Yamaha OX66 250 HP No Speed or Distance

Patsy Mac

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My Yamaha 250 stopped indicating speed and distance covered. Any clues on how to troubleshoot? Guage still indicates 18 miles, but never increases. Worked fine until recently. :doh
 

Fishtales

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The is a little speed tube that determines speed by the amount of water that runs thru it. They often get clogged. The tube is called a pitot And it should be located on the front of the gear case (lower unit). Use a small piece of wire and rotate in the tube and try to putt l
Out the debris. This is the likely cause.
 

seasick

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Yes probably a plugged tube or pilot hole.
Water doesn't actually flow through the tube. It is the water pressure, not the flow that operates on the sensor located in engine cowling.
If water flows, that is a problem.