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I am having trouble with my front Hayes brake. I am leaking fluid like crazy, and I believe that the fluid is coming from inside the piston. Is this possible? I have tightened the bleed screw, the coupler, and have bled the brakes 3 times in the past week. I know that something is going on with the brakes but I am having a hell of a time finding it. Does anyone have any suggestions? I got the brakes from this website's classified section, and they were supposedly new. I do believe that they were new when I got them, or at least in excellent condition. Can the calipers be rebuilt? What is required for a rebuild? I am sure that there are seals in the caliper, and my hope is that one of them is bad and needs changed. Thanks for any advice anyone has.
 

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uofabill
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Don't know for sure...

about caliper problems, but I just got thru dealing with a problem with the same brakes that turned out to be a hose problem.
What I have learned is that those brakes are pretty simple. If you haven't done it, go to the Hayes web site and download the manuals and there are exploded diagrams of the different components.
The calipers look really simple internally.
From what you are describing and from what I have read, one possibility is that you might have a "post" (that the pads attach to) that may have gotten pushed back thru the piston.
If that isn't it, it may be the "square seal." This is a "square O-ring," that seems to be the "heart" of the caliper and what makes it retract and also seals the mechanism from leaking fluid.
I would detach the caliper from your shock or frame and wash it thoroughly with alcohol. Then either squeeze the lever carefully or have someone else do it. Either get in good sunlight or use some kind of bright artificial light look closely for leaks.
Part of the caliper housing may be cracked, a piston could be cracked or the post may be pushed through the piston or broken.
If can't locate the source that way you'll have to disassemble the caliper and see if the the square seals are damaged or worn.
If you do those things you should be able to locate the problem.
Looking at those exploded diagrams should give you a good idea of what the insides look like.
Good luck!
 

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Sounds like it is either a hose problem (compression olive is crushed too much where connects to caliper) or one of the piston seals is torn.

You can get replacement seals from LBS, they are dirt cheap. Pistons can be popped out with compressed air (after fluid is removed from system). The seals come with instructions for re-build.

TJ
 

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It could be a cracked caliper piston

aspang said:
I am having trouble with my front Hayes brake. I am leaking fluid like crazy, and I believe that the fluid is coming from inside the piston. Is this possible? I have tightened the bleed screw, the coupler, and have bled the brakes 3 times in the past week. I know that something is going on with the brakes but I am having a hell of a time finding it. Does anyone have any suggestions? I got the brakes from this website's classified section, and they were supposedly new. I do believe that they were new when I got them, or at least in excellent condition. Can the calipers be rebuilt? What is required for a rebuild? I am sure that there are seals in the caliper, and my hope is that one of them is bad and needs changed. Thanks for any advice anyone has.
It could be a cracked caliper piston or a bad seal. Also there is a O-ring between the caliper halfs, if it is bad or missing it will leak. Here is the caliper piston kit http://www.balleracing.com/Hayes_Caliper_Piston.htm
Erik,
Balle Racing
www.balleracing.com
 
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