"Bowgus" wrote in message
...
It's not "overheat" or "underheat" ... it's "uneven heat" that (I was
told)
may cause a problem ... it's ... one part of the engine is hot and one
part
of the engine is cold(er) than it should be because of the lack of
temperature regulation provided by the thermostat. I myself will run my
engines with the thermostat installed ... you guys can do (obviously) as
you
like :-)

OT: My mercruiser thermostat is 140 F ... I myself find that unususual
compared to an auto thermostat. My understanding ... an auto engine is
most
efficient around 235 F (achievable because the sytem is pressurized). So
...
why the low temp for the marine (version) engine?


Because if a raw water cooled boat engine is run in salt water, then the
salt will precipitate out and plug up the engine cooling passages at about
160 degrees. So they run a 140 as standard. My carbed 351W closed cooling
ran a 160 thermostat. Do not know what the new 350 mpi runs.