With a radial we turn them over by hand to ensure that there is NO oil in the lower cylinders which could cause a hydraulic lock and do big $$$$$$ damage 😮 to the engine….most large eningines are turned by hand to ensure that all is clear and nothing is going to cause a hick-up when you engage the starter…the procedure of aligning blades is known as “dressing the props” for obvious reasons…blades up or blades down have many causes from that’s the way I want it to can I reach them and also on some fighters we put the blade up for towing etc….
I flew my Avenger together with a T-6, a Grumman Goose and a Beech 18 in the TV movie remake of “South Pacific” in 1999 starring Glenn Close/Harry Connick Jr [and me????]