Diesel fuel filter for oil bypass filter?

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I would really like to put a bypass filter on my truck but I'm not remotely interested in a $60-80 filter element from Amsoil or others. Recently, I've seen some suggestions on using a diesel fuel filter as an oil bypass filter. There is even a guy all over ebay selling kits (for about 10 times their value) that utilizes a Baldwin BF7587 fuel filter rated at 4 micron. "Ebay guy" claims it works fine as an oil filter, but does it? I can't find any other info about this good or bad, other than a few people that say "it wasn't made for that"...these same people have also never tried.

Another filter that could potentially be used is the CAT 1R-0750, which is rated at 2 microns. Both are quite large filters, and really cheap to replace. As a bonus they increase oil capacity by a quart or two.

Is there anything wrong with this? The only issue I can see is oil gets hotter than diesel fuel, but diesel fuel can still get hot too. The 1-14 filter mounts for these are also really cheap.
 

wwillson

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That's an interesting proposal. I can't think of any reason it wouldn't work and you are correct that the elements are much less expensive.
 

dnewton3

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Those "ratings" are not informational at all; knowing a particle size without an efficiency is only half the info needed. I don't think it will hurt at all, but only experimentation will reveal the truth. Why not try it and report back your results? Run some UOAs prior to installation to understand your baseline, then several UOAs afterward to know the effects of the new system. Make sure you have a mount that includes a restriction orifice to slow the flow.
 
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The bypass oil filters while expensive last a long time. Some change them when the outside of the filter feels cool when the engine is warm.

I change mine at 4 clicks of the OLM. So roughly 32K miles.
 
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It may work, but the filter element on a fuel filter is made for... well fuel. Pushing a much denser fluid through a fuel filter (also designed for high flow) may not be a good idea for filter media integrity.
 

Chapter21

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The bypass oil filters while expensive last a long time. Some change them when the outside of the filter feels cool when the engine is warm.

I change mine at 4 clicks of the OLM. So roughly 32K miles.
So you're saying it wouldn't be better to have a bigger filter that lasts longer AND cost almost nothing to replace from any auto parts store? I'm not interested in any parts you can't find beside the freeway in the middle of nowhere. Also, adding a giant filter adds 2 quarts of oil to my capacity.

It may work, but the filter element on a fuel filter is made for... well fuel. Pushing a much denser fluid through a fuel filter (also designed for high flow) may not be a good idea for filter media integrity.
Except diesel fuel is...oil. When cold it can be very dense. With a small orifice just like you would use on a bypass filter limiting to around 1 quart/minute would that not increase the efficiency of the filter? It also wouldn't be under the same pressure as a normal filter since the output is not pressurized.

Like it or hate it there IS a guy on ebay selling these for this purpose, and he has sold many hundreds with 100% feedback. It just seems really weird to me nobody else has tried or ever posted any results that I can find. He is also ripping people off, he's just selling a $40 generic filter mount for $120...doesn't even include the filters. LOL!
 
Welcome to BITOG!
I'm not going to address your choice of filters, I'm going to address your attitude regarding money and bypass filtration. I don't think you should even attempt it, because to find out its effectiveness (or lack of it), you need to spend a few hundred dollars on used oil analysis. You'll need an analysis before you add any bypass filtration so you have a baseline. Then, once your filtration is on and in running condition, you'll need another UOA either at the end of your oil life monitor or when you regularly change oil. (Is it better or worse than before you started?)
I run bypass filtration and have been doing so for many tens of thousands of miles, but I'm not willing to risk my engine by not knowing what's going on with the condition of my oil; so you're going to need another oil analysis when you have enough miles that you can't stand it anymore and you think you should change it. Or should you? How well is your bypass filtration working? The only ones who can tell you are the test labs who do oil analysis, and you need particle counts with every oil analysis which is going to cost $20-$30 more than just analysis.
Not including the initial cost of the filter, mounting hardware and supply/return lines, you're GOING to spend a few hundred dollars on oil analysis to see how well your system is working and how "clean" your oil is per ISO 4406 particle counting; and to figure out your new (extended) oil change interval.
The size of this investment to objectively determine if you're actually doing any good doesn't sound to me like the same brain waves as the guy who doesn't want to spring for replacement filters. Save your money, time, trouble, headache, etc., and don't even start on it.
BTW, Dave Newton has stated very well above that without efficiency ratings, the information you've seen on micron ratings is useless. My screen door or barbeque grill will stop 2 micron particles also, just not very efficiently. Even a fram (rock catcher) el cheapo walmart oil fillter gives efficiency ratings on their website: https://www.fram.com/technical-info...mptions that more is,in a filter's media area. (95.7% at 20 microns)
Lest you think I am speaking about something I don't know, check out this thread where I am soundly criticized; go all the way to the end so you can see my responses and photos of my setup: https://bobistheoilguy.com/forums/threads/adding-an-engine-oil-bypass-filter-toughts.337936/
 
