Stainless Steel Filters

[Baldy112]

I was just wondering what's everyones opinion are in regards to using stainless steel filters on gas engines.

More specifically this one :

http://www.scottsperformance.com/products.php?PartType=3

Are they superior to paper filters as they claim?

 

[kenvlach]

They claim "Our stainless filter catches items down to 35 microns."

A 35 micron particle is huge -- most humans can see down to ~1 micron. Premium filters are often tested at 5, 10 or 15 microns. For really fine filtration, down to 0.1 micron, add a by-pass filter. The Scott filters main advantage is that it's SS, so I presume you can clean with solvent or gasoline and reuse ~forever. As much work as replacing a conventional type.

There are better filters (w.r.t. fine particles) available, just Google.

http://www.google.com/search?source...GLG,GGLG:2006-41,GGLG:en&q=oil+filters+micron

"AMSOIL Spin on oil filter filters out dirt to about 5 microns. If you use the AMSOIL By-Pass system, it will filter out dirt down to 1/10 of a micron."

 

[BrianPetersen]

I know of the filter you're showing.

My true opinion of this filter would probably get the lawyers of the firm that manufactures it after me, so I will leave the following exercise to the reader.

Understand that a normal filter filters X percentage of particles of a given size on each pass (i.e. there is a small amount that gets through). Suppose X is 99% for particles of some suitable size (see above post). First time the oil goes through the filter, 99% of those particles are gone. Second time, 99.99%, third time 99.9999% and it follows that in VERY short order (seconds of engine operation MAYbe a couple minutes tops) the number of particles of that size range in the oil are vanishingly small.

Now ... Go out to your kitchen. Find a sieve. (That is a much bigger version of how that pictured filter operates.) Find some marbles. (Those marbles are the particles bigger than, say, 35 microns that they say is the mesh size.) Dump them in. The sieve filters out 100% of them.

OK ... Now get some sugar, slightly smaller particles than the mesh side, and dump that into the sieve. Better have something underneath, because the filtration efficiency is darn close to nil.

The information on that filter would suggest that the mesh size is in the 35 micron range (0.035 mm = 0.0014 inch).

Now ... Dig up the specifications for your favorite engine, and figure out what the clearance is between the crankshaft and the crank journals, and then tell me if you want that filter in your engine.

 

[evelrod]

Interesting. I should expect these type filters to be very usefull for filtering the oil where heat exchangers/pumps etc. are used to cool/lube differentials in race cars or heavy equiptment. It might even be great as a 'pre filter' on the engine. Should I desire more or "better" filtration than my Wix 51515R filters give me (<1 psi pressure drop at 5 to 20 microns), I think I would go to the old 'tried and true' "Oberg" screen filter. In actual practice, it is not at all commonplace to find automotive filters 'over the counter' at much 'better' than 35 microns.
Specialty filters, or rather, special application filters are readily available in the 5 to 10 micron range...just cost a bit more and are,sorry, not at "Wal*Mart".
Of course, if your into 'fuel magnets', PTFE additives, and such, you can always opt for the old "Gulfcoast" 'toilet paper' filter. I'll bet they are still around. J.C. Whitney, maybe?

But...What the heck, why pay any attention to me?...They sure are pretty! I'll bet they even come with a 'sticker'!

Rod

 

[patprimmer]

They very carefully word their statements to create impressions rather than real comparison. Their comments on paper filter does not say paper OEM quality oil filter. They could be comparing to the dust bag on a Hoover.

They say used in some very serious race events. Serious race engines are built in an environment approaching operating theatre standard and the oil is changed very regularly. In fact the engines are often rebuilt in less miles than an OEM oil change interval. Serious race engine builders use screen filters like this, or Oberg, or system 1, not to filter the oil, but to collect particles for inspection to indicate part failures. I think other brands offer a range of screen sizes.

If I ran a screen filter over 10 microns, I would also run a good paper filter in series after the screen.

Some statements like the one about fanning the clutch and debris in the oil in my opinion warrant investigation for fraud and should be reported to the local authority.



Regards

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