When you have a resolution I would love to hear what it is.
I've been having the same issue with my bow thruster. It will work normally for several down/use/up cycles, then it will blow the fuse. When the fuse is blown the "at-sea" pin will not go through the hole since the shaft is too high. I had Peg raise and lower it repeatedly and it always lined up with the "at-sea pin". Apparently every once in a while it overshoots and I can't figure out why.
The wire rope raising the thruster is tight and the others loose, as you described yours.