I put some light marine grease inside the housing and some behind the keyway to hold it while I slid the impeller on. Then I spun the drive shaft a few
It's been cold and wintry here lately and the boat is out of the water. I haven't done anything to it since I replaced the plug.
You may have a bad EMM.
What did you lube the impeller with a little vaseline or dish soap works good until you get water flowing through. Maybe dunk it on a barrel of water