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I am a beginner for Oil Analysis, I have got test results for fresh batch engine oil sample results and it is showing the water contents to be about 850ppm, I have one document I found from internet Table for oil analysis saying 800+ PPM water content is extremely dangerous, Another from MTU saying water content is allowed upto 0.3% (3000 ppm) and another document from CAT DEO saying it to be ok till 0.5% water.

So, what do you recommend, this is a emergency diesel engine genset which runs offload after 2 weeks for 15 min as a test run.


Similarly Table of Oil analysis is showing ISO 4406 to be 17/16/13 while the document from CAT says that ISO 4406 is not a criteria for engine analysis.

There is so much contradiction.....

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Its been years since being involved with a diesel but I did hold a Coast Guard license to be an engineer on diesel ships of unlimited horsepower. So, the question arises is your lab also doing a test for antifreeze and fuel in the oil? These are very meaningful tests when dealing with an internal combustion engine. It is one of the best ways to distinguish between a real issue, or simply the water being a byproduct of combustion as might be happening with your engine being run offload for 15 minutes every two weeks. Depending on physical size it might never be getting hot enough to minimize the formation of water in the oil.
RM
It is not about the diesel itself, its about the Engine Oil, 15W-40, Well I do agree that the engine isn't running sufficient to evaporate the water content but the question is different... How much water content is acceptable? below 100PPM, below 800 PPM below 3000 PPM aor below 5000PPM?

The ISO 4406 particle count plays any role in Engine Oil analysis or not? if yes how much value can be accepted? One standard is giving a value 17/16/13 while other one is saying its meaningless because of additives present in Engine Oil will increase this number of particles....

So which one is true which one is wrong which should be followed? What personnels are doing as a practice.... I sampled new barrel oil and found particle number about 23/19/17 and water content 850... should I accept this batch or reject it????
RM
RA,

Might I suggest you use the engine OEM guidelines. If you have a Caterpillar engine, this company has been in business for many years and "should" have a firm grasp on wear metals/water/contaminants/fuel etc.. that is acceptable in their engines.

Welcome to the world of lubrication!

If the ISO4406 is centered around DIESEL ENGINES, does the standard call out a certain size/engine rpm/fuel type, etc? What I am getting at...you can set whatever cleanliness code you want but getting the oil to that level is the challenge!! The cleaner the oil the longer the equipment should last. IF the OEM has a value of 20/18/16 let's say and the standard says 17/16/13, either is correct. The OEM has set a value but you have the option to go cleaner.
To get oil cleaner you stated the most obvious, your supplier has provided you with oil that is questionable. Keep in mind, oil changes lots of containers/trucks/tanks etc prior to getting into a drum or plastic jug etc. The oil supplier will have factory clean standards of the oil they produce. If in fact the oil you have was produced with an ISO count of 23/19/17 then you got what you asked for, but if their target was 20/18/16 then somewhere in the handling the oil was contaminated or how you collected the sample.
AGAIN, you can not reject oil if you don't know the factory standard values, then you compare your new oil to the standard. If they differ by some agreed upon value between you and the supplier then yes you could reject the oil.
IF you work with your supplier they can most likely provide you with your ISO values, but it won't be for free.
Hope this adds value
Dave
RM
i would not worry about the water content found, it is well below what OEM's see as the upper limit for diesel engines. you should realize that when the engine is running there will always be water coming into the oil as part of the blowby gases. when the oil is at sufficient temperature that water will evaporate again. given the specific duty of this engine, evaporation might not take place, so you might see a rise after some time. as long as it is not higher then what the OEM thinks acceptable all is fine though.

as far as a particle count according to ASTM 4406 is concerned: it is of very little use since it can only be analyzed with transparent oils. that is most times possible with fresh engine oil, but it will not be possible with engine oil that has been used in a diesel engine for some time - the oil gets way to dark because of the fact that the dispersant/detergent additives used will spread soot coming into the oil with the blowby gases out through the oil, rendering it non-transparent in no time.
RM
At my last job (power plant) we had some Emergency Diesel Generators and a diesel driven firewater pump. Our external oil lab performed a "crackle test" and reported the water content as < 0.10% or > 0.10% by volume. The Operating & Maintenance Instructions from either of the engine vendors (EMD and Cummins) did not have any water content acceptance values specified.

We did not do any particle counting either (optical counting will not work with dark engine oil). I recommend locating your engine vendor's Manuals to see what they recommend testing/trending in regards to oil parameters. Both vendors I mentioned had some pretty detailed and specific guidance.
RM
quote:
Originally posted by Rang:
What was the test method for moisture content? The result being below 1000 PPM would rule out FTIR which leaves KF or crackle test.


Most likely it was a "crackle test" since the detection limit is about 0.1%. That may be detected within a fully qualified lab in accordance with a known standard, or you can do it yourself by dipping a woodchip in the oil and then try to light the oil covered end of it. If it crackles there is moisture present: 0.1% or more.
RM

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