Great job, Gary! Excellent explanations!!
As always, you have my greatest respect.
As always, you have my greatest respect.
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How often does the bypass valve activate
- Thread starter takax2040
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Another thing I wondered is how much the filter size matters. My Toyota Camry runs a filter that looks like it should be a toy or on a lawnmower. Very small media area that can be 1/2 to 1/3 as much as other filters. Does that mean mine is more likely to go into bypass or does the relief pressure of the filter and pump make the big difference?
Lots of bad info here, as well as overly complicated info.
All that matters is the difference in pressure from the inlet side of the filter to the outlet side. That's all. That's all the relief valve can measure, and that's all it reacts to. (Ditto for GM's oil filter relief valve built into the oil filter mount instead of inside the filter assembly.)
If the pressure drop (differential pressure) across the filter is up to the relief valve's set point, the relief valve will open. When the pressure drop lessens, the relief valve closes. These relief valves are simple and cheap, so don't expect accurate results. The pressure drop through the engine has no relationship to the filter, nor does the oil pressure. Thicker oil has more drop through the filter, so that opens the relief valve, as does dirty media. Increased oil flow will increase the pressure drop, other things remaining equal, and if the oil isn't thin enough will cause the relief valve to open.
Let's call the valve at the oil pump a pressure control valve just so we have terminology that is less confusing. This means nothing to the oil filter relief valve, anyway.
What determines flow through a filter is the number of holes in the filter media, not the total area of the media. If new-tech media has the same number of holes of the right size as old-tech media, it'll filter the same and flow the same.
All that matters is the difference in pressure from the inlet side of the filter to the outlet side. That's all. That's all the relief valve can measure, and that's all it reacts to. (Ditto for GM's oil filter relief valve built into the oil filter mount instead of inside the filter assembly.)
If the pressure drop (differential pressure) across the filter is up to the relief valve's set point, the relief valve will open. When the pressure drop lessens, the relief valve closes. These relief valves are simple and cheap, so don't expect accurate results. The pressure drop through the engine has no relationship to the filter, nor does the oil pressure. Thicker oil has more drop through the filter, so that opens the relief valve, as does dirty media. Increased oil flow will increase the pressure drop, other things remaining equal, and if the oil isn't thin enough will cause the relief valve to open.
Let's call the valve at the oil pump a pressure control valve just so we have terminology that is less confusing. This means nothing to the oil filter relief valve, anyway.
What determines flow through a filter is the number of holes in the filter media, not the total area of the media. If new-tech media has the same number of holes of the right size as old-tech media, it'll filter the same and flow the same.
Originally Posted By: Ken2
Lots of bad info here, as well as overly complicated info.
All that matters is the difference in pressure from the inlet side of the filter to the outlet side. That's all. That's all the relief valve can measure, and that's all it reacts to. (Ditto for GM's oil filter relief valve built into the oil filter mount instead of inside the filter assembly.)
True ... but as mentioned there are MANY factors that determine exactly what the PSID is across the media / bypass valve. It is more complicated when you realize how many factors there are.
Originally Posted By: Ken2
If the pressure drop (differential pressure) across the filter is up to the relief valve's set point, the relief valve will open. When the pressure drop lessens, the relief valve closes. These relief valves are simple and cheap, so don't expect accurate results. The pressure drop through the engine has no relationship to the filter, nor does the oil pressure. Thicker oil has more drop through the filter, so that opens the relief valve, as does dirty media. Increased oil flow will increase the pressure drop, other things remaining equal, and if the oil isn't thin enough will cause the relief valve to open.
Comment about your text in red above. For sure the pressure drop is related to the filter's design and to the oil pressure. If the filter is designed to be restrictive to flow the bypass valve will open easier & more often than if it was a free flowing filter. The oil pressure is what causes the oil volume to flow ... so more oil pressure will increase oil flow which in turn will increase PSID. Like I said, there are many factors involved.
Originally Posted By: Ken2
Let's call the valve at the oil pump a pressure control valve just so we have terminology that is less confusing. This means nothing to the oil filter relief valve, anyway.
True ... I've mentioned that many times. Some people don't believe this, but they are "off base" and don't really understand the total oiling system dynamics.
Originally Posted By: Ken2
What determines flow through a filter is the number of holes in the filter media, not the total area of the media. If new-tech media has the same number of holes of the right size as old-tech media, it'll filter the same and flow the same.
