Does this look normal?

The pic below is of the piston and seal I just took out of one of my brand new calipers. Right after I did the front disc conversion I started having problems with the front brakes not releasing. Took this caliper off and compressed it with a C-clamp and the dust boot immediately popped right out on one side and fluid started pouring out.

My (possibly stupid) question is this: the piston seal in the pic has a twist in it about an inch long, with a notch in the middle about a quarter of an inch long. I suspect this is what was causing the problem with the brakes not releasing, but it appears to have been manufactured this way. Is this the way it was designed, or a manufacturer's defect?

 

Looks like you have found the problem to me.

 

I would suspect it got messed up on assembly. Just get a caliper rebuild kit and replace the seal with a new one. Or if it is under warranty get the caliper replaced.

 

Faulty caliper... get it replaced & your problems will be gone....

 

That confirms what I suspected. Thanks a lot guys! The caliper should still be under warranty so I'll get it replaced.

 

Put it back together and tell them it leaks fluid. I would not tell them you took it apart.

 

i agree with that statement...they dont need to know that you took it apart....if its under warranty get the whole thing replaced....if it isnt under warranty get a new seal and fix it


good luck!

 

Hey...I did that once when trying to rebuild a caliper!

 

Thanks, I may put it back together just for the heck of it, but I know the folks where I bought it and I don't think they're going to have a problem with it in either case.

 

Show them that square cut o-ring that is not square and they should replace it no problem.