Testing flow of used oil filters

rav

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I'm curious, has anyone ever scientifically tested the flow difference on a used oil filter as compared to a new oil filter, to see how much flow is actually affected after 5k or 10k miles?
I've read so many threads about guys complaining about "bad" oil filters but have never seen any testing data. I look at all the cut open filters filtering media pictures & can NOT see any evidence of a clogged-up filter. It would be nice to see some flow data after different miles of filtering oil.
 
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You know, after I paid about $35,000 to $40,000 or more for a vehicle, I want to keep it for a long while. I never understood trying to save a few bucks by running an oil filter for multiple oil changes or running really long oil change intervals. That is just me and I know others feel differently.
 

rav

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You know, after I paid about $35,000 to $40,000 or more for a vehicle, I want to keep it for a long while. I never understood trying to save a few bucks by running an oil filter for multiple oil changes or running really long oil change intervals. That is just me and I know others feel differently.
I understand your point but that's not what I was looking for or asked info on. I'm just an old engineer curious about oil filter flow rates after 5k-10k miles.
 
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Sorry. Did not mean to tramp on your thread. I think the info you are looking for would be very useful, however, for those who do leave filters on for multiple oil changes or for extended oil changes. I just never wanted to take a chance with my vehicles.
 

rav

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Sorry. Did not mean to tramp on your thread. I think the info you are looking for would be very useful, however, for those who do leave filters on for multiple oil changes or for extended oil changes. I just never wanted to take a chance with my vehicles.
I most certainly understand & respect your discission. It is a big investment & needs to be taken care of more than most people want to put the money or efforts into. I'm just curious about how oil filters are affected after...say 5000 miles of filtering. Is it 1% or 80% restricted?
 
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Flow will always happen with the filter bypass. And most likely the bypass valve does operate at startup. There is a pressure differential before and after the filter.


Then there is bypass filtration that takes 5-10% of oil through a higher grade filter. According to this article the bypass oil filter can increase the engine life up to 8 times. The key is the particle size being filtered.
 
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FZ1

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Flow will always happen with the filter bypass. And most likely the bypass valve does operate at startup. There is a pressure differential before and after the filter.


Then there is bypass filtration that takes 5-10% of oil through a higher grade filter. According to this article the bypass oil filter can increase the engine life up to 8 times. The key is the particle size being filtered.
Great article! Thank you!
 
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I most certainly understand & respect your discission. It is a big investment & needs to be taken care of more than most people want to put the money or efforts into. I'm just curious about how oil filters are affected after...say 5000 miles of filtering. Is it 1% or 80% restricted?
To a small amount you can see a increase in oil pressure but the oil temperature throws a wrench into it. If you monitor the oil differential with pressure sensors immediately before and after the filter you can see differential change for a given RPM.
 

FZ1

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Flow will always happen with the filter bypass. And most likely the bypass valve does operate at startup. There is a pressure differential before and after the filter.


Then there is bypass filtration that takes 5-10% of oil through a higher grade filter. According to this article the bypass oil filter can increase the engine life up to 8 times. The key is the particle size being filtered.
Interesting. So is the increased oil pump noise, on start up, in cold weather, with a thicker oil, an indication the filter is in bypass?
 

ZeeOSix

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I'm curious, has anyone ever scientifically tested the flow difference on a used oil filter as compared to a new oil filter, to see how much flow is actually affected after 5k or 10k miles?
I've read so many threads about guys complaining about "bad" oil filters but have never seen any testing data. I look at all the cut open filters filtering media pictures & can NOT see any evidence of a clogged-up filter. It would be nice to see some flow data after different miles of filtering oil.
If you want to see what an oil filter does when it loads up, look at the 3rd graph in this post (link below). Filters loading up with debris causes the delta-p across the filter to increase as the flow is held constant. A PD oil pump ensures a constant flow rate at a fixed RPM. The only time a loaded up filter would cause a decrease in oil flow to the engine is if the PD oil pump hits pressure relief. The filter would have to be very clogged up to make that happen.

In the graph, when the delta-p really starts turning up sharply is when the filter is getting close to 100% loaded. Keep in mind this test is accelerated in order to see the delta-p vs loading and to determine the total holding capacity of the filter. In real use, the delta-p may only increase by a few PSI over the entire OCI depending on how clean the engine is.

 
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ZeeOSix

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So is the increased oil pump noise, on start up, in cold weather, with a thicker oil, an indication the filter is in bypass?
I've never heard an oil pump make noise. Maybe if the oil is so cold that it's not pumpable and the pump is cavitating like crazy and running dry, then it might make noise.
 

FZ1

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If you want to see what an oil filter does when it loads up, look at the 3rd graph in this post (link below). Filters loading up with debris causes the delta-p across the filter to increase as the flow is held constant. A PD oil pump ensures a constant flow rate at a fixed RPM. The only time a loaded up filter would cause a decrease in oil flow to the engine is if the PD oil pump hits pressure relief. The filter would have to be very clogged up to make that happen.

In the graph, when the delta-p really starts turning up sharply is when the filter is getting close to 100% loaded. Keep in mind this test is accelerated in order to see the delta-p vs loading and to determine the total holding capacity of the filter. In real use, the delta-p may only increase by a few PSI over the entire OCI depending on how clean the engine is.

Fascinating info. Thank you.
 

FZ1

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I've never heard an oil pump make noise. Maybe if the oil is so cold that it's not pumpable and the pump is cavitating like crazy and running dry, then it might make noise.
We had a cold stretch in North Texas 2 years ago. I had switched from 0w-20 AFE to 5-20 EP and noticed more NVH on cold start up with the EP. Running 0w-20 PUP now.
 

FZ1

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I've never heard an oil pump make noise. Maybe if the oil is so cold that it's not pumpable and the pump is cavitating like crazy and running dry, then it might make noise.
My closed garage is quiet with little outside noise. I just noticed a difference on cold start up.
 

ZeeOSix

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We had a cold stretch in North Texas 2 years ago. I had switched from 0w-20 AFE to 5-20 EP and noticed more NVH on cold start up with the EP. Running 0w-20 PUP now.
Yes, depending on how cold it is, even just one "W" rating difference can change how the engine reacts during a cold start-up.
 
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If you want to see what an oil filter does when it loads up, look at the 3rd graph in this post (link below). Filters loading up with debris causes the delta-p across the filter to increase as the flow is held constant. A PD oil pump ensures a constant flow rate at a fixed RPM. The only time a loaded up filter would cause a decrease in oil flow to the engine is if the PD oil pump hits pressure relief. The filter would have to be very clogged up to make that happen.

In the graph, when the delta-p really starts turning up sharply is when the filter is getting close to 100% loaded. Keep in mind this test is accelerated in order to see the delta-p vs loading and to determine the total holding capacity of the filter. In real use, the delta-p may only increase by a few PSI over the entire OCI depending on how clean the engine is.

Really good info. Due to the 2 step PSI oil pump cycling on the Skyactiv I decided to play the filter stock.
 
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