Just obtained a late 90s FX22D. Runs like a top, and backhoe and FEL work great, but the PTO seems to be constantly engaged even in the center position. Very sloppy play in lever, and no significant change in rpms when I put pto in different gears. Is this just a pto linkage issue?

Josh, 

The PTO system run on can be several things.  With your machine not being able to swap into another multi-speed PTO setting, this tells me you will need to open the PTO end of things to do a huge repair.  There are YouTube vids on this topic. 

The FX 2-digit machines have very limited information.  It would be best to contact Hoye, Fredricks Equipment, or Sheafer's T&C tractors for parts manual and possibly a service manual. 

See the Resource page here on our website under the WIKI on the bottom left side.  Carefully read and scroll that page.  It has nearly everything for Yanmar machines there all in one place.  

If you need parts, chances are you will, call EVERYONE on that list including the salvage ones listed.  

As you have more questions, our community is here to advise and bounce ideas to a solution. 

Steve