I cant figure it out. I was using brush hog with my 1955 Ferguson T. O. 35 and all went well. When I turned the PTO off and hooked up a blade the 3 Pt. hitch will only go up, what have I done? If I turn the tractor off and let the load fall on its own(which is normal) when I start the tractor and let out the clutch no matter where the up and down control is the blade raises to the maximum height. Thanks in advance for any advice.