Bleeding shimanos with the wrong brake fluid

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Bleeding shimanos with the wrong brake fluid
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Posted: Jul 25, 2014 at 17:18 Quote
So bleeding brakes is next to brainless...or so I surmised..then I bled my saints with Dot5 fluid because that's what I used on the avids I used to own no matter that it clearly says "mineral oil" right on the cylinder head of the shimanos. Anyway this starts my story. Approximately three weeks after bleeding with the Dot5 I notice Dot5 leaking from my cylinder head and my brakes getting less effective. I thought to myself "crap I used the wrong fluid" immediately. So I called the shop who quickly suggested a new brake. I looked on forums for a fix to no avail. I then took out the Dot5. Flushed the system with alcohol (not the Glen Levit type) and let it air dry with both ends open over night. The next morning I blew it out with compressed from the caliper to the top and refilled with the proper shimano mineral oil (I tried to get away with OTC mineral oil but decided to use that for a nice dump and buy the rediculously overpriced "specially formulated" shimano type cause I like that it's pink and I already screwed the pooch on this project once). Breaks were about 30% after this bleed but they eventually failed a day or two later. I bleed again and again. Tried to find replacement gaskets without success ( I mean why should shimano make replacement parts for stupid people?). After a solid week of problem solving I ran into a guy completely unrelated to biking who said he makes his own gaskets with liquid gaskets for everything. So at my wits end in a last ditch effort to save a $250 pair of brakes I tried it. HOLY ***T! It worked. My brakes are restored! I'm a fricken genius in a dumbass sorta way! I wanted to share it here if there is by chance anyone else out there who is trying to avoid breaking the bank due to similar circumstance. Don't believe your friendly local bike mechanic who is well intentioned but possesses an inherent conflict of interest. The stuff I used is AVR silicone gasket maker. Sorry for the saga but that's what it's been!Smile good luck!

Posted: Jul 25, 2014 at 21:18 Quote
I know of someone that got some seals made so he could use mineral oil in some Avid brakes.

He had a mineral oil TRP Parabox on a road bike and wanted to put 4 piston brakes on it, the pistons of the Shimano Saint/Zee brakes didn't match up with the TRP master cylinder but the pistons of the Avid XO Trail did.

The problem was getting mineral oil compatible seals for the Avid brake, I gave him a link to company that makes hydraulic seals, he contacted them and they said they could make what he needed.

He got the seals made for $3 a piece, he also had to get mineral oil compatible o-rings and new hose connections, the mineral oil conversion worked and he was happy with the performance of the new setup.

Posted: Jul 27, 2014 at 7:16 Quote
RediciouslY overpriced? ?????
It's $25/L you keep your warranty and Will get 60 brake bleeds out of that don't be cheep. Your running high end brakes and gonna bitch about ballpark 50 cents a bleed in fluid? ???
Lesson learned glad it worked out for you.

Posted: Aug 8, 2014 at 20:55 Quote
"Don't believe your friendly local bicycle mechanic" Ha ha, interesting advice from Dirty the Sanchez.
I've been a mechanic at shops now for over 15 years and i feel like such a fool for telling my clients who used the wrong fluid in their disc brakes that they'll need new brakes because the seals have been compromised. Can you post your address so we can send all the brakes to you to fix?
I mean its not like the brakes are very important and silicone gasket maker is sure to be a long term fix in any high pressure brake seal that is contaminated.
How many rides has your silicone fix lasted? Shimano, Avid and others test their brakes for hundreds if not thousands of hours by professional riders before releasing them onto market. Please keep us updated as your post is only 10 days old.
Whats next in the Sanchez mechanics tool box? 2 part epoxy to fix worn drivetrains?
Folks please refer to your brakes proper fluid and maintenance guidelines for your exact brake model and stay away from back yard fixes, especially when it involves your brakes.

Posted: Aug 8, 2014 at 21:33 Quote
DirtyTheSanchez wrote:
I wanted to share it here if there is by chance anyone else out there who is trying to avoid breaking the bank due to similar circumstance. Don't believe your friendly local bike mechanic who is well intentioned but possesses an inherent conflict of interest. The stuff I used is AVR silicone gasket maker.

I needed a hearty laugh tonight and this post delivered.

I would suggest posting this mechanic "tip" on http://failblog.cheezburger.com/thereifixedit because that is where it belongs. Though, seals are hard to see so it may not have the visual impact needed for this site. Maybe the original poster could send some pictures from the hospital bed after his brakes fail at speed?

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