Engine warmup/operating temp. WAS: aero blades more fragile?

[cobram at juno.com]

Components do not contract when they're heated, they expand.  How can
tolerances be tighter at  colder temps?  If this were the case, things
would start seizing up after they got up to temp.
An engine which is allowed to warm up at idle will last longer than one
that is driven off the line cold, it's negligible but measurable.  
Increased friction because of cold lubricant, degradation of the
lubricants by condensate and unburned fuel, less efficient heat transfer
in a cold cylinder from the air-fuel mixture to the cold cylinder walls
and pistons is what happens when an engine is warmed up, whether you let
it idle or drive it immediately, it makes NO DIFFERENCE in engine and
component wear characteristics.  
The real reason they want people to drive off the line with everything
cold is to save gas and reduce emissions.  Both admirable goals, and with
modern engine management and components there is no damage done doing so
AS LONG as you drive very conservatively until everything warms up. 
Suggestions from manufactures et. al have nothing to do with components
lasting longer or wearing less. 

BCNU,
Yahoo nuked my website with no warning.
"A government big enough to give you everything you want is a government
big enough to take from you everything you have.
 
Brett Dikeman <brett.dikeman at gmail.com> writes:
 
> Nope, idling when the engine is cold.  Tolerances, mostly cylinder
> wall-to-rings, which are designed to be 'right' at the proper 
> coolant
> temperature, and are much tighter when the engine is cold.  The 
> only
> thing it'll really effect long-term is compression, slightly.  
> Lower
> temperature thermostats (or stuck-open thermostats) cause the same
> problem.