Removing A Transducer

[JimLor]

I bought the Garmin 546s GPS and also bought the Airmar P319 transducer. I currently have a like-sized (pretty sure) speed transducer in the hull that I intend to remove and replace with the 319.

Anyone out there have any hard earned wisdom on removing a transducer - if so I'd love to hear about it. Right now I intend to remove the tightening ring; perhaps stick a putty knife under the trim ring (outside hull) and pry a bit; and then take a pipe wrench back inside to try and loosen the transducer. Since I'm not sure how this was sealed (hopefully not with 5200) I may get some of that anti-bond, spray it on and let it soak a bit before I attempt to loosen. If all is right with the world it'll just fall out!

Again, any recommendations, comments, stories are appreciated.

Jim

 

[ed stack]

Hi Jim,

I have a P32, and just recently upgraded from the original 1980 Datamarine to Raymarine. Mounted forward of the keel was the DM speed transducer. Since it was installed some 30 years ago, I wasn't worried about anything like 5200 being there.

When I unscrewed the retaining ring. Just a little movement was observed. With the speed wheel out, I gave the thru-hull a light mallet tap, and it unseated. A few more taps with the mallet and out it popped.

My only thought would be to avoid scoring the hull while trying to pry under the thru-hull fairing.

Hope this helps,

Ed

 

[JimLor]

Ed - thanks for the post. The ST-50 booklet in the owner's binder is dated 1993 and I'm hoping 5200 wasn't used either. This is the speed ducer and I'm hoping the same, with the retaining ring off and plug (the speed sensore is busted and laying in the well) removed I can tell the same story of easy removal as you. I'm thinking I may wiggle it with the pipe wrench and hopefull it will unseat and fall out!

My boatyard guy recommend using Boatlife Caulk to bed the new transducer - what did you use?

Thanks again, all comments are welcome.

Jim

 

[ed stack]

Hi Jim,

We just put in the St-60 set, and i put depth in where the ild DM speed was, and it was bedded with 5200 (back in '80, they glassed the depth under the V berth). I wanted something I was fairly sure to keep the boat watertight.

We had a new thru-hull cut for the ST-60 speed/temp transducer, under the starboard sink, next to the drain thru-hull, also bedded with 5200.

Hope that your plan, which sound good, works well.

Ed

 

[JimLor]

Mission Accomplished

Friday I removed the old speed transducer and it wasn't all that difficult. I ran a thin putty knife between the hull and the flange (exterior) - actually tapped it with a hammer - to break any bond there. I removed the locking nut and put a pipe wrench on the transducer, said a small prayer, and no kidding the transducer spun with moderate force! I tapped the top with a rubber mallet a few times, ran outside and saw a space between the flange and the hull, ran back onboard and banged a few more times and the transducer came out - overall much, much easier than was my imagination forecast.

Saturday I cleaned up the remaining sealant and installed the new P319 transducer with 3M 4200 vice 5200 (faster cure and a better possibility of removing if necessary without knocking the bow off of the boat) and if all is right with the world when we put her in the water on the 30th it won't leak.

Thanks for your comments and suggestions!
Jim

 

[ed stack]

Hey Jim

Glad it all went smoothly. Happy sailing!

Ed

 

[JimLor]

Thanks ed. Put her in the water today no leaks!