Not the belt. I had the belt on my 1950CL changed after six years because I
thought I was pressing my luck. I looked at the old belt before I threw it
away - it looked almost the same as the new one the dealer just installed;
no wear was evident.
Not the prop. Even if you smack something hard enough to damage the prop,
you'll still be able to limp back to shore.
I suspect a well maintained boat would leave you stranded only after
catastrophic failure - like a broken valve. Actually that happened to me
when my boat was brand new and I didn't know what was wrong. I limped back
to the launch ramp at idle speed. (MerCruiser replaced the engine.)
Oh: you know what'll do it? A failed fuse! I don't know why the fuse would
fail, but it happened to me. We'd been out for several hours, had just
finished about 15 minutes of idle speed operation, and when in idle the
engine quit and wouldn't restart.
I had an electrician aboard. His trouble shooting couldn't find anything, we
suspected the safety switch controlled by the lanyard. I forgot that among
the few fusses behind the instrument panel was one for ignition. That was
expensive. Cost me $130 for 2 hours of mechanic time before he checked for
that fuse.
The moral of the story is that a well maintained 3 liter mercruiser won't
leave you stranded as a result of anything you could foresee.



wrote in message ...
What might be the first thing to break or shut down on the little 3.0
Mercruiser engine that would leave you stranded in the middle of a
lake? Considering it's kept well maintained and run in the 3200-3500
rpm range. Excluding fuel and battery.
Thanks,
HJJ