6.2 Mercruiser blown up 4th tiime!!!!! Help
02-05-2014, 10:56 PM
#51
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Not only can the EFI be tuned, but it has 10 times more tune-ability than a carb. Why do you think that no OEM, marine or automotive, builds a carb engine anymore. 99.9% of the engines we build are EFI. We can make a 1300+ hp engine idle at 700 rpm. We can certainly make a slightly hopped up 454 Mag idle with any cam you can stuff in it. Sounds like your "mechanic" either doesn't know how or doesn't want to mess with the EFI. I can absolutely assure you that the EFI on that Mag engine can be tuned to do whatever you want. The injectors are large enough to support about 650 hp. Honestly, the only additional money you would have to spend is to tune it, and that needs to be done with either induction system.
I'm just trying to make sure that you understand what you are doing. Personally, I think you are making a HuGE mistake by removing the EFI. Don't do what your "mechanic" wants you to do. Do what you want to do or what you think is best. Let me know if i can help in any way or answer any questions for you.
Eddie
I'm just trying to make sure that you understand what you are doing. Personally, I think you are making a HuGE mistake by removing the EFI. Don't do what your "mechanic" wants you to do. Do what you want to do or what you think is best. Let me know if i can help in any way or answer any questions for you.
Eddie
02-05-2014, 11:12 PM
#52
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I f your boat is a 242 islander, then I assume it has a built in fiberglass platform. If so they are prone to packing water into exhaust on launch off trailer or slowing down too fast.They MUST HAVE INTERNAL AND EXTERNAL FLAPPERS. If you have external, lift them up and look up exhaust. You might see where some rubber flappers were but burned out. Either way make sure and have both internal and external in good working order. I blew a 496 in no time due to this. Different boat but same style and it had a built in swim platform .
Chris
Chris
02-05-2014, 11:40 PM
#53
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Eddie I love when you actually post. So informative and on the money. It's the "mechanic" that's hit this guy thinking that way. Most of us know both are able to be tuned but even with a carb if you don't know how to tune it it won't run for **** either.
02-06-2014, 02:19 AM
#54
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Just spoke to my mechanic. I asked him do we know how reversion occurred. He said the 6.2 is notorious for this something to do with the cam design, he also inspected my exhaust and it's angles is to shallow flappers internally were not closing either. These all being addressed by new elbows and new flappers when new engine goes in
He also said go carburated because idle can be adjusted more easily to be increased bs the increased idle help prevent reversion/ efi won't adapt to cam he going with. He said to build the efi version with 475-490hp exceeds my budget for new injectors tuning etc, so carb is the best option
What is he doing besides a cam change to the stock engine??? A cam change does not equal 100hp.
You already have the complete EFI system. It just needs to be tuned by somebody that knows what they are doing. You should not need new injectors
02-06-2014, 07:38 AM
#55
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Just spoke to my mechanic. I asked him do we know how reversion occurred. He said the 6.2 is notorious for this something to do with the cam design, he also inspected my exhaust and it's angles is to shallow flappers internally were not closing either. These all being addressed by new elbows and new flappers when new engine goes in
Given the fact that your boat is a family truckster and not a performance boat, I would stick with a "family friendly" motor. My choice would have been a take-out 496 MAG or MAG HO as these motors would have been factory options. The 454 MAG MPI is a solid motor but it would not have been an option in 2004 as it was out of production. This may or may not come into play upon resale.
02-06-2014, 08:50 PM
#56
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I'm a carb guy myself and refuse to own a efi boat engine. In this case I would have stuck with the efi. If u can't fix the boat yourself and someone has to replace the motor then u prob won't be tuning the motor anyway. A simple plug in and tune can be done with efi (I think). Not just anyone can tune a carb. My carb 355 starts like any efi motor and i can work on it if I change something. I can't work on efi. I think u mite regret going to the carb!!
02-07-2014, 07:57 AM
#57
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I have a Baja H2X that is 24 foot and change. I am running a 496 HP rated at 375 HP with a bravo drive and 23 mirage prop. I love the EFI. All the big blocks around here that have carbs and many times run ethinol fuel have to deal with vapor lock issues.
My boat is turn key. the dream-o-meter flirts with 70MPH but GPS says 65. I am thinking of labbing my prop and get a bit more as I can hit the rev limiter alarm when it is cool out.
Me thinks 70 MPH while not impossible is pushing things and you will come up a bit short.
Get a mechanic that knows what he is doing OK?
My boat is turn key. the dream-o-meter flirts with 70MPH but GPS says 65. I am thinking of labbing my prop and get a bit more as I can hit the rev limiter alarm when it is cool out.
Me thinks 70 MPH while not impossible is pushing things and you will come up a bit short.
Get a mechanic that knows what he is doing OK?
