Looks like I'm up for a bearing renewal in the top end of my drive. Its a 301 series bought in 2014 and then purchased by me second hand this year. I suspect that, before I purchased the kayak, the drive has had a dunking in the ocean and taken some water past the seals in the top drive unit.
The bottom end looked sweet as with no signs of water entry but I had probably a teaspoon of water in the top end of the drive and some rust on the bearings and main drive gear.
She had felt a bit "rough" the last trip and, being winter down under and the weather has been marginal for yakking I took the opportunity to do a tear down.
I think mutch longer and the bearings would have given me real grief if I had left it.
Luckily the bearings are cheap and an easy job to replace and while I'm at it I might try and fit an improved seal to the bearing. Will let you'all know how things go.