Does the anti drain back valve matter?

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I own a 2008 Honda Accord V6. I have gained much knowledge from this forum. My question is this. My filter installs completely vertical and upside down (threads up). Would this filter location even require an anti drain back valve? Wouldn't it flow better without one?
 
My oil filter mounts the same way. I have been told that the anti-drainback valve (ADBV) also helps prevent oil from draining from the upper parts of the engine into the pan; I have my doubts about that, though, and I have never heard that anywhere else.
 
In short, yes, it still matters.

Without one, the head pressure in oil galleries above would "backflow" through the filter and you'd lose that oil pressure prime when you next start the engine. Even with a vertically-mounted filter, a good ADBV is important.

When you change the oil, you should notice that a good bit of "extra" oil drains out when you remove the filter. This is evidence that your ADBV is working as intended, and is keeping those oil galleries above the filter primed with oil.

Isn't the ADBV in the Honda Honeywell filters made of silicone? Honda must think enough of that feature to specify one to begin with, and specify one out of a premium material.
 
Originally Posted By: motor_oil_madman
Mine is vertically mounted and it doesn't have one.


Do you get much oil drain when you loosen the filter? The G6 is verticlly mounted as well and there is a fair amount of oil that drains when I crack the filter loose. So maybe there is something to it. You wouldn't think they'd spec the filter to have it if it's not needed. They could save some money on the cost of the filters and charge the same to sell them.
 
I was assuming (always a mistake) that when the oil filter was full of oil the hydrostatic pressure would keep the oil above it where it was supposed to stay.
 
I don't understand why this is even a question. Is it a matter of price? What's the cost difference between a filter with the ADBV vs one without it? $0.50 cents? Lol. Come on guys.

The best way to answer this question would be, what oil filter specs does the OEM filter have? If it comes with the ADBV, buy an aftermarket filter with the freakin valve. We're talking less then a buck worth here. Is the possibly for more engine wear and less overall engine life really worth it?
 
Originally Posted By: Artem
I don't understand why this is even a question. Is it a matter of price? What's the cost difference between a filter with the ADBV vs one without it? $0.50 cents? Lol. Come on guys.

The best way to answer this question would be, what oil filter specs does the OEM filter have? If it comes with the ADBV, buy an aftermarket filter with the freakin valve. We're talking less then a buck worth here. Is the possibly for more engine wear and less overall engine life really worth it?


Honestly, I wasn't thinking about this as a price issue. I was thinking that a filter that did not need an ADBV would flow more freely. I was thinking the OEM filter has one because it is spec'd for more than one engine. Some Honda engines that use this filter have it mounted on the side of the block thus needing the valve.
 
Mazda doesn't think it matters for its 2.3 engine. Mazda is shipping the cars equipped with the 2.3 with a filter that doesn't have the Anti-Drainback Valve.
 
When I remove my oil filter, I get a couple ounces of oil--maybe even less than 2 ounces--so it doesn't seem to be a big deal.
 
I always thought the antidrainback valve's main purpose was to prevent the filter from draining out. If the filter mounts vertically with the base end up, it should not matter. Yet both my Chevy 454 and ford 4.0 mount that way, the Chevy does not have an antidrainback, the Ford filter does.
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Seems it would matter to me. Case in point - did my first OC on the Focus yesterday since I got it.. When I took the filter off, quite a bit of oil came out, and was still draining from the engine mount when I took the filter off. I'd guess 1/2 quart or a little less. Needless to say I was quite surprised it was that much oil!

BTW, my wife's Highlander is the same way. Quite a bit of oil drains out when you take the filter off.
 
Originally Posted By: MysticGold04
...When I took the filter off, quite a bit of oil came out, and was still draining from the engine mount when I took the filter off. I'd guess 1/2 quart or a little less. ..
That is a whole lot. On the '92 Aerostar 3.0 the filter is right above the starter, so if you remove the filter from a hot engine the starter gets an oil bath, but I don't think anywhere near half a quart. If I changed the filter when it was cold, sitting overnight, practically no oil dripped so long as I didn't tilt the filter up. Not sure where the oil went from sitting cold. Maybe contraction when it cools?
 
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I have a big stash of Baldwin B6 filters. I got em cheap from a gas station that was closing it's doors. About a dime a piece. Have more than I'll ever use in my trucks lifetime. Anyways, it has no anti-drainback valve on it. I've been using it for years with no issues. Baldwins site calls for a B1428 for my truck, which has an ADBV in it. They are identical, except for the valve. The vehicle Im using it on is a 93 Chevy P.U. 2wd. It mount verticle.
 
Originally Posted By: TallPaul
If I changed the filter when it was cold, sitting overnight, practically no oil dripped so long as I didn't tilt the filter up. Not sure where the oil went from sitting cold. Maybe contraction when it cools?


If no oil drained out when cold, but you'd get oil out when hot, that's the perfect demonstration of the ADBV working (or not, in your case). It sounds like the ADBVs in your filters slowly let the oil passed against gravity. When changed hot, enough time hadn't elapsed for the oil in the galleries to drain back down to the sump against the ADBV. But after an overnight time period, all of the oil above the ADBV apparently leaked passed, and drained into the sump.
 
My 2011 forester has it vertical on the top of the engine.
It seems empty when I change the oil (warm-hot oil)
they also spec nitrile rubber adbv (black toyo-roki filter)... but no correct aftermarket filters are available yet so.. oem it is.
 
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Originally Posted By: Bruce T
Gary Allan had an interesting theory, that the ADBV prevents rapid backwashing of filter media (dislodging of contaminants]

No, it has to seep back through the oil pump. That's not rapid.
 
The anti-drainback valve can't work when an oil filter is mounted thread side up. If it did, it would be working against the direction of normal oil flow into the filter. That would be a bit of a problem when the engine was in operation.
 
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