Ok. I took apart the pump. I found that the main vacuum diaphragm looks okay. But I can't tell if it is sealed where the metal discs are riveted. The diaphragm shaft looks fine and smooth. The shaft oil seal in the body of the pump also looks okay (no obvious tears), but it's in a metal ring and I can't tell if it's leaking there around the perimeter of that seal. Something is not right, and it looks like this can't be rebuilt, so I'm going to remove the vacuum diaphragm shaft, and modify the vacuum portion of the actuator arm and substitute spacers, (if I didn't do that, the vacuum arm would rattle around) and bolt the mess back together.
This allows me to use it as a fuel pump for now.
I'll post pix tomorrow of my hack job of this cruddy pump.
I have another pump that's got to be 40 years old, but all the check valves are staked. Not rebuildable.
I also have a Mercury AC 9682 pump that came on one of my L134's. Not sure why it has a Willys cam arm. But I may rebuild that one at a later time as it has screwed down check valves...I guess rebuildable? It's got a goofy glass bowl off the side too. Sigh. I'll have to re-do all my gas lines.