My first time out in the boat this year went well except my depth finder was acting up. I now see why. The sender is flush mounted on the inside of the boat under the motor with some type of epoxy. It must have shaken loose after years of thrashing around. What should I use to re-glue it back to the hull? The epoxy is gray and almost looks like 2 part epoxy. Thanks for your help in advance!
Craig

Craig ,use 2 part epoxy.
Decon or Devon is the manufacture of the stuff I've had good results with.Its sold at True Value Hardware stores here.
Jeff

Most instructions tell you to use a slow cure epoxy.
It allow's enough time for the air bubbles in the adhesive to escape before hardening. Scuff both surfaces good first and wipe clean with alcohol.

I have used 3-M marine grade silicone, I beleive 4200. Much easier to work with. I guarantee that it will not come off if you clean the area reasonably and it will be much easier to manage replacement of the sender if necessary in the future.