My 94 290 Searay had a transducer (from the factory) shooting through
the hull.

Interesting. I wonder what year they made the change.


He has a 95 310 or something like that. You said he was unfamiliar with
instruments.

Not me, my only post to this thread is my reply to yours.


He should take a second look.

Always a smart idea.


Ps A transducer as you describe is not flush with the hull. Close, but
not flush.

Guess I never really drug my fingernail across it to detect a difference in
height. Sure looks flush at a casual glance. I assume the transducer is
slightly recessed? For what reason? Protection of the transducer? It
would seem that would have the possibility of ever so slightly creating
water turbulence and introducing air to the mix, which would be highly
undesirable. Works great though. In all three cases I've been able to read
triple digit depths (in feet) at 30+ mph.