ZeeOSix is correct this time. People misunderstand the center tube's role. It has no direct sealing function (It's full of holes, after all!), although it might play a structural role in some designs.
[Cut Open] Honda 15400-PLM-A02 (Fram) - Virgin
- Thread starter DuckRyder
- Start date
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The center tube is the main structural element between the baseplate and dome end spring. On my Baldwins with media showing, the gap doesn't go all the way around. The filter will still be rigid enough to not come loose inside by contacting part of the center tube. I asked that on this one, if the gap goes all around. Media alone is usually not very rigid. Looking at used filters wavy elements, especially OC's it isn't even something that should be thought of as a structural element. Media is not a spring. I saw the impression on the felt right away, that's why I said this media is strong enough to do that. Doesn't mean much as the filter isn't used. Actually I said this in my first post that the media has some strength. Most OCOD's etc are sparse on media, wavy and bent like all get out. To say that wavy paper is structural is total nonsense. It's a big defect on this Fram product, no excuses. If I was the maker I would apologize for your trouble, say it is a defect, and find out why the tubes aren't as designed.
It does have a gap all the way around, though it is slightly narrower at the seam...
And here’s a detail - it is not fixed - on all 3 filters the center tube is floating between the end caps.
We do see slightly deformed end caps on these after some miles:
Honda 15400-PLM-A02 (Honeywell) ~7500 M
(I note from that thread we’ve been down this road at least partially before.)
So bear with me here:
If the media is sealed to the end caps...
And the center tube is long enough that it keeps the media from collapsing...
And the center tube is long enough to allow the spring to exert sufficient tension on the end caps to seal the bypass and anti drain back valves...
How does the slight gap shown create a bypass?
I stipulate that if the center tube is so short as to allow the assembly to no longer be under tension or the media to displace to a degree sufficient to allow deformation of the end cap or media to break the seal between either the leaf spring/bypass or ADBV (edit: and the end cap) that is an issue...
But, I submit that the end caps are the sealing surface, not the center tube. The fiber ring on the XG element seems to support this as well.
And here’s a detail - it is not fixed - on all 3 filters the center tube is floating between the end caps.
We do see slightly deformed end caps on these after some miles:
Honda 15400-PLM-A02 (Honeywell) ~7500 M
(I note from that thread we’ve been down this road at least partially before.)
So bear with me here:
If the media is sealed to the end caps...
And the center tube is long enough that it keeps the media from collapsing...
And the center tube is long enough to allow the spring to exert sufficient tension on the end caps to seal the bypass and anti drain back valves...
How does the slight gap shown create a bypass?
I stipulate that if the center tube is so short as to allow the assembly to no longer be under tension or the media to displace to a degree sufficient to allow deformation of the end cap or media to break the seal between either the leaf spring/bypass or ADBV (edit: and the end cap) that is an issue...
But, I submit that the end caps are the sealing surface, not the center tube. The fiber ring on the XG element seems to support this as well.
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Originally Posted By: goodtimes
The center tube is the main structural element between the baseplate and dome end spring. ... Media alone is usually not very rigid. ...
On my cartridge filters, the media itself is the ONLY structural element resisting the end caps being compressed together by the spring (which exerts roughly 7 pounds constant force against the filter). I've used 3 different brands so far, and none have collapsed at all. There's a center tube built into the cap, but it carries no axial loading. The insides of a spin-on are not that different.
The center tube is the main structural element between the baseplate and dome end spring. ... Media alone is usually not very rigid. ...
On my cartridge filters, the media itself is the ONLY structural element resisting the end caps being compressed together by the spring (which exerts roughly 7 pounds constant force against the filter). I've used 3 different brands so far, and none have collapsed at all. There's a center tube built into the cap, but it carries no axial loading. The insides of a spin-on are not that different.
Using the newest pics posted above, 'if' they were to represent the condition of the filter and placement of the endcaps at some point 'during the oci', then oil would be bypassing unfiltered oil at the 12 o'clock in first pic, and 10-11 o'clock position in the second. Less likely in the second because the nitrile/silicone adbv might maintain enough of a seal between inlet dirty oil and outlet clean side by covering the endcap gap shown.
That said, with tight uniform pleating and the pressure from the compression/leaf spring could possibly keep those areas covered during the fci as the indention marks indicate. Still imo, it's preferable to see the ends of the centertube completely covered at least in post use dissections.
