In my case, I did not remember to bring up the bow thruster until I was out of the harbor and in about a 4 foot chop, and the extra wave motion when I did bring it up caused the tip of the shaft (the tapered bit) to jam on the ring that is meant to guide the shaft up the last few inches.  The lifting mechanism kept trying to complete the task until the fuse blew.  Of course I did not have a spare fuse on board (it is a simple 10 amp car fuse) so my First Mate jury-rigged a solution with a piece of wire until I was able to get a replacement.

Try as I might, it is amazing to me how often I forget to bring the bow thruster up before increasing speed above a couple of knots.  I have resorted to appointing a crew member to remind me - then for their trouble they get to go forward and disarm the bow thruster and pin it up. 

Are you the original owner of Kimberlite?  If not, I wonder if the previous owner removed the fuse holder and shorted the connection for some reason.

Derick

SM2K #400 Brava