Newbie to board w/engine questions

[Whiskey River]

I just recently joined the Maxum owners, have been a Glastron owner for several years but due to growing family finally bit the bullet and purchased a larger boat with cabin.
Previous owner was not too boat savvy and didn’t winterize last year so after about 100 hours of labor and several thousand dollars later the family and I spent our first weekend on the boat this past weekend (and LOVED it).
I was a mechanic for 18 years therefore elected to do the engine swap myself rather than pay a marine two arms and three legs to do the job for me.
Boat now has a remanufactured 7.4MPI long block with all new exhaust, tune up, water pump etc. etc. etc.
I write my first post to introduce myself and to ask if anyone else has the 7.4 MPI and any experience with running rich at idle, boat has a slight hesitation when just staring off around 1000-2000 RPM’s then will take off and run like a bat out of H_ LL. The running rich at idle and hesitation are the only two signs of this problem (knocking on wood).
Also here are a few pictures please give your reviews.

Thanks,
WR

[Ticamo]

Engine is distracted by bikini? :P

Sorry, no ideas from me. But anyone whose first post involves bikini pics is OK in my book. I am sure someone will jump in with something helpful.

BTW, I bet that thing does run like a bat out of h-ll w/ a 7.4 MPI.

[seapuppy]

welcome to the zoo WW...first off....that air cleaner isn't regulation..you need a flame arrestor rather than an air cleaner by coast guard regs......second...if it's hesitating at first opening...then the air is leaning out at initial opening and then the mpi is richening out ....that tells me either your o2 sensor is bad or that your mapping is messed up....get someone with a merc computer to attach to the boat and do some diagnostics......that will tell you exactly what is wrong...

finally....7.4mpi engine in that small of a boat will rip that bikini right off her!!....niiiiiiicee!!!!!

what drive are you running cuz the a1g2 drives aren't rated for that big an engine..!!!

SP :hello:

[Whiskey River]

Seapuppy, I am running the Bravo 3 w/dual 24p stainless props.

And yes occasionaly the wind will blow that bikini right off .

Thanks for the tip on the aircleaner, I thought it looked good at first but have since replaced with original as you stated it is NOT CG approved and had hoped it may be contributing to the running rich (but no such luck).

I am looking for anyone who may have a used scan tool for sale as I know this will be a much needed tool in the future and all my fellow boaters and mechanics in my area do not have a mercruiser or similar scan tool.

[Gazjen]

I don't know much about the MPI systems but can you check if the cold start system is switching off is the coolant sensor working correctly etc I've had this problem on a few injection cars before

[Whiskey River]

Just an FYI for the board..I found a very small fuel leak between the water seperator and fuel rial on the line feeding the fuel injection from the filter assy... Corrected leak and ran for about 5 minutes at about 1/2 throttle then back to idle.... Now runs like a sewing machine... Not sure if the leak was also causing it to pull air into line thus the reason it was leaning out at take off and loading up at idle... But (knock on wood) she runs like a champ from idle to WOT and back every time now with out any hesitation....

Just thought I would pass this info along to the board for referrence.

WR

[tglee]

Thanks for the update.