4.3 mercruiser engine replacement

[Nrizzo20]

Hey everyone,

I have a 1993 4.3 mercruiser. I found out last month my motor is blown after a few weeks of buying it. #6 cylinder has a deep knock. I pulled the outdrive and today i pulled the engine. Gimbal bearing and u joints seem to be fine. Although I am going to replace them seeing it's all apart anyway.

I have a good amount of experience wrenching with cars and bikes, not so much marine. Any advice on what you guys think I should do? Short block prices run around 1300-1400$$ and long blocks about 1800-2200$$. I already had the top end off where I replaced everything but the heads.

So, best remanufacturing marine company to order from?

And what else do I have to exactly replace? Coupler, manifolds, gaskets? I don't mind putting the extra hours into it so save some big $$! Thanks for the help!!

 

[Bondo]

Ayuh,.... Bein' a '93, I'd go for a post-96 Long block crate motor with Vortec heads,....

Think Truck motor, insteada boat motor, it'll save ya some money,....
A Truck motor, with brass core plugs makes the perfect boat motor, without the Marine price tag,....

 

[achris]

Ayuh,.... Bein' a '93, I'd go for a post-96 Long block crate motor with Vortec heads,....

Think Truck motor, insteada boat motor, it'll save ya some money,....
A Truck motor, with brass core plugs makes the perfect boat motor, without the Marine price tag,....

And head gaskets... Just get a truck 4.3, replace the head gaskets and core plugs, bolt on all the marine fruit and veg from your existing engine and you're good to go....

 

[Nrizzo20]

Ayuh,.... Bein' a '93, I'd go for a post-96 Long block crate motor with Vortec heads,....

Think Truck motor, insteada boat motor, it'll save ya some money,....
A Truck motor, with brass core plugs makes the perfect boat motor, without the Marine price tag,....

Thanks for the reply, and any good company's I should order a long block from?

 

[Nrizzo20]

And head gaskets... Just get a truck 4.3, replace the head gaskets and core plugs, bolt on all the marine fruit and veg from your existing engine and you're good to go....

You think I should get just a used 4.3 truck motor and put on my marine externals?

 

[achris]

yep. and change the head gaskets and core plugs.

 

[birddog001]

new to forum.i have a 4.3 liter v6 in a 1988 searay.
can i install a newer 4.3 with vortec heads.will the exhuast manifolds still work.i just bought boat as project and engine has water in it.looks like boat engine was submerged.i took heads off and got crank and pistons moving again.oil had signs of water contamination.i fear bearings are damaged

 

[Scott06]

new to forum.i have a 4.3 liter v6 in a 1988 searay.
can i install a newer 4.3 with vortec heads.will the exhuast manifolds still work.i just bought boat as project and engine has water in it.looks like boat engine was submerged.i took heads off and got crank and pistons moving again.oil had signs of water contamination.i fear bearings are damaged

Best to start your own thread or ask the mods to move it to a new thread...

Yes you can go back in with a vortec motor. Exhaust manifolds are the same but need to check if yours are not cracked given other issues. Will need a Vortec intake as well. Can get a '96 and up truck engine swap marine head gaskets and brass core plugs , and you have a marine engine...