OK, I have performed the manual adjustment of the brakes on one side of the trailer. First I jacked up the trailer (Port side) and spun the wheels and they were free.
I then pulled the emergency brake actuator; the wheels continued to be able to spin freely. I am now confused, so I pulled the wheels and brake drums. The magnets are worn looking. Not sure if there is a specification for how worn they should be allowed to be. Anyway, I pulled the emergency brake actuator again and tested the magnets with a screw driver; the magnets are being energized. My guess is that they are worn enough so they do not contact the drum and, therefore, actuate the brakes.
So, I put it back together and adjusted the brakes. The brake linings are getting thin, so I need new linings as well, so I am in the process of selecting fully assembled backing plates as replacements.
Do I need to get new drums too?? Or I can get the old ones turned.