rear brake caliper

[Michael and Stacey Rollins]

I just finished installing pads front and rear and front rotors on my '99
A4.  The rear calipers definitely needed to be rotated in a clockwise
direction when compressing the pistons.  As Tom noted, make sure you vent
the resivoir before compressing the pistons.

I honestly don't know if the rear calipers need to be rotated on your 4K,
though I'd like to know for future reference.

I compressed the front pistons with my hands with constant pressure.  I
didn't have a C Clamp large enough to fit over the caliper... ;)

Mike
----- Original Message -----
From: "Tom Christiansen" <tomchr at ee.washington.edu>
To: "George Nimmer" <george164 at earthlink.net>; <quattro at audifans.com>
Sent: Monday, March 31, 2003 7:58 PM
Subject: Re: rear brake caliper


> George,
>
> >I have the lisle brake piston tool that "screws" the piston back into
> >the caliper.  There are different "bits" included that fit different
> >pistons.  The pistons on my car are perfectly flat and have no dimples
> >that these keyed "bits" will fit.  The pistons only have a six-sided
> >hole in the center.  How do I push these pistons back into the
> >calipers?  Which direction (clockwise or counterclockwise) do they turn
> >while being "screwed" back in?
>
> I'm not 200% sure, but I don't recall hearing about caliper pistons that
> required to be rotated while pushed in. I've normally just pushed the
> piston in. Remember to take the cap off the brake fluid reservoir while
> pushing the piston back. Collect overflow fluid and discard at your local
> recycling place. Do not re-use brake fluid.
>
> >The Left Rear caliper doesn't seem to be working.  The disc is all
> >rusty.  When the car is off the ground on four jackstands, and someone
> >pushes the brake pedal, the Left Rear wheel can be turned easily by
> >hand.  Do I have a bad caliper?
>
> Sounds like either the caliper doesn't get any hydraulic pressure through
> the brake line or the piston is stuck. I bet there's air in the brake
line.
>
> As someone else said, when working on brakes you're taking your life and
> the life of others into your own hands. Make sure you know what you are
> doing. Common sense applies.
>
> My $0.02 worth.
>
> Tom
>