In a message dated 95-08-02 08:06:54 EDT, you write:
>I'm restoring my TR3B, currently a basket case. I unpacked the front disk
>brake calipers a couple of days ago. The PO apparently pulled them off the
>car ten + years ago without disassembling them. As time went by the pistons
>formed what appears to be a permanent relationship with the caliper
>cylinders.
>
>The calipers are cast iron and apparently of two piece construction. In
other
>words, the caliper halves can be separated, although research indicates it
is
>not a good idea to do so. My calipers do not have an end plug as shown in
>the Service Instruction Manual. I have successfully removed the bleed screw
>and flexible pipe. 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. Does anyone have and ideas about the
>best way to get the pistons free. All thoughts will be greatly appreciated.
>
>Jack Pepper
Your caliper cylinders are in the same condition as the ones on my
Spitfire...
Many are suggesting using pressure and/or disassembly of the caliper to free
up your stuck piston, but I plan to try to use heat to free mine.
I made the mistake of allowing one cylinder of each caliper to come all the
way free before unseating the second of each, so the pressure route isn't
quite so easy for me. Besides, I don't like the idea of my brake pistons
becoming "2 gauge" deer slugs. (They would be about two gauge, wouldn't
they?)
The plan is to fully clean one of them with alcohol, and put it in the oven
at 300 degrees Farenheit or so and see if that helps break loose the
piston.... Then, if they aren't free, I'll drop ice cubes into each of the
piston cups to maximize the temperature differential.
I don't expect to cause any damage by doing this, because my theory is that
I'm just doing a local simulation of some very spirited slushy winter
driving.
Any comments about my proposed plan and/or the likelihood of causing
damage???
I'd advise safety goggles, sturdy clothing (no shorts or short sleeves) and
some high temp gloves to boot, just to be on the safe side. Hot brake fluid
would probably be even more unpleasant than compressed brake fluid.
Michael Turley
Killjoy@aol.com
'67 Spitfire Mk2
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