Neodymium magnets on oil filters possible problems

[Stewie]

Originally Posted By: circuitsmith
I put a neodymium magnet on the bottom of my oil pan next to the drain plug.
I think it will catch more there because the flow velocity is lower than in the filter so particles aren't swept away.
I pull it off when I change oil so most of what's caught will go out the drain.


Didn't it melt?

 

[dailydriver]

Originally Posted By: 147_Grain
A magnet similar to the one below goes on the transmission drain pan of all my vehicles:

http://www.jegs.com/i/FilterMAG/384/TM360/10002/-1?parentProductId=813786


IF my T56 had ANY ferrous material at all on the outside of the case, I too would have one of those on it.

 

[ZeeOSix]

Originally Posted By: badtlc
Originally Posted By: ZeeOSix


The magnets can catch a lot of ferrous particles that the filter will not catch.


That picture doesn't really prove anything. Those are particles caught before the filter media, not after. Unless there was a way to know those particles had passed through the media and had not just reached the filter for the first time, you can't take much from it other than it shows there are particles in the oil that get to the filter.


I think the majority of that "black sludge" material the magnet catches is ferrous particles way smaller than 20 microns. Probably more like in the 3~5 micron range.

 

[Stewie]

Originally Posted By: ZeeOSix
Originally Posted By: badtlc
Originally Posted By: ZeeOSix


The magnets can catch a lot of ferrous particles that the filter will not catch.


That picture doesn't really prove anything. Those are particles caught before the filter media, not after. Unless there was a way to know those particles had passed through the media and had not just reached the filter for the first time, you can't take much from it other than it shows there are particles in the oil that get to the filter.


I think the majority of that "black sludge" material the magnet catches is ferrous particles way smaller than 20 microns. Probably more like in the 3~5 micron range.


IF they were smaller (3-5 micron) you wouldn't even be able to see it.

10 microns or 10 micrometers is the size of a blood cell.

Comparison here: http://learn.genetics.utah.edu/content/cells/scale/

 

[ZeeOSix]

Originally Posted By: Stewie
Originally Posted By: ZeeOSix
Originally Posted By: badtlc
Originally Posted By: ZeeOSix


The magnets can catch a lot of ferrous particles that the filter will not catch.


That picture doesn't really prove anything. Those are particles caught before the filter media, not after. Unless there was a way to know those particles had passed through the media and had not just reached the filter for the first time, you can't take much from it other than it shows there are particles in the oil that get to the filter.


I think the majority of that "black sludge" material the magnet catches is ferrous particles way smaller than 20 microns. Probably more like in the 3~5 micron range.


IF they were smaller (3-5 micron) you wouldn't even be able to see it.

10 microns or 10 micrometers is the size of a blood cell.

Comparison here: http://learn.genetics.utah.edu/content/cells/scale/


Yeah, but you see the total accumulation of it all by the magnet. If you could separate one lone particle from the "black goo", you probably couldn't see it with the naked eye.

 

[Pontual]

Sure, and that filter coil pic looks like Fe material to me. The neodimium shouldn't be (never) placed at the head (top) of the filter, but near the bottom (entrance/exit) side. And it doesn't melt, just loose force and fall to the floor at temperatures above 83 C. In my vehicles it hardly happens, and I never lost one single mag.

 

[badtlc]

Originally Posted By: ZeeOSix

I think the majority of that "black sludge" material the magnet catches is ferrous particles way smaller than 20 microns. Probably more like in the 3~5 micron range.


Like I said, that is your guess. You can in no way use that picture as supporting evidence.

I really like the idea of magnets for additional filtration but it might be worthless unless you are using a rock catcher for an oil filter.

 

[Pontual]

2 microns or 100 microns would pass throught the filter when in by pass, ASAP.

 

[Pontual]

But it catches MOS2 and colloidal graphite, also! Specially when at rest, no flow.

 

[ZeeOSix]

Originally Posted By: badtlc
Originally Posted By: ZeeOSix

I think the majority of that "black sludge" material the magnet catches is ferrous particles way smaller than 20 microns. Probably more like in the 3~5 micron range.