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So you're saying it wouldn't be better to have a bigger filter that lasts longer AND cost almost nothing to replace from any auto parts store? I'm not interested in any parts you can't find beside the freeway in the middle of nowhere. Also, adding a giant filter adds 2 quarts of oil to my capacity.


Except diesel fuel is...oil. When cold it can be very dense. With a small orifice just like you would use on a bypass filter limiting to around 1 quart/minute would that not increase the efficiency of the filter? It also wouldn't be under the same pressure as a normal filter since the output is not pressurized.

Like it or hate it there IS a guy on ebay selling these for this purpose, and he has sold many hundreds with 100% feedback. It just seems really weird to me nobody else has tried or ever posted any results that I can find. He is also ripping people off, he's just selling a $40 generic filter mount for $120...doesn't even include the filters. LOL!

I am thinking my bypass filter costs me about $20 a year. Given all the other costs of my F-250 PSD the $20 is insignificant.
 
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So you're saying it wouldn't be better to have a bigger filter that lasts longer AND cost almost nothing to replace from any auto parts store? I'm not interested in any parts you can't find beside the freeway in the middle of nowhere. Also, adding a giant filter adds 2 quarts of oil to my capacity.


Except diesel fuel is...oil. When cold it can be very dense. With a small orifice just like you would use on a bypass filter limiting to around 1 quart/minute would that not increase the efficiency of the filter? It also wouldn't be under the same pressure as a normal filter since the output is not pressurized.

Like it or hate it there IS a guy on ebay selling these for this purpose, and he has sold many hundreds with 100% feedback. It just seems really weird to me nobody else has tried or ever posted any results that I can find. He is also ripping people off, he's just selling a $40 generic filter mount for $120...doesn't even include the filters. LOL!
There are anti-gel additives to keep it from gelling (paraffin wax crystallization) over so it remains in a low viscosity state for fuel, even in the cold temperatures
 

Chapter21

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Welcome to BITOG!
I'm not going to address your choice of filters, I'm going to address your attitude regarding money and bypass filtration. I don't think you should even attempt it, because to find out its effectiveness (or lack of it), you need to spend a few hundred dollars on used oil analysis. You'll need an analysis before you add any bypass filtration so you have a baseline. Then, once your filtration is on and in running condition, you'll need another UOA either at the end of your oil life monitor or when you regularly change oil. (Is it better or worse than before you started?)
I run bypass filtration and have been doing so for many tens of thousands of miles, but I'm not willing to risk my engine by not knowing what's going on with the condition of my oil; so you're going to need another oil analysis when you have enough miles that you can't stand it anymore and you think you should change it. Or should you? How well is your bypass filtration working? The only ones who can tell you are the test labs who do oil analysis, and you need particle counts with every oil analysis which is going to cost $20-$30 more than just analysis.
Not including the initial cost of the filter, mounting hardware and supply/return lines, you're GOING to spend a few hundred dollars on oil analysis to see how well your system is working and how "clean" your oil is per ISO 4406 particle counting; and to figure out your new (extended) oil change interval.
The size of this investment to objectively determine if you're actually doing any good doesn't sound to me like the same brain waves as the guy who doesn't want to spring for replacement filters. Save your money, time, trouble, headache, etc., and don't even start on it.
BTW, Dave Newton has stated very well above that without efficiency ratings, the information you've seen on micron ratings is useless. My screen door or barbeque grill will stop 2 micron particles also, just not very efficiently. Even a fram (rock catcher) el cheapo walmart oil fillter gives efficiency ratings on their website: https://www.fram.com/technical-information/#:~:text=FRAM Extra Guard® is,microns using the ISO test.&text=Simple assumptions that more is,in a filter's media area. (95.7% at 20 microns)
Lest you think I am speaking about something I don't know, check out this thread where I am soundly criticized; go all the way to the end so you can see my responses and photos of my setup: https://bobistheoilguy.com/forums/threads/adding-an-engine-oil-bypass-filter-toughts.337936/

