any one know anything about mercury 3.4 outboards pros and con please

I had one...getting hard to find parts for, and they are maintenance intensive..stay away if possible. Very heavy engine and very thirsty.

Just curious. What year was these engines, and what kind of power?

they were problematic from new....they dont like to be spun up past 5k RPM and parts no longer exist basically.....

is this part of a package or are you considering buying it to hang on something you already own?

hanging it on something the motor is new never fired still in crate

the good 1's had a cogsworth block.

mine was a Cosworth I think they were 1991 on or so..still had issues all the time...stay away!

Is this the 275 hp motors from 91-93ish with the 76 degree v6?

yep, Merc cast there own blocks from 1988 to 1990 or so then they were cast by Cosworth till 1993