wrote in message
...
Dave Stadt wrote:
: How come the engine in my car with 190,000 miles is running fine with no
: signs of undue wear with nary a single preheat. It is often started at
: temps well below 0 F. Aluminium block, steel crank, steel cylinder
liners
: and aluminium pistons same as the ole Continental.

Two words: Liquid cooling. Everything about the aircraft engine is
catered to
running at ridiculously high temperatures during normal operation. The
oil is very thick
so it still lubricates at high temperatures and carries heat away from the
cylinders.

I use 15W50 in the Continental and 10W40 in the car. Not much difference.
Also, in the winter people run their Cont/Lycs on straight 30 weight. 30
weight is like water when at operating temps. I don't believe my O-200 runs
nearly as hot as a modern auto engine.

The
cylinders themselves have choke (they're slightly smaller bore at the
top), with the
thought being they'll expand to be straight when they heat up during
normal operation.
Those two things are the primary reasons.... lack of oil and scuffing of
cylinders.

Doesn't play. The pistons are aluminium and the bores are steel. In cold
weather the aluminium pistons shrink more than the steel cylinders and
clearance actually increases. The rings are steel and follow the cylinders.


-Cory

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