starter solenoid click

["Dave Stoll" <dgstoll@mint.net>]

The starter solenoid has started to click but after several tries the
starter kicks in and does it't thing.  I notice that the ammeter does
not go negative when the solenoid clicks.  Would this indicate  the
solenoid is acting up or will a worn bushings in the starter do the
same thing?  Is there any maintence that can be done to the solenoid?
(I do have a spare starter in the trunk for the eventual emergency)
daveS