Otoh, the pics from this thread show what can happen with something less than tight uniform pleating and fiber endcaps, TG in this case. Oil bypass area clearly visible. In the first the gap area is in bypass. The second and third shows how the previously mentioned pleat deformation can uncover the seal area of centertube end and endcap in the area of the pleat deformation. In this case though the more severe and obvious bypass area is the gap shown in first pic. And it's not caused by 'glazed oil' at
That said, with tight uniform pleating and the pressure from the compression/leaf spring could possibly keep those areas covered during the fci as the indention marks indicate. Still imo, it's preferable to see the ends of the centertube completely covered at least in post use dissections.
Otoh, the pics from this thread show what can happen with something less than tight uniform pleating and fiber endcaps, TG in this case. Oil bypass area clearly visible. In the first the gap area is in bypass. The second and third shows how the previously mentioned pleat deformation can uncover the seal area of centertube end and endcap in the area of the pleat deformation. In this case though the more severe and obvious bypass area is the gap shown in first pic. And it's not caused by 'glazed oil' at
Originally Posted By: CR94
Originally Posted By: goodtimes
The center tube is the main structural element between the baseplate and dome end spring. ... Media alone is usually not very rigid. ...
On my cartridge filters, the media itself is the ONLY structural element resisting the end caps being compressed together by the spring (which exerts roughly 7 pounds constant force against the filter). I've used 3 different brands so far, and none have collapsed at all. There's a center tube built into the cap, but it carries no axial loading. The insides of a spin-on are not that different.
Like I said there is a can filter called IAP which doesn't use the tube as the structural element. So cases exist. That filter has a very strong media. Fram EG's and so on already have bent pleats even with the full center tube. There is almost zero strength axially on those. If the tube was 1/4" short like someone stated is OK, it would fail. If one of your aftermarket filters isn't made rigid enough, when it collapses slightly you are going to be in bypass all the time. On the filter pictured here the gap, center tube cut short, is a defect.
Originally Posted By: goodtimes
The center tube is the main structural element between the baseplate and dome end spring. ... Media alone is usually not very rigid. ...
On my cartridge filters, the media itself is the ONLY structural element resisting the end caps being compressed together by the spring (which exerts roughly 7 pounds constant force against the filter). I've used 3 different brands so far, and none have collapsed at all. There's a center tube built into the cap, but it carries no axial loading. The insides of a spin-on are not that different.
Like I said there is a can filter called IAP which doesn't use the tube as the structural element. So cases exist. That filter has a very strong media. Fram EG's and so on already have bent pleats even with the full center tube. There is almost zero strength axially on those. If the tube was 1/4" short like someone stated is OK, it would fail. If one of your aftermarket filters isn't made rigid enough, when it collapses slightly you are going to be in bypass all the time. On the filter pictured here the gap, center tube cut short, is a defect.
Obviously, if pleats are super spaced out all kinds of issues can happen. Every filter - regardless of brand - showing some kind of issue after use seem to have wide spaced pleats ... except for the wire backed synthetic media crowd don't show issues from wide pleats for obvious reasons.
As far as if slightly short center tubes causing issues or not, I've seen zero actual evidence from all the cut open filters posted here for the last 8 years that it's an issue and causes any kind of failure. It being a so called problem is a biased misconception.
As far as if slightly short center tubes causing issues or not, I've seen zero actual evidence from all the cut open filters posted here for the last 8 years that it's an issue and causes any kind of failure. It being a so called problem is a biased misconception.
Originally Posted By: Sayjac
Using the newest pics posted above, 'if' they were to represent the condition of the filter and placement of the endcaps at some point 'during the oci', then oil would be bypassing unfiltered oil at the 12 o'clock in first pic, and 10-11 o'clock position in the second. Less likely in the second because the nitrile/silicone adbv might maintain enough of a seal between inlet dirty oil and outlet clean side by covering the endcap gap shown.
That said, with tight uniform pleating and the pressure from the compression/leaf spring could possibly keep those areas covered during the fci as the indention marks indicate. Still imo, it’s preferable to see the ends of the centertube completely covered at least in post use dissections.
I think we may at least be in the same book, if perhaps not exactly the same page.
I don’t believe that filter element is in bypass even IF that is the way it was when assembled (which it wasn’t because of the leaf/bypass). Unfortunately I no longer have that element, but let us look at this for a minute. (This isn’t directed at you, I’m just trying to explain my case)
The media is bonded to each end cap - Right?
If the media is bonded to the end caps the only way from the dirty to the clean side either through the media or around the end cap - Right?
So, if the leaf spring / bypass assembly and ADBV are sealed to the end caps, the only way from the clean to dirty side is through the media - Right?
If the media and end caps were completely rigid (I know they are not) THEN the center tube would be unnecessary - Right?
