Water is to warm around here for me to do that. I'd have to pull my scupper plug's.I stick my hand in.
I have tested mine against my far more expensive garmin on my big boat and after a few minutes the through hull reads within 1-2 degrees of the garmin, so either it's close enough or my garmin needs to go in for repair.Fishfinder. Even if you put your transducer inside the hule, the plastic of the boat will warm to the temp of the water. In about 5 mins you should get an accurate temp reading
My Talon is pretty thick walled. I got the Hummingbird 176i kayak kit. It has a rubber mount ring that sticks on the hull and it comes with a tube of marine grade bearing grease you fill with before installing the transducer to get a solid good signal. I really like the mount, it's on there solid so far and no grease is leaking out.The few that I have put in for people are all within a degree. All the boats have been thin walled. Not sure how it would read through the rotomolded boats. They seen to have a thicker plastic. Did you use plumbers goop on the bottom of the transducer to secure it?
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