Re-using thur-hull hole?

[Tanley]

Replacing our Data Marine Instruments and have to replace the transducer.

What are the chances the old one will come out cleanly and if it does, is it a bad idea to re-use the hole or should it be glassed over and a new one drilled?

[US27inKS]

As long as there's no delamination and the hole is properly placed and the correct size, then a hole is a hole.

[lancelot9898]

I'm debating the same thing. I have a 25 year old Impulse transducer and display that I'll probably replace with a dedicated Furuno instrument. The installation instructions for the Impulse transducer says to drill a 2 1/16 hole whereas most of the current airmar transducers say to use a 2 inch hole. Not sure if that is significant. Plus there is limited overhead access to the bronze thur hull and not sure how easy or difficult it will be to remove since the boat yard did the work years ago and I'm not really sure as to the caulking used. I'm thinking of putting a pipe wrench on it after the nut is removed and twisting it to break the seal.