I've searched the archives regarding replacing cutlass bearings, and it appears to be very easy to tell if one is gone if the boat is out of the water. But what do they sound like when they are going bad? Grinding, rattling, banging???? Howling, like a car wheel bearing? Audible at all rpms, or just low rpms? Does it come and go, or will it be constant? Any way to tell a worn cutlass bearing from a poorly centered shaft that may be hitting the shaft tube, or misaligned shaft? I'm trying to identify some strange drivetrain sounds---a grinding and an ocassional rattle/banging, loud enough to be heard resonating through the hull. It has always made this sound at idle speed, but lately can be heard at higher rpms, and now is much louder. Yesterday I did some experimenting at the dock. Standing on the dock at the stern, the sound is clearly audible. Working through foward, neutral and reverse at different rpms... ... it never occurs in neutral ... it may occur at low rpm and vanish when taken slowly to a higher rpm, or it may continue at a higher rpm and get a little louder. ... moving from one gear, idled down, and shifted to the other may make it vanish, though once it starts, if it doesn't vanish at a higher rpm, it seems to remain regardly of rpm until taken out of gear and shifted to the opposite gear When the sound was audible, I went below with a mechanic's stethescope, and could hear it best when touching the skeg bolts---a grind with an occassional hard thump (in the earpieces, which magnify things considerably). One person thought it might be the transmission damper plate, but with the stethescope, I could clearly eliminate this possibility, even over the engine noise. One mechanic suggested grabbing the transmission and pushing it back and forth to see if I could eliminate the sound...I tried this, and the volume diminished, but the sound was never eliminated entirely...when it was occuring. By the time I finished with all this fooling around, it wasn't making any noise at all!!! I know, it will wait until I really need to motor.... Any thoughts????