I have a JD 425 and a 60" mower deck. I also have a 48" front blade with an angle kit attachment. I had the blade hooked up and it was operating fine - up/down and side to side. I took the blade off after the snow melted and turned the toggle switch off to the blade hydraulics. I then tried to hook the mower deck up. The arms to the deck would not come down. I managed to raise the mower deck up high enough to lock the arms in. The top lever arm which operates the up/down for the mower deck would not raise or lower it. It was high so I mowed my horse pasture with it that way. Now, 2 months later, I was going to mow the pasture again but by sitting for this amount of time, the mower deck has lowered itself down to a very low height. The top lever which should raise the deck is not working. I have checked all the oils, transmission is high and engine oil is good. What am I doing or not doing? in order to get this mower deck to raise up and lower down? Thanks!