Like I said, that is your guess. You can in no way use that picture as supporting evidence.


If you want "evidence", then go find it yourself.

 

[UncleDave]

Originally Posted By: badtlc
Originally Posted By: ZeeOSix

I think the majority of that "black sludge" material the magnet catches is ferrous particles way smaller than 20 microns. Probably more like in the 3~5 micron range.


Like I said, that is your guess. You can in no way use that picture as supporting evidence.

I really like the idea of magnets for additional filtration but it might be worthless unless you are using a rock catcher for an oil filter.


Actually you can say for sure than anything trapped on the side of the can is a particle your filter doesn't have to catch even if it would- extending filter life.

If he took the filter mag off and put a strong drain plug magnet on the same paste would be on the plug magnet as the majority of it goes right through the filter.

Sure one 3 micron particle may be too small to see but millions of them all together are not.

Guys say all the time that the "paste" would be caught by the filter, but if that is true so why does it end up on a magnetic drain plug? The answer is self evident- because the filter does NOT catch it.

If the filter catches it there shouldn't be anything on the magnet - right? - but there always is.

When you clean off the either the plug, or cut the filter and run your finger over the millions of particles that are caught where the filter mag is - you can answer for yourself wether you'd want those particles between your crank and main bearings with the engine under a load or not.

Guys running stationary gensets costing more than automobiles, guys running exotic racing engines, guys running rental dozers and heavy equipment that need to run forever where one more season before a rebuild is the difference between profit and loss.

"But the factory would put them in if they were needed" - I hear this all the time too. Lots of manufacturers do use them in many industries.
My marine equipment (very high load) has magnets everywhere in the engine & in the drive (2 in the drive actually).

Lots of manufacturers skimp on things they should use all the time- I see vehicles rated to tow 5K+ without external oil or transmission coolers, trucks with too small brakes - auto manufacturers build to a profit line and lean on the aftermarket heavily to make up where they skimp.

Between 20 and a 100 bones for a reusable item you can keep your whole life- why not?

Alexi Sahagian builds 2400 HP compound super turbo engines and more.
Notice the angle Alexi uses is that it extends the life of you filter.

https://www.youtube.com/watch?v=IVvoeeIqUPU

 

[dnewton3]

I don't really have a dog in the hunt, because I believe filtration, while very important, is over-rated in terms of BITOG love affairs ...

However, UncleDave, I do have one thing to point out.
Your assertion that if the filter did catch those things, they would not end up in the pan. Problem with your logic is this; the oil flow path causes the contamination to touch the pan before entering the filter, with any (let's just use the generic word) debris. A magnet on the pan plug really is limited; here's why ...

Here is the cycle as we think of it cycling:
Oil is picked up by the pump from the pan
Oil sent to filter
Oil contaminated by engine
Oil returned to the pan

But here is the cycle in terms of contamination presence:
Oil contaminated by engine
Oil returned to the pan
Oil picked up by the pump from the pan (here is where the magnet would exist and have it's effect PRIOR to the filter)
Oil sent to filter


For the very first pass of a quart of lube, it would be true in your logic. But not after the first full cycle. In each subsequent cycle, the contamination is introduced by the engine, then goes to the pan, then the pump (with magnet), then filter. Hence, the debris you state should be caught by the filter is caught prior to the entry into the filter.

I completely, wholly agree the filter won't catch all; we all know that. And neither will the magnet. But they do more as a team than just the filter alone.

Each element (filter and magnet) has pros and cons:
- Filter sees ALL FLOW and therefore has a large chance to catch large particles, but is designed via pore size to ignore and pass small stuff. 100% flow exposure; limited size capture ratio. It cannot catch all sizes, but will be presented a large volume to sort through. Filter can also catch non-ferrous particulate; a unique trait contrasted to magnet.
- Magnet sees limited flow (only what passes close by it), but has the ability via it's field to capture any particle regardless of size. 100% capture ratio; limited flow exposure. It will capture anything ferrous within its field, but cannot catch what is not presented.


