Author Topic: leaking front caliper  (Read 955 times)

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Offline millerza

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leaking front caliper
« on: May 23, 2012, 06:42:41 pm »
78k 750 so after rebuild my front caliper started leaking, figured it was pitting on the piston. Ordered a SS piston and thought it was going to be good. So I put it on and rode a bit no leak. A day later I looked at it and the mother f'er was leaking again. What gives?

Offline TwoTired

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Re: leaking front caliper
« Reply #1 on: May 23, 2012, 06:57:41 pm »
New seal?

Read the Brake FAQ?

Cleaned the seal groove?
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Offline madmtnmotors

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Re: leaking front caliper
« Reply #2 on: May 23, 2012, 07:01:24 pm »
Make sure it's not wicking from the bleeder screw or the flare connection where the hard line connects to the caliper. The fluid can "wick" to a location other than where the actual leak is originating from and can be hard to detect without a very close inspection. Wipe everything off and check often for signs of fluid.
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Offline millerza

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Re: leaking front caliper
« Reply #3 on: May 23, 2012, 09:11:40 pm »
two new seals, no luck. Could probably have cleaned groove better.  I have thought of leak from another location but really appears from puck. I will try to clean groove though.

Offline MCRider

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Re: leaking front caliper
« Reply #4 on: May 23, 2012, 09:48:43 pm »
two new seals, no luck. Could probably have cleaned groove better.  I have thought of leak from another location but really appears from puck. I will try to clean groove though.
Its only a few places: Input line, bleeder valve or the piston seal.

I haven't finished mine yet and they weren't leaking. But they wouldn't retract. I disassembled them and the new seals (Square cross section O Rings) wern't the right size! See if your new ones fit snug to the piston first, then install.

I used the soft bristle brush with my Dremel to clean the grooves.
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