After landing he will sometimes find the bendix drives on the
starters partially and occasionally

fully engaged. It does not happen every
flight but sometimes every other flight.

snip. Just yesterday we could see that on
one starter the bendix was retracted and could no be pulled forward with a
scribe. On the other starter the bendix gear was almost touching the ring
gear
and could be moved back and forth. There is a pin and spring arrangement
that

is supposed to keep the bendix gear retracted.

make sure the bendix drive shaft is absolutely clean. it is one
component which should not have any lubricant on it at all.

From: Stealth Pilot

I don't know about that. Lycoming recommends silicone spray lubricant. You do
not want too much lubricant or any type that will attract dirt that could turn
into gum or past that will bind the drive.

John Dupre'