Magnets on the pan or at the tip of the drain plug do help, but because of distance they don't do a great job. On an engine or gearbox with no filter, a magnetic plug is probably a big help. On a pressure fed system with a filter, they pale to a filter. But magnets mounted on the filter kind of get both worlds; at least close. If you get a magnet that wraps around the filter canister, it can see a larger percentage of the total flow, and still have its wide ratio effect. Magnets need proximity to be effective. They lose their force effect with the square of the distance. Rare earth magnets help overcome this with the density of their field relative to their size.


However, as much as the theory and visual evidence is exciting, I have yet to see any real evidence that the items (magnets) actually effect the wear rates. The typical variance of daily wear far exceeds the effect I see from these items. Hence, I really like the idea, but see no real reason to run out any buy one. Show me a car that lasted some measurable distance further because it had a magnet on it for the whole life of the vehicle please. Most any car can EASILY go 300k miles if well cared for with just routine products and efforts. How much further would a magnet-equipped car go? I can't tell you, but the macro data suggests they don't really alter the true lifespan of the engine. Even if they did, their effect would only be realized past where a normal car would fail. Since most people experience an event that takes the vehicle out of service BEFORE it fails, it's just moot. People will sell, wreck, trade a car before it's really done for. Or other conditions (rust) condemn the vehicle before the engine quits.


Do magnets hurt the engine? No.
Do magnets help the engine? Probably so.
Do magnets effect the lifespan to a tangible degree that will make it worthy of effort and expense for the typical user? Data suggests not.


My two cents.

 

[Clevy]

Originally Posted By: UncleDave
Originally Posted By: badtlc
Originally Posted By: ZeeOSix

I think the majority of that "black sludge" material the magnet catches is ferrous particles way smaller than 20 microns. Probably more like in the 3~5 micron range.


Like I said, that is your guess. You can in no way use that picture as supporting evidence.

I really like the idea of magnets for additional filtration but it might be worthless unless you are using a rock catcher for an oil filter.


Actually you can say for sure than anything trapped on the side of the can is a particle your filter doesn't have to catch even if it would- extending filter life.

If he took the filter mag off and put a strong drain plug magnet on the same paste would be on the plug magnet as the majority of it goes right through the filter.

Sure one 3 micron particle may be too small to see but millions of them all together are not.

Guys say all the time that the "paste" would be caught by the filter, but if that is true so why does it end up on a magnetic drain plug? The answer is self evident- because the filter does NOT catch it.

If the filter catches it there shouldn't be anything on the magnet - right? - but there always is.

When you clean off the either the plug, or cut the filter and run your finger over the millions of particles that are caught where the filter mag is - you can answer for yourself wether you'd want those particles between your crank and main bearings with the engine under a load or not.

Guys running stationary gensets costing more than automobiles, guys running exotic racing engines, guys running rental dozers and heavy equipment that need to run forever where one more season before a rebuild is the difference between profit and loss.

"But the factory would put them in if they were needed" - I hear this all the time too. Lots of manufacturers do use them in many industries.
My marine equipment (very high load) has magnets everywhere in the engine & in the drive (2 in the drive actually).

Lots of manufacturers skimp on things they should use all the time- I see vehicles rated to tow 5K+ without external oil or transmission coolers, trucks with too small brakes - auto manufacturers build to a profit line and lean on the aftermarket heavily to make up where they skimp.

Between 20 and a 100 bones for a reusable item you can keep your whole life- why not?

Alexi Sahagian builds 2400 HP compound super turbo engines and more.
Notice the angle Alexi uses is that it extends the life of you filter.

https://www.youtube.com/watch?v=IVvoeeIqUPU




Just because there's slime on the magnet doesn't mean the filter is missing it. It's entirely likely that there's accumulated insols on the bottom of the pan and Its never actually being circulated thru the filter,so your assertion that just because your magnet is catching it doesn't mean the filter wouldn't.
And though I might agree with the idea in the real world spending money to try extend engine life when it's not the engine typically that condemns a vehicle to the recycler is tough for me to justify
Unless there's a problem that requires addressing what's the real point. Where's the line of redundancy?

