I don't have a hand pump, but i do have a short length of (relatively) clean vacuum hose.... I tested mine a while back when going over all of the possible issues. I just used my vacuum from sucking on the hose then "closing" it with the tip of my tongue. I learned this trick from an old GMC I used to have. It's a good way to see if you have smooth operation of the valve and if it's seating properly or not, etc.
Yes, indeed mine would hold open all day if I left my tongue over the end of the tube.
That thing is a bit tricky to get off, especially if the nuts are all rusty. I used the smallest drive sockets I had with an extension (for clearance to the top of the valve) and a 10?mm socket. I tapped it on the nut with a small hammer, and freed them after PB blaster sat on them overnight. I think the new part comes with the grease/gasket (made of steel, methinks) too.
Also, while you have that off of there- clean your EGR ports. On my intake they sucked. They have solidered in plugs in the IM. I tried pulling the plugs, without much luck. I just drilled and tapped them for later cleaning. Someone had a good write up on it on here, I forget who. You basically use a thick grease or motor oil on the bit so the metal shavings don't end up in the intake. Same with the tap.