I started asking and found no one who could give an answer, is a oil bath air filter more efficient than a paper filter. I have a 47 dodge light duty truck that came with an oil bath filter and wanted to know if changing over to a paper filter would be better for the engine in the long run.
Oil bath air filter
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If oil bath air filters were better technology, do you think car companies would have moved away from them en masse for paper filter technology?
If paper air filters were better technology, do you think car companies would move away from oil bath filters en masse?
These questions answer themselves. From a mass production perspective, the choice is obvious.
If paper air filters were better technology, do you think car companies would move away from oil bath filters en masse?
These questions answer themselves. From a mass production perspective, the choice is obvious.
wemay
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Originally Posted By: Imp4
If oil bath air filters were better technology, do you think car companies would have moved away from them en masse for paper filter technology?
If paper air filters were better technology, do you think car companies would move away from oil bath filters en masse?
These questions answer themselves. From a mass production perspective, the choice is obvious.
Not necessarily so. The decision to go with paper may have come down to ease of maintenance as top priority.
If oil bath air filters were better technology, do you think car companies would have moved away from them en masse for paper filter technology?
If paper air filters were better technology, do you think car companies would move away from oil bath filters en masse?
These questions answer themselves. From a mass production perspective, the choice is obvious.
Not necessarily so. The decision to go with paper may have come down to ease of maintenance as top priority.
Originally Posted By: Wemay
Not necessarily so. The decision to go with paper may have come down to ease of maintenance as top priority.
If so, there would be an array of boutique (K&N, etc) that would offer these to the current market. My quick Googly search hit on Wikipedia 1st. Never a good sign if you are marketing a product.
In other words, noboby worth discussing sells them. No, they are not better. Full stop.
Not necessarily so. The decision to go with paper may have come down to ease of maintenance as top priority.
If so, there would be an array of boutique (K&N, etc) that would offer these to the current market. My quick Googly search hit on Wikipedia 1st. Never a good sign if you are marketing a product.
In other words, noboby worth discussing sells them. No, they are not better. Full stop.
Originally Posted By: Imp4
If oil bath air filters were better technology, do you think car companies would have moved away from them en masse for paper filter technology? ...
That they made that move certainly doesn't in itself prove paper necessarily filters better. Paper filters and associated housings have several other advantages. They're lighter, cheaper to manufacture, easier to maintain, less messy, more profitable in parts sales, and insensitive to orientation. If they also filter better, that's another plus, but even if they only equaled oil-bath filters on that count, manufacturers had ample motivation to switch. During the transition, some manufacturers offered oil-bath filters as an option over paper (or oiled foam).
If oil bath air filters were better technology, do you think car companies would have moved away from them en masse for paper filter technology? ...
That they made that move certainly doesn't in itself prove paper necessarily filters better. Paper filters and associated housings have several other advantages. They're lighter, cheaper to manufacture, easier to maintain, less messy, more profitable in parts sales, and insensitive to orientation. If they also filter better, that's another plus, but even if they only equaled oil-bath filters on that count, manufacturers had ample motivation to switch. During the transition, some manufacturers offered oil-bath filters as an option over paper (or oiled foam).
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Originally Posted By: CR94
During the transition, some manufacturers offered oil-bath filters as an option over paper (or oiled foam).
This is true, but irrelevant with respect to design/technology superiority.
Most manufacturers offer legacy options during a transition unless it is a safety issue or because of a lack of legacy inventory.
During the transition, some manufacturers offered oil-bath filters as an option over paper (or oiled foam).
This is true, but irrelevant with respect to design/technology superiority.
Most manufacturers offer legacy options during a transition unless it is a safety issue or because of a lack of legacy inventory.
Originally Posted By: CR94
They're lighter, cheaper to manufacture, easier to maintain, less messy, more profitable in parts sales, and insensitive to orientation. If they also filter better, that's another plus
Thank you for these 6+ additional reasons paper filters are superior.
They're lighter, cheaper to manufacture, easier to maintain, less messy, more profitable in parts sales, and insensitive to orientation. If they also filter better, that's another plus
Thank you for these 6+ additional reasons paper filters are superior.
One side note; oil bath air filters performed much better during the Mt Saint Helens eruptions. Easy to clean and refresh with SAE 30wt. Paper air filters clogged immediately and the micro shards of the ash poked holes in the media. Countless thousands of engines were ruined during those times. Air filters were scarce and parts stores couldn’t keep them in stock.
Originally Posted By: PimTac
One side note; oil bath air filters performed much better during the Mt Saint Helens eruptions. Easy to clean and refresh with SAE 30wt. Paper air filters clogged immediately and the micro shards of the ash poked holes in the media. Countless thousands of engines were ruined during those times. Air filters were scarce and parts stores couldn’t keep them in stock.
