Bad Power steering pump?

[FL71C10]

I just put the motor in my truck and got it running in the last two weeks. The truck sat outside for a while before I got it, and there was no ps pump or lines on the box. I am sure water giot into it, and might have ruined it. My motor had ps pump on it already. I hooked it us and the ps lines got hot really fast. I pulled the lines off and I'd like to test the pump to see if it is working. Can I just spin the pulley by hand to make it pump fluid?

Here is what the fluid looked like when I got some out. I filled the pump with fresh fluid before starting it, so I don't think it was that dirty. Looks nasty!