> Hello all,
>
> I am having a bit of a problem installing a new set of pads on the 6. I
> got the rotors turned and attempted to install the new pads, no go, won't
> fit. Put the old ones back on and they just barely slide onto the disk.
> I tried the manual trick of opening the bleed valve whilst pressing in
> the cylinders. They moved a little but not nearly enough. Is there
> something I am missing here? How far should the cynlinders push back
> into the calipers? Any tricks here. It sure wasn't this tough when I
> did the Mustangs brakes!
>
Joe-
If a mondo pry bar won't push the pistons back into the caliper, you've
probably got a major case-o-rust on the pistons. Put one of your old pads
back in and a thin piece of something like a paint stirrer in the other
(you don't want the piston to come all the way out, and the wood will
provide a soft stop). Now step on the pedal til you feel resistance. The
piston should be out of the caliper almost all the way. Peel the rubber
boot around the piston back just far enough to see the surface of the
piston. Is it all rusty and scruffy looking. Yeah, I thought so...bummer,
you need new pistons. That's what happens livin at the seaside... If they
actually appear ok, use a little shot of silicone or brake grease inside
the boot to keep them from rusting. When the pads are new, the pistons are
pretty well enshrouded, but as they wear the piston extends from the safe
environs of the caliper into the ambient air mass. Humid air...well we know
what humid air does to unprotected metal, so you end up with bad pistons.
If the pistons are indeed rusty, you can still push them back into the
caliper, but the only place you should then drive that car, is to the parts
house to order new pistons and seals. When you push the rusty piston back
into the caliper, it usually tears the o-ring, and even if it doesn't, it
isn't gonna hold any pressure with its pitted surface.
Rust never sleeps...
Nick in Nor Cal
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