Do You Pre Fill Your Oil Filter?

[ZeeOSix]

Originally Posted By: HangFire
Originally Posted By: dnewton3

4) The media will always be protected by the bypass valve, even if you don't fill and have a "dry start". The media is no more likely to be damaged at a dry start than when you open the BP valve during a cold start event with high-vis lube. I see this as the "ying" to the "yang" of pre-filling. Either way you're going to get unfiltered oil downstream of the media for a short time. Get over it guys; it' happens either way. And because of this, I lead into my final point ....


Bypass? This is WRONG from a fluid dynamics point of view, and those trying to use pre and post pressure sensors don't "get it" how fluid flow and pressure works in the presence of an air gap, especially at cold temperatures.

If oil practically never tears media, please explain the current Purolator situation, which may have correlation with the recent harsh Winter weather.

Also any manufacturer selling new oil not suitable for immediate lubrication duties would be driven off the market very quickly, as would every filter-less motorcycle and decades of outdoor power equipment engines.


The delta-p across the media is only dependent on the oil viscosity, oil flow and the resistance of the media. The delta-p across the media will be the same regardless if the oil filter is bone dry when the oil flow hits it, or if it's totally full of oil when the flow hits it.

If starting engines with bone dry oil filters was a dangerous thing to do that tore media all the time, then filter manufacturers would tell everyone to pre-fill the oil filter.

The media tears on Purolators has more factors involved then just cold thick oil in the winter months being flowed through them. Yes, it's one factor of many ... but a factor that "push the media over the edge" which could have contributed to the media to tears.

 

[HangFire]

We've had this discussion before. Since you refuse to see that the delta-P is different when the media is hydraulically supported, since you do not understand how the pre and post media sensors work in high flow/low resistance situation with one sensor in air, it is doubtful we'll get anywhere.

Tell you what, write controls code for a decade or two in automotive and production hydraulic environments and then get back to me.

 

[ZeeOSix]

^^^ Don't be so "snotty", and explain to everyone why you think the delta-p across the media will be different if the filter is bone-dry vs. completely wet with oil when the oil viscosity and flow rate is the same in both cases.

 

[Sayjac]

Quote:
..I would spill it anyway.

But you could accidentally drop sand, grit, or even the plastic ring from the bottle in the filter...

I use a small funnel to prefill my filters. Anything's (dirt/sand) possible I suppose, though very unlikely in my experience. Plastic ring, not sure how one would fit down the outlet hole under any normal circumstance, but with a funnel, not in this lifetime.

To each their own, where practicable I prefill.

 

[Kuato]

Originally Posted By: ZeeOSix
Originally Posted By: Kuato
Oh, and....

could it be possible that the sudden surge of oil against dry media is contributing in some way to all the media tears in some filters?


There is a sudden surge of oil every time you start the engine, or any time you punch the throttle. The "oil surge" against dry media shouldn't be any different or more stressful than the same surge when the filter is filled with oil. If it was, a lot of oil filters would be torn.



Think about it. Air is compressible. Oil is not. My thought was that in a dry filter the media could compress towards the center in the instants before the filter fills. This could flatten the pleats as well as partially collapse the inside tube structure if it is not strong enough. Any surges with the filter full of oil would not suffer the same issues since incoming fluid would be forcing out an equal volume which would provide resistance to collapsing anything. There would be some flexing of the media, but nowhere near as much as with a filter containing only air.


This begs the question as to the proportion of media tears that also suffered from a failed ADBV.

 

[Kuato]

Originally Posted By: mr_diy
Whenever possible. Whatever helps prime the oil system, same reason most filters have an anti-drain value. The pre-soaking cellulose based media and media equalization is also a benefit to minimize the initial force against media. Maybe partly responsible for my pre-filled P1's (Honda) holding up while my non fill-able P1's (Toyota) have shown media failures.

Just saw an episode of Wheeler Dealers where Edd pre-filled a filter.


Now.there is some evidence to support pre filling. Now we just need.the experiment done that Cooper suggested.

Edit: I am planning to perform this test on our Wrangler this October. I'll post the results.

