speedometer

[jmhelm]

I have a 2013 90hp four stroke mercury, my speedometer quit working on me. Any ideas?

 

[Texasmark]

Speedometer really has nothing to do with the engine other than some Mercs have the water pickup in the front of the LU just below the AV plate. If you just ran over a sand bar or mud hole you may have plugged the pickup if it has one. The way you can tell is a 1'8" diameter black hose coming from the front of the lower unit just above the AV plate.

Otherwise, if you have a transom mounted pickup (has nothing to do with the engine) the same thing could have happened.

Take the tube loose at the speedometer and blow compressed air backwards through it to dislodge what may have clogged it. I wouldn't use more that about 20 psig as the hose is not reinforced and too much air could split it.

Mark