Virgin Black Magic Light Tests: ST MP7317, Champ PH2835XL

[cptbarkey]

I have a small amount of Supertech MPs and ChampXLs from Walmart and Rockauto for my family fleet, a mixture of cans and cartridge styles. After recent generous cut opens by @Glenda W. and @Sayjac I decided to surgically open a few to make up for teasing them for the black magic tests.

I almost opened 4 different types, but seeing the same results on 2 was enough to satisfy my curiosity. I'm tossing all the cans except the cartridge filters and one Endurance I have for my Ram that doesnt have a bypass valve. I'm not too upset about it as my cost basis was already low, and a case of Pentius just came in to replace the 7317s.

How I tested with a flashlight, in the garage with no room lights.

MP7317, my iPhone wouldnt focus very well because of the blue light. Ruffles are very apparant.

2835XL

 

[thastinger]

I guess the FL820s would suck at this, as they come with pre torn media seemingly.

 

[BrendanC]

ill pay shipping on them

 

[CharlieBauer]

This is a bigger scandal than Purolator tears because you may or may not have ended up with a torn filter and if you did, you probably didn't have bypass for the entire fci.

With these, you are almost guaranteed a bypass and you'll have it for the entire service life of the filter.

 

[Glenda W.]

I have a small amount of Supertech MPs and ChampXLs from Walmart and Rockauto for my family fleet, a mixture of cans and cartridge styles. After recent generous cut opens by @Glenda W. and @Sayjac I decided to surgically open a few to make up for teasing them for the black magic tests.

I almost opened 4 different types, but seeing the same results on 2 was enough to satisfy my curiosity. I'm tossing all the cans except the cartridge filters and one Endurance I have for my Ram that doesnt have a bypass valve. I'm not too upset about it as my cost basis was already low, and a case of Pentius just came in to replace the 7317s.

View attachment 242192

How I tested with a flashlight, in the garage with no room lights.
View attachment 242196
MP7317, my iPhone wouldnt focus very well because of the blue light. Ruffles are very apparant.

View attachment 242195


2835XL

View attachment 242193

Thank you for the contribution!! Great work. Much better than mine.

 

[wpod]

Since that is the higher oil pressure side of the filter would the bypass valve assembly be forced together by the oil pressure ?

 

[CharlieBauer]

Since that is the higher oil pressure side of the filter would the bypass valve assembly be forced together by the oil pressure ?

When the can is intact, apparently there is already 70lbs of pressure trying to seal the gap.

 

[fantastic]

Awesome! Great work on the light test. Now we need to figure out what to make of these cracks. I think it's obviously a QC issue. I'd take a low efficiency filter any day vs straight up cracks that free flow my oil. At least it's getting some filtering.

 

[ZeeOSix]

BITOG has turned into a oil filter mad scientist test organization.

 

[ZeeOSix]

I'm tossing all the cans except the cartridge filters and one Endurance I have for my Ram that doesnt have a bypass valve.

I think that Endurance still has a leaf spring that "seals" with the end cap hole, but no actual bypass valve in the leaf spring.

 

[CharlieBauer]

I think that Endurance still has a leaf spring that "seals" with the end cap hole, but no actually bypass valve in the leaf spring.

In other brands where no bypass is required, the end cap is solid metal. But First Brands wanted to save another cent or two and have the same end cap on both ends of the element.

So now everyone gets a bypass!

 

[CharlieBauer]

Awesome! Great work on the light test. Now we need to figure out what to make of these cracks. I think it's obviously a QC issue. I'd take a low efficiency filter any day vs straight up cracks that free flow my oil. At least it's getting some filtering.

It's not for nothing that prior to ISO testing a filter, the first step is to make sure it does not bypass.

A bypassing filter by definition cannot be tested because the bypass was not a design feature so the test results will be too variable to be repeatable and therefore invalid.

Also many OE filter performance levels (USCAR 95% at 30 microns, Toyota 50% at 20 microns, Mercedes 99% at 38 microns) are clearly trading efficiency for full flow filtering longevity in order to minimize bypass. They've determined that the worst thing is permanent bypass.

 

[ZeeOSix]

So now everyone gets a bypass!

 

[Fair enough]

It's not for nothing that prior to ISO testing a filter, the first step is to make sure it does not bypass.

A bypassing filter by definition cannot be tested because the bypass was not a design feature so the test results will be too variable to be repeatable and therefore invalid.