 

[Yah-Tah-Hey]

+1

 

[ZeeOSix]

Originally Posted By: Kuato
Originally Posted By: ZeeOSix
Originally Posted By: Kuato
Oh, and....

could it be possible that the sudden surge of oil against dry media is contributing in some way to all the media tears in some filters?


There is a sudden surge of oil every time you start the engine, or any time you punch the throttle. The "oil surge" against dry media shouldn't be any different or more stressful than the same surge when the filter is filled with oil. If it was, a lot of oil filters would be torn.


Think about it. Air is compressible. Oil is not. My thought was that in a dry filter the media could compress towards the center in the instants before the filter fills. This could flatten the pleats as well as partially collapse the inside tube structure if it is not strong enough. Any surges with the filter full of oil would not suffer the same issues since incoming fluid would be forcing out an equal volume which would provide resistance to collapsing anything. There would be some flexing of the media, but nowhere near as much as with a filter containing only air.

This begs the question as to the proportion of media tears that also suffered from a failed ADBV.


Even if there is air in the filter that is not pre-filled, or not fully pre-filled, that air will easily be displaced by the oil when it starts to flow through the filter. Air will flow through the system easier than oil because air is much less dense than oil. The air is not going to compress because it has a path to flow out of the filter - that is into the engine's oiling circuit. Even though the engine's oiling circuit is more restrictive than the oil filter, it's not so restrictive that it's going to "trap" the air and make it compress. We are not talking about a lot of volume displacement at a start-up unless you start the engine and rev it to red line 1 second after staring the engine. At idle, the volumetric output of the oil pump is pretty small.

The pleats of the filter are not going to collapse due to the oil flow going through them even if there is air on the other side. The pleats will essentially see the same force due to the oil flow regardless if there is air or oil on the other side of the pleat. That's because the flow rate of the oil going through the media is the same if there is air or oil inside the filter. Trapped air inside a bone-dry filter upon start-up isn't going to impend any oil flow coming from the positive displacement oil pump.

If starting engines with completely dry oil filters was a major failure mechanism for the media, you would see more than just a few models of Purolator filters tearing up media.

 

[Kuato]

2 points-

1) hold a sheet of paper vertically with thumb and one finger. Squirt the dry lower edge with a kid's squirt gun. Repeat the experiment again, but this time be holding the sheet of paper in a pool of still water. In which medium would the paper move more/more quickly?

2) Why do we fuss so much about the adbv in a filter if it doesn't matter if there is air or oil in the filter?

Anyway....We could debate all week, and neither of us have a shred of evidence. I will do the experiment*.









*Yes I am aware that a single test with 2 filters will not be statitically significant. Even if I did it 3 times using 6 filters there are many that would scoff. But it will be done with 6 randomly selected Purolator Classic filters, bought at the same time from the same source.

 

[ZeeOSix]

Originally Posted By: Kuato
2 points-

1) hold a sheet of paper vertically with thumb and one finger. Squirt the dry lower edge with a kid's squirt gun. Repeat the experiment again, but this time be holding the sheet of paper in a pool of still water. In which medium would the paper move more/more quickly?


Not really sure what you're tying to show with this "analogy" (?). Understand that a positive displacement will move the same volume of oil to and through the oil filter (and engine's oiling circuit) regardless if the oiling system is filled 100% with oil or filled with air.

The only thing someone could argue is if the media has less resistance to flow when it's wet with oil vs. dry with air. I doubt there is any real difference when a positive displacement oil pump is forcing the oil through the filter and engine, regardless if air is being pushed out of the way from the wall of oil coming down from the pump.

Originally Posted By: Kuato

2) Why do we fuss so much about the adbv in a filter if it doesn't matter if there is air or oil in the filter?


The sole purpose of the ADBV is to keep oil from back-draining from the engine's oiling circuit back into the oil pan and potentially cause noisy start-ups due to lack of oil flow and oil pressure to engine parts in the first few seconds after start-up. Some engines are more sensitive to "dry-starts" than others.

