When replacing the rubber impeller, what is the correct method to use to ensure the blades of the impeller are facing in the right direction?
I am sure I have the impeller on wrong.
In additon to what Crem said, turn the driveshaft CW (looking down the driveshaft), while seating the Impeller housing over the blades. That is the direction the motor turns.
Just look at the old one when you remove it and put the new one with the blades turned the same way. A little Vaseline or dish soap will help. As stated above, it will correct itself when running.