rear brake caliper adjustment hex screw not working??

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Dweezle
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rear brake caliper adjustment hex screw not working??

Postby Dweezle » Sun May 31, 2009 12:06 am

Hi guys..
I have installed DBA Slotted rotors at front and new pads and lines.. all seemed fine..

Got to the rear.. passenger side all went fine, except where the hard line attachs to the braided line, threaded slightly so i have left the original line there for now.. will get a PRO to sort that out.

But the drivers side caliper adjustment screw turns .. very clunky like.. but the piston does not seem to move. i have removed the caliper and it wont budge.. no matter how many turns i do. :evil: :evil:

Would this mean i need a new caliper??
Do you need to do them in pairs??

Also there is NO fluid in the resevoir now from when the other brake line gave me a hard time it all leaked out after i undone it from the caliper. Would this at all contribute to the piston adjustment?? or is it mechanical like i suspect?
IS THIS GOING TO BE A PROBLEM?? a little worried that seals might dry out etc???

Thanks in advance for any help :D
ALL MUSCLE CARS ARE CRAP
Jeremy Clarkson

except of course, the Almighty VIPER!!!! 8)

Juffa
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rear brake caliper adjustment hex screw not working??

Postby Juffa » Sun May 31, 2009 1:16 am

Have you tried to remove the hex screw from the other wheel and use it on the dodgy one? I have one screw shared between both rear wheels.

It is very possible that you have the dreaded corroded slider pin issue. Have a read up on this issue on previous posts on this and the big forum.

No fluid will not be causing this issue, however as with any major work on the brakes, make sure you flush the brakes to remove any air from the system.

J
Former owner of Mailbu Stacey, Smurfette and Tweety.

wun911
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rear brake caliper adjustment hex screw not working??

Postby wun911 » Sun May 31, 2009 6:53 pm

Wait so you can remvoe the hex key thing from the caliper and drive around safely??? Then put it back in when you work on the breaks just to save some unsprung weight???
every ounce counts

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Dweezle
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rear brake caliper adjustment hex screw not working??

Postby Dweezle » Sun May 31, 2009 8:02 pm

hmmmmmm or you could shave your EYEBROWS :?
ALL MUSCLE CARS ARE CRAP
Jeremy Clarkson

except of course, the Almighty VIPER!!!! 8)

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Jimmy
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rear brake caliper adjustment hex screw not working??

Postby Jimmy » Sun May 31, 2009 8:46 pm

After spending all weekend essentially rebuilding my brakes I can say that the best method for removing the piston is compressed air. 3 out of 4 of my calipers were corroded and needed a rebuild. I took the rears to Carco and Russell stuck the nozzle to an air gun in and blew the piston straight out (sounded similar to a .22 going off). The problem with trying to force the hex bolt is that they strip easily and you are still left with a stuck piston. This may be your problem. See if you can get the hex bolt out and have a look. If it's turning and is "clunky" and the piston is not moving, then chances are you have stripped the bolt. But really that's not your problem; it's the stuck piston.

While you have the calipers off the car, it's a good idea to, once the piston has been removed, remove all the rubber seals and give the entire caliper a thorough cleaning, removing any rust and other crud (wire brush, sand paper and a polisher comes in handy). Clean and regrease all the rubbers and then reassemble. Don't skimp on the grease. While disassembled, it's also a good opportunity to see that the hand brake mechanism is working correctly (rears). My rear right was very dodge and was only working for the last 20% of rotation. With good clean and a regrease the mechanism was moving the piston pin as soon as the hand brake mechanism was turned.

Jimmy.
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Dweezle
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rear brake caliper adjustment hex screw not working??

Postby Dweezle » Sun May 31, 2009 9:33 pm

Thanks Jimmy... It was definetly a stuck piston.. the hex screws are threaded also.. so a bit of a lost cause

I have ordered 2 brand new rear calipers from the Uk.. 300 bucks delivered.. because i am looking at replacing the front also..
So my car will sit until they arrive, with the DBA SLOTTED ROTORS and New pads sitting also :frown:

.. 5 days i have been told. HOPEFULLY BY FRIDAY :roll: :roll:

now i just need to find out if they can replace rounded off flare nuts on the brake lines.. my rear ones on the hard lines are buggered... dont know what fool got to them before me.. GRRRRRRRRR prob didn't even use a flare wrench.. :evil:
ALL MUSCLE CARS ARE CRAP
Jeremy Clarkson

except of course, the Almighty VIPER!!!! 8)


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