Which brand of oil filter has the best anti-drainback valve?

[MNgopher]

Comment #1: It would be a waste to install a check valve if the only goal is to prevent unfiltered oil from getting back to the sump. Afterall, where is the oil going to go besides the sump? From there it is pumped through the filter anyways. It is going to get filtered. Everything between the filter and sump sees unfiltered oil all the time. The sump is full of oil that has been in the engine and full of the stuff that needs filtering.

Comment #2: Filters in a vertical mount situation (filter opening towards the ground) may indeed pass all of the oil in the fiter into the passages after the filter, leaving the filter itself dry. It just depends on the level of the passages after the filter. Setups like this in all likelyhood never needed the ADBV, but they were used for commonality in a product lineup.

 

[JohnBrowning]

Well I can tell you I have never had a dry filter ever. I have had some that did a better job then others based on how much oil I got out. THe Motorcraft FL1A and Baldwin B2 by far did the best job. THe B2 was full right up to the top!!! I have never had valve train noise on any of my vechiles but I never used a Fram on a vechile with hydralic valve train either. I think in my case my avoidence of Fram is more of a precautionary messure! Why use something that cost more and offers less build quality? WHy risk an expensive engine to a filter of chaep design and construction? Consumer confidence is just as important as actual performance! Look at Castrol and the "synthetic" shanagans! I used castrol most of my life and so did my dad and my friends. It was always Castrol GTX and a Fram filter!

 

[Chris A]

I don't have any oil filter experience. I do have a brain, and my opinions are based on how my brain works and my experience with non-ADBV filters on various SBCs (PF25, PF35, PF58).

I pretty much agree with what Ray H says.
I also agree that there must be some type of check valve in the oil pump. I say this because I have *never* removed an upright oil filter that I did not get oil pouring down the sides once loosened. This includes oil changes I've done where the oil was cold (ie not driven for many hours).

quote:

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Originally posted by MNgopher:
Comment #1: It would be a waste to install a check valve if the only goal is to prevent unfiltered oil from getting back to the sump. Afterall, where is the oil going to go besides the sump? From there it is pumped through the filter anyways. It is going to get filtered. Everything between the filter and sump sees unfiltered oil all the time. The sump is full of oil that has been in the engine and full of the stuff that needs filtering.

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It's not the oil that I believe needs to be kept out of the sump, it's the junk in the filter. The ADBV is the only thing that keeps the stuff that the filter already caught from dropping back in if there was a reverse of the oil flow (ie gravity).

This is really easy to prove as to if the oil is kept in the filter. Pull the filter after letting the car sit overnight and see how much oil is left in it. My guess is that once the filter is inverted so the mounting is up, it will be less than 1/4 full.

 

[MNgopher]

But where would any of this so called junk in sump go? Its already got "junk" in it from coming through the motor. Whats some more from the filter? Either way, it can only go one of two places: Through the filter via the oil pump (which is already pumping "contaminated" oil that needs filtering) - or out the drain when doing an oil change.

 

[Chris A]

In my mind, the oil filter's job is to keep junk out of the oil. Why would you want to let junk that was already trapped back into the sump? That's not a good idea.

The other place oil can go is through the filter bypass valve and into your engine, which I believe happens at least during cold starts.

 

[oilyriser]

Yesterday, I changed oil and filter on my mom's Subaru, and noticed that the oil flowed freely from the inlet holes of the filter. This was a Pure 1, after 8 months on Castrol 0w30 (gc). I've had Frams where the ADB valve worked so well that I had to poke a wire in the holes to open it up and let out more of the used oil. This is the second time I remember a Pure 1 ADB valve failing to hold in the oil as I handle the old filter.

I replaced it with a Supertech that I bought while visiting the US. The customs guys must think I'm nuts when I show them a bag full of oil filters.

 

[edhackett]

Oilyriser,

A Subaru specification oil filter for the four cylinder engines does not have and ADB. It's not needed due to the mounting position.

Ed

 

[TheNauseator]

[ December 10, 2003, 05:21 PM: Message edited by: TheNauseator ]

 

[TheNauseator]

quote:

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Originally posted by TheNauseator:

Originally posted by cryptokid:
[qb] the adbv in my opinion is over rated.

it only holds oil in half the filter (remember there is an inlet and an outlet. you cant plug one hole and leave the other open and expect it to stay 100% full)

thats like putting a cap on a bottle of water to prevent evaporation, and not doing anything about the hole in the bottom of the bottle.

although that analogy is not entirely accurate for this discussion, as the adbv WILL help, but it is still over rated.

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The filter i my VW is installed nearly vertically and every time I change the oil, the filter is full of oil all the way to the top and I drain nearly 3/4 of a quart of oil for the filter alone. I guess a good, tight ADBV is very important.
edit: filter is installed vertically with the thread facing up.

 

[oilyriser]

"A Subaru specification oil filter for the four cylinder engines does not have and ADB"


Hey, you're right. I just checked Purolator's website. The 14460 does not have an ADB valve. The catalogs used to specify the 14459, which does have the valve. But the 14460 looks like it has the valve. Maybe that ornage silicone thing is backed off a bit so that it doesn't seal gainst the inlet holes.

My own car made a rattle for the first few
seconds after starting, using the 14459, which went away when I installed a Canadian Tire rebranded Fram. Maybe it was flow restriction issue and not a failed ADV valve. I'm experimenting.

The 14460 has a relief valve setting of 20-25 psi. I don't like the idea of subjecting a paper filter to 25 psi, so I will stay with the 14459 if I use it again.

 

[TC]

Oilyriser: FYI... You might want to look into the L/PL24458. These are standard replacement filters for Hondas from the late 1980s, have the same diameter and gasket as the 14459, and are 1" longer. By my measurements, they have roughly 50% more media than the 14459. I don't know about the 24458 bypass setting, but assume it's perfectly compatible with the media used.