Replacement MERCRUISER 7.4 on MERCRUISER 350 MAG MPI

I have boat BAYLINER 2855, 1991, engine MERCRUISER 7.4, drive BRAVO-II (propeller 17,5x21).
Boat and drive BRAVO-II in an excellent condition, but the engine already very old and I have problems every week.
I want to change the engine on new MERCRUISER 350 MAG MPI - such engine on new BAYLINER 285.
In my city there are no experts capable to give the answer to my questions:
1. This engine - a correct choice or is necessary other engine?
My requirements after replacement of the engine - the maximal speed - 35-37MPH, normal speed - 30MPH (by a boat 4 or 5 person).
2. Use old drive BRAVO-II with this engine probably?
3. I shall have what problems at replacement of the engine?
4. How consumption of gasoline will change?
5. What RPM of the engine will be at speed 30MPH?
It is very grateful for any help!

Re: Replacement MERCRUISER 7.4 on MERCRUISER 350 MAG MPI

There is no way to answer your questions.

Re: Replacement MERCRUISER 7.4 on MERCRUISER 350 MAG MPI

Ayuh,... The 496 is the Direct replacement for the 7.4l...
Going to a smaller motor will result in Less power...
There shouldn't much of a problem with fitment, to the boat, nor to the drive,...
And,...As noted,..
The rpms,+ fuel consumption will be Unknown til it's done,+ Run...

Re: Replacement MERCRUISER 7.4 on MERCRUISER 350 MAG MPI

Why would not either rebuild your present engine or buy a reman long block. The 7.4L is a great engine with lots of toque. New fuel injected engines are very expensive when compared to reman engines and you could not pay back the extra expense in fuel savings.

Re: Replacement MERCRUISER 7.4 on MERCRUISER 350 MAG MPI

Plus your dumping a lot of money into a bayliner. If your boat runs you'd be much better off selling it and stepping up into a better hull with the motor you want

Re: Replacement MERCRUISER 7.4 on MERCRUISER 350 MAG MPI

Hey, hey, hey, JustJason, you are really putting out a bad opinion about Bayliners. I'll have you know that I own a Bayliner, I have first hand knowelege that you happen to be right. Ha!

Re: Replacement MERCRUISER 7.4 on MERCRUISER 350 MAG MPI

I just put lots of money into my bayliner. New 454 and still think it is a great boat.

Re: Replacement MERCRUISER 7.4 on MERCRUISER 350 MAG MPI

Plus your dumping a lot of money into a bayliner. If your boat runs you'd be much better off selling it and stepping up into a better hull with the motor you want

Click to expand...

Ayuh,... That ain't Bilgeliner Bashin',... That's just common Dollars,+ Sense....
Return on investment would be Much Better...

Re: Replacement MERCRUISER 7.4 on MERCRUISER 350 MAG MPI

For some I would imagine ROI isn't the important thing.