Originally Posted by
Jhieminga
The current suspect is the accessory drive shaft. I don't know enough about R-1830s to know whether that's a big or a small job. I suspect it's a big one though.
I don't know enough either, but this, courtesy of the US Navy, makes it sound like there's not a huge amount of disassembly involved in replacing the accessory drive:
I hope I'm right.