I'm asking

 

[ZeeOSix]

Originally Posted By: dnewton3
Show me a car that lasted some measurable distance further because it had a magnet on it for the whole life of the vehicle please. Most any car can EASILY go 300k miles if well cared for with just routine products and efforts. How much further would a magnet-equipped car go? I can't tell you, but the macro data suggests they don't really alter the true lifespan of the engine. Even if they did, their effect would only be realized past where a normal car would fail. Since most people experience an event that takes the vehicle out of service BEFORE it fails, it's just moot. People will sell, wreck, trade a car before it's really done for. Or other conditions (rust) condemn the vehicle before the engine quits.


Dang, since it doesn't really matter what efficiency filter is used, or motor oil, or if a magnet is used or not doesn't help a car last longer ... then we all might as well use junky filters and change oil every 3K miles and shut down the oil and filters forum on BITOG.

Just kiddin' ... what would be all talk about then?

 

[stchman]

I'm sorry, but the whole magnets on oil filters is a complete load of manure. Someone created a gimmick and made some money.

 

[901Memphis]

My filter mag always catch tons of particles, some are large and some paste like

 

[ZeeOSix]

I run strong magnetic oil plugs. They certainly do catch the "black goo", but I also use them to monitor the health of the engine. If the black goo level increases, or larger ferrous particles start showing up, then I know something is going on that's not normal.

These photos are the magnetic drain plug used in my 2005 Tacoma, and was when the engine was new and breaking in. It has since shown a big reduction of collected debris as the miles have gone on.



Half of the debris is wiped off so you can see the level of collection.

 

[Bigdaddyeasy]

If the design of your filter permits you can buy high temp neodymium button magnets that are small enough to cover just the space between the holes on the face plate of the filter. A magnet is much better at catching metal through flowing oil if its actually in the path of flow. Needs to be high temp magnets though otherwise heat will damagnatize them.

 

[ExMachina]

I'd do a drain plug magnet, not an oil filter magnet, since you don't want oil flowing rapidly over the magnet surface. Oil naturally mixes in the oil pan, and the flow velocity is so low near the drain plug that particles can stay on the plug easier.

Rear diffs have drain plug magnets from the factory. Of course, I'd like there to be more magnet surface back there. Thinking about sticking one inside the diff's pool at the bottom, but concerned it might get caught in the gears!

 

[UncleDave]

Mr dnewton3 I have read your very informative posts for years as a guest and for a while now in membership form. I would like to say I have tremendously enjoyed the wealth of information you’ve shared. As a guy that contributes in a large number of forums I understand the time you’ve given us.

Bitog group make a lot of noise about auto oil filtration and for the most part I agree its much ado about nothing.

I agree a magnet in the pan is much more limited in effectiveness due to proximity than a filter type magnet than a units snaps onto the side of can, or even better a magnet on each side of the filter can.

I completely agree in the 2used together being a “team” approach to filtration, and if I could only have 1 I’d pick a filter for sure. No contest there.

Let talk about this a bit.

But here is the cycle in terms of contamination presence:
Oil contaminated by engine
Oil returned to the pan
Oil picked up by the pump from the pan (here is where the magnet would exist and have it's effect PRIOR to the filter)
Oil sent to filter

(I think we agree) There is no guarantee particles will be caught anywhere in one pass especially if the particles are below or at the filters threshold – but even with both a filtermag a napa gold, and a magnetic drain plug on a new rebuilt motor - we get fuzz in 2 places.

We can be fairly certain however that metal pieces just under the filters rated size (say a 19 micron magnetic debris flowing through a 20 micron filter) may never been caught by the filter, but stand a good chance of being caught sooner by a filter mag, or later with a drain plug either way particles under the filter rating definitely aren’t getting caught at all by the filter.

The paste and parts held in suspension at 19 or right at 20 microns may miss the filter or magnet who knows how many times - especially if the magnet’s a drain plug type.

Does potentially millions of particles just under the filters threshold flowing around with no way to catch it mean anything to an owner? Up to him or her to decide.

As for hard evidence that such grit of varying size affects the lifespan of a passenger vehicle dramatically there is little to no hard evidence to that fact. There haven’t really been many studies about it I could ever find but the manufacturers whose vehicles come with them arent claiming they greatly extend the life either, but they put them in.