So my contention is that the end caps are the sealing surface, not the center tube. The center tube provides support for the media, but it doesn’t alter the path through the media...
Originally Posted By: Sayjac
Otoh, the pics from this thread show what can happen with something less than tight uniform pleating and fiber endcaps, TG in this case. Oil bypass area clearly visible. In the first the gap area is in bypass. The second and third shows how the previously mentioned pleat deformation can uncover the seal area of centertube end and endcap in the area of the pleat deformation. In this case though the more severe and obvious bypass area is the gap shown in first pic. And it's not caused by 'glazed oil' at
That one is a problem... but it wasn’t in bypass until the end cap pulled away from the ADBV or leaf spring (it actually looks like it pulled away from both in some of the thread photos).
Using the newest pics posted above, 'if' they were to represent the condition of the filter and placement of the endcaps at some point 'during the oci', then oil would be bypassing unfiltered oil at the 12 o'clock in first pic, and 10-11 o'clock position in the second. Less likely in the second because the nitrile/silicone adbv might maintain enough of a seal between inlet dirty oil and outlet clean side by covering the endcap gap shown.
That said, with tight uniform pleating and the pressure from the compression/leaf spring could possibly keep those areas covered during the fci as the indention marks indicate. Still imo, it’s preferable to see the ends of the centertube completely covered at least in post use dissections.
I think we may at least be in the same book, if perhaps not exactly the same page.
I don’t believe that filter element is in bypass even IF that is the way it was when assembled (which it wasn’t because of the leaf/bypass). Unfortunately I no longer have that element, but let us look at this for a minute. (This isn’t directed at you, I’m just trying to explain my case)
The media is bonded to each end cap - Right?
If the media is bonded to the end caps the only way from the dirty to the clean side either through the media or around the end cap - Right?
So, if the leaf spring / bypass assembly and ADBV are sealed to the end caps, the only way from the clean to dirty side is through the media - Right?
If the media and end caps were completely rigid (I know they are not) THEN the center tube would be unnecessary - Right?
So my contention is that the end caps are the sealing surface, not the center tube. The center tube provides support for the media, but it doesn’t alter the path through the media...
Originally Posted By: Sayjac
Otoh, the pics from this thread show what can happen with something less than tight uniform pleating and fiber endcaps, TG in this case. Oil bypass area clearly visible. In the first the gap area is in bypass. The second and third shows how the previously mentioned pleat deformation can uncover the seal area of centertube end and endcap in the area of the pleat deformation. In this case though the more severe and obvious bypass area is the gap shown in first pic. And it's not caused by 'glazed oil' at
That one is a problem... but it wasn’t in bypass until the end cap pulled away from the ADBV or leaf spring (it actually looks like it pulled away from both in some of the thread photos).
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Originally Posted By: Sayjac
Using the newest pics posted above, 'if' they were to represent the condition of the filter and placement of the endcaps at some point 'during the oci', then oil would be bypassing unfiltered oil at the 12 o'clock in first pic, and 10-11 o'clock position in the second. Less likely in the second because the nitrile/silicone adbv might maintain enough of a seal between inlet dirty oil and outlet clean side by covering the endcap gap shown.
That said, with tight uniform pleating and the pressure from the compression/leaf spring could possibly keep those areas covered during the fci as the indention marks indicate. Still imo, it's preferable to see the ends of the centertube completely covered at least in post use dissections.
Otoh, the pics from this thread show what can happen with something less than tight uniform pleating and fiber endcaps, TG in this case. Oil bypass area clearly visible. In the first the gap area is in bypass. The second and third shows how the previously mentioned pleat deformation can uncover the seal area of centertube end and endcap in the area of the pleat deformation. In this case though the more severe and obvious bypass area is the gap shown in first pic. And it's not caused by 'glazed oil' at
Sayjac, this is a great example. That extra wide pleat space is a killer. Once delta P bends the pleats over and pulls the end caps in, the filter goes into bypass. What is somewhat concerning is the filter should have capacity for 10,000 miles. The anecdote was less than 5,000 miles using 5W30.
Good thread and good discussion!
Using the newest pics posted above, 'if' they were to represent the condition of the filter and placement of the endcaps at some point 'during the oci', then oil would be bypassing unfiltered oil at the 12 o'clock in first pic, and 10-11 o'clock position in the second. Less likely in the second because the nitrile/silicone adbv might maintain enough of a seal between inlet dirty oil and outlet clean side by covering the endcap gap shown.
That said, with tight uniform pleating and the pressure from the compression/leaf spring could possibly keep those areas covered during the fci as the indention marks indicate. Still imo, it's preferable to see the ends of the centertube completely covered at least in post use dissections.
