I inherited a Kuhn GMD 600 disc mower from the 90's, it ran fine a couple of years ago and was parked in a field ever since. I went to hook up to it today and tried to lift the mower vertical for transport and the hydraulic cylinder just sprayed hydraulic fluid out of both ends of the cylinder and the mower did not move at all. I tried a different remote port on my tractor and tried moving the lever in both directions to no avail. I'm new to this mower and don't have a manual so I'm wondering if the cylinder is just bad or am I missing something like a lockout that is preventing the mower from raising?