You want a real experiment, put a filter on your car that doesn't have an ADBV so the filter drains out every time the engine is shut off so it get's a "dry start" every time. If it's not a Purolator, it will probably not show any torn media.

 

[ZeeOSix]

Originally Posted By: mr_diy
Maybe partly responsible for my pre-filled P1's (Honda) holding up while my non fill-able P1's (Toyota) have shown media failures.


What are the two PureOne filter numbers involved. Not all Purolators filters are susceptible to tearing.

 

[Kuato]

Originally Posted By: ZeeOSix
Originally Posted By: Kuato
2 points-

1) hold a sheet of paper vertically with thumb and one finger. Squirt the dry lower edge with a kid's squirt gun. Repeat the experiment again, but this time be holding the sheet of paper in a pool of still water. In which medium would the paper move more/more quickly?


Not really sure what you're tying to show with this "analogy" (?). Understand that a positive displacement will move the same volume of oil to and through the oil filter (and engine's oiling circuit) regardless if the oiling system is filled 100% with oil or filled with air.

The only thing someone could argue is if the media has less resistance to flow when it's wet with oil vs. dry with air. I doubt there is any real difference when a positive displacement oil pump is forcing the oil through the filter and engine, regardless if air is being pushed out of the way from the wall of oil coming down from the pump.


Common sense will tell you I am trying to show that in air, the water stream will move the paper further than it will when the paper is in water. This is to back up my assertion that the paper media is less likely to collapse when the filter is filled with oil than when it is dry and filled with air. If you can't understand that, I give up.

 

[ZeeOSix]

Originally Posted By: Kuato
Common sense will tell you I am trying to show that in air, the water stream will move the paper further than it will when the paper is in water. This is to back up my assertion that the paper media is less likely to collapse when the filter is filled with oil than when it is dry and filled with air. If you can't understand that, I give up.


Not a real good analogy; but at any rate if you squirt a dry piece of paper or a wet piece of paper, there is still the same basic force and movement of the paper from the water stream ... even if it's underwater and the spay nozzle is right up against the paper in all cases - which it would have to be to be anywhere close to analogous to the flow inside an oil filter.

The force on the media is a function of the oil viscosity and the oil flow volume flowing through the media. The thicker the oil and the higher the oil flow, the greater the delta-p and the greater the force impinged on the media. The force on the media will essentially be the same regardless if there is oil or air inside the filter when the oil flow enters the filter and flows through the media.

 

[Kuato]

Well it's obvious all you want to do is argue and tell everyone they are wrong.

I give up.

 

[ZeeOSix]

Originally Posted By: Kuato
Well it's obvious all you want to do is argue and tell everyone they are wrong.

I give up.


I'm just saying how I see it, not arguing ... you can believe it or not. Let us know how those experiments go.

 

[Noshow13]

Originally Posted By: Oregoonian
Originally Posted By: tstep
I'll put some oil in the filter, but not full. Maybe 1/2 to 3/4 depending on the limbo the filter needs to do to get into place without spillage.

+1.....enough to avoid spillage....but I frankly think that it makes little difference as I understand that oil gets to the necessary area in a fraction of a second.

I do the same.

 

[mr_diy]

Originally Posted By: ZeeOSix
Originally Posted By: mr_diy
Maybe partly responsible for my pre-filled P1's (Honda) holding up while my non fill-able P1's (Toyota) have shown media failures.


What are the two PureOne filter numbers involved. Not all Purolators filters are susceptible to tearing.


The Honda uses PL14610 and Toyota PL10241, both have been reported with tears. One was even the save year Civic (by trx250x92). I currently have 6 of each used and cut open. The 10241's do have worse pleat spacing. The Civic filters have been run for the full OLM value, 7300 to 8800 miles.

BTW, movement of media or anything is dependent on the force on each side not just one side. Now you may try to make the case the weight of oil verses air can be neglected, but show the math.

The media failures having one of two root causes; one being the wide spaced pleats having less support and in other cases the glue letting loose.