Otoh, the pics from this thread show what can happen with something less than tight uniform pleating and fiber endcaps, TG in this case. Oil bypass area clearly visible. In the first the gap area is in bypass. The second and third shows how the previously mentioned pleat deformation can uncover the seal area of centertube end and endcap in the area of the pleat deformation. In this case though the more severe and obvious bypass area is the gap shown in first pic. And it's not caused by 'glazed oil' at
Sayjac, this is a great example. That extra wide pleat space is a killer. Once delta P bends the pleats over and pulls the end caps in, the filter goes into bypass. What is somewhat concerning is the filter should have capacity for 10,000 miles. The anecdote was less than 5,000 miles using 5W30.
Good thread and good discussion!
Any non-wire backed filter with wide pleat spacing is asking for problems of some type, regardless of brand - it's a common denominator.
Write on the blackboard 100 times:
Wide pleat spacing with along with delta-p is bad.
Wide pleat spacing with along with delta-p is bad.
Wide pleat spacing with along with delta-p is bad.
etc
etc
.
.
.
Write on the blackboard 100 times:
Wide pleat spacing with along with delta-p is bad.
Wide pleat spacing with along with delta-p is bad.
Wide pleat spacing with along with delta-p is bad.
etc
etc
.
.
.
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- Dec 30, 2006
- Messages
- 29,558
I've used Frams forever,but they just look so sloppy. The thin cans and the sloppily cut looking center tube holes. I've moved on to Wix because I like the sturdier and more precision construction.
Originally Posted By: DuckRyder
Originally Posted By: Sayjac
Using the newest pics posted above, 'if' they were to represent the condition of the filter and placement of the endcaps at some point 'during the oci', then oil would be bypassing unfiltered oil at the 12 o'clock in first pic, and 10-11 o'clock position in the second. Less likely in the second because the nitrile/silicone adbv might maintain enough of a seal between inlet dirty oil and outlet clean side by covering the endcap gap shown.
That said, with tight uniform pleating and the pressure from the compression/leaf spring could possibly keep those areas covered during the fci as the indention marks indicate. Still imo, it’s preferable to see the ends of the center tube completely covered at least in post use dissections.
…..I don’t believe that filter element is in bypass even IF that is the way it was when assembled (which it wasn’t because of the leaf/bypass)…
If the center tube 'ends' were exposed/uncovered (media also visible as pictured) at any point during the oci, then dirty side oil is bypassing the media at those points as noted on the clock orientation. The central/inner part of the endcap is designed to cover those areas entirely allowing oil to pass only through the media. Not around it as would be the case in the exposed areas.
Quote:
The media is bonded to each end cap - Right?
If the media is bonded to the end caps the only way from the dirty to the clean side either through the media or around the end cap - Right?
The latter part (or around the end cap) is the key point being shown with the exposed center tube ends. Dirty oil is not passing through the media first at those points. Going unfiltered to outlet, at least at those points.
Quote:
So, if the leaf spring / bypass assembly and ADBV are sealed to the end caps, the only way from the clean to dirty side is through the media - Right?
And those points remain "sealed" only if the central/(inner) part of the endcaps cover the center tube ends the entire circumference at those areas, ie., the leaf spring bypass and adbv.
Quote:
If the media and end caps were completely rigid (I know they are not) THEN the center tube would be unnecessary. Right?
As long as the dirty side oil can only pass through the media before outlet that would be true. But not how the Fram fiber design is made.
Quote:
So my contention is that the end caps are the sealing surface, not the center tube. The center tube provides support for the media, but it doesn’t alter the path through the media...
As noted, in the Fram design if the center tube 'ends' are not covered by the fiber endcaps the entire circumference, then dirty side oil is bypassing the media at those points.
Originally Posted By: Sayjac
Otoh, the pics from this thread show what can happen with something less than tight uniform pleating and fiber endcaps, TG in this case. Oil bypass area clearly visible. In the first the gap area is in bypass. The second and third shows how the previously mentioned pleat deformation can uncover the seal area of centertube end and endcap in the area of the pleat deformation. In this case though the more severe and obvious bypass area is the gap shown in first pic. And it's not caused by 'glazed oil' at
Quote:
That one is a problem... but it wasn’t in bypass until the end cap pulled away from the ADBV or leaf spring (it actually looks like it pulled away from both in some of the thread photos).
It was in bypass whenever the pleat distortion pulled enough at the fiber endcap to cause it distort and open the space, and uncover the center tube end(s) adjacent to those areas. As noted the more serious bypass in this case is the obvious open space shown in pic one. Whenever that was, same result as a pleat tear.
