Instructions from Ocean motions on how to lube the unit. May just be stuck from sitting. They are REALLY high quality motors and I doubt that there is a problem.
Maintenance is fairly simple..remove the two screws that hold the grey motor mount to the black lid.. then remove four screws that hold the black lid to the main body, remove the black lid sometimes the drum comes with it sometimes not ,extract the drum, temporarily put the motor back on to the black lid and if the drum did not come out with the lid then reinstall it below. Holding the motor in one hand rotate the drum to 45 degrees in the other hand to separate the magnets. Wipe down all components, apply Dow Corning 111 to either side of the black lid (you can substitute with KY jelly or Vaseline)though Dow Corning 111 is the best. Re-assemble and you are good to go.