speedometer not working

[TBird]

I am getting no reading on my speedometer. Any idea what might cause this? Fortunately I am having the boat hauled in two weeks for bottom paint and some repairs and can have it examined then, but would like to know the range of possibilities in advance. Thanks.

 

[David Morgan]

Mine went out as well. The reason was I hit a piece of wood and a portion of that wood lodged itself inside the small hole on the leading edge of the outdrive that uses pressure to determine speed. I cleared it out by hand turning a drill bit. The wood came out but it still does not work. I'm curious to hear what the other possibilities might be.