I have a 16' square stern canoe and thinking about a long tail 6 - 6.5 hp to get shallow, but also want to use it for photo shoots of birds, how fuel efficient would one be? How quiet? Ran jets and outboards but won't work on this hull. Any thoughts?
Thanks

I ran a 6.5 for a few years for hp restricted lakes. They are pretty fuel efficient, bring an extra gallon gas can with you until you get a feel for it. I had a honda GX200, it was probably as loud as a 2 stroke outboard. Sounded like a push mower.

I mount 7 HP subaru motors and they run for 1 hr flat out. longer if there is a lot of simple nosing around and just looking rather than traveling.

Mark F. Cheney

I run a 6.5hp Briggs /Go-Devil on a Gheenoe HiSider 15'4". Your canoe will probably be tippier than a Gheenoe so be careful.
Carry a spare gas can if you're worried but they don't use much gas. It's as noisy as any air-cooled lawnmower engine.