5 star hydraulic system

The small copper line coming from the top of the hydraulic resevior is just a breather vent. It is connected to the rearend housing to prevent dirt and moisture from being pulled into the system when the fluid level changes in the reservior. There is no pressure in the area of the copper line. I would look for any other cause for the cracks you mentioned to be certain there is not any mechanical issues that might have caused the damage or may have resulted from the damage. I have never heard of a system getting filled to that level with water and causing the type of damage you described. If you lift on the 3-pt arms, you should be able to lift them from the down position all the way to the raised stop without too much effort. The arms should move smoothly when they are lifted.

The pump is held on by two short bolts and one long bolt. I do not remember the postion of the long bolt but it is fairly apparent once you look at how the pump mates to the rearend housing.

Pushing the pto lever forward engages the pto. Pulling upward or aft disengages the pto. The pro will likely continue to rotate even when disengaged due to the friction in the clutch disc pack.

Hopefully this information helps. Please post back with any addition questions you have. There are alot of knowledgeable people that read this site that will be able to help you with you project.