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Discussion Starter · #1 ·
Hi,

I've bought new Shimano XT m785 brakes.
After first real ride I've noticed a little of oil on caliper around bleeding nipple. I thought that maybe it wasn't tightened all the way, so I tightened it a little bit more.
After another ride there was again a little of oil.

Rear one looked ok after first two rides, but today I've noticed a little bit of oil also on the rear caliper. What is interesting to me is, that previous two rides were steeper with more braking but there was no oil on rear caliper.

What do you think, is this normal, is this happening because brakes are new? Did anyone experience anything similar?

I've already owned a pair of m785 brakes for about two years, but didn't notice anything like that.
 

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I'm having the same issue, but the fluid is clearly coming out of the bleed vavle/fitting on the caliper. Is it possible that the brake is over filled/too much fluid?
 

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Get it into some good light and closely study the swaged brake fitting where the plastic hose goes into the aluminum swage. You "may" see a very slight gleam or glistening of fluid at that interface. If so, you could have the end result of a bad batch of hoses that came through at one time. I experienced the same myself. The mineral oil can and will wick all over the caliper and contaminate the pads and appear to be coming from a source that it really isn't or it will be nearly impossible to tell it's source. It's certainly possible it could be leaking from the bleed nipple but that would be unusual and the hose issue is/was a known problem.

I directly contacted a Shimano Tech Rep by phone and without question, he offered me immediate replacement of hoses and also new F03C pads. We did the exchange through Art's since I live within minutes. They called and credited Art's and I grabbed the parts I needed and was made whole in just an hour or so. Check it out!
 

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Yeah...I no about it leaking around the hose fitting but it is clearly coming out of the bleed fitting /valve as I have wiped it of before riding and then checked it after a half an hour of riding and there is oil coming out of the nipple
 

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Occasionally Cranky
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I don't have these particular brakes, but a couple ideas for fixes if it's leaking from the bleed nipple:
1) If there's an O-ring at the nipple/caliper interface, check and make sure it's still good and not pinched/torn/etc.
2) If there's no O-ring, you could apply a small amount of teflon tape to the threads where the nipple is inserted into the caliper.

Hope it works! :)
 

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Magically Delicious
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Leakage is not normal and any leakage is unacceptable.

Assuming that you've isolated the leakage to the bleed nipple, I suspect that it has a seating issue or an 'O' ring problem. Prolly not too difficult to troubleshoot.
 

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The nice thing about Shimano is that they are really good at sorting these things out. I had brakes with weeping callipers years ago and they swapped them for a whole new set of brakes. You shouldn't get faulty kit in the first place but it helps when you are confident they will sort out any issues you do have.
 
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