compare '87 and '90 rear caliper

[Kneale Brownson]

>From my disassembly of '86 and '91 rear calipers, I presumed the spring in
the piston served the purpose (probably less effectively) of the spring
between the snapring and the base of the threaded rod.

At 04:55 PM 1/12/2004 -0500, Nick Lawrence wrote:
>I have taken apart several rear brake calipers from '90 and '91 type 44 cars 
>and I think I have a good idea how they work.
>I took apart a rear caliper from an '87 type 44 and it was different,  don't 
>know if was assembled wrong before.
>On the later caliper: 
>    -remove piston by unscrewing
>    -reach into cylinder and undo the snap ring and out             comes 
>the spring and smeet metal retaining device
>    -wiggle the course thread rod and out it comes with a         plate
>
>On the earlier caliper:
>    -remove the piston
>    -reach into cylinder and undo snap ring
>    -nothing spring loaded in here at all!
>    -course threaded rod is held in very snug fitting stamped
>    metal plate that has tabs to prevent the rod from turning
>There appears to be a spring inside the piston on the earlier caliper.
>   
>The later caliper uses the internal spring under the snap ring and cover to 
>push the threaded rod back when the park brake is released.
>
>What causes the threaded rod to retract on the earlier calipers?
>Any insight on this will be appreciated.
>Nick
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