I have found that leaks with these ceramic disks is usually due to a particle of lime scale between the disks or a general build up of scale which can prevent close contact of the disks which require continual longitudinal freedom. A complete clean up of all components usually restores function, unless the disk surfaces have become abraded or scratched.
Remove cartridge (needs an allen key), take off retaining clip, oil shaft bearing and clean sufficiently to be able to push disk assembly out of housing. A gentle tap on the shaft end may help. Carefuly remove retaining rubber/ptfe washer and push out the ceramic disks. Thoroughly clean ceramic components - weak acid (ie dilute jenolite, phosphoric or weak hydrochloric) may help. Do not scratch surfaces. Clean scale from housing, especially close to the thin disk insert so it is not jammed on replacement. Clean up crud from shaft and o-rings but do not put o-rings into acid. Thoroughly rinse all parts before re-assembly in the correct order and orientation. Remember to replace the clip.
Martin Courtier
February 2010
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