Technically both are a factor. It's the combination of the media used, and the total area of the media.
Lots of bad info here, as well as overly complicated info.
All that matters is the difference in pressure from the inlet side of the filter to the outlet side. That's all. That's all the relief valve can measure, and that's all it reacts to. (Ditto for GM's oil filter relief valve built into the oil filter mount instead of inside the filter assembly.)
True ... but as mentioned there are MANY factors that determine exactly what the PSID is across the media / bypass valve. It is more complicated when you realize how many factors there are.
Originally Posted By: Ken2
If the pressure drop (differential pressure) across the filter is up to the relief valve's set point, the relief valve will open. When the pressure drop lessens, the relief valve closes. These relief valves are simple and cheap, so don't expect accurate results. The pressure drop through the engine has no relationship to the filter, nor does the oil pressure. Thicker oil has more drop through the filter, so that opens the relief valve, as does dirty media. Increased oil flow will increase the pressure drop, other things remaining equal, and if the oil isn't thin enough will cause the relief valve to open.
Comment about your text in red above. For sure the pressure drop is related to the filter's design and to the oil pressure. If the filter is designed to be restrictive to flow the bypass valve will open easier & more often than if it was a free flowing filter. The oil pressure is what causes the oil volume to flow ... so more oil pressure will increase oil flow which in turn will increase PSID. Like I said, there are many factors involved.
Originally Posted By: Ken2
Let's call the valve at the oil pump a pressure control valve just so we have terminology that is less confusing. This means nothing to the oil filter relief valve, anyway.
True ... I've mentioned that many times. Some people don't believe this, but they are "off base" and don't really understand the total oiling system dynamics.
Originally Posted By: Ken2
What determines flow through a filter is the number of holes in the filter media, not the total area of the media. If new-tech media has the same number of holes of the right size as old-tech media, it'll filter the same and flow the same.
Technically both are a factor. It's the combination of the media used, and the total area of the media.
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The pressure drop through the engine has no relationship to the filter, nor does the oil pressure.
I agree and disagree with this unqualified statement.
Quote:
Thicker oil has more drop through the filter
Only to the point where it also has and equally proportional elevated pressure drop across the engine. Which ..anyone will concede ..is TREMENDOUS.
Again, just practical common sense without any fancy gauges for "proof". Anyone with a gauge can figure whether or not they have a sender/sensor above or below the filter. If you know your relief limit ..or can find it out (should not be too much of a challenge for most who ponder the topic), you should be able to see how close the downstream pressure is to the relief. Anyone should have the wits about them to observe the pressure if they're into this depth of contemplation.
Have an 85lb relief? Ever see 83lbs? Guess what the filter is seeing at that moment. No reason to figure (outside of those who cling to the romance of high volume where the media can be taxed for throughput capacity for whatever jollies it brings them) that it should be ANY MORE as the pressure retreats across the engine or the volume changes (any argument with a volume vs. visc/temp exchange?) without the regulator being engaged.
Any problem with that? If so, tell me when you would expect the PSID across the filter to INCREASE with decreased visc and or/volume? (again at the qualified no-regulator event).
So, under this logic chain. We don't need a whole lot of intricate data or devices to reason this very simply.
Quote:
Thicker oil has more drop through the filter
At what time? Is the engine fully enveloped at that time? Is the engine side of the filter void of oil?
Unqualified.
If the engine is mostly enveloped with oil ..THICK oil, the action is the same kinetic bumper cars. The filter will still NOT BE THERE. Will not, outside of a "pressure regulator" event, there be one molecule of oil directly pushing on one molecule of oil at each and every pore of the media WITH NO CHOICE BUT TO MOVE? Without a relief event, in an enveloped engine ..at any point of pressure measurement be in ratio to the total system resistance (sensible volumes for those not married to Fast and Furious).
No change in volume ..no regulator event UNTIL the "back pressure" (call it what you want ) forces it.
Engine NOT fully enveloped? Sure, now there can be a filter bypass event if the unregulated (no pressure regulation at the pump) oil flow has not YET produced pressure (or as high a pressure) on the engine side of the filter. Now before we get ahead of ourselves, don't suggest that the media ..with it's (up to) 25lb relief limit, will ...all by itself trigger a pressure regulation event at the pump.
