Re:How Hot is Hot?

[jadney@vwtype3.org (Melissa & Jim)]

>From: David Yaghoubian <goob@dnai.com>

>(Stupid) Question:  Is my oil viscosity-less at this point (once it gets to
>over 300F) and if so does it regain
> viscosity again as it cools? Or is the oil "burned" after it gets this
>cookin and in need of changing?
>I regularly change oil every 1K or so, but am wondering if I should do a
>change after I get the engine cooking
>like this (which happens perhaps 3-4 times a year)?  THANKS!

All liquids change viscosity as the temp changes.  It is possible to plot a 
curve of viscosity vs. temp and the point of "multi-grade" oils is to try to 
flatten that curve, synthetics do an even better job of this.  Yes, the 
process is reversible.  Personally, I think that changing oil any more often 
than 3k is silly; I change every 5-6k, but I have a full flow filter.

Jim
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       Melissa Kepner                                    Jim Adney
       jadney@vwtype3.org              jadney@vwtype3.org
                             Laura Kepner-Adney
                             Madison, Wisconsin
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