The trailer has two jacks on it. One is the factory Attwood jack that is welded to the trailer. This jack does not work. It is missing the caster wheel, it will not rotate on the trailer mount and it will not move up and down.
I first sprayed the Attwood jack in PB Blaster then I was able to pry the rotating pin out and start loosening the jack's swinging motion. Next I tried turning the crank to see if the jack would go up or down. Unfortunately the jack just spun in place and did not move up or down. I took the Attwood jack off by removing a big c-clip. To disassemble the jack I punched out the pins that hold on the two gears. This freed up the inner tube of the jack. At this point I could see that the screw the gears turn was seized inside the inner tube. Tonight the jack will soak in PB Blaster and hopefully I can work it free in the morning.