Upside-Down Oil Filters and ADB Valve Effectiveness

[kanling]

I saw this as a comment as part of another long post

quote:

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I have been using Wix or Purolator; however, after changing my father's-in-law oil in a Camry with the completely empty-of- oil, upside down filter (Brand X ?), I will find out how good the ADBV of the Wix is.

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I was a little surprised. I figured that for engines with the filter mounted upside-down (I mean screwed onto a stud pointing to the ground), the filter would remain full of oil even if there were no anti-drainback valve at all. It would be just like the trap under a sink.

I suppose it would depend on how much air is in the system. Anybody have any comments?

I was hoping to be able to get by with a cheaper rebranded Wix on my Toyotas (with upside-down filters), figuring that I didn't really need the silicone ADB of a real Wix.

 

[Triple_Se7en]

I like Wix & Motorcraft ADBVs best for reliability/start-up. If I could find Donaldsons for my mid-size GM P/Us, I would include those too.

 

[T-Keith]

Again, the filter might not drain but the oil passages above the filter will. It still has a benefit.

 

[Jonny Z]

quote:

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Originally posted by kanling:
I was a little surprised. I figured that for engines with the filter mounted upside-down (I mean screwed onto a stud pointing to the ground), the filter would remain full of oil even if there were no anti-drainback valve at all. It would be just like the trap under a sink.

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I think up-side down meant hole down with the stud pointing upwards. There is a lot of confusion with what's up with a filter. (pun intended).

 

[kanling]

I don't know what year Camry the original poster was talking about, but in current models the filter is mounted to a down-pointing stud.

Anyway, I agree the oil passages above the filter and below the filter would empty without any ADB. I wonder how much pressure from the weight of the oil in the passages above the filter will be exerted to hold the ADB closed? If the back pressure is very low, I suspect the ADB would leak whether fancy silicone or not. Might also depend on whether silicone (or nitrile) floats in oil or sinks.

Hmmm. maybe we should send some oil filters to david letterman... will it float?

 

[kenw]

My 3 camrys (91 v6 RIP, 93 i4 and 97 v6) and the wife's Highlander with the 3.0L vvti v6 (same as the Camries of those years) all have "pointing up" oil filters, the kind that self drain the minute you unscrew them. At least on the Highlander (02) they added a drip tray to route the oil over and around the frame.

the holes are on the bottom, the closed can end is up. It's not 12 o'clock up, more like 10 o'clock.

 

[Pete C.]

Not to mention the fact that the media is porous and oil will also backflow thru it. Especially when the oil is hot. Sometimes we forget about this when we (dis)cuss ADB valves.

 

[kenw]

quote:

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Originally posted by Pete C.:
Not to mention the fact that the media is porous and oil will also backflow thru it. Especially when the oil is hot. Sometimes we forget about this when we (dis)cuss ADB valves.

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bingo!

hence my consternation with all the discussion of adbv...like what does it matter? (at least on all of my cars with hole-side down filters..)

 

[kanling]

Good point for hole side down filters! And half the oil will drain out through the media on sideways filters. There needs to be a check valve on the filter output, too.

You are right, I was assuming upside-down was "hole side up". So, apparently they totally reoriented the oil filter on newer Camrys. Maybe the new orientation is the best- less spillage and no seepage through the media.

 

[kenw]

I'm guessing by new camrys you mean the 3.3L/6 or 2.4L/4? Interesting that they made the change after so many years (and so many gallons of spilled oil...)

They still use the old 3.0L/6 vvti in some models.

 

[Gary Allan]

quote:

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There needs to be a check valve on the filter output, too.

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Yes, filters, if able to, will drain forward. I had to install sprung ball checks on the input and output of my remote mount since it sat higer than the valve cover. It would empty in both directions. IMHO, the ADBV isn't for keeping the filter full, although this is a good side/co-effect. I think it has to do with back flushing the media and sending debris back to the sump en mass. Admittedly, some filters don't have ADBV at all ..but I think if you take a closer look at the oil system on those applications, you may find that drain back isn't an issue with them.


Think for a moment: Filter without ADBV...does it have startup noise? Why not? Perhaps because the system that it's installed on is not subject to back flow?

 

[Big O Dave]

That's my experience with PF35L's on my SBC, Gary. No ADBV and no startup noise. I doubt there is any back-flow with this system.

 

[Ray H]

Why is this topic so difficult for some people? The ADBV's sole function is not to prevent drainage of oil out of the filter. It's to prevent CONTAMINATED oil from draining out of the filter. An oil filter is not a closed system. There's always a natural route for oil to drain from any oil filter - through the media. Oil that traverses through the media on its way back to the low point of an engine is FILTERED oil.