Also many OE filter performance levels (USCAR 95% at 30 microns, Toyota 50% at 20 microns, Mercedes 99% at 38 microns) are clearly trading efficiency for full flow filtering longevity in order to minimize bypass. They've determined that the worst thing is permanent bypass.

Ascent did the bubble test by putting a cork in the hole where the bypass spring seats. I suppose Fram does the same. So the filter gets a pass. they have to use another filter to do the efficiency test on the whole assembly.

 

[KevinMalone]

I'd take a low efficiency filter any day vs straight up cracks that free flow my oil. At least it's getting some filtering.

Also many OE filter performance levels (USCAR 95% at 30 microns, Toyota 50% at 20 microns, Mercedes 99% at 38 microns) are clearly trading efficiency for full flow filtering longevity in order to minimize bypass. They've determined that the worst thing is permanent bypass.

This is where I stand now after all this drama. I'll take build quality over absolute filter efficiency. I've settled on Denso FTF filters despite their lower filter efficiency. At least they can still make a filter free of defects (for now)

 

[Ronn]

I'd take a low efficiency filter any day vs straight up cracks that free flow my oil. At least it's getting some filtering.

Here we go
Again….
Bypass filtering DELAYED is not BYPASS filtering DENIED.
The calculated 10-15% that’s constantly unfiltered on first pass gets filtered on subsequent pass(ergo “DELAYED”)…and subject to the filtration at 20 microns with a superior filter.
The net effect is a DELAYED filtration in a fraction of the total flow, not an escape of filtration. The filter remains in tact and functioning 100%.
I will take a superior filter with this relatively minuscule leakage, over an inferior one that doesn’t have this issue.

 

[Hatsuwr]

Here we go
Again….
Bypass filtering DELAYED is not BYPASS filtering DENIED.
The calculated 10-15% that’s constantly unfiltered on first pass gets filtered on subsequent pass(ergo “DELAYED”)…and subject to the filtration at 20 microns with a superior filter.
The net effect is a DELAYED filtration in a fraction of the total flow, not an escape of filtration. The filter remains in tact and functioning 100%.
I will take a superior filter with this relatively minuscule leakage, over an inferior one that doesn’t have this issue.

I don't think that's an accurate assessment.

With a lot of simplifications, you can go a bit further into the math. For a given particle size, if we say filter 1 is 70% efficient per pass and has no leaks, while filter 2 is 90% efficient per pass (for the filtered portion) and has a 15% constant bypass, then the percentage of particles remaining after n passes for filter 1 is .3^n, and for filter 2 is .235^n. Filter 2 will always filter better in this scenario.

There are three important points though. First, is that after just 10 passes, even filter 1 fluid would be over 99.99% clean at this particle size.

Second, is that this difference in filtering efficiency will decrease as particle size increases, and above a certain size filter 1 will always be more efficient. Filter 2 will never reach 85% overall efficiency per pass for any particle size.

Finally, when you have startup contaminant surges due to failed retention, those contaminants will tend to have settled closer to the bypass and will be pushed further toward it by the fluid flow, causing that 15% bypass to apply disproportionately higher to the dirtier oil.


All that to say, I would expect that while running normally, the two filters would tend toward equal long term efficiency. However, at startups the perma-bypass filter would allow a higher surge in contaminants that would take longer to filter out to get back to that roughly equal state. One exception could be for very small particles if one of the filters lacks even mild efficiency at that size.

 

[chemman]

With a lot of simplifications, you can go a bit further into the math. For a given particle size, if we say filter 1 is 70% efficient per pass and has no leaks, while filter 2 is 90% efficient per pass (for the filtered portion) and has a 15% constant bypass, then the percentage of particles remaining after n passes for filter 1 is .3^n, and for filter 2 is .235^n. Filter 2 will always filter better in this scenario.

I am curious as to what are and where the 0.3 and 0.235 numbers come from.

 

[Hatsuwr]

I am curious as to what are and where the 0.3 and 0.235 numbers come from.

1-Efficiency*PercentFiltered. So 1-.7 for the first filter, and 1-.9*.85 for the second filter.

So the breakeven point between a normal and a leaky filter would be the particle size at which EfficiencySealed = EfficiencyLeaky * PercentFiltered.

Taking a look at Ascent's chart, the OG Fram Ultra is nearly 100% efficient at the ranges tested. So if it had a 15% permanent bypass, then from the same data, the Al Delco Ultraguard Gold and Royal purple would perform better at all sizes tested (15+ microns), the Purolator Boss would perform better starting at 24 microns or so, and the Wix XP starting at around 30 microns.

 

[chemman]

Thank you!