Capacity vs. Flow: Amsoil - Ea Oil Filter

[blackdiamond]

Let me preface my question by saying that I am not disputing the quality of an Amsoil filters, in fact I have two in my garage ready to go on my 4Runner, and my question probably has application to ALL filters. The Amsoil website just provided a good example.

From the website: "AMSOIL Ea Oil Filters have significantly lower restriction than conventional cellulose media filters. Their small synthetic nanofibers trap smaller particles and hold more contaminants, resulting in lower restriction. During cold temperature warm-up periods, an EaO lube filter allows the oil to easily flow through the filter compared to a typical cellulose filter. Lower restriction decreases engine wear."

It seems that not useing any type of filter would result in zero flow restriction (obviously other issues with this plan) so how can a filter that hold more, and smaller, contaminants still flow better?

How does the flow of a filter change over time as it begins to reach capacity?

 

[Pablo]

I guess for me to conceptualize what goes on in an oil filter I must put my mind in 3D mode. If these smaller particles are caught throughout the media, then there is plenty of flow around.....but all these particles are not the same size, so as the larger ones are caught first the smaller ones make it through until "their time comes" and they get lodged....so to speak. And yes eventually flow will slow (but pressure remains the same)....but in a clean burning car with a great air filter and good oil, this will be a long time. (Unless the engine is full of crud to start with)

 

[blackdiamond]

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I guess for me to conceptualize what goes on in an oil filter I must put my mind in 3D mode. If these smaller particles are caught throughout the media, then there is plenty of flow around.....but all these particles are not the same size, so as the larger ones are caught first the smaller ones make it through until "their time comes" and they get lodged....so to speak. And yes eventually flow will slow (but pressure remains the same)....but in a clean burning car with a great air filter and good oil, this will be a long time. (Unless the engine is full of crud to start with)

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I understand that larger particles will get filtered out at a higher efficiency that smaller particles, but it seems that the smaller particles (advertised as 98.7 percent at 15 microns) would "clog" the filter faster than larger ones because smaller areas are left for the oil to flow through. Higher efficiency filters generally, if not always, have larger capacity (Mobil 1 is advertised as 2x I think) but it doesn't seem that it would be good for twice as long since it is, in theory, capturing more junk.

As an example, I would expect an Amsoil Ea filter with the same filter area to clog up much faster than one that filtered less efficiently.

 

[oilboy123]

What about filter area x media depth?

The depth or thickness would make a big difference.

 

[blackdiamond]

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What about filter area x media depth?

The depth or thickness would make a big difference.

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Are you talking about the pleats?

 

[TimVipond]

The trick is the Amsoil filter fibers are 1/10th the diameter of conventional fibers. So the smaller fibers allow much more surface area and smaller pore space to trap more and smaller particles and with more open pores, impede the flow less.

Oil flow through a filter does slowly degrade over time and and when the filter nears maximum particle capacity, flow is reduced and filter pressure is increased. If this continues, the filter will go into bypass mode when it reaches a specified pressure and the oil is rerouted around the filter media.

 

[Gary Allan]

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Oil flow through a filter does slowly degrade over time and and when the filter nears maximum particle capacity, flow is reduced and filter pressure is increased. If this continues, the filter will go into bypass mode when it reaches a specified pressure and the oil is rerouted around the filter media.

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Well, let's think about this a bit. I'd say that flow doesn't degrade at all. You'll just have oil accelerating through whatever available passages/pores as the filter heads toward saturation. The feature with synthetic medias, as I understand it, is their more uniform pore size. The cellulose medias allegedly have a wider variance of pore size. This causes the larger pores to see most of the oil flow until they are clogged. Then the oil is forced through finer and finer pores. That's why most filters improve with age.

In my opinion, based on observations and personal testing, I really doubt that anyone, doing anything up to 15k OCIs ... in a contemporary engine, can saturate a filter to the point where it is bypass for anything but "transitions" (startup, perhaps briefly during warmup, flat shifting @ 7000rpm). Some minor and obscure conditions and restrictions apply.

A filter, in an otherwise sound engine, cannot, by itself, alter flow. It has to be in concert with the oil pump being in relief (in the case of a worn oil pump- virtual relief).

 

[harry j]

By it's nature, the nano fiber filter will allow 100% oil flow throughout the working surface. A paper type filter will pass oil only by 60% of the surface presented to the oil flow. Paper being what it is, the pore sizes vary from non-existant to mayby 50 microns or more! Nano fiber material on the other hand, has a more uniform pore pattern, allowing better filtration, debris capacity and the all important oil flow. I have experienced this effect myself. Not only is my oil kept cleaner than it ever has been, but the valve train clatter is now gone.

Harry

 

[ewetho]

Simply think of a square with 50 holes. Now the same size square with 250 holes. When you stop a particle you clog a hole. With the finer mesh you have more holes to clog. Also more are to flow oil. So while you may have plugged the filter media of a regular filter the new amsoil one would still have 1/2 to 1/3 of the maybe more of the media still flowing.

Takes more dirt. THink of a screen door and then think of a plate of steel in place with less than half of the number f holes. Which would clog first. Passing the same amount of air.

 

[Steve S]

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Oil flow through a filter does slowly degrade over time and and when the filter nears maximum particle capacity, flow is reduced and filter pressure is increased. If this continues, the filter will go into bypass mode when it reaches a specified pressure and the oil is rerouted around the filter media.

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Well, let's think about this a bit. I'd say that flow doesn't degrade at all. You'll just have oil accelerating through whatever available passages/pores as the filter heads toward saturation. The feature with synthetic medias, as I understand it, is their more uniform pore size. The cellulose medias allegedly have a wider variance of pore size. This causes the larger pores to see most of the oil flow until they are clogged. Then the oil is forced through finer and finer pores. That's why most filters improve with age.

