your oil filter preference

[thstone]

With the above being said ^^^, I understand that my experience is not representative of all engines.

However, in reality, doesn't the oil that goes thru the bypass get filtered the next time thru? Even if the bypass was permanent, isn't the turnover rate high enough such that it wouldn't take long for all of the oil (and all of the contaminants) to have passed thru the filter?

What I mean is first pass, 20% unfiltered. 2nd pass 20% of the first 20% is bypassed (0.04%). By the third pass, 20% x 20% x 20%, only 0.008% of the oil is unfiltered. Very quickly, the amount of unfiltered oil approaches zero and any new contaminants are also quickly filtered out in only a handful of turnovers.

Or am I missing something?

[Fyeganeh]

Originally Posted by thstone

With the above being said ^^^, I understand that my experience is not representative of all engines.

However, in reality, doesn't the oil that goes thru the bypass get filtered the next time thru? Even if the bypass was permanent, isn't the turnover rate high enough such that it wouldn't take long for all of the oil (and all of the contaminants) to have passed thru the filter?

What I mean is first pass, 20% unfiltered. 2nd pass 20% of the first 20% is bypassed (0.04%). By the third pass, 20% x 20% x 20%, only 0.008% of the oil is unfiltered. Very quickly, the amount of unfiltered oil approaches zero and any new contaminants are also quickly filtered out in only a handful of turnovers.

Or am I missing something?

You mean 20% then 4% and then 0.8% and so on. Same idea.

[JFP in PA]

Originally Posted by thstone

With the above being said ^^^, I understand that my experience is not representative of all engines.

However, in reality, doesn't the oil that goes thru the bypass get filtered the next time thru? Even if the bypass was permanent, isn't the turnover rate high enough such that it wouldn't take long for all of the oil (and all of the contaminants) to have passed thru the filter?

What I mean is first pass, 20% unfiltered. 2nd pass 20% of the first 20% is bypassed (0.04%). By the third pass, 20% x 20% x 20%, only 0.008% of the oil is unfiltered. Very quickly, the amount of unfiltered oil approaches zero and any new contaminants are also quickly filtered out in only a handful of turnovers.

Or am I missing something?

Problem remains that as long as there is any bypass, particulate matter is getting fed into the main oil galleries feeding the rods and mains; which is never a good thing.

[911monty]

Originally Posted by thstone

With the above being said ^^^, I understand that my experience is not representative of all engines.

However, in reality, doesn't the oil that goes thru the bypass get filtered the next time thru? Even if the bypass was permanent, isn't the turnover rate high enough such that it wouldn't take long for all of the oil (and all of the contaminants) to have passed thru the filter?

What I mean is first pass, 20% unfiltered. 2nd pass 20% of the first 20% is bypassed (0.04%). By the third pass, 20% x 20% x 20%, only 0.008% of the oil is unfiltered. Very quickly, the amount of unfiltered oil approaches zero and any new contaminants are also quickly filtered out in only a handful of turnovers.

Or am I missing something?

thstone I hope we could all have high mileage vehicles that simply wear out but most will probably never see those mileages. So trying to prevent the myriad of engine failure causes is probably more of a concern.

As far as eventual filtering is concerned as long as the filter bypass (excellent terminology) is open, oil is not being filtered. This is due to fluid flow(oil) will be to path of least resistance which is though the bypass and not the restriction of the media.
Once the bypass closes then your calculation is effected by the beta efficiency of the filter which for the WIX/NAPA filter is 95% of 20 micron and 50% of 2 micron particles on first pass. SO unless your engine never generates any debris there will always be material, especially in the <20 micron range.
While the greatest engine wear occurs on dry startup, some percentage of the remaining wear could be attributed to the abrasive wear caused by the <20 micron particles. If we can remove the metallic component from this debris maybe we can reduce the more abrasive component.
Lastly what caused the lifter failure of your engine? Plugging and stuck? If so then perhaps 50 % of your engine failures were due to circulating debris. Wore out lifter carrier! Anyway only the best for my car and if this helps then I won't have to have my daddy buy me another one! Win WIN!