Can you please provide some detailed images of said breather?
I have been somewhat into mine of late, I removed one of the annular pistons to check if I could remove clutches or not.
So far no luck I've got to split my case to get at the clutches
I've got a slightly different feel on one side compared to the other too, my LH side seems to drive forward more than the right or the right slips more when fully engaged in forward direction. My leavers do not LOCK they have to be pushed forward constantly.
Here are some pics of it disassembled as I've said.
First this decal was made up just for me and the machine! LOL
Now onto the clutches and transmission shots, here is the bearing cap, and lock nut holding shaft in place and annular piston in place
Once you remove the cap and big nut, and six retaining Allen head bolts, you remove the annular piston by pushing on the control leaver forcing it outward which then slides out as you can see here
The torrington bearing in that first pic actually rides against the piston on the dark ring
There is a gear as seen here inside the transmission, it's what the small swash plate rides against, and the bearing then the piston
Removed that gear and this is what it looks like
After that you can clearly see the clutch packs inside and NO I cannot access them at all sadly.
After all this a little cleaning and some reassembly and I was done with my investigation.
However I did do a small video of the function of the annular piston!
Here is the video or a link to it LOL
Hagen Transmission clutches and annular piston function - YouTube
That's what I've gotten so far, now I've gotta work on some clutches for the Kubota
Spoke to a fellow who says a Commet 780 Primary clutch and 860 Secondary clutch would work well the 780 with a green spring set for 1075 RPM egagement.
Nuff for now on this Hagen!