Airmar Speed / Temp Sensor Help

[LByers]

I removed my Airmar sensor, cleaned the barnacles and crud off it, and reinstalled it. Now it doesn't give the correct reading. It reads slower--perhaps by half--But I don't know why. I put it back with the arrow pointed toward the bow, but now I'm wondering if I put it in backwards. Any ideas? I don't know the model but the item number on it is 20-399-01.

[richardhula]

Originally Posted by LByers

I removed my Airmar sensor, cleaned the barnacles and crud off it, and reinstalled it. Now it doesn't give the correct reading. It reads slower--perhaps by half--But I don't know why. I put it back with the arrow pointed toward the bow, but now I'm wondering if I put it in backwards. Any ideas? I don't know the model but the item number on it is 20-399-01.

Have a look underneath the hull - don't know why but the brass Airmar through-hull fittings seem to attract barnacles more than elsewhere on my boat, restricting water flow over paddle wheel.