Mercruiser 454 cu. in. 300 hp Discontinoued?

[Richie086]

Hi folks,

This is my first post.

I just purchased a used 1992 Doral 255 MC. It's powered by a 7.4 litre raw water cooled engine and bravo stern drive. I want to repower it with a brand new engine, a factory new 454 330 hp engine with fresh water cooling. My dealer tells me this engine has been discontinoued and may have been replaced by a 402 cu. in. 350 hp or a 496 cu. in., but I don't know what the hp rating is on the 496. Also, this 402 engine is supposed to be a 350 cu. in. bored out to 402 cu. in. Can anyone confirm any of this and what my options may be for repowering? Thanks.

 

[TilliamWe]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

7.4 (454) has not been used since 2002.

There is no 402 cid. There is a 6.2LX that is 377 cid. There is the 350MAG MPI. Then yes, there is a 496MAG, that was the actual replacement for the 7.4. But it's lowest HP rating is 375! So in order to satisfy the market of boats that used to use the 7.4l at 300hp, Mercruiser came up with that 6.2LX at 320hp.

 

[TilliamWe]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

A good option that will be less expensive than a new Mercruiser engine is getting a Mercruiser remanufactured engine. In that line they offer a 383MAP MPI. I think it's $7500-ish. My sister bought one to replace a 454MAG in a 90 model cuddy cabin and it does a fine job.
There was just a thread on repowering a twin engine cruiser somewhere on here a few days ago.

 

[Richie086]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

7.4 (454) has not been used since 2002.

There is no 402 cid. There is a 6.2LX that is 377 cid. There is the 350MAG MPI. Then yes, there is a 496MAG, that was the actual replacement for the 7.4. But it's lowest HP rating is 375! So in order to satisfy the market of boats that used to use the 7.4l at 300hp, Mercruiser came up with that 6.2LX at 320hp.

Hi Tilliam,

Thank you for this information. Whether going with the 6.2LX or the 496MAG, would you know what each of these motors might cost new and what fuel consumption would be at cruise speed? Also, would I assume either of these engines would be available optioned in fresh water cooling and would work with this boat? Thanks

 

[joncrisler]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

There are plenty of places that can sell you a new or rebuilt marine 454, ranging from about 300 hp on up. And any of these engines can be fitted with closed cooling- the kits run about $1000 from San Juan, Monitor etc.

For example, a 420 hp 454 marine engine will run around $5000 for the long block. You will need carb/efi, exhaust manifolds and ignition as well.

 

[Richie086]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

For example, a 420 hp 454 marine engine will run around $5000 for the long block. You will need carb/efi, exhaust manifolds and ignition as well.

Thanks Jon. That's another option I can look into.

 

[TilliamWe]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

[Richie, here is the basic link to Mercruiser's engine prices. You can select new or remanufactured from here:

http://www.mercruiserparts.com/Mercruiser_Engines.htm

And this link specifically, will give you the price chart for most everything:

http://www.mercruiserparts.com/mercruiser_gas_sterndrive_engine.asp

P.S. You aren't from in/around Farmingdale, are you?

 

[TilliamWe]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

Richie, here is the basic link to Mercruiser's engine prices. You can select new or remanufactured from here:

http://www.mercruiserparts.com/Mercruiser_Engines.htm

And this link specifically, will give you the price chart for most everything:

http://www.mercruiserparts.com/mercruiser_gas_sterndrive_engine.asp

As you can see a new 496MAG is over $16000! And a 6.2LX is 12,600! A 383MAG is 7995.
But jon is right, get a long block 7.4 and it'll be much more cost effective.

P.S. You aren't from in/around Farmingdale, are you?

 

[Richie086]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

P.S. You aren't from in/around Farmingdale, are you?

Hi Till,

Thanks for all this great information. From looking at those prices, there's no way I'll be able to purchase a new engine. So going with a remanufactured is going to have to be the way I go.

