New to the forum and was hoping someone could help me out. My 4100s Hydraulics keep getting stuck in the up position. First time I took it to the dealer and ended up costing me $800.00. Mowed a couple more times with it that fall and used to blade during the winter, everything worked fine. Went to put the mower deck on in the spring and hydraulics wouldn't go down. Took out the part JD had put in and blew it out with air compressor, things worked fine again. I do most of my mowing with a scag turf tiger so the Deere doesn't get used a whole lot but I wanted to mow with it the other day and the Hydraulics are locked up again. My manual doesn't have a part breakdown and the blowing air into it didn't work. Can anybody help me out with this problem. Thanks in advance for the help.