175 Diesel Hydraulic valves

You might be pleasantly surprised !!  If the rubber dust plugs were still installed at the rear of each spool, that should have kept rainwater out. If not, I'd stand the valves on end and fill each rear spool cavity with penetrating oil and let it soak for a few days. Polish the exposed front of the spools to get rid of any rust. Try them and see if they will move and detent.

Well, you need to sit in the seat of any D17 IV, 170-175-180-185-190-200-210-220 or 7000. They are the nicest operating levers ever made.

4-positions on the remotes....raise-hold-lower-float.

While off, check all the linkage to make sure the levers move freely on their shafts. Especially the one the pushes in the position spool which relies on the spring to return.

Three detents....four positions. Sounds right to me.  Raise is the full in position and it isn't 100% in.

DSeries4 wrote: Make sure EVERY pivot point in the linkage is well lubricated and moves freely by hand - not by moving the levers!  If the valve body leaks a lot AGCO sells a kit to replace every O ring and seal.  I did it on mine and it made a world of difference. However, I did have one hydraulic section I had to replace.  It's hard to describe, but it was very hard to move and would kind of only work one way.  Used it on the loader for several years that way.  We had to switch the hoses around to get it to lift and used the float position for it to lower.  Our hydraulic shop couldn't repair it, but they got us a new section for around $100.