Trouble removing speed transducer thru hull

[CaptainBW]

Admission of stupidity: Last year during launch the speed transducer thru hull leaked, and I removed and rebedded it with Life Caulk. The bad news is that in my haste of trying to get launched (and out of the way of the boats waiting) I did not align the thru hull correctly for the paddle wheel.

So...now I am trying to remove the thru hull to fix last year's error and I am not able to budge it. I have tried twisting it with the plug in place, and using a board and hammer to gently break it free with no avail, but I am concerned about damaging the threads.

Glad to see I did a great job of bedding it last year, but can anyone provide any tips for removing it?

I also considered grinding off the tab on the paddle wheel transducer so that I can turn it and still have it seat properly. Any thoughts on that?


Thank you!

[David M]

Maybe putting a little heat on it might help. Be super careful. Try a hair dryer and not a heat gun. Maybe let the area "soak" with an infrared heater for a few hours first.

There are also solvents for weakening bedding compound but they may not penetrate enough for this application.

Use 3M 4200 next time. It's a nice compromise between a good sealant and being able to remove in the future.

Is there enough room to put a heavy weight on the transducer that will also not damage it and let weight press against it for however long it takes for it to pop loose?

[Donalex]

Yes, I did this.
My transducer is mounted to port and off the centre line. Hunter 376 with a Raymarine log installed by Hunters.
As a consequence it reads differently on port and starboard tacks - so I filed away the registration pip so that I could angle the xducer off the straight ahead line in the hopes I could make it read equally on both tacks.
This didn't really work either.
However I noticed that it is very insensitive to its actual angle so, if yours is only roughly looking forwards then it will probably be okay.
By roughly I mean +/- 20°.

BTW: I needed to replace my echo sounder xducer. They had put it in with Corning 5200. It was so tenacious and springy that every time I levered the flange 1/2" away from the hull it just sprang back again. The only way to break the seal was to put the grips on it from the inside and rotate it regardless of the damage to the threads. It needed a full quarter turn before the sealant was stretched to breaking point. The thread on the xducer was, by then, indeed truly bu**ered.