Bow thruster not fully closing

I actually have a "boat-oscopy" camera that I use for situations like this.   

I need it for tight spaces inside the boat as well as looking at things like the thruster doors underwater without actually going underwater.   It displays on my cell phone and has a 25' waterproof fiber-optic cable that I extend under to see the prop, the thruster doors, the cleanliness of the hull, etc.    Works great.

Many times I'll just tape it to an extendible boat hook and use that to get it close.

I don't know if this is what I have (mine is a few years old) but here is something similar on AMAZON.