I live in the Port Washington area and purchased the boat from someone that lives here and moored it here too.

 

[havasuboatman]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

You can also buy a rebuilt 454 truck long block, switch out the steel core plugs with brass ones and use the other marine parts from your old motor.
Every Mercruiser 454 engine ever built used the GM 4 bolt main truck block.

 

[picklenjim]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

Why not just have the existing one rebuilt to around 350 hp? It would be easy for a reputable machine shop and probably be under $4000. You would be sure everything would bolt back up also.

 

[Richie086]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

Why not just have the existing one rebuilt to around 350 hp? It would be easy for a reputable machine shop and probably be under $4000. You would be sure everything would bolt back up also.

Hi PicklenJim,

This engine being from 1992 is a raw water cooled engine. Also, this Doral boat had no hour meter that I can find, so I don't even have that information. Reconditioning a motor so old that wasn't fresh water cooled would have me concerned. But whatever I do, the replacement motor will have FWC'ing.

However, I will discuss this with my mechanic. Thank you.

 

[HT32BSX115]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

Howdy,


You also might give USENGINES a call. http://usengine.us/mercruiser.html

They have more than 20 different 454 long blocks that they sell.


Cheers,


Rick

 

[Richie086]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

Hi folks,

The marina where I have the boat gave me a price to remove my old engine and replace it with a factory new (not rebuilt) complete engine, Mercruiser 496 cu. in. with Fresh water cooling and fuel injection for $11,000.00. Obviously this would be a nice upgrade from my carbureted 454 cu. in. , which was raw water cooled.

Can anyone tell me if this is a reasonable price?

 

[Faztbullet]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

This engine being from 1992 is a raw water cooled engine. Also, this Doral boat had no hour meter that I can find, so I don't even have that information. Reconditioning a motor so old that wasn't fresh water cooled would have me concerned. But whatever I do, the replacement motor will have FWC'ing.

However, I will discuss this with my mechanic. Thank you.

You have me a little confused with this as raw and fresh cooled are the same thing, did you mean closed cooling?

 

[Richie086]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

You have me a little confused with this as raw and fresh cooled are the same thing, did you mean closed cooling?

Yes, closed cooling system.

 

[TilliamWe]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

factory new (not rebuilt) complete engine, Mercruiser 496 cu. in. with Fresh water cooling and fuel injection for $11,000.00.
Can anyone tell me if this is a reasonable price?

Reasonable in that the list price for a 496MAG is $16,000? Yes.

Reasonable to spend $11000 on a $9000 boat? No.

 

[Richie086]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

Reasonable in that the list price for a 496MAG is $16,000? Yes.

Reasonable to spend $11000 on a $9000 boat? No.

I didn't know it was only worth that much. I've seen the same year going for $18,000-$22,000.00

What I'll do is talk to my engine builder and have them delete the closed water cooling and only go with the fuel injection and see what that price is.
Thanks.

 

[TilliamWe]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

Okay, even if it's an $18000 boat, spending $11,000 on it is too much to spend.

Deleting the closed cooling won't make much of a difference.

 

[Richie086]

Re: Mercruiser 454 cu. in. 300 hp Discontinoued?

Hi folks,

After much consideration, I decided on a factory new, raw water cooled, Mercruiser 383 Magnum, MPI 350 hp Bravo, 6.3L. stroker with the Smart Craft gauge system.

I really wanted the closed-loop cooling system, but Mercury charges several thousand dollars more for that option. My 1992 Doral 255 MC is in excellent physical condition with all the options available at the time the original owner purchased it. Considering we'll be keeping this boat for a long time, we feel this was the best way to spend the money.

We did have the chance to purchase a used 454 with MPI and closed loop cooling with 800 hours on it, but with one low compression cylinder. However, to have my engine guy rebuild it, for just a little more money, we decided going with factory new was the best option.

Thanks for all the helpful comments from all.