LOL! I will not be getting any UOA and I am not interested. No, that is not a requirement to use a bypass filter. Personally I think that is a dumb thing to do unless it's on a SUPER expensive machine with gallons of oil, but if you want to test yours knock yourself out. It's cheaper to just dump the oil and replace it every thousand miles than to do a UOA on a 1/2 ton pickup. There certainly is no risk of making anything worse by adding a bypass filter and it is definitely going to catch more things than the factory filter rated at around 30 micron. Can I quantify that in PPM? No, but I have no desire to, I don't plan on taking the truck to court. I very vaguely wonder if the filter could fall apart in this usage scenario, but without any supporting evidence that is pushing it. I'll probably test it first with a normal full flow oil filter after the bypass just incase the filter blows up. Filters can of course be easily cut apart to inspect the contents. And I can easily install the entire system for well under $100.

As for the questions about micron ratings, I trust CAT, and so do many others, let's just leave it at that. They are not going to sell bad filters for $250,000 machines. Diesel fuel needs to be much cleaner than oil, especially these days. And lets also please stay on topic, that would be lovely.
 
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Chapter21

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I am thinking my bypass filter costs me about $20 a year. Given all the other costs of my F-250 PSD the $20 is insignificant.
I thank god every day I don't have to maintain a powersmoke. I barely have to spend more than $20 a year for all maintenance on my truck, and if I installed a 2 quart or larger bypass filter it would probably last the life of the truck.
 
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Chapter21

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There are anti-gel additives to keep it from gelling (paraffin wax crystallization) over so it remains in a low viscosity state for fuel, even in the cold temperatures
You're missing the point. I do not have a diesel engine and it isn't being used for diesel fuel. It is however reasonable to consider that a diesel fuel filter may at some point in it's life experience thick oil. The packaging does not say "do not use in freezing temperatures unless you have used anti gel additives".
 
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dnewton3

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I think perhaps you should take a step back and help us understand what your quest is all about, OP.

There's really only two reasons to use BP filtration ...
- to greatly extend the OCIs, as a tool to improve the ROI for the overall lubricant maintenance system of your equipment
- as an ignorant exercise in futility, with no clear understanding other than a desire to make things "better" with zero definition of what "better" means
So ... What's your goal here?

The topic of BP filtration is really no different than most any other topic under the sun. You can either properly or improperly utilize something, and that often depends upon the conditions under which that topic will be applied. Taking something out of context is unlikely to lead to success, and even if one stumbles onto good results, it will be by chance and not due to deliberate act.

BP filters are a fantastic way to greatly extend the OCIs of any piece of equipment, but they are probably THE most understood tool in the toolbox of maintenance choices. Most people will get sucked into the BP filtration concept because they think (in error I'll add) that a BP filter will make for less wear in an engine, but they don't understand what conditions that may or may not be true. For several reasons, BP filters don't have the effect people believe them to, because of the intent of OCI duration.

The vast majority of misinformation regarding BP filters comes from the marketing garbage of most any BP filter maker which touts the infamous GM filter study from decades ago. That study is grossly misunderstood, and while not completely flawed, leads to terribly erroneous conclusions for the uninformed.

