transducer installation question

[aknoxclark]

i just acquired an '07 21 SE and i want to add a GPS/Depth Sounder combo and will likely need to replace the current transducer attached to the transom. my question is if new holes need to be drilled into the transom or even if i use the current holes for the new transducer, how should i prep the holes before installing the screws to insure no water entry? just fill with the 3M 5200, reinsert screws and all is good to go? although i see the value in parker, grady white, other top notch boat manufacturers still using wood, i remain a bit paranoid about attaching new equipment, other that requires screws....thank you!

 

[xmako]

The last time I attached anything to a transom I did exactly as you said, attached the screws with a generous coating of 5200. No transom/screw related issues with that boat in the 10 years I have had it.

 

[ultrasport]

Exactly what you said but i would use a slightly larger diameter stainless screw and coat screw head w 5200 as well

 

[aknoxclark]

many thanks to both of you.