Quote:
pressure control valve just so we have terminology that is less confusing. This means nothing to the oil filter relief valve, anyway.
This I totally disagree with. While loading or high volume (some appear to like "hot oil" associated with that term) can tax the media for throughput and develop higher PSID ..but that's nothing compared to what most see on a day to day basis.
Ken: Riddle me this. Others will usually tap dance around it ..but let's see if you can keep this in my terms so that it isn't "fogged".
Lets say we have an 85lb relief limit ...and we've verified it ..factory called us up to thank us for our interest. The engineer that designed it told us how he came up with the number.
We also know we have an engine side gauge. It's been IS0 and FDA/EPA/DOD/FBI/NSA/CIA certified as being accurate.
We go out to our car ..and we can't tell the temp. We know we have oil in our car, but we don't know the visc ..since we don't know the temp. We don't care.
We turn on the car and the oil pressure gauge goes to 72 PSI.
What does that tell you about the PSID that the filter is seeing?
What does that tell you about the volume that the engine is seeing?
A: The filter MUST be seeing 13PSID.
A: That the pump is in pressure control and that the engine is not seeing 100% of the sensible pump output.
Visc and volume don't even need to be figured here.
Any arguments should be presented in a manner that attempts to change the point of view by dismantling the examples. Not with dancing around in unlike terms.
The pressure drop through the engine has no relationship to the filter, nor does the oil pressure.
I agree and disagree with this unqualified statement.
Quote:
Thicker oil has more drop through the filter
Only to the point where it also has and equally proportional elevated pressure drop across the engine. Which ..anyone will concede ..is TREMENDOUS.
Again, just practical common sense without any fancy gauges for "proof". Anyone with a gauge can figure whether or not they have a sender/sensor above or below the filter. If you know your relief limit ..or can find it out (should not be too much of a challenge for most who ponder the topic), you should be able to see how close the downstream pressure is to the relief. Anyone should have the wits about them to observe the pressure if they're into this depth of contemplation.
Have an 85lb relief? Ever see 83lbs? Guess what the filter is seeing at that moment. No reason to figure (outside of those who cling to the romance of high volume where the media can be taxed for throughput capacity for whatever jollies it brings them) that it should be ANY MORE as the pressure retreats across the engine or the volume changes (any argument with a volume vs. visc/temp exchange?) without the regulator being engaged.
Any problem with that? If so, tell me when you would expect the PSID across the filter to INCREASE with decreased visc and or/volume? (again at the qualified no-regulator event).
So, under this logic chain. We don't need a whole lot of intricate data or devices to reason this very simply.
Quote:
Thicker oil has more drop through the filter
At what time? Is the engine fully enveloped at that time? Is the engine side of the filter void of oil?
Unqualified.
If the engine is mostly enveloped with oil ..THICK oil, the action is the same kinetic bumper cars. The filter will still NOT BE THERE. Will not, outside of a "pressure regulator" event, there be one molecule of oil directly pushing on one molecule of oil at each and every pore of the media WITH NO CHOICE BUT TO MOVE? Without a relief event, in an enveloped engine ..at any point of pressure measurement be in ratio to the total system resistance (sensible volumes for those not married to Fast and Furious).
No change in volume ..no regulator event UNTIL the "back pressure" (call it what you want ) forces it.
Engine NOT fully enveloped? Sure, now there can be a filter bypass event if the unregulated (no pressure regulation at the pump) oil flow has not YET produced pressure (or as high a pressure) on the engine side of the filter. Now before we get ahead of ourselves, don't suggest that the media ..with it's (up to) 25lb relief limit, will ...all by itself trigger a pressure regulation event at the pump.
Quote:
pressure control valve just so we have terminology that is less confusing. This means nothing to the oil filter relief valve, anyway.
This I totally disagree with. While loading or high volume (some appear to like "hot oil" associated with that term) can tax the media for throughput and develop higher PSID ..but that's nothing compared to what most see on a day to day basis.
Ken: Riddle me this. Others will usually tap dance around it ..but let's see if you can keep this in my terms so that it isn't "fogged".
Lets say we have an 85lb relief limit ...and we've verified it ..factory called us up to thank us for our interest. The engineer that designed it told us how he came up with the number.
