Troubleshoot HS33 Bleeding

Discussion in 'Observed Trials Discussion' started by Bren85, Mar 21, 2010.

  1. Bren85

    Bren85 Member

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    I have bled my maguras a few times now and seem to be getting the same result. The lever pulls about half way to the bar as it should and locks up. The problem is that it pulls past that point all the way to the bar while locked up. My assumption is that there is air in the system. For reference I have the TPA adjusted all the way to -, and the pads are set close to the rim(set with a cd width). Any tips to solve this would be great. I have been bleeding with a bleed kit and baby oil. While bleeding I have been pumping/flicking the lever to remove any air bubbles and it appears to be getting them out but maybe I am missing some...

    Thanks
     
    Last edited: Mar 21, 2010
  2. bundee80

    bundee80 Member

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    Sounds like either air or you have a leak in one of your seals. Are you feeling any resistance after the pads hit and the lever keeps going; mushy? If the pads retract further than they originally were before you pulled the lever, you've got a leak. If you pull and feel some resistance, most likely air in the system. Gotta go with a water bleed, dawg....FTW!
     

  3. Bren85

    Bren85 Member

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    It's definitely not a leak. I guess I will just keep playing with it. Might try the submerged water bleed tomorrow and see how it works.
     
  4. Dude try my way... I haven't had a problem and it 1000 times cleaner than dumping all your shit is baby oil...
     
  5. perkins

    perkins New Member

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    The kitchen sink works the best. I haven't had a bad bleed yet. I actually have three brakes that I have to bleed tomorrow...
     
  6. Bren85

    Bren85 Member

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    I hate to bring this thread back up but I still have not solved this problem. I tried to the kitchen sink water bleed. I have gone through the process over and over again and keep getting the same result. The pistons move and the levers feels fucking awesome but when I set the brakes they lock up and then the lever pushes past that point. Even with some TPA adjustment it is not rideable. The lines do not have leaks because the brake literally brand new.
     
  7. ateam

    ateam Old Man, Poser, Newbie, "Huba Huba"

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    Come on OTN, help this guy out. I'm thinking it's a bad piston but I'm a newbie. He needs pictures of his complete set up for sure. Make OTN rule MFer's.
     
  8. dannyboy

    dannyboy Active Member

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    im not an expert but iv done a few maggies over the past 15 or so years..

    heres a couple of things to check to help us to help you :)

    1) check all the fittings are tight but not overtightened, iv seen someone overtighten and this led to a leak.
    2) check tpa is all the way out
    3) check that the pistons are fully retracting before you do bleed, if not there can be air in their.
    4) if lever is pulling to the bar - check frame flex, bolts are tight, and that the caliper is firmly held in place by the mounting bolts. Tight but not overtight is the key ;)
    5) THIS IS A GOOD SIGN OF AIR - check that as soon as you pull the lever the pads move at same time, this will only occur if everything is working as its supposed to be and that no air is in the system.
    6) if bleeding with water, flush the system free of oil a few times first or you end up with a mix and this leads to spongey brakes.
    7) check that the seal around the lever (look from end of the handlebar inwards) is not cracked.. this can create a very very slow leak.


    All these things will help us understand what could possibly be going wrong. It sucks your having such dramas and i hope this and other posts help you out.

    Good luck!!

    lastly, if as you say it feels great but when on bike it pulls to the bar, check frame for cracks around seat stays.. this is fairly unlikely but could be the reason why its pulling that far. AS the stays are being pushed out when the brake is on.

    .... keep us posted, danny.
     
  9. bundee80

    bundee80 Member

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    +1 on all of this - especially the bolded points.

    If they're working fine off the bike but not on, sounds like you're tightening the mounts too much. At the lever body, make sure the piston seal isn't leaking.
     
  10. Liviu

    Liviu New Member

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    Hello,
    I had same problem with my front hs33 about 2 months ago.I tried everything,rebleeded(never used water,always mineral oil),but nothing fixed my problem.I pulled out the piston from lever blade,and I noticed for the first time that there on the piston is some kind of second seal(lol:bowrofl: )which protect the sistem against dust and other shits,and I saw that this "seal" is deformed and it lock the piston,as well as you say.I removed that seal,and my brake works properly now.I don't know if I made a mistake,my sistem is not being protected against the dust now,but it doesn't lock,and works smooth.

    *sorry for my english:D
    **I hope u will solve your problem!

    Cheers!
    [​IMG]
     
  11. Bren85

    Bren85 Member

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    Alright. I will go through that list after work and give an update.