In article ,
"O. Sami Saydjari" wrote:

In reading a booked called "Design for Safety", by David Thurston, he
advises owners to "turn the propeller over by hand three or four times
during preflight if the airplane has been standing for half a day or
longer." [p169]

How old is the book? This sounds like something that would be advised
for radial engines, where such issues (called hydraulic lock) were
indeed a problem.

Unless your aircraft manual specifically advises you to do this, I
wouldn't.