Fortunately for me, I have never run across an air motor soaked in oil
or grease, and I have seen bad judgement calls on player pianos which
would make even the "biggest newbies (to the hobby) " cringe and blush!
Based on this, if I were to see an oil- or grease-soaked air motor,
I would _not_ be the least bit surprised.

I _do_ use Teflon spray on air motors on occasion.  Graphite is messy
and more time consuming and more difficult to apply.  Teflon spray
works great in the bushings and also with the slide valves.  Try not
to get any Teflon spray anywhere near the tuning pins.  Also, use it
in a well ventilated area.

If the air motor is _not_ running smoothly (I'll have already
adjusted the governor, etc.) and I see the body of the air motor where
the slide valves are is not all the same color, then I know the surface
the slide valves slide across and the valves themselves need to be
lapped with a glass block (220 and 320 sand paper, perhaps 400 as well)
and re-graphited.  I use the common method.  Mix the graphite with
alcohol to make a paste and spread it on all surfaces with a piece of
felt.

Some manufacturers of player mechanisms put a little sign the in the
piano, "Use only unsalted beef tallow."  Now, where the heck am I going
to find unsalted beef tallow?!

Bill Maguire