UOA Particle Count & Oil Filter Performance

[Blue99]

I’m a little bit hazy about the connection between the particle count services, offered by Blackstone & Butler, versus oil filter performance.

Looking at the Blackstone site, ISO 18/15 is still considered clean oil, and the 18/15 rating allows 2500 total particles greater than 5 microns and 320 particles of 15 microns or greater.

So, what’s more important as a gauge of filter performance, the total particle count greater than 5 microns or the simply the count for the larger, greater than 15 micron size particles?

 

[Gary Allan]

Good question

Now surely you would expect fewer larger particles with better filtration ..but you should also expect lower smaller particle production.

There you did it...another variable that requires trending to be of much worth. Now you need to do your 6k OCI with the same oil ..with different filters.

FWIW and IIRC, even those with bypass (TP) filters have a fairly high count in the 5um range. This would make me lean toward looking for reductions in the larger particles for determining the effectiveness of filtration. It also kinda infers that even bypass filters don't cycle enough oil to maintain any sump "clean" in 6-9um particle levels.

 

[Blue99]

From ekpolk's UOA:

PARTICLE COUNTS

Size of Particle

>=2 microns 757
>=5 microns 280
>=10 microns 77
>=15microns 30
>=25microns 7
>=50microns 0
>=100microns 0

So, if the particle count indicates roughly 500 particles in the 2 to 5 micron range, more existed in the oil stream & the filter removed these very small particles?

Doesn't the amount of particles, in the 2-5 range, of the unfiltered oil stream, have to be known?

 

[Gary Allan]

Let me see if I can get your question straight here. Are you asking if you need a "before and after" comparison to glean any useful information? As in pre filter and post filter???

I don't think so. The appearance of oil from one cycle to the next is basically identical. Not all particles are trapped in each cycle. That is, a 15um ..or a 30 um particle may find its way through on one pass ...yet be trapped on another. So, unless you have an isolated (not in line) fitration system that is of a very fine um level ..one pass will pretty much look like another. I'm talking for a ff filter here.

You can also figure that since there are particles between 2um and 5um ..that even a bypass doesn't see enough oil to eliminate them. It's probably a "life average" type thing. You would probably get a good PC early in the TP's life cycle ..but less as it nears its end.

 

[Blue99]

Yes, before & after.

I don't understand how a filters' performance can be judged by viewing a single particle count tacked on to a single UOA.

The contaminant level or particle count for the engine is an unknown.

Without establishing a baseline, a good particle report could be due to either a clean running engine with an average filter or a dirty engine with a highly efficient filter.

 

[Gary Allan]

I don't think I agree ..but I understand your challenge to the procedure in determining how you stayed clean.

There is going to be particles of various sizes in your oil. The standards that achieve the "clean" rating aren't time weighted ..they're an independant standard. Hence if you get a "clean" rating over an OCI ..your filtration must be doing a good job.

The biggest factor to me is the "cut off" point for any significant particle count. If your filter is junk ..you can't get that low number ..no matter how clean your engine is over the OCI. That is, it may not be able to tell you if your filter is responsible for your clean rating ..but it surely can tell you if it's responsible for a dirty one. A good filter won't allow the dirty rating to occur.

Let's say (and I'm pulling this out of my behind here - so anyone ..feel free to correct me) I have NO greater than 15um particles ..but TONS of 2-5um particles. This would tell me that I have a dirty engine ..but a good filter. I slap on a bypass filter ..and my small particle count drops by 60% ....etc...etc..

 

[Blue99]

quote:

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Now you need to do your 6k OCI with the same oil ..with different filters.

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That's one of my questions, Gary, if several factors (engine deposits, PCV, efficiency of ring pack) influence the particle count of the oil, does lack of particles indicate a good filter or a clean, maintained engine running a quality oil?

If we look at the particle count for ekpolk's UOA from January 2005, is this a good filter or a clean engine?

GC 0w30 UOA with Particle Count

 

[Ugly3]

quote:

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Originally posted by Blue99:

quote:

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Now you need to do your 6k OCI with the same oil ..with different filters.

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That's one of my questions, Gary, if several factors (engine deposits, PCV, efficiency of ring pack) influence the particle count of the oil, does lack of particles indicate a good filter or a clean, maintained engine running a quality oil?

If we look at the particle count for ekpolk's UOA from January 2005, is this a good filter or a clean engine?

GC 0w30 UOA with Particle Count

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No question in my mind, an excellent filter produced those results.

 

[Filter guy]

Gary..I would tend to agree with you from what various lab people have told me over the years.

I'd also hasten to add..particle counts are better when you have multiple results to compare.

Then you get a more balanced view of what is going on with repect to the condition of your engine ( and oil).

