With the help of this forum I narrowed down my hydraulic problem to the pump. Arms would not operate until engine ran at a fast idol for 15 to 20 minutes then would work intermittent and slow. Problem was air in the system. After bleeding the pump it would work just fine but if left overnight the problem would return. I ordered the kit and rebuilt the pump. The kit had an extra set of springs and also six new seats. I rebuilt the pump with out replacing the seats as my pumps seat didn't look like they were removable. Does anyone know if some pumps didn't have replaceable seats. My pump is working just great without the new seats but I would like to know if I am missing something. Were all the pumps made with replaceable seats and if yes how are they removed. thanks for any and all your help. This is a valuable forum. Terry