Author Topic: Ok what's I do? Brake caliper/piston problem  (Read 1783 times)

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Offline ncstatecamp

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Ok what's I do? Brake caliper/piston problem
« on: November 20, 2012, 11:49:00 AM »
Reassembling my brake caliper, new seal, piston is clean, caliper polished and the piston is stuck.

I cant push it in or pull it out (havent tried to pull that hard). What's goin on here?

Offline goldarrow

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Re: Ok what's I do? Brake caliper/piston problem
« Reply #1 on: November 20, 2012, 11:53:57 AM »
Use grease gun to push it out, or put back on the brake line and squeeze out
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Offline 70CB750

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Re: Ok what's I do? Brake caliper/piston problem
« Reply #2 on: November 20, 2012, 11:55:02 AM »
What he says:)

Did you lube the piston?
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Offline dave500

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Re: Ok what's I do? Brake caliper/piston problem
« Reply #3 on: November 20, 2012, 11:58:28 AM »
it hasnt gone in squarely,see what side is out of square and tap it gently itll go in.

Offline ncstatecamp

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Ok what's I do? Brake caliper/piston problem
« Reply #4 on: November 20, 2012, 12:00:13 PM »
No brake lines yet, so that's on option out. It's not that deep I should be able to grab it out.

What should I use to lube? Brake fluid?

Offline ncstatecamp

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Ok what's I do? Brake caliper/piston problem
« Reply #5 on: November 20, 2012, 12:02:49 PM »
it hasnt gone in squarely,see what side is out of square and tap it gently itll go in.

It be square just not moving....

Offline Toxic

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Re: Ok what's I do? Brake caliper/piston problem
« Reply #6 on: November 20, 2012, 12:03:59 PM »
Before you pump it full of grease, try compressed air.
Cover the piston with a rag and use your air compressor to blow it out.  If you don't have an air compressor either find a buddy with one or take it to a local garage. They shouldn't charge you more than a couple of bucks.

As a last resort use the grease gun method, it works .... just messy

Offline ncstatecamp

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Ok what's I do? Brake caliper/piston problem
« Reply #7 on: November 20, 2012, 12:06:33 PM »
Nvm airgun ftw!

But back to lubing....

And I feel like an idiot for having to ask but there's not a direction that the seal goes in is there? (it's square right?)

Offline TwoTired

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Re: Ok what's I do? Brake caliper/piston problem
« Reply #8 on: November 20, 2012, 12:44:17 PM »
The seal is square section.  It's the caliper groove bottom that is machined at an angle.  And, all the groove faces should be thoroughly cleaned before reassembly.  Use compressed air to remove the piston if you assembled it dry.  BTW, you should dry assemble without the seal to verify all the parts slide properly in the bores.  New pads often need filing for proper fit.
Brake parts assembly lube for the seal is best.  Not many parts stores still carry it in stock, though.

You *CAN* use brake fluid.  But, this will lead to corrosion and crystalization issues later in time.

Have you checked the brake FAQ, yet?
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Offline Harsh

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Re: Ok what's I do? Brake caliper/piston problem
« Reply #9 on: November 20, 2012, 02:20:42 PM »
TT...I am in contact with the OP and heading in his direction for Thanksgiving so we are going to try and meet up so he can use some of my Dow HVG and Willwood brake assembly lube.

Offline ncstatecamp

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Ok what's I do? Brake caliper/piston problem
« Reply #10 on: November 20, 2012, 02:42:20 PM »
The seal is square section.  It's the caliper groove bottom that is machined at an angle.  And, all the groove faces should be thoroughly cleaned before reassembly.  Use compressed air to remove the piston if you assembled it dry.  BTW, you should dry assemble without the seal to verify all the parts slide properly in the bores.  New pads often need filing for proper fit.
Brake parts assembly lube for the seal is best.  Not many parts stores still carry it in stock, though.

You *CAN* use brake fluid.  But, this will lead to corrosion and crystalization issues later in time.

Have you checked the brake FAQ, yet?

Yep just read up on it. I got it apart with some compressed air, popped right out. As for test fitting I've done that, everything fits beautifully. The piston almost vacuum fits without the seal.

Offline ekpent

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Re: Ok what's I do? Brake caliper/piston problem
« Reply #11 on: November 20, 2012, 05:03:57 PM »
Did you clean all of the white built up crud out of the groove well that the new seal goes in on the caliper ?

Offline ncstatecamp

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Ok what's I do? Brake caliper/piston problem
« Reply #12 on: November 20, 2012, 06:25:11 PM »
Did you clean all of the white built up crud out of the groove well that the new seal goes in on the caliper ?

Yep spotless, dremeled it all out. And noticed the slight lip/indentation