MF 1150 Hydraulics

[Somuchjunk]

I recently acquired an 1150. Works great except the hydraulics. When you raise an implement it works fine but when you put valve lever back in middle the implement drops. Its like its on float. Happens on both remotes. I changed hydraulic oil, filter and intake screen in trans. Any ideas what could be causing this? Im used to IH tractors and Masseys are new to me. Thanks