anti drainback valve question
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Originally Posted By: ZeeOSix
Originally Posted By: dickwells
After multiple explanations, there seems to be an unending supply of people who do not understand the function of the adbv in a filter mounted threads up, or sideways.
You must mean "threads down".
No, I mean exactly what I say, we all agree that oil will not drain out of a filter mounted threads up, however oil from the galleries will drain through it and back to the pan, leaving them empty.
Originally Posted By: dickwells
After multiple explanations, there seems to be an unending supply of people who do not understand the function of the adbv in a filter mounted threads up, or sideways.
You must mean "threads down".
No, I mean exactly what I say, we all agree that oil will not drain out of a filter mounted threads up, however oil from the galleries will drain through it and back to the pan, leaving them empty.
Originally Posted By: dickwells
No, I mean exactly what I say, we all agree that oil will not drain out of a filter mounted threads up, however oil from the galleries will drain through it and back to the pan, leaving them empty.
Given a reasonable amount of time, that's going to happen anyway. The same applies to an thread side down or horizontal oil filter, ADBV or not.
The only way to guarantee that the oil filter is full of oil and doesn't have to be refilled by the oil pump is to have it mounted thread side up. If our goal is to have the lubrication system fully primed every time before we start it, we had better start looking at a pre-lube setup rather than worry about ADBVs, because a little piece of silicone or nitrile isn't going to do it over the long term.
I've had taxis go 600,000 miles without them ever seeing an ADBV. I like them because they make the engine sound prettier at startup - nothing more, nothing less.
No, I mean exactly what I say, we all agree that oil will not drain out of a filter mounted threads up, however oil from the galleries will drain through it and back to the pan, leaving them empty.
Given a reasonable amount of time, that's going to happen anyway. The same applies to an thread side down or horizontal oil filter, ADBV or not.
The only way to guarantee that the oil filter is full of oil and doesn't have to be refilled by the oil pump is to have it mounted thread side up. If our goal is to have the lubrication system fully primed every time before we start it, we had better start looking at a pre-lube setup rather than worry about ADBVs, because a little piece of silicone or nitrile isn't going to do it over the long term.
I've had taxis go 600,000 miles without them ever seeing an ADBV. I like them because they make the engine sound prettier at startup - nothing more, nothing less.
From someone who sold filters..
I am no engineer when it comes to this but I will tell you what I have been told by the engineer at Wix that I know. The anti drain back valve is important on certain engines no matter how the filter is mounted. On our GM engines and others with the filter mounted upright, it allows oil to remain in some of the passages where it would otherwise drain back.
Again, I asked this same question and was told that if it is desiged in from the OE, it is vital that it be there.
I am no engineer when it comes to this but I will tell you what I have been told by the engineer at Wix that I know. The anti drain back valve is important on certain engines no matter how the filter is mounted. On our GM engines and others with the filter mounted upright, it allows oil to remain in some of the passages where it would otherwise drain back.
Again, I asked this same question and was told that if it is desiged in from the OE, it is vital that it be there.
Originally Posted By: edwardh1
what does it do?
- keep oil in the engine?
or
- keep the filter full
what is the oil flow path?
oil pump - filter - engine parts - then drain to pan?
The ADBV serves a couple of purposes.
First of all, It keeps the oil in the upper galleys from darining back through the filter when the engine is off. This minimizes the amount of time needed to bring the oil to full pressure on startup. This is also important on GM engine designs that use hydraulic lifters, which also minimizes the amount of valve train clatter after startup.
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. This function is important on horizontal and vertical mounts but probably more on horizontal.
what does it do?
- keep oil in the engine?
or
- keep the filter full
what is the oil flow path?
oil pump - filter - engine parts - then drain to pan?
The ADBV serves a couple of purposes.
First of all, It keeps the oil in the upper galleys from darining back through the filter when the engine is off. This minimizes the amount of time needed to bring the oil to full pressure on startup. This is also important on GM engine designs that use hydraulic lifters, which also minimizes the amount of valve train clatter after startup.
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. This function is important on horizontal and vertical mounts but probably more on horizontal.
Originally Posted By: brights_garage
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. This function is important on horizontal and vertical mounts but probably more on horizontal.
Why would it be more important on horizontal filters than vertical filters?
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. This function is important on horizontal and vertical mounts but probably more on horizontal.
Why would it be more important on horizontal filters than vertical filters?
Originally Posted By: brights_garage
First of all, It keeps the oil in the upper galleys from darining back through the filter when the engine is off. This minimizes the amount of time needed to bring the oil to full pressure on startup. This is also important on GM engine designs that use hydraulic lifters, which also minimizes the amount of valve train clatter after startup.
