I am experiencing the same issue and read everything in here on the subject. The videos were great and when I disassembled the unit, it almost went as smooth as in the video.
The pump would not disengage from the motor on my unit, even after removing the screws and springs. The shaft that goes into the pump appears to be rusted. I don't want to force anything and then have to buy additional parts. Has anyone else experienced this? I did give it a shot of wd-40 and let it sit.