Really Hot 164

["C.M. Smith" <cmsmith@domain.elided>]

 This topic keeps popping up. The 164 is a really hot car and loves it.
Relaaaax...and drive faster.

1.  if the car does not boil over it wasn't too hot, you just thought it was

2. modern engines are designed to run hot, really hot. Pressurized 50/50
glycol water boils at about 250 degrees Fahrenheit.  Engines don't start to
melt until much higher temperatures than that.

3. temperature sensors and the gauges they are attached to are notoriously
inaccurate. Get used to the indicated temperature your engine likes to run
at and assess the rate of change, not the highest  reading to estimate both
actual engine temperature and general health of the cooling system. Eg, my
SAAB 9000T runs at "normal" halfway between c and h on the gauge. Drive
hard with the boost positive and the temperature climbs to three quarters
on the gauge and stays there. On a really hot day the temperature needle
will move up to 7/8 and stay there. If the needle is stable and the
overheat light is off then your engine is not too hot, you just think it
is. My normally aspirated ALFA is much more consistent, running hot in
winter, really hot in summer, and really, really hot stuck in traffic....it
hasn't come close to boil over...and I've never had a modern car boil
over..ever. Well except my 81 GTV6 which knifed through its accessory drive
belt at 190 km/hr, talk about instant boil over! Guess I should've stayed
in 5th after all.

4. unmodified engines do not benefit from under-temperature thermostats.
These will eventually contribute to premature cylinder wall wear. You will
be wasting fuel running your engine too cool. Highly modified engines and
racing applications may require these thermos because the cooling system is
not adequate to deal with the additional heat rejection, this is a flaw in
the design, or a deliberate weight or money saver. after all, at racing
outputs and speeds the engine is going to be hot enough and the thermo will
be wide open anyway.

5. did i mention that cooling systems are a low maintenance system, not a
no maintenance system. If you flush the system every 24 months and install
fresh coolant or a good restorative conditioner, check your water pump belt
and keep the radiator clean, and replace the thermostat with a factory
specified new one at the first sign of erratic behaviour, you'll know the
cooling system is ok and the engine won't boil over.

6.  in modern cars don't bother slowing down to try and keep the engine
cool, don't use higher revs than normal (the electric fan don't know the
difference), do switch off the AC, and don't switch a hot engine off if you
have to stop to let it cool off unless it's boiling anyway. Switching off a
very hot engine is just going to provoke an instant boil over (self
fulfilling prophesy for cooling systems.... ohmigod she's going to boil
over let's stop and switch off, sure enough steam blows out as soon as the
car is stopped and the engine switched off. guess we should've stopped
sooner...nope..should've driven faster and kept that radiator cool!)

Let the flames begin...I'm cooler than you because I like my hot engines. 
Michael Smith
Calgary, Alberta
Canada
91 Alfa 164L, White, original owner 

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