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. This function is important on horizontal and vertical mounts but probably more on horizontal.
I'd be skeptical as to how long the ADBV is capable of holding oils in the galleries. Their performance in keeping the filter full is limited enough as it is. Startup noise, in my opinion, is more of a cosmetic issue rather than one related to long term engine life.
I'd say it's much more of an issue with a horizontal filter, as you pointed out. With respect to oil draining back into the pan and taking contaminants with it, what's the big deal, really? The oil is going to be filtered again right away, assuming it doesn't go into bypass mode.
First of all, It keeps the oil in the upper galleys from darining back through the filter when the engine is off. This minimizes the amount of time needed to bring the oil to full pressure on startup. This is also important on GM engine designs that use hydraulic lifters, which also minimizes the amount of valve train clatter after startup.
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. This function is important on horizontal and vertical mounts but probably more on horizontal.
I'd be skeptical as to how long the ADBV is capable of holding oils in the galleries. Their performance in keeping the filter full is limited enough as it is. Startup noise, in my opinion, is more of a cosmetic issue rather than one related to long term engine life.
I'd say it's much more of an issue with a horizontal filter, as you pointed out. With respect to oil draining back into the pan and taking contaminants with it, what's the big deal, really? The oil is going to be filtered again right away, assuming it doesn't go into bypass mode.
Originally Posted By: ZeeOSix
Why would it be more important on horizontal filters than vertical filters?
Sideways (or dome side up) filters without an ADBV would (assuming they're not the lowest point of the oil circuit) be susceptible to having their oil flow out to the lowest point in the circuit.
Why would it be more important on horizontal filters than vertical filters?
Sideways (or dome side up) filters without an ADBV would (assuming they're not the lowest point of the oil circuit) be susceptible to having their oil flow out to the lowest point in the circuit.
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Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. .
Contaminate it with the identical oil in the pan where it came from? The first published utterance of this in a filter study should have got the anal retentive OCD author invites for therapy. It's not well thought out at all ..or at least expressed in a manner that has any indication of a sensible logic train.
The unfiltered oil is identical with the oil in the pan. Exactly where it came from. Oil is immeasurably identical from one pass to the next outside of a certification/validation lab. For all intents and purposes ....it's the same.
This is NOT a liability to any way. NOW IF the flow were to "back wash" the media, ..then COLLECTED CONTAMINANTS could feasibly get released en mass and present unfavorable results.
The ADBV is to assure that this is a slow process in engines where filter orientation (typically in elevation as much as vert/horiz ) would require it. Some do not.
There are a limited number of filters that have checks at inlet and outlet. They're in very limited distribution and only recommended for a few applications.
Sorry, that filter study really annoyed the heck out of me. I do ..beg your pardon.
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. .
Contaminate it with the identical oil in the pan where it came from? The first published utterance of this in a filter study should have got the anal retentive OCD author invites for therapy. It's not well thought out at all ..or at least expressed in a manner that has any indication of a sensible logic train.
The unfiltered oil is identical with the oil in the pan. Exactly where it came from. Oil is immeasurably identical from one pass to the next outside of a certification/validation lab. For all intents and purposes ....it's the same.
This is NOT a liability to any way. NOW IF the flow were to "back wash" the media, ..then COLLECTED CONTAMINANTS could feasibly get released en mass and present unfavorable results.
The ADBV is to assure that this is a slow process in engines where filter orientation (typically in elevation as much as vert/horiz ) would require it. Some do not.
There are a limited number of filters that have checks at inlet and outlet. They're in very limited distribution and only recommended for a few applications.
Sorry, that filter study really annoyed the heck out of me. I do ..beg your pardon.
Originally Posted By: ZeeOSix
Originally Posted By: brights_garage
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. This function is important on horizontal and vertical mounts but probably more on horizontal.
Why would it be more important on horizontal filters than vertical filters?
Hi Zee. The theory here is that most of the vertical filters are mounted threads up and usually below the block. Even if the oil galleys drained back through the filter (However slow that is), The filter would still be full of oil. On a horizontal design however, not only can the oil galleys drain but some if not all of the oil in the filter as well. Again in theory the oil could drain down to the level of the inlet hole on the block.
Originally Posted By: brights_garage
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. This function is important on horizontal and vertical mounts but probably more on horizontal.
Why would it be more important on horizontal filters than vertical filters?
Hi Zee. The theory here is that most of the vertical filters are mounted threads up and usually below the block. Even if the oil galleys drained back through the filter (However slow that is), The filter would still be full of oil. On a horizontal design however, not only can the oil galleys drain but some if not all of the oil in the filter as well. Again in theory the oil could drain down to the level of the inlet hole on the block.
