Help with Transducer hole.

[Facemelter]

OK, here's the skinny.
I bought this bought a few months back, 95 Quantum 170xd and the hummingbird transducer decided it was time to completely fall apart. I am currently replacing it with a Garmin unit 73sv or something. Anyway, I have the hole from the original transducer in the transom that I have run the new cord through. My concern is that I am thinking the hole is below the waterline. When I removed the old one, the hole was packed with what I would assume was white silicon, as it wasnt all that hard and pulled apart like old silicon.

Question. If this hole is below the water line, how do I fill it and seal it up. Not to concerned about looks, since this hole is only a little larger than a half inch.

 

[dingbat]

Doesn't appear to be below the water line. Fill hole with 4200 and cover with clam shell

 

[alldodge]

Looks like boat will be kept on the trailer, and with that:
Either the 4200 or remove the cable, fill with 5200 and drill a hole higher then use silicone. Even better run the cable all the way up and over the transom next to the motor

 

[Scott Danforth]

4200 fast cure or 5200 fast cure, clamshell cover to make it pretty, go boating

 

[Baylinerchuck]

4200 or 5200 takes a little babysitting as it tends to want to drip out of the hole. I have seen plumbers putty packed into wiring holes tightly, then put the clam shell over top. I really like this fix as it is not permanent and does a great job of sealing. Its also reusable.

For permanently sealing small mounting holes, I have had great results using Bondo short strand Fiberglas filler. The only issue is that it is dark green in color so it makes the holes stand out. I typically drill the holes out slightly to get rid of any old sealants, then use a countersink to bevel the edge of the gelcoat. Once filled, you can touch up the Bondo with a little white paint or gelcoat. 5200 works ok too, NEVER use silicon!!! It won't last.

 

[JASinIL2006]

Personally, I don't think I'd trust plumber's putty on a below-waterline hole. I don't think I'd use it on a boat at all, for that matter. That stuff gets soft when warmed. It works great in some plumbing applications, but for the job at hand, there are better materials.

I much prefer the advice to fill the hole with fast-cure 3M 4200 or 5200. If the stuff is too runny, create a dam using masking tape to keep the sealant from running out of the hole, and then remove the tape after it's cured. A clamshell will not only make the whole thing look nicer, but it also provides a bit of protection for the cable where it's bent coming out of the transom.

 

[Facemelter]

Thanks for the info. I currently have a brand new tube of 5200 that I am using to seal the hardware holes for the transducer mount. I want to make sure I am not getting water in the transom.

I have two options. The hole is there, I can use it for the transducer. Run it, and seal it with 5200. Which by the looks of it, is the way I am going to go. Easy and done.
Other option is to seal the hole up with the resin and run it over the transom. Which can require a little more work since I am sealing it for good.

I have spent days looking at cable glands and thru hull connections and making it extremely difficult to figure out what I am going to do. I really appreciate you guys giving me info on this. Really really appreciate it.

 

[DeepBlue2010]

I would use either 3M 4200 or 4000 (I prefer the 4000 for this job). Coat the sides of the hole with thin film of the sealer pushing it inside all wood as much as you can as opposed to just let it float on the sides. Let this cure for an hour or so and apply another thin film. If your finish plate require the wire to pass through, do it now. I use BlueSea Cable Clam 1007100 for this [h=1]Side Entry CableClam with Stainless Steel Dress Cap 100700[/h]

Install the plate temporarily on the out side, jack up the bow as much as you can and go inside the boat and inject sealer generously through the hole. Try to have the wire stays in the middle of the hole as much as you can. Use your creativity, whatever works. I use a small piece of plastic with a U cut in it and I use it to center the cable. I use 3M double tape to temporarily hold it until the sealer cure. It also act as a dam to prevent the sealer from running outside.

When the sealer cures, go out side and remove the cable plate ... do any necessary sealing from the outside ... mask off where you don't want any sealer to go. Have some Acetone for cleaning up afterwards ... install the stainless steel cover ... and that is it. It will look and act as any professionally installed through hole

 

[GA_Boater]

Got any transom drains? Snake the cable through a drain hole. The drain will still work as it should and no chance of stepping on the cable as could happen when it's looped over the transom cap.

 

[dingbat]

Depending on the size of the hole, here is another option. A lot easier to deal with if you need to remove it remove the cable down the road.
http://www.iboats.com/Cable-Thru-Hu...6701504--session_id.304573712--view_id.271122

 

[Facemelter]

Depending on the size of the hole, here is another option. A lot easier to deal with if you need to remove it remove the cable down the road.
http://www.iboats.com/Cable-Thru-Hu...6701504--**********.304573712--view_id.271122

I would still need to 5200 that piece, wouldn't I? I dont see any seals on it. That looks right down my alley. I need to measure my transom thickness though since I have no idea how wide that thing is.