Mine would idle just perfectly but would shake at 3k.

Haven't solved the vibration issue yet, they're still messing with the carbs. Holley 800's and a dart intake, wouldn't have thought it would be such a temperamental setup, but apparently it is.

Did you get an answer to the flywheel. My friend is going from a 454 to a 502 and said he had to change the flywheel because it is externally balanced (or visa versa).

It shouldn't be tempermental. They should also be dialed in on the water. Can't really dial them in exactly without a load on engine and the boat sitting at the same angle as it does in the water.

Cuda, its a new flywheel installed.

Griff, last night they were running great while sitting on the lift but too dark to put it under a load. This morning it was a different animal, wasn't idling right and had to be feathered to start and warm at 1400-1600 RPM's.. There's no choke on the carbs, he has the choke plate strapped open.

Port motor cut out on me as I was coming up on plane, spitting back like crazy, then I couldn't get it started again. Saturday evening he was adjusting the timing and idle, but didn't rejet yet, says that's next step. I'm assuming all this "dialing in" takes time? I guess this is why factory packages still sell relatively well?

Update:

Took the drives off and reinspected both bearing installations. There was no problem with the alignment, so we're down to the flywheel issue I guess.

Engines were brand new Gen 6 long blocks from Fond du Lac Merc distributor. The flywheels were ordered from another vendor. I'm assuming they shipped and installed the right flywheels, but won't know for another few days, the performance shop is going to double check. In any case, it looks like the engines will have to be pulled.

PUT A DIFFERENT SET OF PROPS ON AND TRY THAT FIRST/Darin

Hi Darin, we did that a few weeks ago.

UPDATE: 5/21/03

Engines were lifted and inspected flywheels. Mechanic tells me today he installed new flywheels, made a comment to the effect the ones installed this winter said "Gen 1" on it, and the new ones installed this week said "Gen 2". I'm assuming they installed the wrong flywheels which caused the vibration, and that this will fix the problem. Hope to test next week.

Gee sounds familiar