[Vwdiesel] Dumb Question

[LBaird119 at aol.com]

> Diesel exhausts last much longer because there is less corrosion form the
> diesel exhaust.

  This is due to less sulfuric acid I believe is what I've heard.  I know
that's
a big difference in engine oil accumulations.  What seems odd is that we
always hear about the sulfur in diesel but it's the sulfur in gas that makes
compounds that mix with water to make H2SO4!

a. there is no throttle plate, so you get full flow, based on
> engine
>  speed, through the exhaust to purge moisture, I also believe there is less
>  moisture in diesel exhaust.

  Kind of.  The less moisture only comes from more dilution due to being
at "full throttle" all the time.  Burning a hydrocarbon makes CO2 and H2O.
With more energy in diesel than gas, there would be more water per gallon,
but with more air per stroke, there would be less water per cubic foot of
exhaust.  Of course the big "fan" blowing it away helps.  :)

You certainly don't see condensation on cold/
> damp
>  mornings like gas engines emit. Also, exhaust temps might be lower. Those
> are
>  the reasons you never had to work on the exhaust system. Also, the metal is
>  pretty thick on OEM pipes. Typically last 200,000 miles plus on VW diesels.
>
  With just the right conditions I've actually seen the vapor cloud come from
diesel exhaust.  It's rare though.  The reason they make the diesel exhaust
thicker is to keep it from shaking in half!  :)  Local muffler shop has made
the system out of roll bar tubing on a couple of occasions!  A couple of
problem Rabbits kept breaking the exhaust where it goes over the axle.
Mine's broken there two or three times in it's life.
  The exhaust temp is cooler due to the higher volume of air.  Kind of odd
when you think about it since the higher temp drives off the water in a
gasser.
Of course air volume with lower temps works as well or better.  :)
     Loren