Originally Posted By: WellOiled
...Sayjac, this is a great example. That extra wide pleat space is a killer. Once delta P bends the pleats over and pulls the end caps in, the filter goes into bypass. What is somewhat concerning is the filter should have capacity for 10,000 miles. The anecdote was less than 5,000 miles using 5W30.
...
Agreed. It would seem a 10k rated filter should be able to handle a fci without much difficulty.
Originally Posted By: Sayjac
Using the newest pics posted above, 'if' they were to represent the condition of the filter and placement of the endcaps at some point 'during the oci', then oil would be bypassing unfiltered oil at the 12 o'clock in first pic, and 10-11 o'clock position in the second. Less likely in the second because the nitrile/silicone adbv might maintain enough of a seal between inlet dirty oil and outlet clean side by covering the endcap gap shown.
That said, with tight uniform pleating and the pressure from the compression/leaf spring could possibly keep those areas covered during the fci as the indention marks indicate. Still imo, it’s preferable to see the ends of the center tube completely covered at least in post use dissections.
…..I don’t believe that filter element is in bypass even IF that is the way it was when assembled (which it wasn’t because of the leaf/bypass)…
If the center tube 'ends' were exposed/uncovered (media also visible as pictured) at any point during the oci, then dirty side oil is bypassing the media at those points as noted on the clock orientation. The central/inner part of the endcap is designed to cover those areas entirely allowing oil to pass only through the media. Not around it as would be the case in the exposed areas.
Quote:
The media is bonded to each end cap - Right?
If the media is bonded to the end caps the only way from the dirty to the clean side either through the media or around the end cap - Right?
The latter part (or around the end cap) is the key point being shown with the exposed center tube ends. Dirty oil is not passing through the media first at those points. Going unfiltered to outlet, at least at those points.
Quote:
So, if the leaf spring / bypass assembly and ADBV are sealed to the end caps, the only way from the clean to dirty side is through the media - Right?
And those points remain "sealed" only if the central/(inner) part of the endcaps cover the center tube ends the entire circumference at those areas, ie., the leaf spring bypass and adbv.
Quote:
If the media and end caps were completely rigid (I know they are not) THEN the center tube would be unnecessary. Right?
As long as the dirty side oil can only pass through the media before outlet that would be true. But not how the Fram fiber design is made.
Quote:
So my contention is that the end caps are the sealing surface, not the center tube. The center tube provides support for the media, but it doesn’t alter the path through the media...
As noted, in the Fram design if the center tube 'ends' are not covered by the fiber endcaps the entire circumference, then dirty side oil is bypassing the media at those points.
Originally Posted By: Sayjac
Otoh, the pics from this thread show what can happen with something less than tight uniform pleating and fiber endcaps, TG in this case. Oil bypass area clearly visible. In the first the gap area is in bypass. The second and third shows how the previously mentioned pleat deformation can uncover the seal area of centertube end and endcap in the area of the pleat deformation. In this case though the more severe and obvious bypass area is the gap shown in first pic. And it's not caused by 'glazed oil' at
Quote:
That one is a problem... but it wasn’t in bypass until the end cap pulled away from the ADBV or leaf spring (it actually looks like it pulled away from both in some of the thread photos).
It was in bypass whenever the pleat distortion pulled enough at the fiber endcap to cause it distort and open the space, and uncover the center tube end(s) adjacent to those areas. As noted the more serious bypass in this case is the obvious open space shown in pic one. Whenever that was, same result as a pleat tear.
Originally Posted By: WellOiled
...Sayjac, this is a great example. That extra wide pleat space is a killer. Once delta P bends the pleats over and pulls the end caps in, the filter goes into bypass. What is somewhat concerning is the filter should have capacity for 10,000 miles. The anecdote was less than 5,000 miles using 5W30.
Agreed. It would seem a 10k rated filter should be able to handle a fci without much difficulty.
Originally Posted By: Sayjac
As noted, in the Fram design if the center tube 'ends' are not covered by the fiber endcaps the entire circumference, then dirty side oil is bypassing the media at those points.
Originally Posted By: DuckRyder
Even though the end of the center tube is off center slightly and exposed on that example, it's evident that there was still a good sealing ring impression in the end cap, and therefore there shouldn't have been any dirty oil leakage/bypass.
If you took the center tube out and the seal on the end cap still sealed as evident by the impression, there still wouldn't be any dirty oil bypassing. Covering the end of the center tube or not has nothing to do with sealing the end cap.