We also know we have an engine side gauge. It's been IS0 and FDA/EPA/DOD/FBI/NSA/CIA certified as being accurate.
We go out to our car ..and we can't tell the temp. We know we have oil in our car, but we don't know the visc ..since we don't know the temp. We don't care.
We turn on the car and the oil pressure gauge goes to 72 PSI.
What does that tell you about the PSID that the filter is seeing?
What does that tell you about the volume that the engine is seeing?
A: The filter MUST be seeing 13PSID.
A: That the pump is in pressure control and that the engine is not seeing 100% of the sensible pump output.
Visc and volume don't even need to be figured here.
Any arguments should be presented in a manner that attempts to change the point of view by dismantling the examples. Not with dancing around in unlike terms.
"We turn on the car and the oil pressure gauge goes to 72 PSI.
What does that tell you about the PSID that the filter is seeing?
What does that tell you about the volume that the engine is seeing?
A: The filter MUST be seeing 13PSID. "
Bzzzt, not really.
I take it that in your hypothetical the engine oil pressure gauge after the oil filter. This still doesn't tell us the pressure drop across the filter (PSID). We don't know if the oil pump's pressure relief valve was in its open/operating state or if the oil pump was putting out something below 85 PSI and therefore the 85 PSI relief valve was closed. From your hypthetical one could conclude that the pressure drop between the output of the oil pump and the oil pressure sender tap point was likely no more than 13 PSI (assuming perfect accuracy everywhere), but we don't know the actual drop. You either need single ended instruments on both sides of the filter to know the actual pressure drop, or a differential pressure measurement across the two points (like using two voltmeters referenced to ground or one voltmeter across the element in question).
Also, just because the design target is 85 doesn't mean that your particular vehicle is pressure limited right at 85. Maybe yours is 83, maybe 86. Tolerances, eh?
"Any arguments should be presented in a manner that attempts to change the point of view by dismantling the examples. Not with dancing around in unlike terms."
Wow, much ego going on here? Just what does "attempts to change the point of view" mean?
What does that tell you about the PSID that the filter is seeing?
What does that tell you about the volume that the engine is seeing?
A: The filter MUST be seeing 13PSID. "
Bzzzt, not really.
I take it that in your hypothetical the engine oil pressure gauge after the oil filter. This still doesn't tell us the pressure drop across the filter (PSID). We don't know if the oil pump's pressure relief valve was in its open/operating state or if the oil pump was putting out something below 85 PSI and therefore the 85 PSI relief valve was closed. From your hypthetical one could conclude that the pressure drop between the output of the oil pump and the oil pressure sender tap point was likely no more than 13 PSI (assuming perfect accuracy everywhere), but we don't know the actual drop. You either need single ended instruments on both sides of the filter to know the actual pressure drop, or a differential pressure measurement across the two points (like using two voltmeters referenced to ground or one voltmeter across the element in question).
Also, just because the design target is 85 doesn't mean that your particular vehicle is pressure limited right at 85. Maybe yours is 83, maybe 86. Tolerances, eh?
"Any arguments should be presented in a manner that attempts to change the point of view by dismantling the examples. Not with dancing around in unlike terms."
Wow, much ego going on here? Just what does "attempts to change the point of view" mean?
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Quote:
Bzzzt, not really.
Okay ..we'll do it pony style.
It's -30 and you just put in 15w-40 (IOW make it fit what it's trying to demonstrate or continue the senseless waste of confounding and avoiding saying "yes, you're correct")
seeking of holes.
Quote:
You either need single ended instruments on both sides of the filter to know the actual pressure drop, or a differential pressure measurement across the two points (like using two voltmeters referenced to ground or one voltmeter across the element in question).
I've had these and people still challenge my observations. I was "trying" (see the difficulty in "cooperative" discovery even if it led to my changing my mind?) to work it so that those who did not have such things could reason this.
Quote:
Also, just because the design target is 85 doesn't mean that your particular vehicle is pressure limited right at 85. Maybe yours is 83, maybe 86. Tolerances, eh?
Like here. I tried to eliminate just such conjecture to move the discussion forward, yet you ignored the CIA/ISO/FBI/engineer/confirmed by the factory and insisted on removing your need to cope with it "as stated".
This is the "creative arguing" that confounds much of what can be achieved here. It's becoming the norm around here.
seeking of holes.
