The problem is the lean setting of the idle mixture. The boat had to be CARB
compliant so Merc set the idle mixture as lean as it will go. When you take
it to the dealer they will say that it is nature of the beast, BUT you can
fix the problem after your waranty expires. On the side of the carb you will
see a tamper proof plug/circle, under that plug is the idle mixture screw.
Fatten up the mixture and the idle should smooth out just read this and it
will explain it all

http://p076.ezboard.com/fbocwebfrm33...icID=313.topic
good luck
by the way I have the same engine in a '05 175 Bayliner
Steve
wrote in message
oups.com...
I have a new 2007 Bayliner 185, with a Merc 3.0L 4Cyl engine, and an
Alpha 1 outdrive.

My issue (my dealer's issue to be more accurate) is this:

At idle, warm or cold, the engine vibrates horrendously, to the point
where it resonates (shudders) throughout the entire boat, shaking the
gunwales. The idle is currently at about 600 RPM. I have also
noticed that when I took the boat out of the water, the transom has
some black film on it. At speed, basically anything above 1100 RPM,
the engine performs perfectly. The boat has about 3 hours on it at
this point. It is going back to the dealer tomorrow for this issue,
but I was wondering if anyone else had run into a similar problem?

Other than this, I have been pretty happy with the boat. It planes up
in seconds, delivers the promised 42 MPH (on GPS) and is very stable,
even on the choppy early spring waters of Lake Erie.

Thanks,

Randy.

.