In my opinion, based on observations and personal testing, I really doubt that anyone, doing anything up to 15k OCIs ... in a contemporary engine, can saturate a filter to the point where it is bypass for anything but "transitions" (startup, perhaps briefly during warmup, flat shifting @ 7000rpm). Some minor and obscure conditions and restrictions apply.

A filter, in an otherwise sound engine, cannot, by itself, alter flow. It has to be in concert with the oil pump being in relief (in the case of a worn oil pump- virtual relief).

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Gary!!! if the oil accelerates through smaller holes then there is a pressure increase. To increase pressure ,increase restriction. Stuff "fluids / Gasses" accelerate through a restriction. Nozzel on a garden hose for example. P.S. there are more pores in the syn media . The syn media is finer so there is less restriction from the media . on and on.

 

[Gary Allan]

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Gary!!! if the oil accelerates through smaller holes then there is a pressure increase. To increase pressure ,increase restriction. Stuff "fluids / Gasses" accelerate through a restriction. Nozzel on a garden hose for example. P.S. there are more pores in the syn media . The syn media is finer so there is less restriction from the media . on and on.

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You're viewing it out of context there, Steve. You're viewing it just like you said, a nozzle ..a water faucet...all situations where you've got a given supply pressure and flows are altered by restrictions. Regardless of what media is used ..regardless of what loading does to it ...the filter (typically) can never amount to much in the big scheme of things in the fluid circuit. It's a (again, typically) non-issue. Hence a filter, even heavily loaded, is not a "restrictions" per se~. Just like a rapids doesn't alter the flow of a river. Same gallons before the rapids ...same gallons out. What it does is accelerate the fluid to "fill in the variable in the equation". There's (again typically) no flow alteration in the normal oil fluid circuit ..any and all "restrictions" are merely evidenced in pressure elevations that express how the fluid had to accelerate. The mean velocity isn't (again, typically) altered at all, it just accelerates or decelerates for the relative size of the transmission conduit.

Since the engine is, by FAR, the biggest restriction that the oil flow is ever gonna see, the filter, assuming that there's no gross leakage at the oil pump, or that the viscosity is so high to engage the relief circuit, will always be some extremely small fraction of the total pressure DEVELOPMENT of any given flow. The engine will ALWAYS trump it (stated qualifications taken into account).

How is 5gpm of flow through a 1" pipe different from 5gpm flow through a 4" pipe? The "back pressure" generated and the velocity. Both are still 5gpm. Now put a .250 restrictor on the outlet of both pipes. Now how much do the pipe diameters mean when both 5gpm flows are traveling through a .250 outlet? Now the 1" pipe will have 16X (pulled out of my behind) the PRESSURE alteration of the 4" pipe ..but both will amount to NOTHING compared to the .250 restriction in the total scheme of things.

Nothing that I've stated here is altered by whether you've got synthetic media ...junk media ...or mediocre media. If you've got uniform depth media ...then your gonna have better filtration (allegedly) without as much of a upward curve in efficiency. That is, you don't have to wait for the larger pores to clog so that more of the oil flow will be channeled to the smaller pores (all pores get flow- the "share" is variable if you've got a broad variance in pore size).

Any filter presents a "resistance" ...but regardless of if it's high or low, it's on such a small scale that there is no such thing as a "restrictive" filter. The oil just has to travel faster through it. If a filter has a substantial differential (aside from gross loading) then you're seeing the differential of oil pump output ..vs..oil flow to the engine. It typically has nothing to do with the filter beyond a transitional state (in some engines) and has much to do with the oil pump being able to move a higher viscosity mass through the engine without reaching its relief limit. As the flows reach unity (the volume that the pump is putting out ..and what the engine can handle at that pressure limit ..that differential will evaporate. In many cases it's simply a matter of inertia. A static cold heavy oil mass just isn't able to accelerate instantly. Hence the oil pump "spins its tires" (loses traction to move all of the oil forward). Once the static mass "catches up" ..the "back pressure" eases ..and the oil pump output begins to match the flow to the engine. The filter just creates a dividing wall to realize this differential (for us to view the produced flow vs. the realized flow. This is the only time that a filter ever presents a true restriction (again all stated conditions taken into account) Your bypass valve limits the amount of this differential to some sensible level ..and therefore limits the divergence of flow. This would be a "transitional" state not to be taken at all as a common component in the scheme of things in regard to flow.

 

[GeorgeCLS]

Another way to look at a synthetic medium vs. cellulose. Roughly 40% of a cellulose filter flows nothing at all. Synthetic medium filters flow 100%, filter 100%. Bingo. Even with the much finer filtration, not rocket science to see how/why a synthetic filter will flow much easier and contain much (4 times generally) more contaminant than a comparably sized cellulose element.
George Morrison, STLE CLS

 

[mckennaiii]

Is the NAPA Gold oil filter and synthetic or cellulose?

 

[Gary Allan]

I imagine that it's a blend. It's listed as "paper" on the website. The synthetic media is listed a "glass" (micro-glass).

 

[glenncof]

From my reading, I do belive the load-up charateristic of the full synthetic filters can be good due to the fiberous depth (fuzzy) and maintain good, consistent pore size filteration. Study info from Donaldson on Syntec and Fleetguard on Stratapore media. The glass media is brittle so I often find a screen backing on pleats. I found Wix and FRAM (Extended Guard) both have a limited line of sythetic media filters. Synthetic does not necessarily mean small pore size though so check carefully.

Unless you have a diesel engine, cost/availability appear to be the main drawback. I would like to use one in my application but the cost is x3-4.