Knotmeter Sensor - Clarification Needed

[BubbleHeadMd]

The patient: '69 Coronado 25.

Ok guys, help me out here.
For the first time, I opened up the storage locker under the quarter-berth. Inside, I found what looks like a red, thru-hull plug with a funny little egg-beater thing on the end, and a small cable poking out of the top. I had an odd feeling, and climbed up into the cockpit and watched the knotmeter dial while I spun the egg-beater. Yup, the knotmeter needle moved. WHERE the heck is this thing supposed to plug in??

I have a sinking feeling about this: Under the galley sink, there is a thru-hull for the sink/icebox drain. Right next to that, is a red cap plugging off another unused thru-hull that looks just like the red knotmeter cap except that it has no provision for a wire, and instead has a metal grab-ring. It's just a plug/cap.

Does the knotmeter egg-beater plug in where this red cap is under the sink? How the heck am I supposed to swap them out without flooding the boat?!

It seems that I have a perfectly working knot-meter and no way to deploy the flow sensor!

[anjinsan]

Transducers are generally mounted up forward, under the V birth....the place you put the plug, I mean...It would not work to have the transducer in the galley..it must be afore the keel to eliminate disturbance...look around..at least you got one..some are made to hang over the side on a pole, I hear..good luck

[FrankZ]

A couple of pictures might be helpful, though it is highly possible you have the blank plug in and the transducer out. When you swap them just relax, it isn't as much water coming in as you think.

[Ex-Calif]

To clarify on what Frank said.

It is very likely the red plug is the blanking plug for the transducer. The transducer is removable for those times when the boat is not being used for a while. The paddle wheel can be delicate and get fouled easily.

The "normal" procedure is to pull the plug and install the transducer while "fighting" the incoming water flow. It should only take a couple of seconds after which you mop up the water.

If you have never done this, or if things look "stuck" in any way I would proceed with caution the first time. If you can get on the hard, great. If not you might consider a partner in the water.

The partner in the water has a bung plug in case you can't get the transducer in or the original plug back in.

Another thing you could try is to find something like a toilet plunger and "suction cup" it outside the boat over the through hull. This could dramatically increase the amount of time you have to work.

[senormechanico]

Just don't get transfixed by the wonderful color of the green light coming up through the 2' fountain of water like I did.
It only lasted about two seconds before I came back to reality, but it was way cool !

[BubbleHeadMd]

Based on the info you've provided, this sounds like something definitely deferred until summer. The water is like, 40F here!