Remove the offending lifter and dismantle it. Mirror polish the plunger with a hard felt buffing wheel and jeweler's rouge or a similar grease-based polishing compound. I use the same type of polish to prepare firearm parts for bluing.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!