Anti drain back valves

Status
Not open for further replies.
Joined
Jan 10, 2008
Messages
356
Location
KS
Just form reading around, whats the purpose of the ADBV and whats better, a nitrile adbv or a silicone one?
 
welcome2.gif
The intended purpose of the ADBV is to prevent rapid backflushing of the media. The extended purpose is to keep the filter full. It's typically not an OEM requirement.

Nitrile is cheaper and fatigues over time. Silicon remains pliable over longer periods of time.

Ford has some engines that they want to assure that the valve holds. Those you will see with an "S" in the number (MotorCraft) FL400S ..etc.
 
So some filters don't even have ADBVs? Do filters actually completely fill up with [censored] from inside the motor?
 
Last edited:
I'm sure some filters dont have them, but I've never seen one that didnt. Some filters dont have a pressure bypass valve if you're thinking about that and confusing the two.
 
oh

What do you mean by rapid backflushing of the media? What was the problem fram had with their tough guards, I think it had to do with cardboard adbvs or something
 
The issue with some Fram filters is they have cardboard endcaps rather than metal or plastic, some of which has ended up inside the engine and upset people before.
 
Originally Posted By: 7055
oh

What do you mean by rapid backflushing of the media? What was the problem fram had with their tough guards, I think it had to do with cardboard adbvs or something


I mean that most ADBV spec's don't require it to hold 24/7 365. They spec's are to hold for xx amount of time. This is to stop the back flushing of the media. Faster backflow ..more dislodged debris.

Think about it, if the true purpose of an ADBV was to assure a full filter, and this was a REQUIRED item in the construction of the filter for the GOOD of the engine, wouldn't you think that EVERY engine manufacturer would INSIST on a silicon ADBV and PROHIBIT any filter that leaked down?

Frams and quite a few other nitrile equipped filters would be on some DO NOT USE list. Yet a Fram, with all kinds of start up rattle, is perfectly fine for a 100% of the factory recommended OCI and it meets or exceeds OEM specifications.

Now I know what you're thinking, what about Ford with the "S" suffix. I would say that either Ford doesn't like customer complaints about startup rattle, or they actually engineered a few engines that ALSO require a full filter for a preferred startup.
 
They can surely drain forward or backward ..but with an ADBV the reverse flow will be slower. The horizontally (not inverted) would merely empty until the top of the filter gets exposed.
 
Sure ..probably. A silicon valve may be too.
21.gif
That's why, in most cases, it's an annoyance more than anything else. If it was considered a REAL problem, the OEM spec would insist that ALL filters have a silicon ADBV and that they hold indefinitely. They don't, otherwise Fram, Purolator (PP), NAPA Proselect, ST..etc could not say "meets or exceeds OEM specifications".
 
Originally Posted By: Dyoel182
The issue with some Fram filters is they have cardboard endcaps rather than metal or plastic, some of which has ended up inside the engine and upset people before.


Which would cause dirty motor oil to clow into the crankcase right?

Correct me if I'm wrong, I get the idea a failing adbv isn't really going to affect engine longevity its just going to make it louder on startup because the filter isn't filled up yet?
 
Last edited:
Dirty oil is going to flow into the crankcase regardless. The cardboard endcap and string tied around the filter element just make it feel cheaper and actually be cheaper.

As for a failing ADBV, I'm not sure they can really fail. Unless you left that filter on the car for a long time the valve is going to at least mostly seal up when the pressure drops and oil will stay in the filter regardless. IMO the startup noise caused by using a nitrile valve over a silicone valve is unfounded.
 
Last edited:
My neighbor has a mobile oil change business. They work exclusively on rental cars changing oil on 40-50 a day right in the parking lot. For all cars and trucks except Fords they use the cheapest bulk filter they can get. These junk filters cost him $1.50 each. He is required to use a Motorcraft filter on all the Fords and has to stock those in his van alongside the no name filters. When I asked him why he was required to use the Motorcraft filter he mentioned the ADBV. To Ford (and rental car agencies with Ford fleets) it seems mighty important to use a filter with a good ADBV such as Motorcraft.
 
Quote:
Which would cause dirty motor oil to clow into the crankcase right?


Back into the same location that it came from and mix with the same oil that's in the exact same condition? I'm afraid so
frown.gif


21.gif



55.gif
 
Originally Posted By: Steelers
To Ford (and rental car agencies with Ford fleets) it seems mighty important to use a filter with a good ADBV such as Motorcraft.


Its always made me wonder when Ford lists their filter for cars but then you go to a Mazda with the exact same engine and there is no mention of it, even on engines designed by Mazda and built for Ford they seem to do it (and then you can never find the filter).
 
Status
Not open for further replies.
Back
Top Bottom