Ford 420 rear hydraulic pressure test

[Blase-On]

I have a ford 420 (70s?) that the rear three point lift arms stopped working. I changed the fluid but seems to be leaking out of the brake pedal shaft but that’s another problem, I guess. Is there a way to test pressure to see if the pump is working before I lift the cover and checks the piston and valves? I haven’t been able to find the same configuration online. Attaching a pic of what I have.

 

[Sean in PA]

The large bolt at the front center of the small plate under the front of the seat is a test port. You can plumb a gauge there and chain the lift arms down to test the pressure as you raise the control handle, but if the arms aren't moving, there likely won't be any measurable pressure at the test port. That doesn't mean that the pump is bad. It is just as likely, or even more so, that the unloading valve is stuck open, or possibly the pressure relief valve, but that is less likely.

 

[Blase-On]

Thanks. Looking for the parts before I lift the cover, I only see this safety valve. Is this the relief valve and there is a separate unloader? I Couldn’t find that part.
Or is the unloader the valve controlled by the lever?

 

[shaun wallace]

The system relief valve is below step on rite side.

 

[Blase-On]

The system relief valve is below step on rite side.

This!?

 

[shaun wallace]

This!?

Yep Thats it.