Jack Pepper wrote:>The pistons are protruding out of the cylinders
>approximately 1/8 inch. The calipers are currently soaking in a brake fluid
>bath and have been for several days.
Hope there was still a bit of fluid coating the inside of the calipers so
the inner bore isn't rusted. A penetrant around the pistons left for a few
days will help to loosen some of the external rust. Scratch away as much
visible rust as you can with an X-acto knife.
I've had good luck in a few cases by just applying brake pressure to push
the pistons out. If the master cylinder is functional or repaired,
temporarily hook up the caliper with old pads in place, bleed it and apply
pedal pressure. The pads keep the pistons from popping out if they free up,
you want just a little freedom not total liberation. :-)
If it works, one piston will no doubt break loose before the other. Put a
stout metal strap or angle iron across the one that moves and use sturdy
C-clamps or bolts to restrain it in the caliper body. Then you can continue
to apply brake pressure hoping to loosen the other one. Keep a brake pad or
two in the gap to restrain the second piston if it suddenly breaks free.
As a last resort (it places your bore at some risk from the rust), try
pushing and pounding _in_ on the pistons with the maximum brute force you
can muster. The smallest motion will break the rust and allow you to use
brake pressure or shop air pressure to remove the pistons.
Good luck!
--
Gary Schneider, Nicolet Instrument Technologies
phone: 608-276-6172, Fax: 608-273-5061, Internet: gschneid@nicmad.nicolet.com
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