For a relatively lightly loaded auto passenger vehicle, agreed one will likely throw away the car before the engine itself wears out - there may be little value beyond feel good.

Most auto engines are so lightly loaded the level of filtration in them matters very little if at all - this is why you can get 10K out the oil between changes there just isn’t much load on you average joes rig. Cars go hundreds of thousands of miles with little to no maintenance and tons of neglect – they just aren’t stressed a lot.

Trucks, boats, high performance small engines (motorcycles turbo sand rails) high load gensets and diesel motorhomes aren’t so lightly loaded and experience much higher wear.

When we say extend life- in high value engines that may mean extending an expensive components life so that it may be reused at rebuild time. Because with a marine engine rebuild time is coming way sooner than an auto or even and airplane engine. The ability to reuse and polish an expensive crank vs regrind, or rebuy at rebuild time would make the extra filtration worth it.

Cranks that are scratched so deep they cant be polished out are only scratched this way from larger pieces of debris in the oil. With good filters, magnets and regular maintenance I’ve never lost a crank at rebuild time due to deep scratches and because of lifetime of performance boating I’ve paid for and dealt with way more engine rebuilds than the average joe car guy.

I totally get the average 10 year car guy doesn’t care about the depth of scratches in the crank of a worn out engine – if he can even wear it out to begin with. I don’t care about my lexus crank when I’m done with the car- because its all going to the compactor.

My marine engines aren’t disposable like this though.

The guy who invests in a Sonny Bryant knife edged 4340 rem polished crank that can hold 1000 ponies cares tremendously about scratching the journals up. Under higher wear magnets trap significantly higher amounts of gunk than these few fines you see on the picts in the automotive threads.

The loads imposed on the mills are massively higher than auto applications as are the costs. The Ilmor 710 Marine V 10 is spec’d 0w40 Mobil 1 and a 25 hour change interval on an 8.5 quart sump vs an average car that can go a leisurely 10K on a 5 quart sump.

A standard marine big block chevy is good for about 250 hours on the top end and 450 hours total on the bottom before its totally leaks down so as to kill its performance and efficiency.

Most performance marine guys run non bypass Wix filters as the thicker oil and larger sumps means more time more time spent with bypass open in the marine world than the auto world. I had a relatively high hour big block chevy completely plug a wix non bypass filter after 35 hours of runtime with gunk - had I had magnets on this build it would have kept some of it out of the element. I surmise enough to get me till end of season oil and filter change, but it certainly would have made a difference that day. There was enough restriction to kill the oil pressure and go into alarm sending us back to the ramp for a pull out and a diagnosis.

Vehicles that share the same transmission oil with the crankcase like motorcycles benefit way more than autos as the oil gets mixed in with punishing gear to gear slams that chip away at the face and slowly bend the shaft, and magnets holding these pieces away from the rotating parts can only help.

So yes I agree there is little to no hard evidence that show “greatly” extended wear much like a cheap filter vs. expensive filter and dino vs. synthetic, but as with most things a team approach seems to work better and catch more than a single approach and for so little money In these apps I add them.

I end up as usual aligned with your knowledge and experience on a passenger auto side of thongs, but diverge with different applications based on experience.

Do magnets hurt the engine? No. - agreed

Do magnets help the engine? Probably so - agreed

Do magnets effect the lifespan to a tangible degree that will make it worthy of effort and expense for the typical user? I’ve really not seen any data either way but would not be surprised if it suggested no “greatly” extended life in an automotive app.

For higher load higher wear applications than passenger autos I believe they contribute to “the teams” effectiveness more than enough to warrant the relatively low cost of purchase.

Your money your engine your call, but magnets are the cheapest filter “bolstering/supplementary filtering” mechanism I can find to protect these high dollar mills.

My car- more a wear check gauge than than a lifesaver, but for 20 bucks its worth it to me if only to see as some guys have - a needle bearing stuck to it on removal.

I appreciate your input and candor thanks for the time to add to the discussion with logical fact based input and little to no emotion.

Its refreshing.