Hi this plug flows water when the engine is on. It was hooked to the Speedo when I got the boat. I was not getting correct speeds so I install aftermarket speedo. I sealed off the tube but I not quite sure what it is for. This model boat had a speedo connection in the lower unit which is missing.
My best guess is it might be for water/engine temp?
My best guess is it might be for water/engine temp?