Quote:
Wow, much ego going on here? Just what does "attempts to change the point of view" mean?
None at all. Suppose I'm a moron and can't see what you're saying in the manner you're saying it? If you're so generous and lack any need to glorify yourself, step down to my level and show me the error of my ways.
Let's try and avoid "creative arguing for the sake of self glorification" ..and merely seek to see what the others sees ..and we do not.
If everyone would stop seeking "holes" to crawl through, I think we could settle this.
Bzzzt, not really.
Okay ..we'll do it pony style.
It's -30 and you just put in 15w-40 (IOW make it fit what it's trying to demonstrate or continue the senseless waste of confounding and avoiding saying "yes, you're correct")
seeking of holes.
Quote:
You either need single ended instruments on both sides of the filter to know the actual pressure drop, or a differential pressure measurement across the two points (like using two voltmeters referenced to ground or one voltmeter across the element in question).
I've had these and people still challenge my observations. I was "trying" (see the difficulty in "cooperative" discovery even if it led to my changing my mind?) to work it so that those who did not have such things could reason this.
Quote:
Also, just because the design target is 85 doesn't mean that your particular vehicle is pressure limited right at 85. Maybe yours is 83, maybe 86. Tolerances, eh?
Like here. I tried to eliminate just such conjecture to move the discussion forward, yet you ignored the CIA/ISO/FBI/engineer/confirmed by the factory and insisted on removing your need to cope with it "as stated".
This is the "creative arguing" that confounds much of what can be achieved here. It's becoming the norm around here.
seeking of holes.
Quote:
Wow, much ego going on here? Just what does "attempts to change the point of view" mean?
None at all. Suppose I'm a moron and can't see what you're saying in the manner you're saying it? If you're so generous and lack any need to glorify yourself, step down to my level and show me the error of my ways.
Let's try and avoid "creative arguing for the sake of self glorification" ..and merely seek to see what the others sees ..and we do not.
If everyone would stop seeking "holes" to crawl through, I think we could settle this.
Originally Posted By: wgtoys
I take it that in your hypothetical the engine oil pressure gauge after the oil filter. This still doesn't tell us the pressure drop across the filter (PSID). We don't know if the oil pump's pressure relief valve was in its open/operating state or if the oil pump was putting out something below 85 PSI and therefore the 85 PSI relief valve was closed. From your hypthetical one could conclude that the pressure drop between the output of the oil pump and the oil pressure sender tap point was likely no more than 13 PSI (assuming perfect accuracy everywhere), but we don't know the actual drop. You either need single ended instruments on both sides of the filter to know the actual pressure drop, or a differential pressure measurement across the two points (like using two voltmeters referenced to ground or one voltmeter across the element in question).
True ... the best way to determine the actual PSID across the filter under any operating condition would be to actually measure it.
But ... the example above was to show that IF the oil pump was in pressure relief at say 85 psi (and ideally constant), and the oil pressure sensor located after the filter read 72 psi, then there would be a 13 PSID across the filter. If a less restrictive filter was used under the same conditions, the oil pressure gauge might read 76 psi with the pump at pressure relief of 85 psi, which would mean the filter PSID would be 9 psi.
I take it that in your hypothetical the engine oil pressure gauge after the oil filter. This still doesn't tell us the pressure drop across the filter (PSID). We don't know if the oil pump's pressure relief valve was in its open/operating state or if the oil pump was putting out something below 85 PSI and therefore the 85 PSI relief valve was closed. From your hypthetical one could conclude that the pressure drop between the output of the oil pump and the oil pressure sender tap point was likely no more than 13 PSI (assuming perfect accuracy everywhere), but we don't know the actual drop. You either need single ended instruments on both sides of the filter to know the actual pressure drop, or a differential pressure measurement across the two points (like using two voltmeters referenced to ground or one voltmeter across the element in question).
True ... the best way to determine the actual PSID across the filter under any operating condition would be to actually measure it.
But ... the example above was to show that IF the oil pump was in pressure relief at say 85 psi (and ideally constant), and the oil pressure sensor located after the filter read 72 psi, then there would be a 13 PSID across the filter. If a less restrictive filter was used under the same conditions, the oil pressure gauge might read 76 psi with the pump at pressure relief of 85 psi, which would mean the filter PSID would be 9 psi.
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