> I was beginning to rebuild my '71 TR6's brake calipers and have
> taken the
> snap ring and rubber boot off. The pistons seam frozen and I
> can't remove them.
> I tried compressed air as suggested in the manual but with no
> success. Will I
> need new calipers or is there another way to remove the pistons?
There are several ways to remove them, unfortunately most of them involve
separating the caliper halves (which the book says not to do) so you can
replace the O-ring between the halves.
Probably the safest method is to make up an adapter so you can pressurize
the caliper with a grease gun (which will develop far more pressure than
your air compressor). You can drill and tap an ordinary bolt to take a
grease zerk. Bit of a mess to clean up afterwards (be very certain you've
got absolutely all traces of the grease cleaned up, and replace any rubber
it comes in contact with), but the good news is that grease doesn't explode.
I usually take a slightly more exciting approach, and partially fill the
inside of the caliper with brake cleaner. Then stop up both outlets (with a
bleed screw or bolt) and start heating the caliper with a propane torch.
Once the brake cleaner boils, it will eject the first piston. Keep your
face away and wear eye protection, you don't want a faceful of brake cleaner
! Also stick a piece of wood or something between the pistons, so the
flying piston can't damage anything.
Generally with any method, once the first piston comes loose, you'll be left
with the other piston refusing to move. Clean up and lube the first piston
(so it will come out easily next time), put it back in the bore, and clamp
it in place. You might have room to get a big C-clamp in there, but I
usually use two bars of steel with C-clamps to hold them together. Then
extract the other piston.
Most likely, if they're that frozen, you'll have to replace the pistons.
But they're a lot cheaper than complete calipers.
HTH
Randall
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