Mounting Fish Finder

[Gomphus]

I thought this topic had been covered before, but I can't seem to find it using the search feature. If it has been covered, I would appreciate being pointed at the discussion.

I have purchased a new fish finder for my boat and the transponder will not mount using the same screws as the old one does. So how does one correctly seal the old screw holes? Is it enough to just fill them with Sikaflex or should something additional be done?

For mounting the new transponder, is the correct method to drill the holes, fill them with Sikaflex and then run the screws in?

Thanks in advance.

 

[Gomphus]

I forgot to mention that the boat is fibreglass.

The board won't let me edit the original post.

 

[Last Chance]

Get yourself a countersink drill bit, and run it into the top of each of the old holes. Get some short strand fiberglass filler (ABout 6 bux from canadian tire), and squish it into the larger holes you have made. Sand it flat, and gelcoat if you want to, but otherwise, you are done.

Sikaflex will just fall off if you fill the old holes with sikaflex.

For your new holes, don't bother filling them with sikaflex, just make a nice bead over each hole, and squish your transducer on, then run the screw in, the seal is formed between the Sikalflex and the transom of your boat.

 

[halibutsteve]

Seriously look into bedding the transducer straight to the hull, if you have a place where you can access a flat part of the hull near the back. You will be able to track bottom at high speed, and will never have to worry about fouling your transducer.