I've mounted my hummingbird down image on my kayak with a thru hull on the transducer, i originally used jb weld to attach it, it worked great, then for some reason it detached i then used another adhesive product and now I'm not getting any readings no down image,sonar,and inaccurate depth was out last weekend and noticed i was in about 2 ft of water and the reading i was getting was 78 ft to 90's now unsure what to do and a little frustrated, anyone out there with some knowledge for me would greatly be appreciated

There have been several folks with the same issue, including me. Somehow the transducer is not making a complete contact with the hull. Even a small air bubble will cause this. I finally gave up on using the "thru the hull" idea and set mine up so that the transducer is actually in the water. If you google the problem, they can explain it better than I can, but they can also show you several fixes for it.

Thru hull mounts can be tricky - any trapping of air between the xdcr and the hull will distort readings. There are several methods to mounting including using electrical duct seal, building a "swimming pool" to hold the xdcr in water or using various mounting compounds such as marine goop......or the best if you can live with it is to mount the xdcr outside the hull so it is in the water - madfrog transducer arm, stern mount, scupper mount, etc. What did you remount it with? Did all the JB weld come off?

Yes all the jb came off, then remounted with marine adhesive goop, I'll have to Google and see what i can find out, worst case scenario I'll have to mount it outside the hull just wasn't comfortable putting holes in my new yak when i first got the DI, i appreciate the help guys, y'all stay safe

After the first hole it doesn't hurt lol . Just make sure of where you want it mounted before mounting I was drilling 1 inch holes the other night setting up my new (to me )graph after being on the water for a few hours found that I got the transducer too far forward and would hit it with my hand when paddling got out the screw driver remounted when I got home filled in the old holes with a soldering iron

get an arm, its way easier imo. and looks cool. And piece of mind knowing its reading true and hulls not screwing with anything.