Mercury has all their engines set up to run rich from what I have seen. That is what keeps them alive. Lean one out and your asking for trouble.

You can have your ECM reprogramed if you want to change that.

Fix the engine hatch.

Replace rear bearings in superchargers.

Replace leaking seal on port supercharger.

Replace carrier bearing in extension box,
gimbal bearing and upper gear set in port drive.

The only "fun" thing I'd like to do is put a set
of 2" shorter drives on it.

No, I think you have to be rich to run them in this day and age!

Or you can be like me and not even own a boat according to "A Salt Weapon".

Now I have to figure out where all that money has been going!

What do you recommend?

jonyb, If you removed the stock Corsa mufflers and replaced them with straight tips, this will automatically lean it out to a very small degree. I have even heard of some people picking up a 100 or so rpm's from releasing the back pressure so I am sure this change will not make it run any richer than stock.

Thanks!! I'm already hittin the rev limiter, and there's a beep under the dash. Late in the summer I swapped the stock 3-blade to a Mach 24P 4 blade. That made a world of difference. It's running right at 5K rpm at WOT.

I definitely want to dump the mufflers though. Last year I had to rebuild the 454 in my H2X. It looked like it ran too lean, so I don't want to take that chance with this boat. Thanks for the replies.

Customtouch is exactly right. But in my experience you will not need to be concerned with lean or rich conditions if you are just changing the tips. Like he said that is a VERY small difference.

One thing however is if you are hitting the rev limiter the ECM is probably dumping more fuel into your engine. When you are running and hitting the rev limiter do you notice more black build up on the swim platform, and maybe a decrease in performance?

If so you are doing the right thing my changing props, but you may want to have the rev limiter increased. One guy I recommend for this is Tyler Crockett, there are several others that can do it also.

Good luck & Happy boating

Dock

Dock: The soot on the transom is terrible, and that's from day one. I read another thread here that was pretty old about that problem. He said they warrantied something (maybe the ecu) to fix it. Am I missing something?

I'll look into the reprogram for sure. Tyler Crockett: Is that his username? I can't find the 'search for member's' link like you can on other boards. Any idea of a cost? Other shops? I don't expect a lot of gains with just tips, but I want to make sure and do it right, to not screw anything up. With that prop, the boat GPS'd at 64.9. Don't know the water temp, but it was about 80 degrees outside. Thanks for the help, by the way...

jonyb, If you are out of warranty I would say have at it, with reprogramming or any other mods you decide to do. However if you are not, any mods to the computer or most anything else will void whatever warranty you have left! You probably already knew that but I just wanted to mention it in case you didn't.