"Eisboch" wrote in message
...

"JimH" wrote in message
oups.com...


I did notice the temperature ran at 135 when at idle, at 140~145 at
cruise
and at 160~165 at WOT, then back down immediately to a lower
temperature
when at cruise or idle.

I plan to keep the 140 in the rest of the season.



Is that engine raw water cooled or does it have a heat exchanger and
closed loop cooling?

Eisboch


Raw (fresh) water cooled. The good news is that the temp never got above
165. The bad news is that it fluctuated to an extreme. I am concerned
about the way the temperature is bouncing around as I am used to seeing it
rise to a certain temp and stay there.

I will definitely be bringing the boat to a reputable mechanic at the end of
the season to take a close look at the engine, knowing a rebuild or
replacement may be the result. I don't, however, want to throw away the
rest of the season by doing that now if I can limp through this problem
without causing further damage to the engine or causing another overheat
situation.