f300 uhoh

[tungularafishcamp]

Something started happening with my f300 this am. Idles smooth but as soon as I put it in gear rattles and vibrates and acts as if it is missing on a couple of cylanders.(both forward and reverse are rough) As soon as I speed up it goes away. Prop is fine and I drained out a bit of lower unit oil and it was the normal yamaha hd gear oil too damn dark and just the normal little bit of metal fuzz on the magnet.
Any ideas out there, I am in bush Alaska with the nearest yamaha mechanic and shop only 500 miles away(by boat)
Thanks,
Rick

[rodbolt17]

is this the V6 or V8 f300.
made two versions. there was also a Z300 two stroke.