Changing filter brands ( or types) with every oil change may not enhance ones results. If one uses a particular filter brand consistently....sees a "normal" level of particle counts over time ( say baseline)..then switches to a different filter, then one might ,imo, be able to compare one filter versus another as to how effective one or the other is. But chopping and changing all the time won't get you there.

Blue99 is that what your trying to figure out? One filter versus anothers impact on analysis?....

 

[Ugly3]

Filter Guy - Here is what he is trying to figure out.

So, what’s more important as a gauge of filter performance, the total particle count greater than 5 microns or the simply the count for the larger, greater than 15 micron size particles?

 

[Filter guy]

Then the answer is from what i've been told over the years.....

Engine manufacturers "say" that engine wear is created by particles from 5-25 microns in size.

Because of where the oil flows and the tolerances involved, it is not one size particle which is the key.

To use an analogy..if the bearing tolerances are, as an example, 16 micron...a 5 micron particle will be like a bowling ball between the gutters. A 20 micron particle won't "fit". One would need to be most efficient at 16 micron to protect the bearings.

Where people get hung up in their shorts is thinking that ..well why don't engine manufacturers just have a 5 micron beta 200 filter 99.9% efficient filter and be done with it.

Dirt holding capacity is the reason ( and filter by-pass valves). In order to do that ...with the same size filter you use today, then you might ( depending on how "clean" your particular enigne is) need to change your filter once a week. Cost effective?

Or the other option is to design by-pass filtration..and have you looked at the engine bays..where there is little room and incur higher pricing for the car to begin with ( they won't be free), and expect to teach millions about by-pass and it's benefits. plus take more time for an oil change. Not to mention higher costs. And more inventory space as every automotive company would design "their own" version which would me quick lubes would have 20-30 different types of by-pass systems and replacement elements to work on or clean.

Or..the filter you have on the vehicle now would need to grow to 3-4-5 times it's size, and cost, in order to last 3,000 miles. And we all know people are religious about changing at 3,000 miles...

So more safety factor would need to be engineered in which would mean an even bigger filter.

And at the end of the day the less than $20 oil change becomes a $50 oil change ( $100 or more for those top end cars) ...something consumers would really want from the first automotive engine brand that says "we have a better idea"...

They would but... their car sales would plummet once word got out...

So the compromize is to do as effective a job as possible at all micron particle sizes as an OEM filter. Then let consumers make an "educated" choice for a better filter in the aftermarket.

Which is where we are today.

 

[Gary Allan]

The cost/benefit isn't there either, Mel. Even with the 'less than ideal' situation, an otherwise well meaintained engine outlasts the rest of the car

quote:

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Filter Guy - Here is what he is trying to figure out.

So, what’s more important as a gauge of filter performance, the total particle count greater than 5 microns or the simply the count for the larger, greater than 15 micron size particles?

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I would think that it would be hard to say. Now surely if you have a low 15um and greater number ..then the filtration must be doing a good job. There are no contemporary common filters that work well in the 5um range for aboslutes. Even bypass filtration leaves plenty of 5-10um particles (although less then without it).

IMO, you can't assign a value (or discount) to any filter (regular spin-on of any quality) due to smaller size particle count ...or I wouldn't think.

Let me restate this so that I'm understood. One would reason that there are large particles and small particles produced. We can also figure that at least some of the smaller particles are produced by the larger particles that the filter does not trap. IF we have a distinct absense of larger particles ...we should be able to reasonably assert that the small particle number is not a result of larger particle insult in being allowed to bang around in the engine ...otherwise they would be apparent in the numbers.

We should then be able to say that if there is a higher small particle count ..but a favorable large particle count ..that the filter is NOT contributing to it in terms of allowing larger particles to knock new smaller particles off of resident bodies. We can then (again reasonably) assert that the smaller particles are produced independantly and not "resultant" of poor filtration and are probably soot from combustion byproduct and whatnot.

That all being qualified (from me, being an unqualified observer and just reasoning this out) I think you will tend to see, on average, a relationship where when you have a lower large particle count ..that you will have a lower small particle count.

...but you should NOT have a significant large particle count and a reasonable small particle count.

 

[Big O Dave]

I just sent in my first ever UOA sample to Blackstore/Dyson, and I emailed them to see if I could add a particle count, and if so, for how much.

They said I could, and it runs an additional $19.00US.

Just a FYI.

 

[Blue99]

quote:

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Blue99 is that what your trying to figure out?

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Yes, multiple UOA's to establish a particle count baseline, for a particular engine, makes more sense to me.

Once a distribution for particle size is established, than the performance of various filters can be gauged.

I also like Gary's comments regarding the lack of 15-25 micron sized particles as a measure of filter performance.

If ekpolk's particle count showed 2000-3000 counts in the 2 um size, indicating more small contaminants, and the 25 um size remained at 7, I think it would be safe to assume that the filter's performance is excellent.