gearheadmike

ok i just got a 77 omc 120 boat engine/stern inline 4cyl i was told its like a chevy? Is it the same as the 2.5 iron duke engine? I was woundering if i could convert it to use it on maybe a homemade rig i could build? idk if a car trans would bolt to this?

tech2

Yes, marine versions are heavy duty, beefier models from what I'm told. Made stronger as they run under load all the time.

BW56

Sweet find. Those things are tough.

gearheadmike

ok sweet lol well i got the whole boat/motor for sale for $300 but if i dont get any bits in a few weeks im gunna pull the motor and mess arund with it. does anyone know if a car trans will bolt to this? And what some of the comon older cars these motors came in?

BW56

chevy ll, and early vegas? some later vegas got aluminum crap if i remember. i have "CRS", cant remember stuff and to lazy to look it up.

Rick Blindheim

This motor was used by Volvo, Mercruiser, and OMC. The differences (as far as I can tell) was that OMC painted their motors blue (what you have), Mercruiser was black, and I don't know about Volvo Marine. The 120 HP and 140 HP motors uses the same GM 3.0 block, just ported differently with the manifolds for the different displacements. They are an indestructible motor to a point. My boat originally had the OMC 140, but the previous owners didn't drain/blow the water out. So after many years of freeze and thaw, not only did the manifold crack, but the cast iron block did in a number of places as well. As long as the block is still good, they can be bored out for more horse power.

Socal Teak J Riley

I'm restoring a boat with this motor. Mercruiser and Volvo both used to sell them in boats. The simplicity of these motors make them very easy to work on.

martin olheiser

Hi do you still have the motor for sale?

Irish_alley

7 years ago

gearheadmike

Holy Crap 7yrs makes me feel old, Side note engine i did sell for $75 so end of this thread.