As noted, in the Fram design if the center tube 'ends' are not covered by the fiber endcaps the entire circumference, then dirty side oil is bypassing the media at those points.
Originally Posted By: DuckRyder
Even though the end of the center tube is off center slightly and exposed on that example, it's evident that there was still a good sealing ring impression in the end cap, and therefore there shouldn't have been any dirty oil leakage/bypass.
If you took the center tube out and the seal on the end cap still sealed as evident by the impression, there still wouldn't be any dirty oil bypassing. Covering the end of the center tube or not has nothing to do with sealing the end cap.
Quote:
... Even though the end of the center tube is off center slightly and exposed on that example, it's evident that there was still a good sealing ring impression in the end cap, and therefore there shouldn't have been any dirty oil leakage/bypass.
If you took the center tube out and the seal on the end cap still sealed as evident by the impression, there still wouldn't be any dirty oil bypassing. Covering the end of the center tube or not has nothing to do with sealing the end cap.
Those two statements are contradictory. The first is saying that having a "good sealing ring impression in the end cap" 'could/should' indicate prevention of dirty oil bypass in the uncovered/exposed area at 12 o'clock. That sealing ring is formed by the pressure from the leaf spring/bypass on the endcap from the center tube end, covering it and forming the seal so no bypass of dirty oil. In other words, no bypass in the space between the inner/central media area and the center tube.
The second says covering the end of the center tube or not has nothing to do with sealing at the endcap even if the impression formed is made by the center tube ends on one side covering the center tube. If covering the centertube end doesn't matter, then the first statement is a moot point.
So it's either the seal maintained as indicated by the impressions noted in the first statement, or covering the end of the Fram fiber OF center tube has nothing to do with the maintaining the seal as indicated by the impressions on the endcap(s). In this case, former that's true, not the latter.
... Even though the end of the center tube is off center slightly and exposed on that example, it's evident that there was still a good sealing ring impression in the end cap, and therefore there shouldn't have been any dirty oil leakage/bypass.
If you took the center tube out and the seal on the end cap still sealed as evident by the impression, there still wouldn't be any dirty oil bypassing. Covering the end of the center tube or not has nothing to do with sealing the end cap.
Those two statements are contradictory. The first is saying that having a "good sealing ring impression in the end cap" 'could/should' indicate prevention of dirty oil bypass in the uncovered/exposed area at 12 o'clock. That sealing ring is formed by the pressure from the leaf spring/bypass on the endcap from the center tube end, covering it and forming the seal so no bypass of dirty oil. In other words, no bypass in the space between the inner/central media area and the center tube.
The second says covering the end of the center tube or not has nothing to do with sealing at the endcap even if the impression formed is made by the center tube ends on one side covering the center tube. If covering the centertube end doesn't matter, then the first statement is a moot point.
So it's either the seal maintained as indicated by the impressions noted in the first statement, or covering the end of the Fram fiber OF center tube has nothing to do with the maintaining the seal as indicated by the impressions on the endcap(s). In this case, former that's true, not the latter.
The two paragraphs are saying the same thing (the 2nd paragraph a more extreme example), that the center tube alignment to the hole in the end cap has no affect on the sealing, as evidenced by the complete 360 degree seal impression in the end cap.
The only way the center tube could affect the seal on the end cap is if it prevented the leaf spring or ADBV from making a complete 360 deg seal (the impression ring). I see no evidence of that happening in this example.
The only way the center tube could affect the seal on the end cap is if it prevented the leaf spring or ADBV from making a complete 360 deg seal (the impression ring). I see no evidence of that happening in this example.
Y’all are going to make me cut an end cap off of one of these aren’t you. To be frank I’m a little baffled by the contention that this gap allows bypass. It seems quite obvious to me and I have a high degree of certainty I’m not missing anything.
So here is my related question: Why do you think this is a bypass but the holes punched in the center tube are not? Draw me pictures if required.
So here is my related question: Why do you think this is a bypass but the holes punched in the center tube are not? Draw me pictures if required.
Originally Posted By: DuckRyder
Y’all are going to make me cut an end cap off of one of these aren’t you. To be frank I’m a little baffled by the contention that this gap allows bypass.....
Perhaps think of it this way, if that gap was open as pictured at 12 o'clock during an oci, would dirty/unfiltered oil be reaching and passing though that opening or would it be filtered oil? If you think about it you should come to the conclusion that it is dirty side oil, in bypass. Has that oil passed though the media first? No, not if it went through the opening.
Quote:
So here is my related question: Why do you think this is a bypass but the holes punched in the center tube are not? Draw me pictures if required.
