I know that something is shorting this out, but need a head start. I just rebuilt the impeller in the PSE pump bu every connector was reconnected easily. Suggestions?

If you overtighten the pump housing when you reassemble, it will not allow the motor to turn and blow fuses.

MIkeJ65 is spot on. I had the same issue after cleaning the PSE. I connected it to a bench power supply before install the second time. It allowed tweaking the torque to lower the startup current.