Date:         Thu, 31 Dec 1998 19:37:19 -0600
Reply-To:     Blue Eyes <lvlearn@MCI2000.COM>
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Blue Eyes <lvlearn@MCI2000.COM>
Organization: Vexation Computer
Subject:      Re: Warm up time
Content-type: text/plain; charset=us-ascii

I've read the many people's thoughts about this exact topic,
warming cold engines.  Generally, the weight of opinion of
those whose opinions I trust most on other issues disagree
with Ken's on one point.  And that is not about excessive
motor speed when it's cold.  There seems to be universal
agreement among almost everyone on that except some nitwit
(just my opinion) who lived next to me with a new Mercedes
diesel who would fire that thing up in the dead of winter
and race its motor until it sounded like it was ready to
"lunch on the launch pad."   I identified with that motor
and I felt like I was being punished by this unfair action.
Ok, so I'm not rational.  <G>

Here's my understanding of the most preferred cold weather
starting method for long motor life.  As soon as you get the
motor to start, watch for full oil pressure to show.  That's
usually no more than 2 seconds.  Then, keeping the rpms as
low as possible to pull the load, put it in gear and start
driving very slowly, shifting up at as low an rpm as the
motor can easily handle the load of each next gear.  This
load warms the engine much more quickly and greatly reduces
the period during which motor heat is so low that internal
condensation of acidic combustion blow-by occurs, which
contaminates the oil.  The engine should be well heated for
long enough to drive any of this condensation into a
vaporous state so it can be purged from the system before
turning the motor off again.  So the absolutely WORST
driving cycle I've seen was the person on a 5 acre estate
who started her car and drove to the front of their lot to
get mail, and then drove back to park it until she repeated
the cycle the next day.  I got all kinds of flack for trying
to explain this.

Ok, supposing you have an automatic, and you'd prefer to not
run the motor fast enough in low gear to get it up to the
first automatic shift rpm.  Fair enough.  The same loading
to speed warming rules apply.  Start it.  Wait for the oil
pressure to stabilize.  Then with you foot on the brake, put
the transmission in "drive" and load up the engine to a
moderate throttle setting against the slipping torque
converter for a minute or two.  Then drive off.  You aren't
slipping any clutches.  They are fully engaged.  But you are
converting a lot of energy to heat in the transmission's
torque converter and warming the engine much more quickly.
It would take several minutes of slipping before the
transmission would get hot enough to cause trouble.  But in
the short term, you are greatly abbreviating your combined
motor and transmission's warming period toward normal design
operating temperatures.  While this procedure is safe and
based on good thinking, if you do it with an uninformed
person in the car, you're likely to experience another kind
of heat ~ social heat.  Just explain that you care so much
about their comfort that you're doing this to give them some
warmth from the heater faster.  That is unless you're a
glutton for punishment, in which case you can tell them the
truth.

Where's my asbestos suit?
John