 

[Pete C.]

Ray H. Good statement above. The next question is kinda ****** if you get my meaning, maybe this will get it through the fog.

THE ADB VALVE PREVENTS THE OIL ON THE DIRTY SIDE OF THE FILTER ELEMENT FROM DRAINING BACK INTO THE ENGINE.

NO MATTER WHAT ORIENTATION IT IS IN

IF THE OIL DRAINS BACK INTO THE FILTER, FROM ANY POINT AFTER THE FILTER THE ADB VALVE PREVENTS IT FROM BACKWASHING THE FILTER INTO THE SUMP.

 

[kenw]

you're beating the wrong part, ray.

I asked for an explanation, and your's isn't it....please try again, i AM listening.

 

[Big O Dave]

So, we all agree that an anti-drain-BACK-valve keeps oil from draining BACK, but not forward.

Pete's only been back from Mississippi two days and already we've got him shouting! Excellent.

 

[Pete C.]

PFFFFFFFFFFFFFFFFFTTTTTTTTTTTTTTTT!!!!!

Sorry, but the GOOD LORD gave us all a brain, those that don't want to use it tick me off.

ARRRRRRRRRRRRRRRRRGGGGGGGGGGGGGGHHHHHHHHHHH!!!

 

[kenw]

ok pete, i'll type real slow so you can understand my question: I know what an ADBV does. That's not my question. Let's try asking it another way....

but first:

As the oil moves from bottom to top you have in order of flow and in really simple terms:

from the bottom going UP
1) pan
2) pump
3) filter
4) passages between the filter and places that need oil. I will have to assume that some of these are located ABOVE the filter
5) and finally: the top of the engine

then flowing back DOWN you have:
6) all the stuff that gets lubed
7) oil return passages
8) and lastly the pan

(feel free to make any corrections to my assumptions here, but remember they are simple for a reason)

So my re-stated question would be: where does the oil that is between the filter and the top of the engine (4 above) go when you shut of the engine? If it hasn't reached the top of its path, it can't flow down to the sump without going back thru the filter.

OK, so an adbv stops that flow. got it. no problemo.

but when i take off the filter, not that much comes out of the aforementioned filter-bottom holes. Just what was inside the filter and hasn't already drained.

And if I leave it long enough very little comes out those holes (again located DOWN, on the BOTTOM of the filter).

Where did it go (it=the oil that has been filtered and is physically BELOW the peak of it's particular path but ABOVE the filter)?

 

[Pete C.]

Next time open the ADB valve and see if your missing oil is there. Eventually the weight of the oil column and the cooling effect won't push any more oil thru the media.

The threaded hole in the middle of the filter is on the clean side. The small holes, that the ADB valve seals off, are on the dirty side. therefore any oil into the large threaded hole, in "THEORY", should not come out the small, sealed off, holes on the outside of the baseplate. That oil most likley leaks out of the system through the many other paths in the engine back to the oil pan. if the filter is above the oil level in the pan, and there is a direct route to the pan the oil could be siphoning back to the pan. even if it has to go up past the filter to get there.

Note the word "THEORY". It does not take into account a warped baseplate due to over tightening of the filter, or overpressurizing the filter, or even a manufacturing defect.

It does not take into account a defective ADB valve. Either from manufacturing, the installer sticking something into it to "SEE" what's behind it, or overheating.

It means exactly what it says in THEORY.

 

[Gary Allan]

kenw,

Look at a schematic of your block. If your filter is level with the main galley, then I would imagine that it would simply drain to the mains (typically downhill from there).


Btw- (and I think Pete C. confirmed my assertion) Who cares if you send dirty oil back to the crankcase? I mean to mix with the same EXACT composition oil that is already there??? This makes me chuckle a little. It wouldn't matter if the ADBV was on the head of the pump ..or wherever...it's just a divider between any point in the oil flow pre filter. The oil behind it is IDENTICAL to the oil in front of it.

That's why I say it's MAIN function is to prevent rapid backwash of the media ...NOT to prevent unfiltered oil cominglining with the same unfiltered oil in the sump. This is probably why even the cheapest filters manufactured rate their ADBV based on so many minutes of holding a seal. They don't care if it drains back in 3 hours or overnight. They just don't want for it to do an act like the backwash cycle on your swimming pool filter. Even Frams, with there notorious ADBV ..you will rarely hear start up rattle in anything except a prolonged shutdown.