Originally Posted By: Gary Allan
Quote:
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. .
NOW IF the flow were to "back wash" the media, ..then COLLECTED CONTAMINANTS could feasibly get released en mass and present unfavorable results.
The ADBV is to assure that this is a slow process in engines where filter orientation (typically in elevation as much as vert/horiz ) would require it. Some do not.
There are a limited number of filters that have checks at inlet and outlet. They're in very limited distribution and only recommended for a few applications.
Hi Gary. Very well said. It is the "collected contaminants" I am speaking of. Thanks
Quote:
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. .
NOW IF the flow were to "back wash" the media, ..then COLLECTED CONTAMINANTS could feasibly get released en mass and present unfavorable results.
The ADBV is to assure that this is a slow process in engines where filter orientation (typically in elevation as much as vert/horiz ) would require it. Some do not.
There are a limited number of filters that have checks at inlet and outlet. They're in very limited distribution and only recommended for a few applications.
Hi Gary. Very well said. It is the "collected contaminants" I am speaking of. Thanks
Originally Posted By: brights_garage
Originally Posted By: ZeeOSix
Originally Posted By: brights_garage
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. This function is important on horizontal and vertical mounts but probably more on horizontal.
Why would it be more important on horizontal filters than vertical filters?
Hi Zee. The theory here is that most of the vertical filters are mounted threads up and usually below the block.
When I was reading "vertical" in the posts I was assuming base down orientation, not base up like on a GM small block. I'd say a filter mounted vertical with base down taxes the ADBV about as much as you could.
Originally Posted By: ZeeOSix
Originally Posted By: brights_garage
Second, It keeps the oil on the unfiltered side of the filter from daraining back to the pan taking the contaminants with it. This function is important on horizontal and vertical mounts but probably more on horizontal.
Why would it be more important on horizontal filters than vertical filters?
Hi Zee. The theory here is that most of the vertical filters are mounted threads up and usually below the block.
When I was reading "vertical" in the posts I was assuming base down orientation, not base up like on a GM small block. I'd say a filter mounted vertical with base down taxes the ADBV about as much as you could.
Originally Posted By: Gary Allan
NOW IF the flow were to "back wash" the media, ..then COLLECTED CONTAMINANTS could feasibly get released en mass and present unfavorable results.
The ADBV is to assure that this is a slow process in engines where filter orientation (typically in elevation as much as vert/horiz ) would require it. Some do not.
Gary, so what happens then? Do the large number of backwashed particles clog the oil pump, pick up line, or filter? Does the oil pressure at startup trigger the oil filter bypass or force part of the backwashed particles to pass unfiltered through the media? Or is it simply bad policy to free particles that were already trapped by the oil filter?
NOW IF the flow were to "back wash" the media, ..then COLLECTED CONTAMINANTS could feasibly get released en mass and present unfavorable results.
The ADBV is to assure that this is a slow process in engines where filter orientation (typically in elevation as much as vert/horiz ) would require it. Some do not.
Gary, so what happens then? Do the large number of backwashed particles clog the oil pump, pick up line, or filter? Does the oil pressure at startup trigger the oil filter bypass or force part of the backwashed particles to pass unfiltered through the media? Or is it simply bad policy to free particles that were already trapped by the oil filter?
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Gary, so what happens then?
If you're lucky it falls out in a silt and stays put in the bottom or side of the filter. The same if those particles made it back to the pan.
Quote:
Does the oil pressure at startup trigger the oil filter bypass or force part of the backwashed particles to pass unfiltered through the media?
This is one potential issue. While I don't worry about a threaded end bypass much ..it's only because I don't worry too much about backwashed media depositing silt in the filter anyway. Out of all the filters cut open here, I can't recall too many beyond my own (VSOT sinking out) where they were perhaps horizontally oriented, having an silt in them. None in fact. About the only thing to leave a show in the filter were magnets ..for obvious reasons.
Quote:
Or is it simply bad policy to free particles that were already trapped by the oil filter?
I wouldn't want a mass of particles of unknown size infused into my oil stream. During the course of a filter's life span it mostly collects combustion byproducts. There's the occasional piece of the engine that gets thrown off. It may be 35um ..65um ...100+um. They're not necessarily rare, but aren't part of the normal wearing process (note "normal"). It's just a random thing that's not uncommon. Things decay. The world is an imperfect place. Now you can have a really abrasive situation that, if repeated enough, could result in some impact.