Assuming the media is the only path (except in rare bypass event) for dirty inlet side oil to pass through (which it should be), the holes or louvers are only allowing filtered oil to pass to the outlet side, central portion of the filter.
If you can't visualize it, have to save a drawing or pic till later.
Y’all are going to make me cut an end cap off of one of these aren’t you. To be frank I’m a little baffled by the contention that this gap allows bypass.....
Perhaps think of it this way, if that gap was open as pictured at 12 o'clock during an oci, would dirty/unfiltered oil be reaching and passing though that opening or would it be filtered oil? If you think about it you should come to the conclusion that it is dirty side oil, in bypass. Has that oil passed though the media first? No, not if it went through the opening.
Quote:
So here is my related question: Why do you think this is a bypass but the holes punched in the center tube are not? Draw me pictures if required.
Assuming the media is the only path (except in rare bypass event) for dirty inlet side oil to pass through (which it should be), the holes or louvers are only allowing filtered oil to pass to the outlet side, central portion of the filter.
If you can't visualize it, have to save a drawing or pic till later.
Originally Posted By: Sayjac
Originally Posted By: DuckRyder
Y’all are going to make me cut an end cap off of one of these aren’t you. To be frank I’m a little baffled by the contention that this gap allows bypass.....
Perhaps think of it this way, if that gap was open as pictured at 12 o'clock during an oci, would dirty/unfiltered oil be reaching and passing though that opening or would it be filtered oil? If you think about it you should come to the conclusion that it is dirty side oil, in bypass. Has that oil passed though the media first? No, if it went through the opening.
It is exactly the same oil as is every where else in the center of the media so no it isn’t in bypass.
Let us look at the media/end cap assembly - the media is glued to the end caps, the end caps completely cover the ends of the pleats. once you seal the center holes in the end caps (which is what the ADBV and leaf do) the flow of oil is fixed. Oil cannot pass from dirty to clean side any way but by being filtered through the media. The center tube is irrelevant to the path of the oil from dirty to clean...
Originally Posted By: Sayjac
Quote:
So here is my related question: Why do you think this is a bypass but the holes punched in the center tube are not? Draw me pictures if required.
Assuming the media is the only path (except in rare bypass event) for dirty inlet side oil to pass through (which it should be), the holes or louvers are only allowing filtered oil to pass to the outlet side, central portion of the filter.
If you can't visualize it, have to save a drawing or pic till later.
The media is not bonded to the center tube, keep thinking about “the media being the only path (except in a rare bypass event)" and I think you will have it, if not explain how it is that the center tube changes that path.
Originally Posted By: DuckRyder
Y’all are going to make me cut an end cap off of one of these aren’t you. To be frank I’m a little baffled by the contention that this gap allows bypass.....
Perhaps think of it this way, if that gap was open as pictured at 12 o'clock during an oci, would dirty/unfiltered oil be reaching and passing though that opening or would it be filtered oil? If you think about it you should come to the conclusion that it is dirty side oil, in bypass. Has that oil passed though the media first? No, if it went through the opening.
It is exactly the same oil as is every where else in the center of the media so no it isn’t in bypass.
Let us look at the media/end cap assembly - the media is glued to the end caps, the end caps completely cover the ends of the pleats. once you seal the center holes in the end caps (which is what the ADBV and leaf do) the flow of oil is fixed. Oil cannot pass from dirty to clean side any way but by being filtered through the media. The center tube is irrelevant to the path of the oil from dirty to clean...
Originally Posted By: Sayjac
Quote:
So here is my related question: Why do you think this is a bypass but the holes punched in the center tube are not? Draw me pictures if required.
Assuming the media is the only path (except in rare bypass event) for dirty inlet side oil to pass through (which it should be), the holes or louvers are only allowing filtered oil to pass to the outlet side, central portion of the filter.
If you can't visualize it, have to save a drawing or pic till later.
The media is not bonded to the center tube, keep thinking about “the media being the only path (except in a rare bypass event)" and I think you will have it, if not explain how it is that the center tube changes that path.
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IMO in a fiber end cap filter like this, seeing an impression on the gasket felt is misleading. When this filter is used the hot oil and pressure may affect the media and the poorly supported seal may be too weak to prevent bypass. Media on this filter is not very rigid or a spring. It's a defect to see a short center tube. Certainly a 1/4" gap above the center tube would be an issue here. It would be put filter in the trash time on that. Of course I remember my grandfather eating around the worm in the apple, but that's because he didn't buy it but picked it. If we see a worm in an apple we don't buy it.
