Can a magnet lower particle counts?

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Just curious if anyone has tested for particles in the 4 to 20 micron size for a given oil filter then run it again for the same oil/time with a magnet.
 
Just curious if anyone has tested for particles in the 4 to 20 micron size for a given oil filter then run it again for the same oil/time with a magnet.

It would be pretty much a waste of a test. The magnet could only affect iron particles and the filter media doesn't care the composition- only the size.
 
The answer is that it should reduce particle counts.
We have seen images of filters using magnets cut open and there are particles captured.
The question is if it is significant enough to register/matter.
 
The answer is that it should reduce particle counts.
We have seen images of filters using magnets cut open and there are particles captured.
The question is if it is significant enough to register/matter.

You need to change "should" to "can" ( at best) because the ultimate determination of what count is represented in a sample is where, when and what conditions the sample is taken from and the protocol. Then its a question of does the reduction matter.

Example- if there is a wear generating condition ( call it any given component giving off particles) putting a steady stream of particles in the lubricant stream and you sample upstream of the filter, no amount of anything is going to affect the count ( as you see it on the report)

Conversely, if the mechanical condition exists that's generating wear exists- pouring clean oil on it will have a net zero effect on reduction of wear. ( particles captured or not)

Listen to one who has been involved in tens of thousands of samples with magnets, voodoo and anything else a client can invent- machine wear from 'circulating particles" is very rare indeed. Statistically almost all wear comes either from a mechanical issue such as wear, geometry etc. or a lack of proper tribology ( for a million reasons).

I have seen people go to McMaster and even get 100 lb. magnets ( thinking more is better) and I have seen them on filters, on flow pipes ( even some made stubs out of brass or SS to "do even better" and could be removed for cleaning) and even seen them in sumps or directly under streams ( common in machining applications for coolants)

None of them significantly affect wear, vibration, thermal analysis or anything else because the 'circulating stuff" isn't the big problem.
 
Addition of magnetic filtration is used a lot in industry, and if there weren't any benefits it wouldn't exist.

As far as magnets added in the everyday passenger car engine oil filtration scheme, it probably doesn't help much, but ultimately any particles that are prevented from going round-and-round in the oiling system can't hurt. I've used magnetic drain plugs in all my vehicles for years, and use it mostly to monitor for any abnormal wear. It was interesting to see the level of collected debris fall off quite a bit as the engine broke-in. Once past 5,000 miles and a couple of oil changes, the level of collected debris pretty much stabilized. But if it all of a sudden increased with subsequent oil changes, then it would give some indication that something might be going on.


 
Addition of magnetic filtration is used a lot in industry, and if there weren't any benefits it wouldn't exist.

I never said it didn't exist or doesn't have benefits, now listen to one who actually has the real world experience in it and then I'll add the rest of what Bennett's article didn't cover.

It works very well as I said upstream it has its place particularly in hydraulics, machining and in many mining applications.

Here's the problem with other machines. Magnets with a gauss field high enough to capture such particles in motion and actually retain the ferrous particles also have the field strength to induce residual magnetism into other particles ( both smaller and those who get knocked loose) and guess what they do?

They circulate and have a tendency to attach to other surfaces such as ways, bearings and other things, accumulate and possibly break off in globs and exacerbate the very wear they were installed to stop. ( not to mention the proper filtration media should capture and retain them anyway)

The magnet is more of a "shiny object' casting an illusion to the untrained customer to make him believe he accomplished something rather than an actual realized benefit. Feel free to test that and put the magnet POST filter stream and lets see what it captures that the filter didn't.

So, in "general machine wear"- circulating particles are not a primary wear generator

Don't confuse advertising literature as a legitimate justification and don't base everything on 1 dimensional puff pieces written in articles without knowing all the details.
 
Feel free to test that and put the magnet POST filter stream and lets see what it captures that the filter didn't.

Pretty much everyone knows that the majority of the sub 10u ferrous particles aren't going to be caught in the average oil filter. So yes, magnets located even after the oil filter will catch ferrous particles. A very high efficiency oil filter (99+% @ 20u) will catch way more sub 10u particles compared to say a filter at 50% @ 20u. Will it help reduce engine wear? ... the answer is yes, but probably not to the degree that most people care about. And as mentioned earlier, the length of the OCI has a factor in all this, because X particles circulating through the oiling system for Y miles is a factor to the level of wear taking place. The longer the OCI, the more a cleaner level of oil becomes beneficial.

So, in "general machine wear"- circulating particles are not a primary wear generator

Nobody ever said it was causing "primary" engine wear. There are lots of articles out there saying it's the sub 20u particles that do the most "normal" level of wear. Bottom line is the less debris there is in the oil going round-and-round for X miles, the better. I'm still waiting for someone to show an SAE type study that says cleaner oil doesn't result in less engine wear. Wear due to parts shedding much larger wear particles due to inadequate lubrication, parts failure, etc (what I'd call an "abnormal wear level") isn't what magnet filtration is focused on.
 
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I dont know how much of a magnet you would need to pull metal out of a pressurized stream but I do know that the factory put magnets in the differential and transmission pan so I added a magnetic drain plug to the oil pan and I always find metal stuck to all of them when I change the fluids. Is it slowing wear, I dont know but it makes me feel better.
 
Just as a quickie experiment, I tried gently stirring just-drained warm oil for a minute or so with a magnet.
Result: It captured nothing visible. (Yes, I realize it might've missed a particle or two.)
 
