apparent cleaning ability.
The way I do this is to carefully cut the filter elements out of the cans without damaging them. Some elements are open at both ends, and I seal these tight at the end that goes toward the dome of the canister--away from the threaded end. I have a bread loaf pan of 5W-20 motor oil that I have mixed in a copious quantity of talcum powder (about 10 microns average as per The Filter Council); about half a cupful per quart. The mixture is thoroughly stirred, and the filter elements to be compared are immediately lowered in at the same time. When the the center tubes of the elements are full of filtered oil, A syringe is fitted with a 12 inch piec of 1/8 inch inside diameter tubing which is used to stir the inner contents of the filter and then draw a sample. The sample tubes are filled and plugged with pieces of nails at both ends. These sample tubes will be mounted vertically for more than a week to view the amount of filtrate that stacks up on the bottoms for comaprison. However, a lot can be seen just by the initial clarity of the diffeent samples.
I also note which filter elements fill faster/flow better.
A mention about the filters' advertized efficiencies:
The PureOne model that I used--a PL20195 states 99.9% efficient at 20 microns. (20 one-thousandths of a millimeter)
The Mobil 1 Extended Performance M1-209 states 99.2% efficiency, but without giving a particle size for which it can earn this rating. However, by telephone to the maker, Champion Labs, they told me they were "in the ballpark of a 10 micron nominal" filter. This means they catch about half the 10 micron sized particles--and more as the debris gets bigger of course.
The Toyota OEM made by Denso, part number 90915-YZZD1 stated nothing specific.
The Fram PH3593A (orange can) is shown as 95% efficient >20 microns. Presumably, they think you don't know what > means.
The WIX built NAPA Gold 1348 has a nominal rating of 21 microns and a Beta of 2/20=21/37. The beta means 21 micron at 50% and 37 microns at 95% catch, respectively.
The K&N HP-1004 I used, according to K&N via email:
Filter media efficiency (per ISO 16889):
100% at 40 microns
100% at 35 microns
100% at 30 microns
99.4% at 25 microns
98.9% at 20 microns
97.1% at 15 microns
92.3% at 10 microns
82.5% at 5 microns
But I am skeptical of the test conditions as this element was tested twice and never gave as clear of filtrate as it should have by comparison with know filter types.
Here are some pictures:
Left to right: Fram orange, WIX, K&N
These have settled for a few days. I am non-plussed by the NAPA Gold/WIX. But This does correspond to the given betas, efficiencies, in my opinion. It is a well built filter, but has never been an outstanding performer in my cleaning tests. I used Fram for the low standard.
The Wix NG still did a bit better than the K&N.
Left to right: PureOne, Toyota OEM (Denso), Mobil 1 E.P., WIX, K&N
It is hard to tell from the photo, but there is a clear visual difference in the first three, and the second two. The order of cleanliness from best to worst is also left to right. The PureOne, as expected, was outstanding. The Denso and M1 were almost the same but I have to give the nod to the Denso. The Denso also flowed best of all. The WIX and K&N were a bit on the mediocre side of cleanliness but both flowed well.
The PureOne flows twice as fast as the same models made several years ago. There must have been some concern about strat-up valve rattle--but I am speculating on that. The flow charts I have seen for the PureOnes show a nice, pleasing flow curve comparing favorably to other popular filters. The M1 flows about 2/3 again as fast as the PureOne in my test.
Of course, these are all at room temperature with gravity pushing the oil in.
So there you have it. Numbers are numbers, ads are ads, and dirt is dirt when held up to the light.
Rob
