenient plastic block to stick in where the pads once where to stop the pistons from returning. If you can get the plastic block in then the pistons have returned far enough, so disc brake cleaner or IPA and a tooth brush should clean em out
  • clanton
    clanton Posts: 1,289
    Thanks for the reply. I took a lot of care to follow the instructions to the letter and I'm quite sure I've done noting wrong, nor do I think the problem lies with the bleed kit.
  • tmg
    tmg Posts: 651
    Well if you think its a blocked hose then suggest you buy a new one and get the instructions from Avid website on how to set it all up from scratch

    Have to say tho from your description of what you were doing whilst bleeding sounds very different to the procedure I followed yesterday to bleed mine and mine work perfectly now, but I could be reading things wrong from your post.

    Good luck with it
  • sniper68
    sniper68 Posts: 2,910
    Is there fluid in there?You may have lost most of it.Fill a syringe with fluid the push most of it to the top syringe with the lever in its normal position(not tied back)Then start the bleed proceedure..
    Have you made sure the lever reach adjustment grub screw is screw out 2-3mm.Avids won't bleed if its screwed in.
  • clanton
    clanton Posts: 1,289
    ibbo68 wrote:
    Is there fluid in there?You may have lost most of it.Fill a syringe with fluid the push most of it to the top syringe with the lever in its normal position(not tied back)Then start the bleed proceedure..

    No fluid will go in, whether lever is pulled to the bar or released.

    ibbo68 wrote:
    Have you made sure the lever reach adjustment grub screw is screw out 2-3mm.Avids won't bleed if its screwed in.

    Didn't check that - thanks. Might be the issue!