Rebuilt fuel pump worked fine before motor rebuild now it is not pumping. It sat in a box for over a year. It was rebuilt with rubber for new fuel. L8 motor. On manually cycling the arm, we could get "some" suction. The fuel lines are clear.

1. Is it possible to put the cam in backward? The arm seems to be on the lobe correctly and I've taken out and put in the pump no less than 10 times.
2. Will priming the bowl help? Required? I didn't need to do so before, but...

thanks
JD