I am a proud new owner of an old Kubota B20. I removed the backhoe, and am trying to connect a brush hog. The PTO turns nicely. However, the arms do not go up or down. Where do I begin? I checked the hydraulic quick disconnects, and they appear to be connected correctly. I did adjust the arm lowering speed control knob under the seat to make sure it was in an "open" position. I also tried to tighten the bolt on the lever controller. No luck. This is my first time at this, so any help would be appreciated. Under the gun as Fire Brush Control clearance is upon me.