Have a Bayliner Runabout with a busted AQ120a engine, looking at replacements, any recommendations?

[saeeur]

Hi all,
I'm refurbishing an old 85 Bayliner Runabout I got for peanuts. It's got an AQ120a on with a 270 outdrive and I want to just put a new motor in it.

I'll be totally honest this would be my first time doing this on a boat. I don't think I should limit my options based on the existing outdrive either as it has a 2.15:1 gear ratio, but I also don't know how realistic it is to simply replace it with a new outdrive on a different ratio.

I'm just wondering what would be a good replacement motor in terms of availability and viability (something like a volvo penta 4.3L?), and what problems I'd expect.

 

[goatman1]

the gear ratio of the leg matches the motor, you probably have a 2.16to1 ratio. if you put a 3.0l merc in there the exhaust pipe will be on the opposite side. i deleted the exhaust from the leg and went out the transom and plated the exhaust hole on the transom shield/ then in order to use a certain prop, had to get a hub kit that required the prop shaft to be drilled and tapped and once that was done the exhaust port flapper housing was in the way of the prop so i just deleted that as well, not to mention a new location for motor mounts because the fresh water pump runs off the front crank and the motor mounts were in the way of the mechanical fuel pump so needed an electric fuel pump. everytime i solved one problem another would appear, i do this as a hobby and like doing this sort of thing. if your transom is rotten and needs new plywood and fiberglass work id be tempted to go with an Alpha leg. ive never worked on one or owned but there were countless times that i thought this would be so much easier with an Alpha leg.
if you can go and rip EVERYTHING from motor mounts to wiring harness and the leg out of a boat its still alot of work compared to maybe just replacing the existing aq120a with another aq120a and doing the primary drive shaft bearings while you have the motor out