MSR stove problem.

[Bushleague]

Got a bit of a head scratcher here, my MSR Dragonfly recently quit working. I went through the stove, cleaned jets etc and it still wouldnt work.

Tryed it with a different pump and it works, so a pump problem then. The pump makes pressure, does not leak anywhere, but does not let fuel through to the stove. I took the filters out and still cant get any fuel through, so I took the pump apart... no blockages or other obvious problems that I can see.

So at this point I'm wondering if its got something to do with the little check valve thing at the main valve, but there really doesnt seem like there is too much to go wrong there. I believe hooking up the stove unseats it, and it seats when the stove is disconnected?

Anyone ever dealt with this problem before? Any advice for me?