The reality is that BP filtration is not significantly effective at reducing wear in any way if a "normal" OCI is your intention. And the main reason this is true is because, while BP filter elements are very efficient at removing particles down to 3-4um with absolute results, the dirty little secret is that soot (the primary cause of wear generated from inside the engine) actually starts out about 100x smaller than that. Soot typically starts out around 40 nm in size, give or take a bit. It is pretty much impossible for a BP filter elements to affect soot-related wear in a normal OCI, because the soot has not yet amalgamated to a size where the filter element will have any efficiency at trapping it. What controls soot at such small sizes is the additive package in the oil; the anti-agglomerates and dispersants are what keep soot from keeping too large. Over the life of the OCI, there is eventually a point where the soot particles will co-join en-mass and then start to be an issue. But there are a massive slew of UOAs which show "normal" OCIs (out to 15k miles) have very desirable wear rates even without using BP filtration. And when UOAs are done in "normal" OCIs which have the claimed benefit of BP filtration, there's never any statistically significant proof that the BP filter element improved anything in terms of wear reduction.

The reason BP filters have the potential to be a good choice is because if you intend to run the OCI long enough, the soot control they offer can be hugely beneficial in really long oil runs. Once the additive package starts to be compromised (past 15k miles as my data indicates), THEN the BP filter element becomes a major player in the wear control, because the soot amalgamation is becoming much more prominent.

And, extended OCIs need to be monitored with UOAs, so that you know what's happening in the sump. You've already indicated you have zero intention of doing UOAs. You've also given no outward indication that you intend to do extended OCIs. So how will you know that this little experiment will work and give you the results you expect? You are correct in stating that getting UOAs is not a requirement to use BP filtration; that is true. But it IS a requirement to do UOAs if you actually want to understand how the BP is affecting the oil, and when to change oil, while using a BP filter such that you actually get a good ROI from it.

If you operate under these assumptions:
- no extended OCIs
- no UOAs will be done
- no PCs will be done
- adding the expense of BP filter system
I will assure you of two things:
1) you'll get no tangible reduction of engine wear
2) your ROI improvement will be completely imagined and never truly materialize

Now, if you're Hades-bent on doing this anyway (and it seems you are), then what was your quest here in the first place? This thread is your first conversation with BITOG, and you're already willing to ignore all the logical questions and comments. Did you come here for advice, or to espouse that you've discovered a golden nugget of lube intel that the entire rest of the BITOG community somehow didn't ever know about..

In your initial post, you asked "Is there anything wrong with this?"
Yes - your entire concept is flawed. Not because of the particular product you intend to choose, but your entire misunderstanding of what BP filtration can and cannot do relative to the environment it's placed into.

PS - the fact that you blew off the topic of efficiency vs particle size is yet another indicator you have no idea what you're doing, but that's another entire discussion.
 

AP9

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An interesting idea, but there are a few critical points to consider.

That fuel filter is intended for a CAT C15, which if memory serves me correctly has a maximum rated fuel flow rate of around 10 L/minute. But this is at low pressure (<4 bar) or even suction. That may or may not be sufficient for your intended application's oil flow rate, but the flow rate alone doesn't tell the whole story....

As for density, the diesel fuel will be a little bit less dense but not much. Viscosity, however, will be much higher with lubricating oil, regardless of temperature. That will drastically increase your pressure drop across the filter, which will (all else equal) increase roughly exponentially as your volumetric flow rate increases. That pressure differential across the filter likely will end up being higher than the filter was designed for.

Compound that with the fact that the lubricating oil will reach higher temperatures than the diesel fuel (which would seldom if ever reach 90°C on the supply side) and, restricting orifice or not, you could be setting yourself up for filter collapse.

Also keep in mind that the SAE J1985 initial single-pass efficiency rating is a test method for fuel filters, not lubricating oil filters.

With respect to the merits, value, etc. of the whole idea of bypass filtration to begin with, please consider the points that dnewton3 and Ihatetochangeoil have addressed.
 
