Whats my 454 Merc???
 

I have a Mercruiser 454 4barrel carb. Trying to see if its a Mag with Rec. ports or peanut. I guess its a Gen VI. Heres my serial #0K282859 I looked everywhere and I guess it can have either one on it. I dont want to remove intake and look at head ports. Anyone know what I exactly have?
Thanks

I have older 454's and this is the site I use but nothing is coming up - maybe because your motor is newer. http://www.castingnumbers.info/site/search/859

My motor shouldnt be that old in a 1998 Crownline w/Bravo I drive just trying to figure it out. I know its a Gen VI

Pull a valve cover and get the casting number for the heads, less work than pulling the intake.

According to this site a mercruiser block with your serial number (minus the 0 in front) is a 96-97 454 mag mpi. http://www.boats.net/parts/search/Me...998/parts.html

But this site says nothing about a mag. https://webapps.brunswick.com/litera...atureSearch.do I would get the block casting number if you can get to it (I am guessing the serial number came off of the carb cover?).

That serial number is a 454 Mag MPI.


454 MAG. BRAVO MPI (GEN VI) GM 454 V-8 1996-1997

0F802350 THRU 0K999999
How about some pictures?

Seems someone has stripped the efi system and replaced with a carb?

Didn't see that. Looks like it said 7.4L Bravo to me.

In your other thread you said that on the top it said 7.4L Thunderbolt. Thunderbolt is the ignition system. 7.4L distinquishes it to be a 310 prop shaft HP cast internal engine. If it were a mag it would clearly say 454 Magnum on top. This is assuming everything is all original as it came from the factory. Also the last year of the carb engine was '97 so it looks like your '98 boat got one of the last carb engines from '97.

You can tell by the intake if its rectangle port or peanut port...pics?

That serial number range doesn't only cover mags. It also covers the 7.4L Bravo carb engines 1996-1997.

Correct I got the serial number off plastic cover on carb. Its not MPI I know that. The serial number can go both ways with Mag or non-mag. The cover only says 7.4/Bravo Thunderbolt ign. on it

If I pull off value cover and get case # of head does anyone know what heads are the rectangle port # and what one is the peanut port case #'s. I also read that in the Gen VI that they also put on that Gen. that are not rec. or peanut, but a larger intake ports then peanut but not as big as rec. they make it so confusing.

Ok?

I don't know of merc ever labeling a mag engine a 7.4l, looks to be a 330

Do you have access to the boat or are we gonna guess all winter?

Is the mercruiser metal stamped tag still on the block? Located on the starter side on the bell housing flange.

I do have access to boat I can check out metal stamp on block that would tell me exactly ?

Something seems funny with the carb to me. Could be that the whole engine has been modified or replaced? You cannot rely on the carb cover IMO. And I am not sure the block casting number is going to help (I thought the block was the same and the internals with the internals - cast vs forged where the difference?). If you get a shot of the intake for these guys they will be able to tell you of it is a rectangle port intake from looking at it.

Where did you see that? The serial number only pertains to one engine. Every place I check the number it comes up as 7.4L Bravo. As bus said the mag was never labeled as a 7.4. Here's some specs comparing them.
http://www.perfprotech.com/blog/arti...specifications
Accordind to this the 7.4L should have a cast iron intake manifold and the mag has an aluminum one. Take a magnet out and check it.


Type your number in here and see what comes up.
http://www.perfprotech.com/mercruise...r/searchserial

That will tell you if the number on the plastic cover is correct.

Not talking about the block casting number. Talking about the serial number on the steel tag mounted down by the starter.

What is unusual about the carb?

Number comes up as a 1997 7.4L carb engine.

+1

My 1998 checkmate 242 convincor had a 7.4l 330hp engine with a weber carb.

The carb Mags had an aluminum high rise.

Yes. bring a rag to clean . I've had to use my phone before to video it but it worked. Its a little metal tag says mercruiser and the number stamped.

A picture can settle this very easy instead of everyone guessing, you can tell the difference by looking at intakes, pic?????

the engine as sold/built was TBI(7.4 TB5) sold in 98 and had MPP to 03(extended warranty) tbi probably crapped out and switched to carb, cheap and simple. check carb numbers and specs to make sure setup your engine.

Thanks for all the help I am going to try the magnet idea if its cast or alum then that should tell me what I got correct? If not I will pull valve cover I guess. What I'm thinking on doing is putting a supercharger on it but I will only put it on if there rec ports not peanut heads

Guy on my lake just completed his 5th season running 5lbs of boost, 177 blower to a peanut port 454. Even used a rect blower intake!

He got 10 mph and 150 hrs so far

not always, my stingray had a 310hp 454 bravo 3 package, the 310's had mag motor intake and carb, peanut port heads

they put a rec. port intake on peanut heads from the factory??? that woulda had to be good for flow hitting a huge wall like that...

it makes no sense to me but they did it! there is a thread on here somewhere about merc crossbreeding intakes

They sure did. They were on 7.4L "Performance Tuned" motors with Bravo III drives.

So stupid.... but oh well... lol

Where did you find this information? Can you share a link to it?

Every place I have looked comes up as a '97 carb engine including the Mercury site.http://www.mercurymarine.com/parts-a...parts-catalog/
Launch catalog-enter serial number OK282859 -select "engine" catalog-click down arrow in drop box above parts list. You will then see all the catagories of parts for that engine including carburetor.

A cover that says 7.4/Bravo is a non-Mag.
Mags have aluminum GM hi rise intakes, and MOST non-Mags have cast iron low rise intakes. NO MAGS have cast iron intakes. If a magnet sticks to it, it is DEFINITELY NOT A MAG. If the magnet falls off, then it MIGHT be a Mag, but not necessarily.

MC

:party-smiley-004:

Picklejim
If you put in my serial # it comes up with mag heads and bravo heads in its parts list so that why I'm confused

Hey Spooln, you posted this same question on another forum, which I looked up for you. However the serial number you posted there was ok282585, which is a carbed gen VI 7.4L. Which number is correct? The number you posted here, ok282859 is indeed a TBI 7.4L.

Bob Lloyd

bobl 585 is correct one. I know its a Gen VI 7.4l Carb wanted to know what heads are on it. I get different listings for heads might be rec. or peanut heads

Simple. After you type in the serial number the next screen will come up saying it's a "Gen6 7.4L Bravo". If it were a mag it would say "Gen6 454 Magnum Bravo". Diagram is used for both models. In the list it shows 2 listings for heads. One says 454 Magnum and the other 7.4L Bravo. Beings this serial number comes up as a 7.4L Bravo then it would be the heads listing which says 7.4L Bravo after it. By the way both serial numbers that Bob L listed come up as the same engine, model 474B110KS carb engine.

Bob, I come up with both of these serial numbers being the same engine model, 474B110KS which is a carb engine. Sure your not confusing it with TB5 which is Thunderbolt 5 Ignition? Can you post a link to where you seen this?

Oops, my bad. You are correct they are both the same carbed engine. I'm a Merc dealer and looked it up on product history. I just had TBI on the brain after seeing the conflicting serial numbers and other post about TBI. But to answer Spooln's question that is definitely a peanut port engine. It used a GenVI roller cam short block, but the peanut port heads as opposed to the Vortec heads on 1998 and later 7.4L.

Bob