BITOG would crash if something like that happened today.
One side note; oil bath air filters performed much better during the Mt Saint Helens eruptions. Easy to clean and refresh with SAE 30wt. Paper air filters clogged immediately and the micro shards of the ash poked holes in the media. Countless thousands of engines were ruined during those times. Air filters were scarce and parts stores couldn’t keep them in stock.
BITOG would crash if something like that happened today.
Originally Posted By: preaction
I started asking and found no one who could give an answer, is a oil bath air filter more efficient than a paper filter. I have a 47 dodge light duty truck that came with an oil bath filter and wanted to know if changing over to a paper filter would be better for the engine in the long run.
Nope, a well designed oil bath will keep the intake clean and capture a lot of debris. Plus, it's serviceable at home, so you save $$. They got rid of them because air flow demands went way up with big motors and they are tough to fit under low hoods. But an old in-line 6 with a smallish carb is the perfect place for a good oil bath
I started asking and found no one who could give an answer, is a oil bath air filter more efficient than a paper filter. I have a 47 dodge light duty truck that came with an oil bath filter and wanted to know if changing over to a paper filter would be better for the engine in the long run.
Nope, a well designed oil bath will keep the intake clean and capture a lot of debris. Plus, it's serviceable at home, so you save $$. They got rid of them because air flow demands went way up with big motors and they are tough to fit under low hoods. But an old in-line 6 with a smallish carb is the perfect place for a good oil bath
Originally Posted By: Imp4
Originally Posted By: Wemay
Not necessarily so. The decision to go with paper may have come down to ease of maintenance as top priority.
If so, there would be an array of boutique (K&N, etc) that would offer these to the current market. My quick Googly search hit on Wikipedia 1st. Never a good sign if you are marketing a product.
In other words, noboby worth discussing sells them. No, they are not better. Full stop.
Gee, that's funny. They are very few tractors out in the fields with paper filters. They run in clouds of dust and most all run oil baths, with a cyclonic pre-filter.
Oil baths take vertical space by design. They would not fit under the hood of most 1960's cars with V-8's and A/C. Just no room. Once the trends started, it was a general move to ring style paper filters only a few inches tall.
K&N are a quasi oil bath (wet media, washable) filter.
A true oil bath big enough to feed my 5.8L V8 truck would be a foot in diameter and more than a foot long. Where would you put it under the hood ...
On my last Peterbuilt, the filter was oil bath and it was about 3 feet high and a foot in diameter. Buddies Pete 3-axle dump truck just came out of quarry service, twin oil baths hanging outside the hood - one on each side.
On trucks and tractors with in-line engines where there is no lack of space, they are still there doing their job.
Originally Posted By: Wemay
Not necessarily so. The decision to go with paper may have come down to ease of maintenance as top priority.
If so, there would be an array of boutique (K&N, etc) that would offer these to the current market. My quick Googly search hit on Wikipedia 1st. Never a good sign if you are marketing a product.
In other words, noboby worth discussing sells them. No, they are not better. Full stop.
Gee, that's funny. They are very few tractors out in the fields with paper filters. They run in clouds of dust and most all run oil baths, with a cyclonic pre-filter.
Oil baths take vertical space by design. They would not fit under the hood of most 1960's cars with V-8's and A/C. Just no room. Once the trends started, it was a general move to ring style paper filters only a few inches tall.
K&N are a quasi oil bath (wet media, washable) filter.
A true oil bath big enough to feed my 5.8L V8 truck would be a foot in diameter and more than a foot long. Where would you put it under the hood ...
On my last Peterbuilt, the filter was oil bath and it was about 3 feet high and a foot in diameter. Buddies Pete 3-axle dump truck just came out of quarry service, twin oil baths hanging outside the hood - one on each side.
On trucks and tractors with in-line engines where there is no lack of space, they are still there doing their job.
The option to oil bath at the time was no filter (motorcycles) or basically an oil bath with no oil bath, just the coarse mesh with no oil. Paper is just a win win. If an oil bath was reinvented we wouldn't have K&N threads anymore, there would be people complaining because their MAF is covered in oil...because they over filled the oil bath...and got their hands dirty.
Working on generators for ocean going reefer containers I found that while oil bath air cleaners were very efficient, they waste a lot of oil servicing the things and when you finally break them down for a real good cleaning a lot of varsol gets wrecked in the process. Never made sense to me.