Gary, so what happens then?
If you're lucky it falls out in a silt and stays put in the bottom or side of the filter. The same if those particles made it back to the pan.
Quote:
Does the oil pressure at startup trigger the oil filter bypass or force part of the backwashed particles to pass unfiltered through the media?
This is one potential issue. While I don't worry about a threaded end bypass much ..it's only because I don't worry too much about backwashed media depositing silt in the filter anyway. Out of all the filters cut open here, I can't recall too many beyond my own (VSOT sinking out) where they were perhaps horizontally oriented, having an silt in them. None in fact. About the only thing to leave a show in the filter were magnets ..for obvious reasons.
Quote:
Or is it simply bad policy to free particles that were already trapped by the oil filter?
I wouldn't want a mass of particles of unknown size infused into my oil stream. During the course of a filter's life span it mostly collects combustion byproducts. There's the occasional piece of the engine that gets thrown off. It may be 35um ..65um ...100+um. They're not necessarily rare, but aren't part of the normal wearing process (note "normal"). It's just a random thing that's not uncommon. Things decay. The world is an imperfect place. Now you can have a really abrasive situation that, if repeated enough, could result in some impact.
Thanks for the detailed answer. Ha, it sounds somewhat like hitting a wasp nest with a stick. It might not cause a single problem if the nest is abandoned, but it could generate many problems if the nest is active. Why risk potential issues by permitting rapid backflow?
Originally Posted By: brights_garage
The theory here is that most of the vertical filters are mounted threads up and usually below the block. Even if the oil galleys drained back through the filter (However slow that is), The filter would still be full of oil.
I would agree with that. Most of the thread side up filters I've deal with have been fairly low on the engine. Certainly, any siphoning effect is slowed if the filter is rather low, or, for that matter, rather high.
As was indicated, I don't think washing of the media is a huge concern. A few millilitres of oil that could potentially wash back is neither a lot of volume nor a lot of flow.
The theory here is that most of the vertical filters are mounted threads up and usually below the block. Even if the oil galleys drained back through the filter (However slow that is), The filter would still be full of oil.
I would agree with that. Most of the thread side up filters I've deal with have been fairly low on the engine. Certainly, any siphoning effect is slowed if the filter is rather low, or, for that matter, rather high.
As was indicated, I don't think washing of the media is a huge concern. A few millilitres of oil that could potentially wash back is neither a lot of volume nor a lot of flow.
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Believe as you please. Pete C. from WIX has confirmed this many times. It's supported by the simple fact that IF it was ONLY there to keep the oil filter full ...EVERY nitrile ADBV would be a BUZZKILL FAIL.
That's not to say that some engine manufactures aren't using them to keep filters full. But it's a convenient co-product of the primary function of the thing.
If you don't hear start up rattle with a nitrile ADBV filter ..your engine has a lubrication system configuration that doesn't allow the filter to empty one way or another.
IF keeping the filter full ...with the specifying of a silicon ADBV was a requirement, then the "meets or exceeds" claim by EVERY filter man would be a bold faced lie. If it was a requirement, the OEM would issue a disclaimer "USE OF FILTERS WITH NITRILE ADBV'S IS STRICTLY PROHIBITED".
Use the sensible logic train there. The ADBV doesn't have to hold indefinitely. It merely has to hold for so long.
That's not to say that some engine manufactures aren't using them to keep filters full. But it's a convenient co-product of the primary function of the thing.
If you don't hear start up rattle with a nitrile ADBV filter ..your engine has a lubrication system configuration that doesn't allow the filter to empty one way or another.
IF keeping the filter full ...with the specifying of a silicon ADBV was a requirement, then the "meets or exceeds" claim by EVERY filter man would be a bold faced lie. If it was a requirement, the OEM would issue a disclaimer "USE OF FILTERS WITH NITRILE ADBV'S IS STRICTLY PROHIBITED".
Use the sensible logic train there. The ADBV doesn't have to hold indefinitely. It merely has to hold for so long.
Originally Posted By: Gary Allan
Use the sensible logic train there. The ADBV doesn't have to hold indefinitely. It merely has to hold for so long.
How long? ... is there a test standard that defines this ADBV performance requirements?
Use the sensible logic train there. The ADBV doesn't have to hold indefinitely. It merely has to hold for so long.
How long? ... is there a test standard that defines this ADBV performance requirements?
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Originally Posted By: ZeeOSix
Originally Posted By: Gary Allan
Use the sensible logic train there. The ADBV doesn't have to hold indefinitely. It merely has to hold for so long.
How long? ... is there a test standard that defines this ADBV performance requirements?
