Thanks Elizabeth. Washing - yes. Not sure about lotion. Don't know what chemical interaction might be involved.

Yes, Giovanni, I have a service manual. They appear to be fabricated such that it is easier to change complete octaves than it is to change a single key. Since my problem is in the area where chords are often played, I plan to shift a complete octave from an area that is not used so much to where the bad keys are and put the bad keys in an area where I seldom use them. But that will only be done after I try a simpler method, if there is one.