Oiloil Filter Magnets

[pg4323]

I looked and wasn't able to find a discussion of the dozens of OIL FILTER MAGNET companies. Main ones I found:

1) FilterMag
2) Bear Trap by ONE EYE Ind. in Canada
3) FilterPLUS
4) MagnaGuard
5) FilterDot
6) magnetized oil drain plugs available just about anywhere.

Everything I read agrees that ferrous particulates, even those that are too small to be trapped in the best oil filters, are a major contribution to engine wear over the life of an engine.

Anyone have positive or negative experience with adding magnets to augment cleaning of motor oil.

 

[Dominic]

Well I have one on my Subaru which measured 2ppm of Fe in the oil after 5000 miles of use. Whether its the engine, the oil, the filter, or the magnet I got good wear. I will say this, the FilterMag has never fallen off and appears strong and sturdy, whether it helps or not I would have to do some UOAs to find out.

I bought a FilterMag because I know the oil filter can only filter down to maybe 15um sized particles, and I figured perhaps the FilterMag might get the rest out of the oil. All in all it appears to have not harmed my oil analysis in any way.

 

[Steve S]

can't hurt at all but the engine will last a long long time with out the extra $$$ spent on stuff .

 

[chevrofreak]

The only negative that I see is that it will screw with the wear metals in a UOA.

I have a couple insanely powerful magnets from an old hard drive on my filter right now. They're so strong I literally could not slide them apart, I had to pry them apart.

 

[pg4323]

I believe the kind of magnets used in computer hard drives, speaker magnets, etc are rare-earth (neodymium-iron-boron) magnets. These and other types of magnets are used by some mfrs.

If I understand it correctly, some magnets lose much of their magnetic properties when subjected to high temperatures. Most oil filter magnet companies use magnets less sensitive to heat and other factors that negatively affect the magnet.

Some use very strong magnets either on the dome end of the filter or attach them to the outside of the cannister. Some use polished ceramic magnet(s) positioned inside of the central (efferent) channel of the filter.

I'm probably a little obsessive but I wonder if using an external magnet and another inside the filter cannister to REALLY cut down the levels of suspended ferrous particles, the main filter misses.

 

[Gannet167]

I have a rare-earth magnet that originally was designed to fit on the oil filter, but the rubber strap holding it on broke. I used to just stick it on the filter but someone mentioned that the oil swishing around in the filter is moving very fast and is turbulent.

We thought it might be better to put it on the drain plug since the oil at the lowest point in the engine is likely not moving as fast and not as likely to wash away any filings. Also, any metal suspended in the oil will naturally settle to the bottom of the pan after the engine is shut off - and find it's way to the magnet. I need pliers to get it off the drain plug when I change the oil.

 

[severach]

I like my magnets in the oil where the strength is not attenuated with a metal shield and the magnets don't weather.

Automatic transmissions place magnets in the pan and some engine manufacturers supply OEM oil plugs with magnets so it definitely is a good place to put them. Heavy equipment manufactures tend to integrate oil magnets into the engine design. Someone thinks that magnets are a good idea.

The lower the cost the more magnets I can use so I buy neodymium magnets in bulk. No reason to pay $30 for a magnetic drain plug when I can make the same thing for less than $1. I epoxy a low cost round neodymium magnet to the drain plug and place a few more round magnets in the inlet of the oil filter. If the base and filter do not have enough room for the magnets and would crush them or restrict flow you might need to purchase a filter that has a more recessed inlet or smaller magnets. The filter magnets can be inspected and removed without destroying the filter.

You will always see iron filings too small for the filter on the magnets. Look for a trending down of wear particles to verify that they work either by UOAs or by watching the particle accumulation reduce over time.

 

[mechtech2]

It's gotta be better with magnets .
But th reality is only in theory and splitting hairs.
If the magnet does a LOT of good, the engine is in serious trouble.

 

[chevrofreak]

Originally Posted By: mechtech2
If the magnet does a LOT of good, the engine is in serious trouble.


Yeah, but the magnet could also prolong engine life by lessening bearing damage.

 

[pg4323]

Am not sure what you mean: "If the magnet does a LOT of good, the engine is in serious trouble."

 

[mechtech2]

Seeing a bit of collected powdered metal on the magnet would be normal.
But I don't think it really helps.
By a 'LOT of good', I mean if it is loaded [really 'doing it's job'] , you have serious engine trouble that is not normal.

 

[synman]

I would think if one is worried about fine paticles in the motor one could use a magnet but run a bypass filter as well.

 

[milwaukee]

It it possible the magnets could interfere with the by-pass valve operation?

 

[JAG]

I use MagnaGuard, FilterMag, and a magnetic drain plug. They all pick up ferrous debris.

Neither of the first two interfere with the by-pass valve from what I can tell. MagnaGuard does cover up some holes in the perforated core but not enough to concern me.

Some words of caution: some magnet materials erode if exposed to oil inside engines. I bought a magnetic drain plug one time that had that problem. A different issue is that the MagnaGuard magnets do lose magnetic strength over several tens of thousands of miles. I do re-use them but throw them away after that time period.

 

[severach]

That's why they are to be placed in the filter inlet only. No matter how they get damaged the filter will catch as catch can.

 

[chevrofreak]

I cringed when I saw a pic of what that MagnaGuard is. I have no interest in putting a magnet on the outlet side of the filter. Some filters with a nylon core probably wouldn't even be able to hold that magnet in place and it could go right into the engine.

 

[JAG]

On filters with steel cores, the MagnaGuard adheres to the wall strongly. I can barely pull it out with a needle-nose pliers. I've been using them for about 90,000 miles.