mercruiser 4 cylinder 1996

[79Glastron]

Re: mercruiser 4 cylinder 1996

The 3 liter started out life as a 152 cubic inch (2.5 liter) and was later bored and stroked to the 183 inch motor.

The 152 was 120hp and 183 was 140hp.

In the mid 70's there was a big problem with the 140s because of the castings shifting during the pour. No problem for the 120hp but when the block was bored out for the 140hp a lot of times the cylinder wall was to thin, resulting in the cylinder wall cracking open into the water jacket. This happened so many times I lost count but I remember dealing with these at least 5 or 6 times every summer.

Agree on the Saab engine. Automotive engines are not designed to run at 3000-4000rpm at full load all day long. Ain't no coasting for a boat.

Finally somone who knows where the 3.0 came from. Its from the same family of engines as the 194/230/250 inline 6 GM engines, only with 2 cylinders cut off! I believe the 2.5 was a 153, DO NOT CONFUSE this with the 151 "iron duke" two different engines. The 2.5, 153 was used in the Vega, but who remembers those????

As far as performance, you could find an older 140hp head and use that for a 10hp gain. Maybe spend big bucks with roller lifters, and rockers. Shave the head or block and bump the compression ratio higher. Then you would have to burn high octane gas. Bigger valves, custom high flow manifolds, super/turbo charger? But then with the added HP your drive ratio would be wrong and you'd have to get a new gear set......Geez, just get a different boat with the RIGHT engine or repower with something else, it just snow-balls out of control!!!!!

 

[Tail_Gunner]

Re: mercruiser 4 cylinder 1996

i am new user for a mercruiser this season and have only had experiance with outboards before, current boat is a Bayliner 2052 with a four cylinder 130bhp engine coupled to an alpha gen11 leg, no problems with the engine as such runs well but does seem a bit low on power what are the most popular and cost effective mods to carry out on this engine to gain more power, i know swoping to the v6 engine would be good but cost is an issue, whats the max power i can get from the 4 cylinder engine, in the region of 150bhp would be good, your combined help would be most appreciated.

Trim tab's and the right prop, as i sure you already know what cant be done.

 

[JCF350]

Re: mercruiser 4 cylinder 1996

The 2.5, 153 was used in the Vega, but who remembers those????

The Vega engine was different. It was an all aluminum block with a "silicate coated" aluminum bore. piece of junk

 

[79Glastron]

Re: mercruiser 4 cylinder 1996

The Vega engine was different. It was an all aluminum block with a "silicate coated" aluminum bore. piece of junk

Crap, I meant Chevy II...... and postal vans

 

[JCF350]

Re: mercruiser 4 cylinder 1996

Crap, I meant Chevy II...... and postal vans

 

[Bondo]

Re: mercruiser 4 cylinder 1996

also its hard to belive a 3.0l four cylinder engine only puting out 130hp is highly stressed.....god nows how my 200bhp four cylinder 2.0 litre turbo saab manages each day !!

Ayuh,........... That's an Apples,+ Oranges example,.... In the Extreme........

The 3.0l was devoloped to be an Industrial powerplant,....... Nearly 50 Years ago.......

Where as the Saab engine was devoloped Much later for a Much Different application.........

Bondo
I would like to correct you
Full-scale production of the Saab 92 commenced in December 1949
That's 58 years to be precise
but they were making airplane engines since 1938.
I have own a few Saab's to my newest 250 hp Saab Aero with only a 4 cy engine and a 25psi high output turbo , but of course I dont drive WOT
like I do with my 1988 3.0l mercruiser.

Gabe

Ayuh,.......... And I believe that the "200bhp four cylinder 2.0 litre turbo saab" was Not the motor in that 1949 Saab.......
It was probably 1 of those lovely 3 cylinder 2-stroke motors that Saab used up into the 1960s...........

Originally Posted by Bond-o
Ayuh,........... That's an Apples,+ Oranges example,.... In the Extreme........

The 3.0l was devoloped to be an Industrial powerplant,....... Nearly 50 Years ago.......

Where as the Saab engine was devoloped Much later for a Much Different application.........

The 3 liter started out life as a 152 cubic inch (2.5 liter) and was later bored and stroked to the 183 inch motor.

The 152 was 120hp and 183 was 140hp.

In the mid 70's there was a big problem with the 140s because of the castings shifting during the pour. No problem for the 120hp but when the block was bored out for the 140hp a lot of times the cylinder wall was to thin, resulting in the cylinder wall cracking open into the water jacket. This happened so many times I lost count but I remember dealing with these at least 5 or 6 times every summer.

Agree on the Saab engine. Automotive engines are not designed to run at 3000-4000rpm at full load all day long. Ain't no coasting for a boat.

Ayuh,....... You're Close,.........

The 120hp Marine motor is a 153cid,....
Not to be confused with the Pontiac based GM corporate motor, The Iron Duke, A 2.5l, 151cid used in the smaller vechicles,...... It uses a totally different casting,+ a Cross-Flow head.......

And,.........
The 3.0l is a 181cid.........
Which,..Just like the 153cid, 2.5l Marine motor,........

Is from the same family of engines as the 194/230/250 inline 6 GM engines, only with 2 cylinders cut off!

 

[JCF350]

Re: mercruiser 4 cylinder 1996

Ayuh,.......... And I believe that the "200bhp four cylinder 2.0 litre turbo saab" was Not the motor in that 1949 Saab.......
It was probably 1 of those lovely 3 cylinder 2-stroke motors that Saab used up into the 1960s...........



Ayuh,....... You're Close,.........

The 120hp Marine motor is a 153cid,....
Not to be confused with the Pontiac based GM corporate motor, The Iron Duke, A 2.5l, 151cid used in the smaller vechicles,...... It uses a totally different casting,+ a Cross-Flow head.......

And,.........
The 3.0l is a 181cid.........
Which,..Just like the 153cid, 2.5l Marine motor,........

Couldn't remember the exact size so I used my "converter" program and rounded down instead of up.

 

[Bondo]

Re: mercruiser 4 cylinder 1996

Ayuh,..........

I'm just using my Memory,........
And,......
Usually it works about as good as your Program..........
But not This time..........................

 

[gabe1]

Re: mercruiser 4 cylinder 1996

Ayuh,.......... And I believe that the "200bhp four cylinder 2.0 litre turbo saab" was Not the motor in that 1949 Saab.......
It was probably 1 of those lovely 3 cylinder 2-stroke motors that Saab used up into the 1960s...........

Ok
I follow your point so that means my 1988 3.0L merc has the same engine as
a 1957 3.0L?

 

[Don S]

Re: mercruiser 4 cylinder 1996

This thread has run it's course. Time to move on.

Click..........