MF 178 Pump

[Tyler79]

Here's my situation- I bought a 178 a couple of years ago, and used it for most of the first season without needing the 3 point hitch. It would just go to the raised position when I started the tractor. When I eventually went to use it, I discovered that the arms would not go down with engine running. I took the lid off and discovered the control linkage (where one would remove the roller before lifting off the top) to be completely missing. Is there any reason one would remove this part? Besides needing to find another one, I'm wondering if there could be a problem in the pump/valve system that a previous owner decided not to fix, disabling the control side instead. Any thoughts/theories would be most welcome! Thank you.