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Gregg, The thing floating in the oil is probably part of the return oil filter element. If the element gets plugged, the return oil pressure will rise and blow a hole in it. When you put the lever in the raise position, you are shutting off the control (by-pass) valve that normally will be circulating the pump output back to the reservoir. When the by-pass valve is shut the oil pressure goes to the piston via the lift check valve and raises the draft arms. When you put the lever back to neutral, the by-pass valve opens to recirculate the pump and the lift check valve closes, hydraulically locking the piston. If the return is restricted enough for the pump pressure to overcome the weight of the draft arms + load, the lift will continue to rise until the piston bottom out. When you stop the engine the pump pressure drops to zero but you still have a hyd lock on the piston. When you move the lever to lower position, the release valve opens dumping the oil on the piston into the return line. If the return is restricted you are using force other then gravity to drop the draft arms. Overgreasing the rock shaft bearings or an accumulation of grease over the years is generally the culprit. The grease accumulates under the piston and is pushed back to the torque tube through the leak-off/vent tube on the lower right side of the cylinder housing. If the hyd oil is not changed regularily, the grease in the torque tube is picked up with the oil and circulated blowing a hole in the filter. The filter element is under that 4 bolt flange located just under the fill plug. Element is cleanable, edgewound Case p/n VT3139 (A30411). After you get everything cleaned up, you may need to adjust the control(by-pass)valve and the release valve actuator clearances. Pull that leak-off/vent tube off there and blow it out also. Joe
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