New Cobalt 23LS

[Roccafellas]

Hello,

My names Jordan. I own a mechanic shop up in Sudbury Ontario Canada.

I recently just purchased this boat. Link below. I pick it up this weekend. It’s always been stored and serviced since new (I believe) at Walkers Point Marina in Ontario.

Just looking for any insight or quick directions or input anyone has about this boat.

The add says it has a Mercruiser 7.4L….. What are the odds this thing has a MAG? With no pics either I’m really hoping this thing has MAG.. If not a camshaft is definitely in the future with supporting mods. I’ve spent 2 hours searching google and youtube and can’t find a thing on if this 23LS had an option for a mag. I see 5.7’s and 7.4L Volvo.

Last question. I want to do a thru hull exhaust. Is there a write up someone could just direct me too quick or is this possible? Thanks.

Jordan. https://www.kijiji.ca/v-powerboat-motorboat/mississauga-peel-region/cobalt-23-5-for-sale/1654152043

 

[04fxdwgi25]

Only way to know is get the engine serial number and look it up. The label on air cleaner cover will say 454 MAG, if it is. But chances are, it isn't.

The 454 MAG has a lot of forged parts inside where the 7.4 has the cast parts, generally. Heads usually different, too.

Don't be too hasty on making mods to engine. My old 2550 Chaparral had a 7.4 w a B1 and was 55 mph runner. You might be surprised. Also, that boat has a Bravo 3 and if you make jump in HP, those props are big $$$$$$ to change to get the rpm right.

Suggestion: if changing cam, use only a marine one. Automotive ones are poor choices for marine application, as the long overlap has a bad habit of sucking in water.

 

[Scott Danforth]

there are about a dozen companies that do a complete thru-hull. however Corsa is probably the better supported brand.

I would just use the boat as is. the ad says its a 60mph boat

 

[tpenfield]

EDIT: The engine is a V-P 7.4 Gi as shown in the video. . . https://www.google.com/url?sa=t&rct...usg=AOvVaw2XOhAZWTuqIFKBKEkaFBmW&opi=89978449

Be careful about cam shaft upgrades, because of the wet exhaust. The cam on those engines have very little valve overlap for a reason.

 

[Roccafellas]

EDIT: The engine is a V-P 7.4 Gi as shown in the video. . . https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwi15vPXmNT_AhW-L1kFHcTHCZwQFnoECA0QAQ&url=https://pubs.volvopenta.com/publications/7740288&usg=AOvVaw2XOhAZWTuqIFKBKEkaFBmW&opi=89978449

Be careful about cam shaft upgrades, because of the wet exhaust. The cam on those engines have very little valve overlap for a reason.

Hi there, the engine is a Mercruiser not a Volvo Penta

 

[Roccafellas]

I just got off the phone with the Marina all they could give me is model number B17.4L MPI

 

[tpenfield]

Hi there, the engine is a Mercruiser not a Volvo Penta

OK, so the video in the advertisement is not the exact boat, but similar.

Usually in Mercruiser 'speak' the Magnum engines are labeled and referred to in cubic inches. So, a 7.4L Magnum is usually referred to as a 454 MAG.

So, it is a good assumption that it is the standard 7.4L oval port intake engine, is in the range of 310-330 HP, and probably has the MEFI-1 controllers. I had 2 of those in my last boat (twin engines). They were fine. Gen 6 GM 454 base engine with the big aluminum intake plenum.

The 454 MAG version has the rectangular intake ports on the heads and is good to about 5,000 RPM . . . has about 365-385 HP (IIRC) , whereas the standard 7.4 tops out at about 4,600 RPM.

 

[Roccafellas]

Hi there, the engine is a Mercruiser not a Volvo Penta

It is a B17.4L MPI as per the marina not sure if that makes any difference.

 

[tpenfield]

It is a B17.4L MPI as per the marina not sure if that makes any difference.

No difference . . . Bravo 1 outdrive, 7.4L MPI engine. In the 1996-97 time frame the 7.4 and 454's were the GM Gen6 version, which used roller cam/lifters. Better than the Gen5 IMO.

 

[Roccafellas]

No difference . . . Bravo 1 outdrive, 7.4L MPI engine. In the 1996-97 time frame the 7.4 and 454's were the GM Gen6 version, which used roller cam/lifters. Better than the Gen5 IMO.

Thank you kindly Sir. I called again. I have the serial number where would I be able to input it and find out if it has a 454mag or not. I asked the seller he said if that’s an option that they chose the “biggest engine” available. Pics attached of serial number.

 

[Roccafellas]

OK, so the video in the advertisement is not the exact boat, but similar.

Usually in Mercruiser 'speak' the Magnum engines are labeled and referred to in cubic inches. So, a 7.4L Magnum is usually referred to as a 454 MAG.

So, it is a good assumption that it is the standard 7.4L oval port intake engine, is in the range of 310-330 HP, and probably has the MEFI-1 controllers. I had 2 of those in my last boat (twin engines). They were fine. Gen 6 GM 454 base engine with the big aluminum intake plenum.

The 454 MAG version has the rectangular intake ports on the heads and is good to about 5,000 RPM . . . has about 365-385 HP (IIRC) , whereas the standard 7.4 tops out at about 4,600 RPM.

Very good information thank you. Ah. Wish it had the mag. Less work for me. From research I see don’t even bother hopping up the 7.4L and just save for a 502. Any chance anyone can look at the serial number and know where to call or input it to decode?

EDIT*** Upon research all above posts are right. It doesn’t say 454MAG just 7.4L MPI. Oh well. Guess I’ll save for a 502. Or trade it for one next summer.

 

[tpenfield]

Serial # 0K147398 comes up as a Gen5 7.4L

https://www.perfprotech.com/mercury-marine-parts-catalog/search#/diagrams/folder/24554328171979

 

[Roccafellas]

Serial # 0K147398 comes up as a Gen5 7.4L

https://www.perfprotech.com/mercury-marine-parts-catalog/search#/diagrams/folder/24554328171979

Thank you Sir. I realize it is not a Magnum. Hoping the thru hull will still sound somewhat good. Lol.

It being a Gen V LX does the X signify anything if importance? From what I’m reading it’s a 330hp engine? Or 310 I see multiple options.

 

[tpenfield]

I never understood what the LX signified . . .

The 7.4L engines 'shine' coming up on plane . . . probably better than the 454 MAG, since those engines are more suited for the top end of the RPM range.

 

[Roccafellas]

I never understood what the LX signified . . .

The 7.4L engines 'shine' coming up on plane . . . probably better than the 454 MAG, since those engines are more suited for the top end of the RPM range.

I spoke with Cobalt boats. Apparently it’s just a different intake manifold… and exhaust so they say. But this one is indeed a 7.4LX MPI Bravo 1. Thank you all for the help. If anyone else does have any info on an LX as opposed to regular 7.4L

 

[tpenfield]

It sounds like the only thing left to do is go get your boat.

 

[Roccafellas]

It sounds like the only thing left to do is go get your boat.

Thank you so much Sir. Will definitely post back Saturday once I get it.