The topic of bypass filters is interesting and I take it people are using the engines’s oil pressure to push the oil through the filter in a parallel channel, hence the name bypass. The amount of flow through the bypass filter is a function of the pressure drop across the filter relative to the pressure drop across the parallel pathway, which is the engine’s normal pathway through the oil filter and galleries. The kinematic viscosity of diesel measured at 40 degrees C is from 1 to 4 cSt ( 1 mm2/s = 1 cSt). The kinematic viscosity of motor oil measured at 100 C is approximately 7 to 14 cSt across the range of xw20 to xW40, so basically the viscosity of oil is about four times that of diesel at the temperatures they are normally at ( give or take). A person would have to do a C&P on a diesel filter and compare the “paper element” to an oil filter. The diesel filter would also have the much large cross section to lower the pressure drop. Here is some stuff on the viscosity of diesel.

96776E6B-5788-474D-86F3-F2025648FAFB.png
 

dnewton3

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IMO, from a very simplistic outside view, if the makers of filters could market their fuel filters as lube filters, they'd already be doing it. They are separate products for good reason; the application engineering details dictate different products.
 

Chapter21

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IMO, from a very simplistic outside view, if the makers of filters could market their fuel filters as lube filters, they'd already be doing it. They are separate products for good reason; the application engineering details dictate different products.
They can't sell them as lube oil filters because they are not full flow filters and nobody ever asked about those...and no, of course it would not have the same flow. That is literally the only reason standard oil filters are ~30 micron while bypass filters are in the neighborhood of 2. Also they are enormous holding 2-5 quarts of oil, they won't fit in most cars.

I can see most here just want to argue and be an expert even though they've never even touched the filters I'm talking about, so I'm not going to bother posting about it any longer. I realize you are oil nerds, but that does not mean one needs to be one or care to be one to use or desire a bypass filter. Furthermore, I will not purchase any product from Amsoil, and I'm certainly not using toilet paper. Are you telling me the only suitable single micron oil filters in the world with a simple screw on can design are made by Amsoil? Something wrong with that statement.

I have specifically left out the details of my engine or oil system because I'm not asking any questions about that, I'm only talking about filters and the question is the same no matter what engine I might use it on. In fact the exact same thing applies to transmissions as well. I'm not stupid, I know how bypass filters work and their purpose, stop assuming that just because somebody doesn't spend their life on an oil forum that they are newbie to lubrication specialties. I am fully aware that diesel fuel and lubricating oil are in fact different fluids. :gasp: They also happen to be very similar in a lot of ways. (A diesel engine will run on straight 15w40, for example!)

Even if it had no filtration effect what so ever you're totally ignoring the fact that I will roughly double my oil capacity. I would literally buy a giant 4 quart empty CAT can if somebody sells them. And it's better than adding a deeper oil pan, because it can be thermostatically controlled as well mounted somewhere less likely to be punctured.

Also, there's this issue of the guy on ebay with many hundreds/thousands of sales at 100% feedback rating, there must be something to this. He isn't even chinese. Wouldn't you think if somebody had sold thousands for this purpose on the internet we would see some internet forum posts about them popping if that's what happens? Even if I go beyond a search and ask self appointed experts like I did, no examples appear. Odd really nothing good or bad to be found. They are mostly targeted at diesel ford boys, and their two favorite things are bragging and complaining.

I'm going to buy both a Baldwin and CAT filter, two each, cut them open, and run them in hot oil, and cut them open again to find the answer. There are really only 2 questions: will the filter hold together at higher temps, and will it hold together with thicker oil. The answer can only be yes or no, there is no gray area. There is no risk to the engine at all if a typical full flow lube filter is added after the test filter. (if the filter blows it would catch any debris) Additionally, for those going on about cost, you need to wrap your head around the fact that I can buy multiple filters, filter mounts, and the plumbing I require for about $50. In a time of shortages. The price on the filters has actually gone down since I asked this question, and I can get mounts for $5.

If you want to use an Amsoil filter, that's great, have fun. I won't hold it against you. Personally I hate Coca-Cola but I don't yell at the people in the grocery store buying it when I go for the Mtn Dew.
 
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