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Avid juicy 3s leaking juice...

crazycamcrazycam Posts: 13
edited March 2009 in MTB workshop & tech
Easy all,

Having a few issues with my brakes. Went to go for a ride the other day, first one since the before the cold spell. Tried to wheel the bike out of the garage (unheated) and both discs were locked up. Had never come across this before and squeezed both levers to try and free them up causing fluid to escape from between the seals on the oil sump. This freed up the jam but is obviously not right.

The oil has expanded for some reason, which I can only imagine was caused by the bike being stored outside in the cold. The seals seem to have been permanently effected as they now leak when the levers are fully compressed even though the temperature has dropped.

The brakes themselves are still working fine. I risked it and took it out for a decent x c ride but am concerned about the leak.

Any suggestions as to what the problem could be and how to prevent it happening in the future? I am supposing the seals have gone and will need to be replaced? The amount of oil lost is not great but will this need to be replaced too? Is this a job a novice could carry out?!

Any help would be appreciated.



  • nicklousenicklouse Posts: 81,520 Lives Here
    it could just be some residual oil that has now decided to move off the top of the diaphragm.

    how much oil has it now stopped?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • It still happens when the levers are compressed in a stationary position. Haven't taken it out again since the time mention. The amount of oil expelled is only a dribble each time. If like you say it is excess oil should I keep compressing the levers and see if the amount reduces with time?

    Its never happened before so I am supposing its the seals. Why would the brakes have locked up in the first place?
  • Done a little bit of searching and have found a few reports of Avid juicys leaking due to being susceptable to corrosion in the top caps. Apparently the top caps supplied as standard are uncoated and once corroded allow oil to leak through the seals. The thing to do is get hold of coated alloy top caps.

    Has anybody heard of or had a similar problem?
  • :(
  • IngieukIngieuk Posts: 13
    I am having similar problems too, however my brakes arn't locked on. Under hard braking a little line of oil leaks out of the seal on each reservoir. The brakes still work but not sure how long they are going to continue working! I have ordered some new top seals and pistons (pistons needed replacing anyway)from a local shop but maybe i should be looking for some alloy top caps?

    How are you getting on crazycam?

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