Soaking them in CLR will do a good job at removing any calcium or lime, then you might rinse them in some vinegar water mix to dislodge any elements of sand out of the bearings and traces.
While these elements will not affect the stainless steel bearings, the sand will erode the nylon track and eventual replacement becomes inevitable.
more bearings are now "shrouded" to reduce cinders of sand getting into them. This is the reason some have developed jet actions that do not include "moving parts".