New to Here - Speedometer Question.

[MO_Gearhead]

My speedometer stopped working.

My other (previously owned ) boats had the small tube that went from the lower unit all the way to the
speedometer head/gauge. When I looked at the back of the speedometer on this boat Sea Ray 2000 Sundeck
it has two electrical connections?

I assume somewhere in the line, the tube from the lower drive couples to a pressure sensor(?) which converts that pressure to an electrical signal - which is then sent to the electric speedometer?

Can anyone tell me where that sensor is located on a 2005 5.0L Mercruiser and how to test it?

Thanks!

PS The pickup opening and tube in the lower unit are clear- no debris.

 

[Bt Doctur]

start with power to one side of the gauge. Would suspect the sender is in the engine compartment , most likely transom mounted. might look like the one used for oil prerssure.just a guess.

 

[kohldad]

Not sure on yours, but the Alpha one outdrive has a pin hole on the front of the foot just above the propeller shaft and just to port side of center line. Use an 1/8" bit hand twisted gently by hand to clean out the hole. I would make a twist or two, pull out, clean the bit and repeat. Just had to clean mine out, took about 5 minutes of patience and worry. Eventually, you will hit the end of the trash and the bit will just about disappear.