Hi Mitch, The coupling hoses are a done deal, already made and much too expensive.
As for what I mentioned in my post; those are just the possibilities the service manual gave me. I know that most won't apply here.
I took one of the valves I replaced apart to see what was inside and what I was dealing with. I wasn't able to take the spool apart because I could come up with a combination of punches that would break the retainer free. I'll have to either by the spanner of keep pondering on that. Or I just might take it to the agco dealer and let them take it apart and put new o-rings in it...then just swap it back onto the tractor.
This entire project is me throwing money at something I didn't understand. But I'm working on that part. I got the two replacement valves for less than half of what the local salvage yards wanted so I'm good with that part too.
The original ones I took off are likely just needing a rebuild, after taking the one apart I saw what I supposed was good parts; not a lot of metal to metal wear (just some normal brightening where they contact), no scoring that I could see inside the bores, the poppets still had little sealing ridges around the cone face, the springs looked good and felt good (not a great indicator since they are seriously strong springs), the metal balls all looked ok, just the o-rings seemed to be needing replacing, they had taken a set with a flat face. Overall, I would call the one I took apart good as soon as I replace the 0-rings. At least nothing abnormal jumped out at me. Normal is relative since I don't know what new looks like.
The used one I put on the tractor that is being a problem I haven't had apart yet. I doubt the plunger is bad, but there is a the likelihood that the poppet in the spool is bad. That would leak oil past the poppet when it's closed pushing the cylinder out (I think from reading the manual) The plunger below the spool is only to allow oil to return as the cylinder moves in and out. It's doing that (at least in one direction) so it's doubtful that's the problem.
I was hoping to fix it while it was still on the tractor. But the solutions in the service manual are all over the place. I don't have the resources to check all those suggestions. But if you think I can remove the bottom plunger without losing massive amounts of oil onto the ground I think I'll try that first just eliminate that possibility before I drain the system and take the valve all the way off. I can just strain the oil before I put it back in. But this won't happen today, I'll need to wait til Monday to get all the new o-rings I'll need to use since I'll have it apart.
Thanks for the info. Sorry I write so much but I believe in being thorough with my descriptions and being succinct isn't in my blood.