haha
well here's a picture of the hard metal line that i removed. it appears to me to be just a simple angled pipe to connect the pump to the hard rubber line which then feeds the whole vehicle it's vacuum.

But i had taken it off thinking it was the piece described above by you regarding only blowing one way.
Is this the piece that should only blow one way?


When i had done the last test i'd just mentioned, i was connecting the mighty vac directly to the top of the pump where this line used to connect.