I have three SAE papers from various eras that list the maximum efficiency of the average oil bath air filter at 80-85%. One from the 1920s touted 50% efficiency!Some of the cyclonic filters in tractors (HUGE) got over 90 percent. At the time oil bath filters were replaced industrywide, cellulose were upwards of 95% efficient. Contrast both of those with the bottom dollar minimum standard of today, which is around 97% and many filters do much better... up to 99%. When you factor in how much air an engine ingests over many thousands of miles and then you pile up how much the filter caught next to how much got thru to the engine, even a difference from 97 to 99 percent makes a noticeable pile. Consider the difference between 85% and 97%! I've seen those piles in the test labs of Fram and K&N and they are part of what gave me the "gospel" about filter efficiency. If it wasn't such a PITA to post images here, I have a couple of pile shots.
The other thing about oil baths, if you let the oil get down just a few millimeters, efficiency drops like a rock. Let it get muddy... efficiency drops like a rock. That's why they recommended DAILY air filter service in some cases. The harder you run the engine, the faster the oil level drops. Oil bath filters was one reason it was nearly a miracle for an engine to last 100K miles back in the day when your truck was built. On top of all that, they don't flow for [censored]!
Years ago, when I was writing for a Land Rover magazine (LRO), I took a bunch of carbs, filters and such to the K&N lab to be airflow tested on their flowbench. That batch of stuff included a Land Rover oil bath air filter. I was shocked (but not surprised) to see how much restriction it delivered. It literally didn't have the airflow needed to allow the engine to generate rated power. That says something about the old gross (no filter) vs modern net (with filter) ratings, but I digress. We discovered that by dropping the oil level, airflow increased, but efficiency dropped. Anyway, that explaned why a Land Rover 2.25L got a noticeable boost in mid range and upper end power by installing a modern filter.
What does the once in a several-hundred-thousand years eruption of a volcano have to do with day to day use?
For a restored collector rig, obviously the oil bath is there to stay and if it's operated sparingly in a good environment, a change is uneccesary. You will be dead of old age long before wear becomes an issue. If yours is something like a '47 WDX Power Wagon that hits the dirt regularly, adapting a paper air cleaner is a good idea. I did so on my late/great M-37 Dodge, which I wheeled the poop out of. You could build a filter that didn't alter the basically stock engine and for shows, install the oil bath for the period look. But a couple thousand miles a year on nice days around town, a typical collector rig, not worth the effort IMO.
The other thing about oil baths, if you let the oil get down just a few millimeters, efficiency drops like a rock. Let it get muddy... efficiency drops like a rock. That's why they recommended DAILY air filter service in some cases. The harder you run the engine, the faster the oil level drops. Oil bath filters was one reason it was nearly a miracle for an engine to last 100K miles back in the day when your truck was built. On top of all that, they don't flow for [censored]!
Years ago, when I was writing for a Land Rover magazine (LRO), I took a bunch of carbs, filters and such to the K&N lab to be airflow tested on their flowbench. That batch of stuff included a Land Rover oil bath air filter. I was shocked (but not surprised) to see how much restriction it delivered. It literally didn't have the airflow needed to allow the engine to generate rated power. That says something about the old gross (no filter) vs modern net (with filter) ratings, but I digress. We discovered that by dropping the oil level, airflow increased, but efficiency dropped. Anyway, that explaned why a Land Rover 2.25L got a noticeable boost in mid range and upper end power by installing a modern filter.
What does the once in a several-hundred-thousand years eruption of a volcano have to do with day to day use?
For a restored collector rig, obviously the oil bath is there to stay and if it's operated sparingly in a good environment, a change is uneccesary. You will be dead of old age long before wear becomes an issue. If yours is something like a '47 WDX Power Wagon that hits the dirt regularly, adapting a paper air cleaner is a good idea. I did so on my late/great M-37 Dodge, which I wheeled the poop out of. You could build a filter that didn't alter the basically stock engine and for shows, install the oil bath for the period look. But a couple thousand miles a year on nice days around town, a typical collector rig, not worth the effort IMO.
I stay away from oil bath filters. If I can’t find a AFE Pro Dry i run oem filters.
Thanks Jim for the input. I definitely want a paper air filter because of the increase in efficiency. Ed
wemay
Site Donor 2023
Originally Posted By: Jim Allen
I have three SAE papers from various eras that list the maximum efficiency of the average oil bath air filter at 80-85%. One from the 1920s touted 50% efficiency!Some of the cyclonic filters in tractors (HUGE) got over 90 percent. At the time oil bath filters were replaced industrywide, cellulose were upwards of 95% efficient. Contrast both of those with the bottom dollar minimum standard of today, which is around 97% and many filters do much better... up to 99%. When you factor in how much air an engine ingests over many thousands of miles and then you pile up how much the filter caught next to how much got thru to the engine, even a difference from 97 to 99 percent makes a noticeable pile. Consider the difference between 85% and 97%! I've seen those piles in the test labs of Fram and K&N and they are part of what gave me the "gospel" about filter efficiency. If it wasn't such a PITA to post images here, I have a couple of pile shots.
