Filter Bypass Pressure... Why doesn't this matter?

[ZeeOSix]

Originally Posted by Farnsworth
Unrelated but while searching I ran across this video from Toyota. I see a .01 mm filtration claim or 10 microns. Not by the multi pass test they just say it. Actually they say less than 10 microns which has to mean essentially 10. Still it's less.

https://m.youtube.com/watch?v=j15x1umneYI


Interesting video ... but we all know that just saying a filter will capture particles "down to 10 microns" doesn't mean much unless there is a corresponding efficiency % rating at 10 microns. All oil fitlers can catch 10 micron particles ... some just do it more efficiently than others.

 

[bachman]

As per motorcycle filters and drain back valves / filter orientation or filter designs and quality issues, this topic reminded me of my earlier interest and research about 15 years ago.
I'll post the link as it relates to a short read and some citations.
See about halfway down the page as Filter Bypass and Anti-Drain Back Valves.

https://motorcycleinfo.calsci.com/Filters.html

 

[Job]

Originally Posted by ZeeOSix
Originally Posted by Farnsworth
Unrelated but while searching I ran across this video from Toyota. I see a .01 mm filtration claim or 10 microns. Not by the multi pass test they just say it. Actually they say less than 10 microns which has to mean essentially 10. Still it's less.

https://m.youtube.com/watch?v=j15x1umneYI


Interesting video ... but we all know that just saying a filter will capture particles "down to 10 microns" doesn't mean much unless there is a corresponding efficiency % rating at 10 microns. All oil fitlers can catch 10 micron particles ... some just do it more efficiently than others.


They say filters under 10 microns. Clearly the second filter did not filter all particles in the powder. Even after long cycling the oil stayed dirty. I like what I see and will use Toyota filters from now on. They are not "rock catchers." There are other thoughts about what filter efficiency actually is in real use out there.

 

[tundraotto]

So the ISO rating of 50% for the Toyota filters is an urban legend?

 

[ZeeOSix]

Originally Posted by Farnsworth
Originally Posted by ZeeOSix
Originally Posted by Farnsworth
Unrelated but while searching I ran across this video from Toyota. I see a .01 mm filtration claim or 10 microns. Not by the multi pass test they just say it. Actually they say less than 10 microns which has to mean essentially 10. Still it's less.

https://m.youtube.com/watch?v=j15x1umneYI

Interesting video ... but we all know that just saying a filter will capture particles "down to 10 microns" doesn't mean much unless there is a corresponding efficiency % rating at 10 microns. All oil filters can catch 10 micron particles ... some just do it more efficiently than others.

They say filters under 10 microns. Clearly the second filter did not filter all particles in the powder. Even after long cycling the oil stayed dirty. I like what I see and will use Toyota filters from now on. They are not "rock catchers." There are other thoughts about what filter efficiency actually is in real use out there.


All filters will filter at some level under 10 microns ... question is, at what efficiency.

How do you know those particles they used in the comparison test weren't all 100 microns or larger? They didn't say how big the particles were in their visual filtering test. River_rat's bench testing showed the Toyota filters weren't as good as many of the others he tested.

 

[Mightymouse]

Originally Posted by paulri
But if I get an aftermarket filter that is specified for my engine, then why worry? If the filter manufacturer is doing more than just matching the threads, they are making sure that the filter does meet the OEM specs for bypass, also, aren't they?

Originally Posted by Gebo
This is one reason I only use OEM filters on my cars and OPE.


Originally Posted by ad244
And if so, why is this not a thing we actively worry about?

Can't see how some after market filters that are used for multiple applications can be correct for each application.

 

[tundraotto]

I reckon the bypass pressure has to do with the internal restriction and strength of the filter, and its media, not so much the vehicle. The high bypass PSI of a few filters may be because of variable displacement oil pumps (Subaru & Mazda Skyactiv), that jump to higher pressure on demand.....hence the higher bypass setting, to minimize opening in use.

 

[ZeeOSix]

Originally Posted by Mightymouse
Can't see how some after market filters that are used for multiple applications can be correct for each application.


Most passenger vehicles on the road have pretty similar oiling systems in terms of the oil viscosity used and the volumetric oil flow from the pump. You'll see some special oil filter applications for some reasons, but 98% of the oiling systems are close enough to be able to specify one filter for a 100 different engines applications.

 

[Ded Mazai]

Originally Posted by tundraotto
I reckon the bypass pressure has to do with the internal restriction and strength of the filter, and its media, not so much the vehicle. The high bypass PSI of a few filters may be because of (Subaru & Mazda Skyactiv), that jump to higher pressure on demand.....hence the higher bypass setting, to minimize opening in use.


Is it correct that they have variable displacement oil pumps?

 

[ad244]

I appreciate the discussion guys thanks for the explanation