Hopefully the seal and gasket will fix the leaking problem. Be sure to check for loose bearing play where that seal backs up to.

 

Yanmar KNuckle Seal Replacement Instructions. (hoyetractor.com)

 

Looks to be an fairly easy fix.

 

The Hoyt instructions above don't match but are similar enough. While I'm awaiting the new knuckle seal, I've taking it apart. Here's the part's diagram of the right knuckle and what I did. Hopefully, this will help others in the future.

1) Remove tire.
2) Drained remaining fluid from knuckle by removing drain bolt - middle bolt from item 42.
3) Removed steering tie rod by unbolting item 52 (4 bolts). I didn't want to mess with a tie rod puller.
4) Removed bolt from top of knuckle - items 46-48.
5) Took a couple big flat screw drivers and pried the bottom part of knuckle - item 40 - off of assembly. It didn't take much effort.
6) The seal - item 26 - is in the upper assembly - item 35. Before I remove the seal, I want to see what the new one looks like.

I took come pics for good measure and they are in the next post.

 

Pictures of disassembled right knuckle....

 

Have you noticed any wobble or free play in that upper bearing? If so, replacing it now would be the best thing. If it’s tight and no wobble or pitting on inside of bearing surface it should be good to go. Wear pattern on pinion drive looks normal in the picture provide.