Opinions on filter magnets and oil analysis

[Johnnybgoode]

Any advice on whether using magnets on the oil filter negates the benefit of an oil analysis routine? I know the analysis will still show any non-ferrous materials and would be useful in that regard, but part of me says if I can get the majority of the ferrous stuff out of the oil it would

1) be better for the engine and still show the material when the filter is cut open

2) skew the oil analysis data

Experience with both? Opinions? Advice?

Thanks!

[Marauder]

Any advice on whether using magnets on the oil filter negates the benefit of an oil analysis routine? I know the analysis will still show any non-ferrous materials and would be useful in that regard, but part of me says if I can get the majority of the ferrous stuff out of the oil it would

1) be better for the engine and still show the material when the filter is cut open

2) skew the oil analysis data

Experience with both? Opinions? Advice?

Thanks!

Usage of rare earth magnets help collect small ferrous metal chips if they exist in the oil. They will not interfere with the oil analysis since the analysis is looking for elemental metal adsorbed in the oil.

I use the magnets on the filter and have the oil analyzed.

[chrisk]

Don't tempest filters have magnet included? It should make finding metal in the filter easier. I don't think it would make a difference in oil analysis, but you might call Blackstone labs.

[kortopates]

Don't tempest filters have magnet included? It should make finding metal in the filter easier. I don't think it would make a difference in oil analysis, but you might call Blackstone labs.

 

Indeed Tempest have been including magnets in their oil filters for awhile now. As Marauder explained, the magnet grabs chunks of metal that the oil analysis does not/can not see while the oil analysis is analyzing elemental metals that the magnet does not see. It really helps illustrates the point of why it is so important to open and examine your oil filter for metal with every oil change. 

[Vance Harral]

I've never really understood what the magnets are supposed to accomplish, can someone explain?  Are there particles small enough to pass through the filter media and re-enter the oil system, but large enough to be "caught" by the magnets?  Or do they just eliminate the extra step of sawing out the filter media and spreading it out to look for particles when you do cut the filter?

[orionflt]

Tempest does have a magnet incorporated in their base that will help to collect the metal particles in one area, that being said those particles would still be caught by the filter media. the big advantage to the magnet is that it will hold those particles in the filter if the filter goes into a bypass state. todays filters are set up with a bypass mechanism that is actuated anywhere around 12-15 psi of back pressure, this prevents you from starving your engine of oil if your filter becomes clogged. we can also see bypass operations at startup on cold days, this is where the magnet is the most critical. with out the magnet some of the particles previously trapped in the filter can make their way back into the engine thru the bypass operation. 

 

If your reading this and starting to worry you may be damaging your engine because you are not using a magnet, don't. when our engines were first designed and certified most of them used a screen filtration system that was extremely inefficient. infact that is what was installed on my engine when i bought my plane. because of their inefficiency you did oil changes at 25 hour or more depending on the operating conditions to keep the harmful particle count down and the efficiency of the oil up. todays oil blends and the better filter technology allows us to run the oil longer between changes.

 

Brian 

[Vance Harral]

Thanks Brian, I'd forgotten about the bypass mechanism.  Makes sense.

[carusoam]

Oil analysis will give an indication of rust forming on a cam...

Filter magnet will collect parts of the cam as it fails...

If your oil analysis and screen are clean, you fly more comfortably?

Best regards,

-a-

[Johnnybgoode]

This was kind of the line of my question - I haven't seen a detailed sample report and should probably ask Blackstone how much the report helps in identifying shaft problems that will not be manifest if a magnet is used. Just the engineer in me wondering...