4.3 Mercruiser engine swap for Chevy 4.3

[wannabeskipper]

Hi all,

I just recently joined iboats but I have been reading your forums forever trying to get information on swapping my Mercruiser 4.3l cracked block for a Chevy 4.3. I have read about the parts that need to be changed. I know I have to change the freeze plugs and I have all the other parts from my old engine that are still usable. I was just wondering I have come across an engine from a Chevy Astro Van with about 80,000 miles on it. The guy that has it says it ran fine before he pulled it. I was hoping this would be my chance to do the swap. Will this engine work to use the block off of? Is 80,000 miles okay? Also, I do not have a truck but can put the old engine in my Ford Expedition to haul it home. I know it is a little off subject but I was hoping someone could comment on that too.

Thanks

 

[delta229]

Re: 4.3 Mercruiser engine swap for Chevy 4.3

Just from a technical point of view, there are several differences in marine engines. Cam duration and lift is one, among others. In the Chevy style, the engine has oil baffles below the crank to keep the oil pump fed with the bow high. I recently did a block change on my 350 Chevy Bayliner and found a re-manufactured marine short block with a warranty for less than a grand.

 

[sptjet90Reflexx]

Re: 4.3 Mercruiser engine swap for Chevy 4.3

take the block from the chevy 4.3 and put all the marine parts on it. Cam,exhaust,intake,carb all of it. Also you should probably change the freeze plugs to (I think) Brass?

Don't see why the engine wont fit in your expedition. use old tires and sit the engine on that. should provide enough clearance for the oil pan. getting it in and out will be hard though...

 

[Bondo]

Re: 4.3 Mercruiser engine swap for Chevy 4.3

Hi all,

I just recently joined iboats but I have been reading your forums forever trying to get information on swapping my Mercruiser 4.3l cracked block for a Chevy 4.3. I have read about the parts that need to be changed. I know I have to change the freeze plugs and I have all the other parts from my old engine that are still usable. I was just wondering I have come across an engine from a Chevy Astro Van with about 80,000 miles on it. The guy that has it says it ran fine before he pulled it. I was hoping this would be my chance to do the swap. Will this engine work to use the block off of? Is 80,000 miles okay? Also, I do not have a truck but can put the old engine in my Ford Expedition to haul it home. I know it is a little off subject but I was hoping someone could comment on that too.

Thanks

Ayuh,.... Welcome Aboard,.... Generally speakin',... Ya that'll work,.....

The Chevy truck motors are nearly carbon copies of the Chevy boat motors,...

But,.....

You've made No mention of the Vintages of these motors,....

The 4.3l has gone through massive changes over the years it's been produced,...

Vintage is Extremely important,....

'n it's brass Core Plugs,....

 

[wannabeskipper]

Re: 4.3 Mercruiser engine swap for Chevy 4.3

Ayuh,.... Welcome Aboard,.... Generally speakin',... Ya that'll work,.....

The Chevy truck motors are nearly carbon copies of the Chevy boat motors,...

But,.....

You've made No mention of the Vintages of these motors,....

The 4.3l has gone through massive changes over the years it's been produced,...

Vintage is Extremely important,....

'n it's brass Core Plugs,....

The engine from the Astro is a 95 and my boat engine is a 96. Since the years are really close I assume that they will work?

 

[Bondo]

Re: 4.3 Mercruiser engine swap for Chevy 4.3

The engine from the Astro is a 95 and my boat engine is a 96. Since the years are really close I assume that they will work?

Ayuh,.... '96 was a change-over year,...

Ya really need to Check the number of bolts holdin' the intake to the heads on Yer motor, 'n whether the starter bolts are Straight across from each other, or Staggered a few inches,...

Then of course, yer Donor motor needs to Match what ya find on Yer present motor,....

If those 2 things check out, it should be a drop-in, plug, 'n play operation,....