Got me swinging as to how lone
. It's defined by the OEM. That's how the filter man's offer "meets or exceeds" the OEM spec. If they're not the assembly line producer, they have to reverse engineer them. Survey a number of the filter's for holding capacity ..bypass setting (some engines are quite specific) burst strength ..etc...etc.
I would venture that it most assuredly falls within the limits of a nitrile ADBV over the full duration of the OEM recommended interval. For some, that would have a 12-15k durability standard. We also know that most nitrile valves distort when cold after about 3k. Their hot oil holding time is probably quite long.
Originally Posted By: Gary Allan
Use the sensible logic train there. The ADBV doesn't have to hold indefinitely. It merely has to hold for so long.
How long? ... is there a test standard that defines this ADBV performance requirements?
Got me swinging as to how lone
I would venture that it most assuredly falls within the limits of a nitrile ADBV over the full duration of the OEM recommended interval. For some, that would have a 12-15k durability standard. We also know that most nitrile valves distort when cold after about 3k. Their hot oil holding time is probably quite long.
Originally Posted By: Gary Allan
Believe as you please. Pete C. from WIX has confirmed this many times. It's supported by the simple fact that IF it was ONLY there to keep the oil filter full ...EVERY nitrile ADBV would be a BUZZKILL FAIL.
I don't doubt the silicone ADBV is better. I have seen reasonable results, however, with nitrile, in keeping oil in the filters. Obviously, the lower the temperature, the greater the disparity in the performance between nitrile and silicone.
Originally Posted By: Gary Allan
IF keeping the filter full ...with the specifying of a silicon ADBV was a requirement, then the "meets or exceeds" claim by EVERY filter man would be a bold faced lie. If it was a requirement, the OEM would issue a disclaimer "USE OF FILTERS WITH NITRILE ADBV'S IS STRICTLY PROHIBITED".
Use the sensible logic train there. The ADBV doesn't have to hold indefinitely. It merely has to hold for so long.
How many carmakers actually require an ADBV when they come up with specifications for oil filters? I'm not trying to be a wise guy; I'm legitimately curious. Another question I'd have is how many filter manufacturers follow that. I know that nowadays, just about every filter manufacturer uses an ADBV whether needed or not (compare Wix with silicone ADBV and German filters with no ADBV for my Audi).
Ford's 300s didn't "require" an ADBV. They were nice to have, and came standard with the FL1A, when the CFL1 and other comparable filters of the day had none. Speaking from experience, even the nitrile ADBV made the oil changes less messy. Startup noise was also noticeably different - of course, I'm not talking about leaving the vehicle out in -40 C for two days, either.
As for nitrile, I still don't buy the argument about whether or not the purpose is to hold the oil in the filter or anything else. If oil drains out of the filter because of no ADBV or a cold ADBV, it's going to bring the oil out of the galleries with it.
Believe as you please. Pete C. from WIX has confirmed this many times. It's supported by the simple fact that IF it was ONLY there to keep the oil filter full ...EVERY nitrile ADBV would be a BUZZKILL FAIL.
I don't doubt the silicone ADBV is better. I have seen reasonable results, however, with nitrile, in keeping oil in the filters. Obviously, the lower the temperature, the greater the disparity in the performance between nitrile and silicone.
Originally Posted By: Gary Allan
IF keeping the filter full ...with the specifying of a silicon ADBV was a requirement, then the "meets or exceeds" claim by EVERY filter man would be a bold faced lie. If it was a requirement, the OEM would issue a disclaimer "USE OF FILTERS WITH NITRILE ADBV'S IS STRICTLY PROHIBITED".
Use the sensible logic train there. The ADBV doesn't have to hold indefinitely. It merely has to hold for so long.
How many carmakers actually require an ADBV when they come up with specifications for oil filters? I'm not trying to be a wise guy; I'm legitimately curious. Another question I'd have is how many filter manufacturers follow that. I know that nowadays, just about every filter manufacturer uses an ADBV whether needed or not (compare Wix with silicone ADBV and German filters with no ADBV for my Audi).
Ford's 300s didn't "require" an ADBV. They were nice to have, and came standard with the FL1A, when the CFL1 and other comparable filters of the day had none. Speaking from experience, even the nitrile ADBV made the oil changes less messy. Startup noise was also noticeably different - of course, I'm not talking about leaving the vehicle out in -40 C for two days, either.
As for nitrile, I still don't buy the argument about whether or not the purpose is to hold the oil in the filter or anything else. If oil drains out of the filter because of no ADBV or a cold ADBV, it's going to bring the oil out of the galleries with it.
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