So I bought this oil filter at West Marine last time I was there getting some Starcool (propylene glycol coolant). Wasn't really any more expensive than your typical PH2 style filter, and I was intrigued by the box saying 10 microns, when every other box said 20 microns. Nice thick can, nitrile gasket so I won't be using it on my Subaru in the winter, because I have had them blow out before. But for Spring/Summer/Fall it looks like a nice filter. Made in Taiwan. Has an unusual looking bypass valve. The question is, does it really filter down to 10 microns? Do we even know anything about this filter or who made it? And if it does filter that fine, what efficiency rating? Interestingly enough it is the only filter out of all of the ones they had that listed that small of a micron rating. The Sierra filters can vary a lot in construction and country of origin depending on what application they are for. I have seen USA, Japan, Thailand, Taiwan, China, Mexico, Germany, Tunisia, Malaysia. The Quicksilver filters also sold at West Marine also vary in country of origin. I am a big fan of the 7317-equivalent filter for some of the Honda, Yamaha, Nissan outboards. Very nice soft silicone ADBV, made in Taiwan I believe, metal core with holes, thick can, nice gasket. I use them on the neighbor's QR25DE, as they only cost about 8 dollars and are very good quality. Quicksilver cross reference for this Sierra is listed on top of the box, third picture.
Is this filter really 10 microns? At what efficiency? Or is it a mystery (Sierra Marine 18-7758)
- Thread starter 79Subaru
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All oil filters will remove some 10 micron particles. But if there is no efficiency rating at 10 microns (or any other micron size), then it's anyone's guess. Only way to get any idea is to contact the filter manufacturer to see if they will give efficiency test results.
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As kschachn is apparently fond of saying, even his screen door can filter out some 10 micron particles.
I feel the Polaris (for my new-to-me 450 HO ATV) branded filters are among the same ilk, with a “10 micron filter” claim but literally ZERO other information about it available… plus it’s got nitrile ADBV and thread-end bypass… can you say “Fram Endurance 7317 is a cross-reference” three times fast?
Figured that it probably wasn't anything special. The main reason I got it is the thick can is less likely to get dented being hit by pebbles on the highway (oil filter is right on the front of the engine. Although when you look at some of the Mercury filters that it crosses to they say synthetic media, and all of the other Sierras say 20. The media from what I can see through the holes looks like regular cellulose to me, unless it's some type of blend media like the Premium Guard XL's. Included is a relevant picture of a filter with dents from pebbles. It's also ever so slightly shorter which is a good thing. Just wish more manufacturers would make filters with silicone gaskets. Down to just the Premium Guard XL/STP XL/Pronto XL/Microgard Select. Even the Ford Racing FL820s got rid of their silicone gasket and now just look like regular FL820s.
Without a percent, it's meaningless. Harley Davidson has what they call a 5 micron "Super"Premium5 oil filter. Again, no percent goes with it. Having cut one open though, it is a well-made full synthetic media filter. Or, at least it used to be, by Champ Labs. So, it filters to 5um at some unknown percent.
I will be sure to cut this one open when I am done with it, I am curious myself as I have never seen a bypass that looks anything like the one in this filter. Maybe I will use it next oil change as it hasn't gotten into the super cold months where I really need to use a silicone gasketed filter. I can save the PG4651XL for the winter, then figure out what to buy next. A 5000mi OCI goes quickly at 500-1500mi/week. I'm more than halfway through the current change of M1 5W50 and I can already tell that it's starting to thin out. Hilarious about the Harley filter, not surprised that they would do something like that. Although if this one is just regular cellulose inside, it's arguably worse. Stating 5 microns is just ridiculous though, was just looking at an efficiency chart for a CAT oil filter that sells for over $20. 20% at 4 microns is the lowest the chart goes. They don't sell that as a "4 micron oil filter", just "Advanced High Efficiency", and that chart was a real pain to find, but it did exist. It would be really nice if charts like that were available for every filter. Maybe even directly on the side of the box. It would really provide an incentive for companies to make the best filter they can, and for the ones making mediocre filters to improve them or choose different filter media. Some do at least give some numbers, Fram for example, or Amsoil, as well as the more commercial focused manufacturers like Fleetguard, Donaldson, and in some cases CAT.
It looks like some of the coil spring bypass valves used in some Purolators - see link below. Basically a version of this design. There is probably a coil spring inside that housing you can see through the center tube.
PureOne PL14459 Cut Open (Pixs)
Very thorough job, and crystal clear pics. I have a Classic in the same filter with a 6k OCI. Just draining it now. Will cut open and post pics soon, though not as professional a job as this, I'm sure. Thanks for posting.
bobistheoilguy.com
The one thing that's different, is that the top of that thing you can see, is white plastic. I've never seen anything like it before. Not super clear in the picture, but that's definitely what it is. Not sheet metal. Seen the coil spring bypasses before, both the Purolator and Premium Guard type, never one like this though. It looks almost like some trim piece for a bookshelf, or one of those white plugs that goes in the end of a curtain rod or similar. Although we won't know until I cut it open.
It's probably like the phenolic disk in the Purolator style with the coil spring in my previous link. Something like a disk (of whatever material) needs to make the seal that the coil spring pushes against.
every filter is a 10 micron filter if the efficiency cutoff is low enough.
I recall a scene in Full Metal Jacket where the guys are saying "Without me, my rifle is useless. Without my rifle, I am useless."
That's how we should think of any efficiency without a micron rating and any micron rating without an efficiency. Without one, the other has no purpose.
I recall a scene in Full Metal Jacket where the guys are saying "Without me, my rifle is useless. Without my rifle, I am useless."
That's how we should think of any efficiency without a micron rating and any micron rating without an efficiency. Without one, the other has no purpose.
The "10 micron filter" I use has a normal rating of 9.8micron and 27micron absolute. Problem is normal could mean 97%, 95% or 50%, for Baldwin there "normal rating" appears to be 98.6%.
Absolute is usually fairly universally absolute meaning around 99% to 99.9%.
Absolute is usually fairly universally absolute meaning around 99% to 99.9%.
In the automotive filter industry, "nominal efficiency" typically means 50%, and "absolute efficiency" typically means 98.7% (or round to 99%). I don't think they use the term "normal efficiency".
The Truth About Oil Filter Micron Ratings - ECOGARD
The Truth About Oil Filter Micron Ratings February 27, 2018 / in Cartridge Oil Filters, Oil Filters, Spin-on Oil Filters, Synthetic Oil Filters One of the most commonly asked questions about oil filters for passenger cars and light-duty trucks is “What is the micron rating of the filter?”. The...
www.ecogard.com
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Yeah it seems like 50 to 60% is becoming the norm now and engine oil filter marketing is becoming more like a chess game of calculated lies.
Which is a good argument for using a brand that is more forthcoming and has a better efficiency.
50 to 60% at what micron rating?
As mentioned, to have any real meaning of a filter's efficiency, it needs to list the beta ratio or the efficiency percentage at a specific particle size.
The latest thing is wix down grading quality with their 20 micron rating. Used to be 20 microns at 90 something percent, now it's 20 microns at 50% to 60%. But they appear to be claiming it's still a 20 micron filter.
They don't hit that 90 something percent particle capture till around 30 microns.
If they can sell the same number of filters for the same price and make them 50 cents cheaper, more power to them.