The other thing about oil baths, if you let the oil get down just a few millimeters, efficiency drops like a rock. Let it get muddy... efficiency drops like a rock. That's why they recommended DAILY air filter service in some cases. The harder you run the engine, the faster the oil level drops. Oil bath filters was one reason it was nearly a miracle for an engine to last 100K miles back in the day when your truck was built. On top of all that, they don't flow for [censored]!
Years ago, when I was writing for a Land Rover magazine (LRO), I took a bunch of carbs, filters and such to the K&N lab to be airflow tested on their flowbench. That batch of stuff included a Land Rover oil bath air filter. I was shocked (but not surprised) to see how much restriction it delivered. It literally didn't have the airflow needed to allow the engine to generate rated power. That says something about the old gross (no filter) vs modern net (with filter) ratings, but I digress. We discovered that by dropping the oil level, airflow increased, but efficiency dropped. Anyway, that explaned why a Land Rover 2.25L got a noticeable boost in mid range and upper end power by installing a modern filter.
What does the once in a several-hundred-thousand years eruption of a volcano have to do with day to day use?
For a restored collector rig, obviously the oil bath is there to stay and if it's operated sparingly in a good environment, a change is uneccesary. You will be dead of old age long before wear becomes an issue. If yours is something like a '47 WDX Power Wagon that hits the dirt regularly, adapting a paper air cleaner is a good idea. I did so on my late/great M-37 Dodge, which I wheeled the poop out of. You could build a filter that didn't alter the basically stock engine and for shows, install the oil bath for the period look. But a couple thousand miles a year on nice days around town, a typical collector rig, not worth the effort IMO.
Thanks for sharing.
I have three SAE papers from various eras that list the maximum efficiency of the average oil bath air filter at 80-85%. One from the 1920s touted 50% efficiency!Some of the cyclonic filters in tractors (HUGE) got over 90 percent. At the time oil bath filters were replaced industrywide, cellulose were upwards of 95% efficient. Contrast both of those with the bottom dollar minimum standard of today, which is around 97% and many filters do much better... up to 99%. When you factor in how much air an engine ingests over many thousands of miles and then you pile up how much the filter caught next to how much got thru to the engine, even a difference from 97 to 99 percent makes a noticeable pile. Consider the difference between 85% and 97%! I've seen those piles in the test labs of Fram and K&N and they are part of what gave me the "gospel" about filter efficiency. If it wasn't such a PITA to post images here, I have a couple of pile shots.
The other thing about oil baths, if you let the oil get down just a few millimeters, efficiency drops like a rock. Let it get muddy... efficiency drops like a rock. That's why they recommended DAILY air filter service in some cases. The harder you run the engine, the faster the oil level drops. Oil bath filters was one reason it was nearly a miracle for an engine to last 100K miles back in the day when your truck was built. On top of all that, they don't flow for [censored]!
Years ago, when I was writing for a Land Rover magazine (LRO), I took a bunch of carbs, filters and such to the K&N lab to be airflow tested on their flowbench. That batch of stuff included a Land Rover oil bath air filter. I was shocked (but not surprised) to see how much restriction it delivered. It literally didn't have the airflow needed to allow the engine to generate rated power. That says something about the old gross (no filter) vs modern net (with filter) ratings, but I digress. We discovered that by dropping the oil level, airflow increased, but efficiency dropped. Anyway, that explaned why a Land Rover 2.25L got a noticeable boost in mid range and upper end power by installing a modern filter.
What does the once in a several-hundred-thousand years eruption of a volcano have to do with day to day use?
For a restored collector rig, obviously the oil bath is there to stay and if it's operated sparingly in a good environment, a change is uneccesary. You will be dead of old age long before wear becomes an issue. If yours is something like a '47 WDX Power Wagon that hits the dirt regularly, adapting a paper air cleaner is a good idea. I did so on my late/great M-37 Dodge, which I wheeled the poop out of. You could build a filter that didn't alter the basically stock engine and for shows, install the oil bath for the period look. But a couple thousand miles a year on nice days around town, a typical collector rig, not worth the effort IMO.
Thanks for sharing.
Originally Posted By: BrocLuno
Gee, that's funny. They are very few tractors out in the fields with paper filters. They run in clouds of dust and most all run oil baths, with a cyclonic pre-filter.
Oil baths take vertical space by design. They would not fit under the hood of most 1960's cars with V-8's and A/C. Just no room. Once the trends started, it was a general move to ring style paper filters only a few inches tall.
K&N are a quasi oil bath (wet media, washable) filter.
A true oil bath big enough to feed my 5.8L V8 truck would be a foot in diameter and more than a foot long. Where would you put it under the hood ...
On my last Peterbuilt, the filter was oil bath and it was about 3 feet high and a foot in diameter. