Mercruiser 3.0L engine differences

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HT32BSX115

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Howdy all,

A friend of mine had a little cracked block (from solidified dihydrogen oxide) action from last winter and decided to replace the engine. He bought a longblock from US Engines in Kent Wa and brought it by today.

The Mercruiser engine is (was) a 1994 3.0 LX 4cyl engine and US Engines supplied a replacement 3.0L engine that has a slightly different cyl head. The exhaust ports on the new engine are considerably larger than the engine that we are removing.

He also bought an intake/exhaust manifold from Napa and it's quite a bit different from the original manifold in that the exhaust ports are quite a bit bigger too.

It appears that the new manifold coincidentally will match up to the 'new' engine but I'm wondering what significant differences (if any) there are in the whole family of engines.

We have the engine out and sitting on the floor. We haven't removed the bell housing/flywheel/coupler yet...... We still have to swap pretty much everything from the old engine to the new one.


Is there anything else we should be looking at and how many different manifolds are there for the 3.0L engines? The carb does match the mounting on the new manifold. and there 5 bolts holding the manifold on the head.


Thanks,


Rick
 

Bondo

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Re: Mercruiser 3.0L engine differences

Ayuh,....

There have been Many heads,+ port configurations in that motor over the years,....
Some of the Largest ports I've seen are on the Old 140hp motors.....
Mixing,+ matching them won't hurt a thing, but the Biggest matched ports would be Better, I imagine.....
 

HT32BSX115

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Re: Mercruiser 3.0L engine differences

Thanks,

It appears that the newer manifolds have slightly larger ports. engine always breathe a little better with bigger ports I guess.... I just wanted to ensure that I don't have some strange setup that can't mix/match.

It appears that everything will go together pretty easily.
 

jswifty

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Re: Mercruiser 3.0L engine differences

Is there any identifying #s on these heads, I'm trying to figure out if this head I have for sale on Ebay, from a 120, will fit a 140.
 

Don S

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Re: Mercruiser 3.0L engine differences

Best to start a new post for your question, not just tack on to the end of an old post. Few read all the replies so they can find a new question.
 
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