Regarding wetted media resistance, a easy test may be for someone to take two new P1's and set up a basic flow test through the center tube. One pre-soaked, the other dry. Certainly when filling filters it takes multiple fills (4-6) before the level holds steady.

 

[ZeeOSix]

Originally Posted By: mr_diy

BTW, movement of media or anything is dependent on the force on each side not just one side. Now you may try to make the case the weight of oil verses air can be neglected, but show the math.


Exactly, and what caused the force on the media is the delta-p across the media. If you had an oil filter that was feed by a positive displacement oil pump that was not screwed on to an engine and just hanging in the air, and pumped 3 GPM of oil at viscosity X through it, there would be Y PSI of delta-p across the media ... even though all the oil is exiting just in to the air on the down stream side of the media and out the center hole in the base plate.

The same delta-p will be seen if the filter is mounted on the engine, and under the same viscosity and flow conditions. The delta-p is only dependent on the oil viscosity and the flow rate through the media ... doesn't matter what's on the other side of the wall of media. The down stream side of the media could be at 0 PSI gauge (atmosphere), or at 200 PSI gauge ... but the delta-p will be the same if the viscosity and flow rate is the same across the media in both cases.

Originally Posted By: mr_diy
The media failures having one of two root causes; one being the wide spaced pleats having less support and in other cases the glue letting loose.


Many members here have also said that the root cause is most likely the wide pleat spacing, and more so the large "V-spread" of those pleats next to the seam. Too much force on those pleats wants to push them inward which results in the media tearing at the ends where glued in ot the end caps. We have also seen many cut open Purolators with wide pleat spacing next to the seam, but very little V-spread and there were no tears on those filters. If you made a filter with every pleat having a very large V-spread, it's possible many pleats could tear depending on the strength of the media and the operating conditions the media is subjected to (ie, oil thickness and oil flow volume).

Originally Posted By: mr_diy
Regarding wetted media resistance, a easy test may be for someone to take two new P1's and set up a basic flow test through the center tube. One pre-soaked, the other dry. Certainly when filling filters it takes multiple fills (4-6) before the level holds steady.


Might not be a very good test for what we are discussing. Reason why is because in the test you describe, there will be initial wicking of the oil into the dry media. Since the driving force to make the oil flow through the media is so small (super small amount of head pressure in the center tube), you might even find that the dry media will "flow" better due to wicking than the wetted media. You could try it out and see what you find ... might be interesting.

================================

On a side note, think of this. The media is designed to take at least a delta-p without failure (you would expect/hope) that would be developed in order to open the bypass valve. That's around 12~16 PSID for most oil filters.

There is nowhere near 12~16 PSID developed across an oil filter during an engine start with a dry filter - especially at engine idle speed. It just can't develop anywhere near that much PSID under those conditions, unless it was totally clogged, but we are talking about new filters here.

I do however think that the rash of Purolator's seen with torn media this spring were probably subjected to some harsh cold weather, and under those conditions the oil is pretty thick which could have caused a large PSID spike during a cold start which the bypass valve couldn't handle quick enough. But with the Purolators that had wide pleats and large V-spread on the pleats, they probably tore way before the bypass valve level of PSID was ever achieved.

Many factors involved with the media tearing issue, but I think the not pre-filling the filter is not really one of the real factors.

 

[Rat407]

I prefill with Extra Virgin Olive oil.

 

[Stelth]

Just to add to the confusion, I'll point out that Purolator, in their FAQ, doesn't recommend pre-filling oil filters: Purolator FAQ

Fram, in their installation video, also shows dry installation of the oil filter.

Hastings also shows dry installation.

Interestingly, Luber-Finer says that some turbocharged engines may require pre-filling of the oil filter. Luber Finer video

Baldwin also says that some manufacturers may require pre-filling of oil filters: Baldwin Engineering Bulletin 99-4

In TSB 93-3R1, Baldwin also says that pre-filling oil filters for some turbocharged engines may be required.

Curioser and curioser. In any case, I don't have any turbocharged engines currently, and two of the engines I service (Nissan and Toyota) are mounted in positions that don't allow pre-filling.