Originally Posted By: DuckRyder
Originally Posted By: Sayjac
Originally Posted By: DuckRyder
Y’all are going to make me cut an end cap off of one of these aren’t you. To be frank I’m a little baffled by the contention that this gap allows bypass.....
Perhaps think of it this way, if that gap was open as pictured at 12 o'clock during an oci, would dirty/unfiltered oil be reaching and passing though that opening or would it be filtered oil? If you think about it you should come to the conclusion that it is dirty side oil, in bypass. Has that oil passed though the media first? No, if it went through the opening.
It is exactly the same oil as is every where else in the center of the media so no it isn’t in bypass.
So your conclusion is that, assuming that 12 o'clock opening is present even during an oci it is 'not' directly exposed to the dirty side of the filter. Have to agree to disagree. If that opening would be there during an oci, dirty oil would be bypassing through that opening and not through the media first, at that point. Further you are saying the opening is designed to be that way? No, not possible in this design.
Quote:
….the media is glued to the end caps, the end caps completely cover the ends of the pleats.
That is a true statement. However, that has no effect on the opening at 12 o'clock which is central to, inside the clean side of the pleats.
Quote:
The media is not bonded to the center tube
Also a true statement but again has no effect if there is an opening present and exposed to the dirty side of the filter.
Quote:
if not explain how it is that the center tube changes that path.
I never said or posited that the tube itself changes the path. I noted the seal areas of the endcaps on the centertube ends.
On fiber endcap filters like Fram, the endcaps perform the same basic function as metal end cap filters do in their construction. If I was to drill a hole (an opening) down through a metal endcap, at a point exactly between the clean side of the media (inner/central, not touching the media) and the centertube, oil would be in bypass. The opening shown would be doing the same thing. That's assuming it was like that during the oci.
Besides the member in this thread that has pointed it out with some regularity, fwiw, another member edhackett has noted the same phenomenon a few times in some previous fiber endcaps dissections. Linked is one such thread. Noted is your comment about witness marks showing a seal on the endcap is present, at least at some point during the oci.
https://www.bobistheoilguy.com/forums/ub...rd_#Post3787334
Really though, if you can't see how the opening would be exposed to the filter's dirty side, then unlikely to see how the filter is in bypass in that event. And, not every anecdote will show this situation post use. Some exhibit fully covered tubes all the way around.
Originally Posted By: Sayjac
Originally Posted By: DuckRyder
Y’all are going to make me cut an end cap off of one of these aren’t you. To be frank I’m a little baffled by the contention that this gap allows bypass.....
Perhaps think of it this way, if that gap was open as pictured at 12 o'clock during an oci, would dirty/unfiltered oil be reaching and passing though that opening or would it be filtered oil? If you think about it you should come to the conclusion that it is dirty side oil, in bypass. Has that oil passed though the media first? No, if it went through the opening.
It is exactly the same oil as is every where else in the center of the media so no it isn’t in bypass.
So your conclusion is that, assuming that 12 o'clock opening is present even during an oci it is 'not' directly exposed to the dirty side of the filter. Have to agree to disagree. If that opening would be there during an oci, dirty oil would be bypassing through that opening and not through the media first, at that point. Further you are saying the opening is designed to be that way? No, not possible in this design.
Quote:
….the media is glued to the end caps, the end caps completely cover the ends of the pleats.
That is a true statement. However, that has no effect on the opening at 12 o'clock which is central to, inside the clean side of the pleats.
Quote:
The media is not bonded to the center tube
Also a true statement but again has no effect if there is an opening present and exposed to the dirty side of the filter.
Quote:
if not explain how it is that the center tube changes that path.
I never said or posited that the tube itself changes the path. I noted the seal areas of the endcaps on the centertube ends.
On fiber endcap filters like Fram, the endcaps perform the same basic function as metal end cap filters do in their construction. If I was to drill a hole (an opening) down through a metal endcap, at a point exactly between the clean side of the media (inner/central, not touching the media) and the centertube, oil would be in bypass. The opening shown would be doing the same thing. That's assuming it was like that during the oci.
Besides the member in this thread that has pointed it out with some regularity, fwiw, another member edhackett has noted the same phenomenon a few times in some previous fiber endcaps dissections. Linked is one such thread. Noted is your comment about witness marks showing a seal on the endcap is present, at least at some point during the oci.
https://www.bobistheoilguy.com/forums/ub...rd_#Post3787334
Really though, if you can't see how the opening would be exposed to the filter's dirty side, then unlikely to see how the filter is in bypass in that event. And, not every anecdote will show this situation post use. Some exhibit fully covered tubes all the way around.
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