Replaced Chopper - Is Pump OK?

I replaced a broken chopper assembly (the victim of a small pit), but want to verify that the pump is OK before putting it all back together. It seems to turn with resistance and makes a bit of plastic-on-plastic rubbing noise, but I can’t tell if the resistance is from the impeller or just back-winding the motor.

Before repairing the chopper, it seemed to drain fine (indicating that the pump/motor was working), but it also sprayed food particles all over the top shelf. Any tips for checking the pump? Thanks in advance.

Carefully look at the white end of the chopper that engages the motor impeller, if worn, replace the motor impeller also. Also, replace the black rubber check valve next to the chopper in the bottom of the pump housing.