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MINI's!!!
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Yes, I'm a MINI maniac.

Well, at least the BMW-MINI.  A lot of people call this the "fake" Mini, but I've seen enough older ones to be REALLY happy with the quality my new one.  Here it is, named "Luigi" by my wife seconds after she first saw it on the dealer's lot last year.

luigi2.jpg

My MINI Blog

Since this is my website, I'm going to use it as I see fit. During the past year that I've owned this car, I've been pretty active in the bigger MINI bulletin boards, mainly North American Motoring and MINI Owners' Lounge.  Every now and then I read things that are simply wrong.  So rather than wasting everyone's time by by writing thesis papers in venues that should only have content no bigger than a TWITter post, I figured I should vent here instead.  At least here you expect me to be saying whatever I want, and you can always navigate away from this page if you don't like it.
 
So here goes:

06/10/2009 Oil Analysis to determine oil quality

One thing I've seen is people insist on using their own brand of oil and justify it by using oil analysis.  This gives them a reading of the metals and other substances present in the oil.  Based on these amounts, they draw conclusions about the effectiveness of the oil they were using.
 
That's an inaccurate use of the data, and here's why:
 
SpectroGraphic Oil Analysis Program (SOAP for short, the most common test) takes a sample of your engine's oil and burns in under controlled conditions.  They record the spectrum of the light (the color of the flame, for those of you who slept through physics class) and those colors tell them which metals and other substances are present in the oil and in what amounts.  Then a report is made of what metals were found and in what quantities.
 
Note that the oil is burnt to get the test results.  There's nothing in a SOAP test that measures viscosity, lubrication (friction reduction) quality, amount of additives left: no test is done to determine the quality of the oil.  It only tests for foreign materials. 
 
While this may seem to indicate the quality of the oil, the next question is what amounts of metal is normal?  No two engine wear alike, due to how hard they're used, in what sort of envirionment they operated in, etc.  And if you forget and change the oil for a month, the amount of metal in the oil is going to go up simply because there's been more wear.  So there's no fixed number that indicates excessive wear. 
 
Since every engine is unique, every engine has to set it's own "normal numbers" and is where the normal procedures for SOAP tests come in.  These are to change the oil as regularly as possible, usually after 100 hours of operation time for airplanes.  A sample of each oil change is sent to the SOAP testers.  They send back the results that you record.  Over many oil changes, an average amount of metal can be determined.  If, at a later date, a metal content spikes up, then you know that something made of that metal is wearing more quickly than before and might be getting ready to break.  It's then up to the mechanic to determine which part that might be, which then suggests how much work it might be to fix it.  In short, SOAP tests are a analytic tool used to judge the health of an engine.  Note that without a meaningful average, there's no way to tell what's normal and what's not.
 
Notice that in none of these tests do the quality of the oil come into play.  That is a completely different set of tests done by the oil companies.  Just because you're analyzing the oil, doesn't mean you're getting results about the oil's quality.  In this case, you're measuring the engine for wear indirectly by measuring the amounts of metal in the oil, not the oil for it's quality.
 
In short, you can't justify second-guessing the manufacturer about proper oil simply by using SOAP tests.  SOAP data isn't valid for oil quality and, therefore, decisions about oil quality based on that data are meaningless.
 
HA! See why I can't post this on a bulletin board?  Thanks for reading. See you next time.

And now for something completely different!