Eagle hitch and loader valves on same hydraulics?

Hi,

What is the correct way to hook up both the Eagle hitch and a additional 2 spool valve for a loader on a VAC?

My project tractor essentially has the output from the pump wye'd to both the loader valve and eagle hitch valve. The output from both are also wye'd to the return line. At the Eagle hitch there are shut off's at both the input and output.

The loader works fine when the Eagle hitch shut offs are closed, however when I open the Eagle hitch shut offs the hydraulics are very sluggish. Engaging the loader valves will affect the Eagle hitch and vise versa.

Is there simply not enough pressure to opperate both systems? Or the 2 systems be hooked up differently?

Thanks,
Mike

The hydraulic system works by circulating oil continuously. When you need to move a cylinder, you direct the flow of oil into a cylinder and it puts a load on the pump. The pump stays loaded until you either shut off the lever or the pressure gets high enough that the fluid flows through a safety relief valve (like when hitting the end of travel on the cylinder).
In the original eagle hitch system, the hydraulic fluid freely flows from the pump through the control valve and back to the pump. When you raise the lift, either partial or the full flow of the pump is directed to the piston which lifs the hitch, depending on how far you push the lever. Full, unrestricted, low-pressure flow is restored when you return the lever to neutral.
Thus, if you leave the two valves open and try to work the loader, then the fluid is free to circulate through the eagle hitch circuit with little back pressure. This means that you will get almost no flow to the loader valve. Try this: open both valves and fully raise the eagle hitch while leaving the eagle hitch lever in the full up position, and simultaneously try to operate the loader. Once the eagle hitch raises all of the way up, the loader should work normally. This just demonstrates how the system works.
Most tractor hrdraulic systems have a hydraulic priority. Using the valve closest to the pump in the hydraulic circuit will render all of the other valves inoperable until that first valve is released. This is the case with the accessory Case control valve that was intended for the VAC. Denending on your control valves, it might be possible to replumb the hydraulic system so that the loader has priority over the eagle hitch or vice/versa, and eliminate the valves.
It is not a problem with pressure, it is just the way that the system works.

In other words, your system is working like it should. Also, we need to know exactly what you have for control valves in order to advise you on how to hook it up.

That tractor only has 850psi in the hydraulic system. CASE made a hydraulic valve for the VAC that mounted on the torque tube in line with the Eagle Hitch. If you need to run a mid sized loader I'd strongly suggest a front mount pump.

Plumb your pump to your loader valve, the return from your loader valve to the Eagle hitch valve, and the return from the Eagle hitch to the torque tube return. Circuits need to be in series, not parallel. Flow always takes the route of least resistance.
Some loader valves are not designed to take pressure on the return port of the valve. If your loader valve develops leaks it may need to be replaced with a valve designed for "power beyond". Your system is low pressure so you should get by with it.