Someone told me about this assertion he heard somewhere.
It doesn’t make any sense to me. Can anyone explain it?
The crankshaft bearings are axially symmetrical and don’t know anything about the propeller position.
Propeller stopping location is the compression stroke in every cylinder, all other factors are negligible. On the other hand, speaking of axial symmetry, I have measured dozens of crankshafts and bearing inserts, and the old ones are, well, potato-shaped and potentially eccentric, especially the inserts. Nevertheless, for an engine in operation it makes hardly any difference. Things may happen after an overhaul if new inserts are paired with an old crankshaft. On a couple of occasions, we heard strange noises on the ground test bench, but only with bronze inserts, never with Babbitt-coated ones.
Peter wrote:
Someone told me about this assertion he heard somewhere.
In which I would ask the person as to the reason why and how…
Crankcase fretting mostly happens when the case halves are not properly torqued, or sometimes mated. People sometimes pull and reinstall cylinders without knowing about the thru bolts and their specific requirements.
I thought it was BS but asked anyway 
