I’ve been busy with other projects for the past two years and thus have been
off the list for some time. Of course the way these things turn over,
probably no one here was here when I used to be …
Anyway, my current workshop project is the complete rebuild of the rear end
prior to being able to use the car any time we like.
The brake calipers were frozen up badly. After much effort I managed to
get the old pistons out using a combination of air pressure, long soaks in
WD-40 and a bit of heat. I purchased replacement pistons from XKs
Unlimited. The replacement pistons do not have the little circular spring
arrangement in the center of the piston. They do have a recess machined for
this feature, but the mechanism itself is not there.
My Jaguar shop manual says these pistons are non-serviceable, and the little
spring mechanism in the old pistons is staked in by dimples in the piston
As far as I can figure, these contraption is a sort of self-adjuster which
serves to keep the brake pad always in contact with the disc. I’ve never
seen this on any other disc brake system, and perhaps it is something which
was later deemed unnecessary.
Did CSK’s ship me bad/incomplete parts? Is standard practice now to do
without the self-adjust feature? If so, should I remove the pin from inside
the cylinder bores?
TIA for any advice!
[Commercial use of subscribers e-mail addresses prohibited.]from my '67 420G. Hopefully this is the last major system needing attention
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