Mercruiser Engine Questions

[TyeeMan]

Hey Everybody,

The boat is 1997, Lund 1950 Tyee Magnum, Grand Sport. It has an Alpha 1 Gen II drive and supposedly a rebuilt 5.7L as of 2 years ago. Incidentally I just purchased the boat this last Saturday. It is the Lund boat I've wanted for ever, practically my dream boat and I finally found it. It's in like new condition to boot.
I wanted the back story on this engine, why it was rebuilt, who did it etc. Well, the dealer couldn't or wouldn't tell me so I contacted Mercury Marine today.

The long and short of it is, Mercury Marine did in fact refurbish the engine (whew, at least it wasn't Billy Bob's Engines R Us) but the guy at Merc said it was not a 5.7L, he said it was 6.2L 383 Mag Stroker Bravo. I'm fine with that! Totally explains why the boat practically jumped out of the water when I did a hole shot.

That said, and here's the questions. I looked at the Merc manuals on Boatfix and no where could I find anything regarding a 6.2L 383 stroker. The only thing I found regarding a 6.2L was a 377 cubic inch.

Is the 383 Mag Stroker Bravo just a Mercury name? Is it a performance "package" you could purchase when buying a rebuilt engine? What kinda horse power am I looking at and will my drive take it?
The engine has a weber 4 barrel on it by the way.

These are just some of the questions that are coming to mind. I'm sure more will come the more information I get.

Thanks in advance for any and all information. Like I said, this is practically my dream boat and I'd like to document everything.

 

[alldodge]

Mercury Marine did in fact refurbish the engine

The 377 is a 5.7 (350) with a stroker crank and a virgin bore. When the 5.7 is bored out to 0.030 over it becomes a 383. Bothe the 377 (6.177L) and 383 (6.276L) are listed as a 6.2 liter. You should have 350 HP and your Bravo drive can take 500 hp easy

The 383 first came into play when folks bored their 350 .030 over and installed a 400 cu in crank shaft (stroker crank).

 

[Scott Danforth]

If the motor is a reman stroker, it could come with a standard bore (377 cubes) or a 0.030 over bore ( 383 cubes) or other. All considered a 6.2

Its a SBC with a 3.75" stroke vs the standard 3.48"

 

[TyeeMan]

Thanks guys. I just found all the information I need, did a little work on the internet. Now the only discrepancy is the block serial number.
The flame arrester cover is not black it's got flames on it. It also has 357 Alpha 4V. I entered that into my browser and the Merc site came up. The engine is Mercury Remanufacturing Plus Series engine. They come from Merc rebuilt (obviously) but they are fully dressed with brand new manifolds, risers, water pump, fuel pump and all the rest of it. The 357 indicates that it is 357 cubic inches or 5.8 liters and they upped the ponies to 275 hp. That would coincide with the Alpha, as the Alpha drive can only take 300hp if I'm not mistaken.

Now, why the serial number on the block calls out a 383 stroker (according to the guy at Merc) I don't know, cuz according to the Merc site the 383 Mag Stroker Bravo puts out 325 hp, 25 ponies too many for my Alpha drive. And it's supposed to be mated with a Bravo drive, not the Alpha I have.

I'll have to double check the engine serial number myself. I just took the serial number the person at the dealership wrote down on the sales agreement.

Sheesh, I feel like Sherlock Holmes.

Thanks again!

Paul

 

[Silvertip]

Just to throw some numbers around: There are 61 cubic inches in one liter. But engine builders tend to fudge just a bit by rounding up or down whether one is talking about Liters or Cubic Inches. And just for fun -- a 3.8 liter engine is also a one gallon engine.

 

[thumpar]

The HP rating doesn't always designate the drive. Even if it is 275hp it could be a Bravo. My 250hp 5.7l has a Bravo behind it from the factory. It is easy to tell by looking at it if it is a Bravo or Alpha.

 

[JoLin]

The engine is Mercury Remanufacturing Plus Series engine. They come from Merc rebuilt (obviously) but they are fully dressed with brand new manifolds, risers, water pump, fuel pump and all the rest of it.

True. Had one installed in my boat 2 years ago and saw it on the pallet before it went in. It comes fully dressed. Only thing my mechanic had to do was swap over my remote oil filter setup to the new motor. It's run flawlessly for 2 years and I still have a year to go on the warranty. It was the most expensive choice for me but I'm glad I did it that way.

My .02