Two purolator boss PBL22500 filters, one with bad louvers one with good, notice the difference to the appearance of the media from the pressure created
Purolator boss, one good louvers, one bad.
- Thread starter guitarandoil67
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I see a bad one and one that’s even worse. 
So, both filters run identical ocis on same the engine, same oil viscosity with same or very close driving/use profile type, ie highway vs local short tripper? Personally, I'd like to see pics of the louvers with the media removed and flashlight taken to them.
Just curious, were the louvers not viewable before purchase and/or use?
Just curious, were the louvers not viewable before purchase and/or use?
Yes, both off a 2012 explorer with around 5k both times. Mobil 1 5w-20
Here is another recent Purolator Boss.. to think this stuff is clearing QC and I imagine the average consumer has no idea and just screws it on.
https://www.mustang7g.com/forums/threads/purolator-boss-oil-filter-quality-control-problem.164928/
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Plenty of flow area, louvers not closed. What I don’t like are the jagged edges of the louvers. The media shaping has nothing to do with the louvers imo.
Dang looks like QC is working from home these days.
So one has been sitting around for a while and the other recently removed? I ask all the questions because you reached the conclusion that media appearance is because of the louvers. Point is there's many variables in that could account for its appearance. To me the media on one looks like it's been subjected to more short trip moisture cycles. Or, 'maybe' just sitting around longer.
'Not that is matters at all', but if I was guessing I'd speculate the one with the better-looking pleats is the one removed more recently. Either way, neither of the media anecdotes looks terrible, just one better than the other.
And the topic filter is a decent size so pre-purchase, pre-use inspection of louvers easier than the smaller ones, in my experience.
Yes, both off a 2012 explorer with around 5k both times. Mobil 1 5w-20
first photo
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Definitely a lot of back pressure going on here. Less opened up louvers leads to wavy pleats
I always recommend close inspection of louvers before use. It’s always hit or miss on the Boss.
I don't think the difference in the louvers effected how the media looked after use. The dP across the media is going to be based on the media, not the louvers. If louvers, holes or an Ecore center tube effected the pressure distribution on the media enough to matter, we'd see a distinct connection between visual media look and the center tube design. But there is no evidence to support that. Center tubes with holes can show perfectly straight pleats, just like with a filter with louvers or an Ecore center tube.
Not really, as explained above - that's a misconception. The difference in dP (ie, differential "back pressure") between those two center tubes in post 1 isn't going to be much. Those louvers in post 1 aren't nearly as bad as some seen. Neither are choked down much differently. The 2nd photo in post 1 looks to have much more "ragged" looking louver slits, but about opened up the same as in photo 1.
Here's a couple of louvered center tubes that would probably put the filter bypass valve in operation way too soon and during most operational conditions due to flow restriction and a resulting dP across the bypass valve.
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4WD
$50 site donor 2025
All of these types of posts should be taken with the media cut away and looking through the louvres in line with the widest view.
That is NEVER when the filter is together or only the can is cut.
That is NEVER when the filter is together or only the can is cut.
It's easy enough to judge how open or closed louvers are by just looking down the center tube at the right angle with a good strong LED flashlight. I get the best visual by looking at the openings down inside the center tube where the louver openings are. Besides, you can't look at them from the backside until the filter has already been ran. Verify they are opened enough before buying or installing the filter.
Pretty easy to tell which one to use and which one not to use.
Pretty easy to tell which one to use and which one not to use.
4WD
$50 site donor 2025
A starting point would be cutting the used filters down to the tube.
Sometimes it’s like window blinds - I look down from a ladder and can’t see the window. I sit on the floor and can easily see the trees.
Further - I have seen a number that face the other way.
Looking inside a new filter is P50 at best.
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Not a scientific conclusion
