T&T: Running too cool

[capteric36]

 I thought the point of the thermostat in the 
fresh water cooling system on the engine was 
supposed to stay closed until the engine reached 
the proper operating temperature.
 Don't diesel engines have thermostats?
 If one wants to run at a low speed to save fuel 
it should be just fine. Just make sure your engine 
has the proper thermostat installed and it is 
working properly.

 The only thing I think is actually bad for 
engines is running for extended periods at idle. 
As long as the engine is run above about 1200 RPM 
there should be no excess wear.

 Or am I nuts here?

Eric Thompson
S/V Procrastinator
South San Francisco
capteric36 at sbcglobal.net