On Jan 25, 2010, at 6:11 PM, John Sessoms wrote: > From: mike wilson >> John Sessoms wrote: >> >>> > If you have a car that only gets used for short, short trips, it is a > >>> > good idea to get it out on the highway once in a while just to get it up >>> > > to a high enough operating temperature to boil the condensed water >>> > vapor > out of the oil >> If your oil (although some true synthetics may alter this premise) is up >> over 100degreesC you are in trouble. Even more, if you can get it anywhere >> up there, whilst it is being actively cooled by the engine design, you have >> travelled a long, long, long, loooong way. And even more, if you are >> seriously mayonnaised you are going to do irrepairable damage to the motor. >> Just change it. Less fuel, less danger, less wear and tear. > > I'm sure I worded it all wrong. Wouldn't be the first time. But I don't think > the engine oil actually has to get to the boiling point of water to evaporate > the moisture.
Motor oil can easily reach 100• C when driving at sustained high speed in warm weather. What's more oil on the upper cylinder walls can exceed 150• C. Water evaporates rapidly at these temperatures. A lack of high-speed driving will also lead to water accumulation in the exhaust system, shortening the life of the muffler and pipes. Of course the exhaust parts of newer cars are more corrosion resistant than those on older vehicles, but they're not high-grade stainless. They'll still corrode if exposed to constant moisture. Paul > > The idea intended was that an automobile needs to occasionally be taken out > and driven enough to get it up to and keep it up at proper operating > temperature for an extended time - more than a few minutes. > > The car will last longer if you do that than it will if you only use it for > short trips and never do really get it up to proper operating temperature. > > And it IS a good idea to change the oil once in a while. AND check the oil > once in a while between changes. > > I guess the thing is this. I've been seeing a lot about electric cars lately. > They seem to be good for about 45 miles per charge. > > If all of your driving is such that an electric car could do the job on one > or two charges a week, but you have a regular automobile - that regular > automobile will serve you better, last longer ... if you do take it out on > the highway for a couple of hours every couple of weeks. > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
