Can you post some pictures of your gears to show us the wear that you are seeing? I changed out the bearings on my bowthruster this past winter for no real reason other than the fact that they were 15 years old. I was surprised with how loose the gears fit together and found that there was a lot of "play" or "slop" in them. However, there was no appreciable wear on the teeth. I sent a video to my surveyor Olivier Beaute showing the amount of play and he said it was what he would consider a normal amount of play.
