ADBV

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Is the following statement true?

"plain fram dosent have the anti drain back valve.The tough guard does.Same with puralator.The pur one filter has the anti drain back valve.Not the plain puralator"

I don`t think it is.Off a Dodge Dakota forum started by a guy who said dealer mechanic told him cheap filters don`t have one so use a Mopar filter.

I realize some ADBV`s are better than others but don`t all filters have one?

Thanks in advance
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Here`s the original post I was talking about;

"Had a Dodge parts manager tell me the other day that mopar's oil filters have a check valve in them to keep all the oil from draining down into the pan which obviously keeps some lube up top which is good for cold start-ups. He said there aren't many other filters available that have this feature. Anyone know anything about this?"

I hate misinformation like this.
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My GM V8 engines all have had vertically mounted filters so the oil drains into the filter. No ADBV needed. My other 2 cars Honda CRV & Lexus rx330 have horizontally mounted and ADBV is critical. Is this correct?
 
If the filter is mounted upside down then an ADBV is completely unnecessary as gravity will ensure that the filter is always full of oil. That being said, the presence of an ADBV in the case of an inverted filter will do no harm.
 
In any engine where the oil passage goes upward after leaving the filter, an ADBV can have an effect on the speed at which oil reaches various components in an engine upon start-up. For instance, on the 3.4L Chevy, the oil filter threads onto a 6” long by 3/4” diameter tube that slants at about a 45degree angle upward (inside the block). If the ADBV doesn't leak, this tube will stay nearly full of oil after the engine is shut off. Therefore, the effect of an ADVB can also be dependent on engine internals, even on engines where the filter mounts closed end down.
 
Thanks Brian, It is unbelievable how many times on this forum we have told people that the orientation of the filter does not mean that much. In a chevy V8 especially you can tell that the light takes a lot longer to go out if the valve is missing or not working right. On my 4.3 6 which is the same basic pattern the light goes out in less than a second from cold startup.
 
The orientation of the filter does affect the need for an ADBV. I have a 2002 Subaru Outback 2.5L with the oil filter mounted upside down and guess what? The Purolator L 14460 oil filter for it does not have an ADBV. All other cars I have owned or worked on had oil filters that were not mounted this way and they all had ADBV's. Even if only partially inverted they should have an ADBV as some of the oil will drain out but if mounted completely upside down ADBV not needed.
 
You can usually tell by looking at the filter’s inlet holes. These are the several holes or slots in a circular pattern around the larger outlet hole in the center. Generally speaking, if those inlet holes are covered (on the inside of the filter) by rubber (usually black or orange), the filter has an ADBV.
 
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The orientation of the filter does affect the need for an ADBV.


The need for, or usefulness of, an ADBV depends upon more than the filter’s orientation. As I pointed out above, even an engine with a filter mounted with the open end up can benefit from an ADBV. Given certain design limitations and considerations, an engine designer may choose to mount the filter open end down and omit an ADBV. The point is, one shouldn’t judge the need or usefulness of an ADBV based on filter orientation alone.

I'm not an engine or oil filter designer, but I can see only two reasons to omit an ADBV from an oil filter: Cost and environmental concerns. I'm unaware of any technological drawbacks that the presence of an ADBV can have on a filter or the engine. Perhaps there is some slight increase in differential pressure at a given flow, but that would seem to be insignificant.
 
I don't want to belabor the point, but the necessity of an Anti Drain-back Valve depends entirely upon the presence of factors that would cause the oil to "Drain Back". The only factor I can think of is gravity. If gravity is preventing the oil from "draining back" and the oil filter remains full of oil when the engine is shut off, what else is there to consider? If the oil doesn't "drain back", why would an anti drain back valve be necessary? The only thing I can think of affecting the impact of gravity on the contents of an oil filter with the engine off is it's orientation to the earth's surface. Am I missing something?
 
You need to think outside the oil filter. An ADBV can prevent not only the oil in the filter from draining due to gravity, but any oil in passages above the oil filter.

Picture a filter sitting open end up with a 6 inch long straight pipe welded to the outlet hole, all full of oil. With an ADBV not only can the filter stay full of oil, but the 6 inch pipe can also stay full of oil. Without an ADBV, oil will begin slowly draining out of the filter inlet holes until the pipe is empty (though the filter will remain full).

Next, add 24 inches of hose to the pipe and fill it with oil. Now, invert the filter and pipe (open end down) while keeping the open of the hose pointed up (the whole works is sorta shaped in a “J”). If the filter has no ADBV, nearly all of the oil will slowly drain out except for a little in the pipe and some of the hose (basically all the oil above the filter base). However, if the filter has an ADBV that seals, essentially all the oil will remain in the filter, pipe, and tubing, even though the filter is mounted open side down and the filter base is several inches below the end of the hose.

In both of the above filter orientations (oil filter holes up, oil filter holes down), some oil drains out of the setup when no ADBV was present. But with an ADBV, essentially all the oil remains in the setup, regardless of filter orientation.

Warning: If you wish to try this little test at home make sure you several quarts of oil, and plenty of rags and clothes washer detergent on hand before starting. I won’t be responsible for the outcome or any consequences of performing the above tests in your kitchen.
 
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Warning: If you wish to try this little test at home make sure you several quarts of oil, and plenty of rags and clothes washer detergent on hand before starting. I won’t be responsible for the outcome or any consequences of performing the above tests in your kitchen.




LMAO....
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"Picture a filter sitting open end up with a 6 inch long straight pipe welded to the outlet hole, all full of oil. With an ADBV not only can the filter stay full of oil, but the 6 inch pipe can also stay full of oil. Without an ADBV, oil will begin slowly draining out of the filter inlet holes until the pipe is empty (though the filter will remain full)."

If the oil filter is upside down and full of oil, where would the oil from the tube drain to? You can't overfill a filter that's already full of oil. I still don't understand what you're saying at all.
 
With no ADBV oil will drain out of the inlet holes until the tube is empty (though the filter would remain full). With an ADBV, all the oil will remain in both the tube and the filter.
 
But how can oil drain out of the inlet holes of the filter against gravity, going "uphill", if the filter is mounted vertically with the open end facing directly up? Gravity will keep the filter full of oil, any draining would defy the law of gravity.
 
Siphon. That gives you the impression of defying gravity. The filters that have no ADBV must be in engines that are so configured as not to have an backflow when shut down ...at least any rapid back flow. The ADBV wasn't conceived to keep the filter full. The OEM spec's on them are that they hold for a certain time duration. Otherwise Fram would be a prohibited filter for every engine while in warranty. It's to prevent the filter from back flushing (height in the block in relation to the sump level - whatever
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). Now some recent engine evolutions appear to benefit from ADBVs that actually hold ..like your modular engines ..but, again, Fram provides a number for them too ..and it has no "S" at the end of it (at least I don't think it does). I still think that it's to reduce customer complaints over start up rattle.
 
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