Does anyone know whether splicing transducer cable is a no-no? I busted one of the paddle wheels on my speed/temp transducer. It was painted when I bottom-painted this spring, a little over zealous paint application and when I tried to free it, one of the paddles broke. I guess I could have glued it back with some of my wonder glue..but it's too late now. I don't want to run another cable to the bridge, it's a bxxxx of a job. The assembly can be replaced from inside the boat and I would love to be able to splice in the new unit on existing cable.

I just copied this from the iboats forum:

I've already replaced my transducer with a new one but, for your info and reading pleasure here's what they say.....Transducer Cable Splicing Instructions. Lowrance does not recommend cutting and slicing of transducer cables. The connector ends are injection molded onto the cables and the transducer body housings are potted with an epoxy material to make this accessory completely waterproof. Water infiltration in this cable can cause delaminating, internal corrosion, and cable damage, which can result in poor performance at the least - and sounder malfunction or damage at the worst. If a cable is cut or broken we do provide some accessory connectors which are preferable to splicing if the cable remains long enough to reach. However if the cable is too short or a connector kit does not exist then you should follow these instruction to splice the cable. This procedure is best performed by a reputable and skilled electronics repair facility or technician. Cut the cable in a location that will place the splice in a protected area in the vessel. It should not be exposed to rain or spray, nor be allowed to lay in the Bilge or other area which will allow it to be submerged in water. If using a “heat shrink” insulating material, for either the center conductor connection, shield connection, overall splice, or all of the above, place over the cut ends now.Carefully strip approximately 1” of the outer insulation or jacket from the ends to be spliced. Unwrap the shield and twist it as shown below. Strip approximately 3/8” of the inner insulation (center conductor) from each end to be spliced. Twist the center conductors of the two ends together, then solder the connection. Use special care to allow full flow of solder without damaging or melting the insulator around the center conductors. This can result in a shorted connection and damage to the sounder. Wrap the solder joint in good quality electrical tape or heat shrink as appropriate. Twist the shield wires together and solder this connection. Wrap a small piece of Aluminum Foil over the entire splice. Make certain the foil makes a good contact with the shield wires to prevent, reduce, or eliminate electrical noise or interference. Finally wrap the entire splice with electrical tape or use the Heat shrink material previously installed to completely seal and insulate the splice connection. The transducer is now ready to use. If we can be of any further assistance please contact us. Lowrance Customer Service 12000 E. Skelly Dr. Tulsa, OK 74128 Customer Service: 1-800-324-1356

The unit I referred to is the speed paddle/temp sensor. The depth xducer is mounted separately. I really could have freed the paddle wheel the correct and easy way, from inside the boat. But no...old numbnuts had to force the thing and is paying the price. Since I posted and with the replies above, I have concluded I can carefully splice in the new sensor as long as I mount the splice in a dry place (not in the bilge soup) and, per Airmar, use their junction box. Mind you, neither the temp sensor nor paddle wheel is essential. I can get the speed from the GPS and temp by sticking my finger or toe in the bay. And, frankly, does it matter - the bay is warm in the summer and frigid in the winter.

If the depth transducer doesn't have speed and water temp, then it is likely fed by a coaxial cable. You can get plugs and jacks for this, and I like to have a break in the cable at the top of the bilge so that the transducer can be taken to a shop for testing. The manufacturer can tell you what the cable is, and you can get a solder-type plug and jack for it. I would not use the crimp type.

I imagine that the cables for the multipurpose transducers are simply a coax cable with a couple of wires also, but I have never had one.

Thnx all for the info and Jim, for the tool offer. A quick check at Airmar shows they "bless" splices but state they won't warrant the replaced end unless one uses their junction box. A look back at my original post shows it was a bit unclear. It's just the speed/temp sensor of an Apelco 560 (Apelco is now Raymarine). I will try the splice without the junction box and wrap it nice and securely and if it quits in the future, well I will just have to use the hourly water temp readings the govt gives for free at Thomas Pt Light. One can dial the automated reading on a cell phone and get current wind direction/speed/air temp/water temp/barometer. By the way, if you have one of those buoys in your neck of the woods, there's a good chance it, too, will give automated readings via phone. More on that in a different post.
Meanwhile, I will let you know what happens after I buy the replacement speed paddle and splice it in.