Magnets only attract ferrous metals (ie: iron,steel and some nickel compounds) and the
bearings are not any of those. The ferrous metals would come from cylinder
walls and rings. Any cast off from camshafts and rocker arms would be very small
and likely not captured by a filter.

My 2¢
 
I have seen people go to McMaster and even get 100 lb. magnets ( thinking more is better) and I have seen them on filters, on flow pipes ( even some made stubs out of brass or SS to "do even better" and could be removed for cleaning) and even seen them in sumps or directly under streams ( common in machining applications for coolants)

I once saw someone stick several magnets from old SATA hard drives on the filter of their dirt track car, and none of them were on there after the race. Made of a rare earth metal, I figure the heat got to them and demagnetized them.
 
Pretty much everyone knows that the majority of the sub 10u ferrous particles aren't going to be caught in the average oil filter. So yes, magnets located even after the oil filter will catch ferrous particles.

No a logical fallacy founded in an appeal to authority based on a circular argument will never become a fact regardless of how it is spun and the frequency of it. Lets see one of your famous "links to a study' showing this is in fact true. When you fail to provide as you normally do, I'll come back and revisit this with actual facts but you first. The difference is I actually do this- not just read about it.

A very high efficiency oil filter (99+% @ 20u) will catch way more sub 10u particles compared to say a filter at 50% @ 20u.

Many seem to forget or simply don't comprehend that all these filter ratings (ISO) are QUALITY tests for COMPARISON of products and performance against a UNIFORM TEST ( exact round beads, constant flows, constant temps etc- none of this represents real world conditions). NONE OF THEM are representing actual performance in usage. You nor anyone else can say with any degree of accuracy that any filter will do 'this or that" in actual conditions. This is like comparing a stage performance to reality. Those who do the real world stuff understand this.

There are lots of articles out there saying it's the sub 20u particles that do the most "normal" level of wear.

Those articles are too broad to be of relative value because a "wear particle" ( to perform 2-3 body wear) has to be relative to the gap otherwise it cant get in and wear at all. Those articles are just vague generalizations with the barest minimum of factual data supporting them and even then in very confined scenarios. They don't apply "across the board".

I'm still waiting for someone to show an SAE type study that says cleaner oil doesn't result in less engine wear.

Red herring, non sequitur and at best only a tangent because the lubricant is only a PART of the wear process in terms of prevention, management of wear and overall tribology- so demanding a non issue as some validation of your incorrect premise and pontificating the fact its not there is right up there with saying that since you cant prove "X" that somehow defaults to "Y" being true. Another fallacy.

Wear due to parts shedding much larger wear particles due to inadequate lubrication, parts failure, etc (what I'd call an "abnormal wear level") isn't what magnet filtration is focused on

No, magnetic filtration is about capture and retention and I explained that in detail
 
Is it slowing wear, I dont know but it makes me feel better.

Respectfully, its not 'slowing' anything and they ( marketers) are counting on you "feeling' it.

People have been peddling placebos and panacea for centuries based on illusion, prestidigitation, anecdotal claims that never had a basis in fact but were 'accepted' just because. That's true far beyond magnets in oil.
 
I figure the heat got to them and demagnetized them.

If I were to guess, I doubt that because the heat required to demag is close to red hot or greater- there would be plenty of evidence of that temperature.

I would lean toward the field strength being inferior to the forces exerted on the magnet combined with surface contact area as the most likely candidates.
 
Any cast off from camshafts and rocker arms would be very small
and likely not captured by a filter.

Most likely, by weight/location and fluid velocity- the bulk of them simply sank to the bottom of the sump and never made it to the filter. ( which is what most do). Once there, they usually stay there.
 
I have said for ages that magnets have some obvious shortcomings when it comes to auto engines.

High temps cause them to lose their attraction for ferrous debris, and many of the particles are NOT iron. I have always worried if you have a magnet with a chunk of particles attached and you run the engine up hard, will they simply come loose and re-enter the oil flow?

Just like a bigger oil filter, it is a "feel good mod" with little proven benefit except to your worried mind!
 
I have said for ages that magnets have some obvious shortcomings when it comes to auto engines.

High temps cause them to lose their attraction for ferrous debris, and many of the particles are NOT iron. I have always worried if you have a magnet with a chunk of particles attached and you run the engine up hard, will they simply come loose and re-enter the oil flow?

Just like a bigger oil filter, it is a "feel good mod" with little proven benefit except to your worried mind!
Thought of that too … a Gold Plug drain bolt might make more sense being it does not see impingement
 
Just like a bigger oil filter, it is a "feel good mod" with little proven benefit except to your worried mind!

In fairness ( with all variables equal) a larger filter can and will extend change intervals ( do it on lots of equipment) so that's a benefit when calculated in terms of downtime, cost/frequency to change and so forth. Other than that tangible benefit, just increasing dimension does very little as you said.
 
I have always worried if you have a magnet with a chunk of particles attached and you run the engine up hard, will they simply come loose and re-enter the oil flow?

I mentioned that earlier- they can and sometimes will. You can distinguish them on the forensic exam as the ones clumped together and clinging and don't easily fall off when rinsed with cleaner. Then put them on a slide and run the gauss meter over them.

That being said, weaker magnets like the rubber stick ons do this more than truer rare earth types.

Its all relative to the mass and geometry of the particle, the field strength in gauss, fluid velocity and inertia as to how many(much) particles can be pulled out of a given stream and retained.- that's not a true linear equation.
 
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