On Sun, 31 Dec 2017 20:52:15 -0500, Alex wrote:

wrote:
On Sat, 30 Dec 2017 20:53:36 -0500, Alex wrote:

True North wrote:
On Saturday, 30 December 2017 11:33:19 UTC-4, Mr. Luddite wrote:
On 12/30/2017 10:10 AM, justan wrote:
I like being warm.
Short trips in cold weather used to be hard on a vehicles exhaust system. Not sure with the better quality stainless materials used today. I'd stay home and make my own coffee
The exhaust system? Where did you read that?
Yup that is true. If you looked at the old cars, you would see water
dripping out of the tail pipe until it warmed up. If you never got it
hot enough to boil out all the water it would start rusting from the
inside out.

Wouldn't condensation form even after a long trip when the car is turned
off in cold temps?

Yes, and here is the reason why:

A gasoline (petrol) molecule is made up as such:

C8H18 (or 8 Carbon atoms and 18 Hydrogen atoms)

Energy is obtained from the combustion of it by the conversion of a hydrocarbon to carbon dioxide
and water. The combustion of octane follows this reaction:

2 C8H18 + 25 O2 - 16 CO2 + 18 H2O

Or better said, you have two of the hydrocarbon atoms along with 25 oxygen atoms, they swirl
together into a mix, the spark plug ignites them, boom, and out the tail pipe comes 16 carbon
dioxide molecules and 18 water molecules ... at least in a perfect world. Some cars don't put out
exactly that ratio. There may be a little bit of carbon monoxide (CO), unburnt hydrocarbons (C8H18),
and/or nitrogen oxide (NO2) coming out of the engine exhaust port along with the CO2 and H2O. In
this case, the catalytic convertor's job is to help clean these up so you can get closer to the
perfect ratio described above.

As described, the water coming out of the tail pipe is a natural occurrence of the combustion
process. You will usually see it coming out of the tail pipe when the engine and exhaust system of
the vehicle is not completely warmed up. When it does become completely warmed up, you won't see it
any more, because it comes out as steam (well, you'll see it in the winter time if it's cold enough,
but you get the idea).

Furthermore, if you believe I wrote the above from the top of my head, you must think I'm Harry.