John Deere H Hydraulic Pump

Hi all, thought I'd post some questions for those of you who have used the Hydraulic Pump on a John Deere H. I have one with the hydraulics and was wondering exactly how they worked when you lift up an implement. Do you raise the lever and leave it up, (and the oil ends up bypassing somehow when the implement is raised) or is there another method of operation for it. Also, would it in theory be possible to add a single hydraulic quick disconnect coupler? Grandpa has the shop manual for the tractor, I just don't have the ability to go out and look at it right now. Any responses are greatly appreciated.

The "H" Power Lift consists of the reservoir, a gear pump, the manual control valve, an unloading valve, a pressure relief valve, and a check valve. There is a special remote cylinder designed for the "H". When the handle is lifted fully up, the cylinder will extend. At full stroke, the hydraulic pressure will spike, flow through the relief valve momentarily, and that pressure spike will open the unloading valve which lets the pump move oil internally under no pressure. The cylinder will stay extended under load as the check valve prevents oil from returning to the reservoir. To lower the implement (retract the cylinder), push the lever completely down and it will overcenter and lock in place. The lowering speed is adjusted with a screw and jam nut next to the outlet. This action opens and holds the check valve which lets oil return to the reservoir. It also resets the unloading valve so that the next time you want to raise the implement, the system is ready for the control valve to send oil to the cylinder - if the handle is raised. The system was designed to raise fully up automatically (and then "shut itself off" with the opening of the unloading valve), and to drop the implement fully down when the handle is pushed down. It wasn't designed to stop raising in midstroke, although it is possible to do so.

Sent you an email message.
Richard in NW SC