Marc Shaw

I just got the report for my first oil analysis done at 62700 miles a few weeks ago after a recent oil change with Mobil 1 15W50.

There are 370 miles on this sample of oil.

I have already submitted a second sample after about 2000 miles and will send a third just before the oil is changed (at 5000 miles).

Any comments? I've not read one of these before but it looks okay to me.

Marc

Heirsh

How many miles on the sample?

Bearclaw

I like Blackstone personally, because they give you a baseline comparison against normals for your engine type. I haven't done one on my Porsche yet, but I've done many on other engines and just off the top of my head, I'd say it looks good. Lead, alum. and copper are low, which I believe would come from bearing wear, and iron is low too. Nothing jumps out at you. I don't see 'fuel dilution' - giveaway of a leaky injector.

Looks like your oil properties are holding up fine - moly, phosphorous, etc.

Marc Shaw

About 370 miles.

Marc

Heirsh

Yeah it could look good, but from his post I get the idea thats fresh oil, i.e. no miles. If that is true then where did the iron, copper, and Al come from? The remaining 2-3 quarts of oil from the change mixed in? The 2500 mi will tell us more.

Unless I am misinterpreting.

Bearclaw

Yeahhhh, I see that now - 370 miles on the sample? Not really a UOA.

Heirsh

Marc,

My numbers on 2500 mi of Castrol 10w-60 and 5000 mi of M1 5w-40 are:

Aluminum 4 4
Chromium 4 6
Iron 11 19
Copper 5 9
Lead 1 6

I'll leave the rest off.

I have a potential problem with my chrome, but it dropped to a reasonable value with the 10w-60. The rest of my numbers are all quite good. If you like I can post my excel sheet tomorrow from work that has my numbers and Blackstones averages. I scaled them all to the same mileage for comparison. I dont understand why some of your numbers are high on 250mi. I think the 2500 mi sample will tell more.

Jeremy Pinsly

Marc,

Since this is apparantly the first time you have done this type of test for your car, consider this as your baseline measurement. As you put more miles on the car with the same oil in the system, you will obviously be able to tell if the oil is picking up anything out of the engine.

Did you submit for testing a control, i.e. unused oil directly from the Mobil container?

As far as what is "normal", I have no idea. I would be most concerned about seeing large differences from one sample to the next. This could mean the oil is doing its job in pulling debris out of the engine, inconsistent lab capabilities, or engine problems.

Not sure if this helps you or not, but the analysis itself is interesting.

DonW-Cape Cod

If you haven't contacted Larry you should email him at l0turner@comcast.net He's a knowledgable guy. Tell him I asked you to contact him.
Don

Marc Shaw

No, but they asked what type of oil was used so I assumed they had baseline values for each type of oil.

Okay -- sorry if I should know but, who is he?

Marc

9-kevin-11

Look at your oil analysis report... his name is in the upper left corner... I think Don is suggesting that you talk to him directly - and ask what he thinks of your report (whether its good, or too early to say much).

Marc Shaw

<--- me

'nuff said.

Marc

cwrm4

I have used oil analysis with aircraft and have only found it useful when you look at a series of results over a significant period of run time (like 100s of hours on an airplane or tens of thousands of miles on a car). You really need to baseline YOUR engine when it is "known good" as well. It is very easy to get worked up over nothing when you first are looking at an initial analysis of oil on a "worn" engine.

However, when a metal value is stable for a long time, and then it spikes...that's when you should get worried!

Marc Shaw

Okay so I contact Larry as Don suggested and he replied very quickly.

His reply follows:

"Hi Marc,
Tell Don I said hi! The way the analysis works is like this - it's important the oil is in the engine long enough to pick up contaminants and suspend them in the oil - then the analysis will detect them. It finds extremely small amounts - down to parts per millions - i.e. - a reading of 25 of, say, copper equates to 25 parts of copper in a million parts of other material.
BTW, I'm not trying to be condescending - but I never know the level of knowledge my customers have about this stuff - please forgive if it seems I'm explaining in simple terms -

Anyway - with a sample having only 370 miles on it, it might be considered "too soon" as we like to get 1000 miles on a sample before testing it so the contaminants are suspended in the oil - which is another reason for extracting the sample when the oil is warm. But it will give an indication. The levels you are seeing on your report are extremely low - they will never get to zero. To see what others are getting, take a look at "Test Results" in http://members.rennlist.com/oil (which is always shown in my signature lines) - you'll see the Copper levels get into the l40+ range before it become "Abnormal". By looking at the levels on the Test Results you can get a good idea of what the level will be before it becomes shown as "Abnormal". I have been asked about getting a list of contaminants with the thresholds of when a contaminant becomes "Abnormal". The lab will not furnish this because each brand of oil is different - as is each weight, engine, environmental conditions, operating conditions, etc making the this information difficult to pinpoint for all oils without providing a huge & complex database.

With 62k + miles on your 911 and the level of contaminants present, I doubt there's any problems in your engine. But it'll be interesting to see what the sample with 1000+ miles on it looks like - but I suspect it will be fine. Engines with problems - like damaged bearings or pistons, for example, tend to shed copper, aluminum, etc. at a rate that will show heavy levels of contamination in short periods of usage. But a sample with 1500 to 2000 miles on it gives a better long range forcast of problem areas.

Are you having specific problems you are trying to diagnose, or are you interested in Oil Analysis for its Predictive ability?

If I have not answered your concerns satisfactorily, or if you have additional questions or comments please do not hesitate to email me. I'm happy to help."

I did tell him about the thread here on RL and got his permission to post his reply:

"Not a problem - feel free to share any info I provide - you might also suggest they view the Test Results at http://members.rennlist.com/oil "

Thanks all.

Marc

jeff522

Thanks agin Marc for shinning the light of knollage in to the dark corners of my ignorance-Thomas Blaylock.