Oil Analysis ?

I have been hearing people talk about getting thier oil analysed and I am just wondering where/how this is done?

I would definately consider sending a small oil sample off for analysis for a few bucks. Since I run Mobil 1 15W-50 this would be every 10K miles for a fresh change and 5K after that for analysis. I would change the oil filter every 5K though to get rid of any nasty particulates.

BTW Pelican has a good article on the sythetic oil and addatives in the tech forum.

Basically, where/who and how much $?

Thanks!

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Adrian Pillow
1979 911 SC
1966 VW Microbus
PCA - Peachstate Region

George Murphy handles this for the Mercedes group; you can find him on the Veterans Merc list.

Here is the skivvy (from an archive search of merc digest):

"In addition to monitoring your present car, the use of engine oil analysis can be of great value in checking out a used car which you propose to buy. Taking a sample of the oil after the engine has been well warmed up could reveal many things about the present condition of the engine, assuming the oil has been in the engine for 3000 miles or more.

Price: 1 kit - $14.95; 3 kits - $39.95 PLUS $3 shipping

You may order more than one kit at a time and save money - the price includes shipping and handling. The procedure for sampling is clearly described in the kit and should be followed meticulously, but it is not difficult.

George Murphy 423-482-9175 9 am to 5 pm ET Voice or FAX

Performance Analysis Co. 1345 Oak Ridge Turnpike, Suite 258 Oak Ridge, TN 37830

One thing about doing an oil analysis is that it can provide you with information on what particulate matter is in the oil, but unless it's comprehensive it doesn't help.

We do oil analysis on chillers and the price is about the same. You take an oil sample and send it in and about two to three weeks later you get a printout on what they found.

Unless you have been doing this on a regular basis, it is really not going to tell you much other than you have metal wear in the engine.

Different metals represent different components in the engine and the sample can help in distinguishing these metals. You then need to know where they are coming from.

If they can tell you that, than it's worth doing. Again, in order to keep up with whats going on in your engine you have to do it on a regular basis. On chillers we do it twice a year. On cars, I'm not sure.

Steve

A one-time oil analysis won't tell you much of anything unless the engine being sampled is in such terrible shape that the oil is full of bearing metal or cylinder-wall scrapings or whatever. (I've had oil analysis done for years on my airplanes.) What you need to do is establish a baseline, through three or so oil-analysis samples, and then what the continuing analysis tells you is dangerous--or simply unusual--deviation from that baseline. Bottom line, you need to do oil analysis consistently, regularly and relatively frequently for it to be of any use at all.

Stephan Wilkinson

I would agree with Stephan 100%. A few years ago, I was flying along at 24,000 feet ( as pilot ) of a turbine powered airplane. Noticed ITT ( turbine temp ) had risen 20 degrees or so, followed by an increased fuel flow, then a slow but perceptable decrease in oil pressure. All of this occurred in 30-45 seconds. Sensing something was about to happen that would not be good, I proceeded to perform an engine shutdown.

Once on the ground, had the oil filter pulled. It was absolutely packed with metal shavings. Come to find out, the number 3 bearing in the turbine section had failed.

However, this engine had less than 10 hours on it since that last oil analysis, and that analysis found no indication of any metal particles whatsoever. Maybe in some cases it has value, but it provided no pre warning in this case.

What made this even more irritating was the fact the powerplant itself had barely 200 hours run time since its last major overhaul !

I had oil analysis done on diesel marine engines in pleasure boats I've owned over many years.
The oil sample you submit to the lab is typically vaporized by an electric arc, and the results are recorded by a spectrograph to be examined after the test. For the test to be useful you need to establish a baseline, starting from a low-hour (new) motor, and then, continue it testing on a regular schedule. As the hours (and years) roll by, you gradually accumulate a data base of metallic (and other) compounds as they wear inside the motor. Unless you are a metallurgist as well as the designer of the motor, you may have trouble interpreting the test results. The trained techs at the lab do that for you.
Oil anaylsis "saved" a 3208 Cat diesel for me by detecting a *very* small crack in the block. The anti-freeze coolant which was poisoning the motor oil was detected before it destroyed the main bearings etc.
As far as using oil analysis in automobile motors is concerned, I've never heard of anyone doing it. Big diesels in stationary and transportation applications, piston-powered gasoline aircraft motors, but no cars.

Regards,
Doug
'81 SC

Very interesting, thanks for the feedback.

So there is no way to tell if the oil has broken down and lost its useful life?

I thought the oil analysis was geared toward monitoring the life of the oil, more than debris in the oil.

How are people able to tell that conventional oil breakdowns in roughly 5,000 miles and synthetic can last 20,000 miles?

Maybe I am asking the wrong question?

Thanks!

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Adrian Pillow
1979 911 SC
1966 VW Microbus
PCA - Peachstate Region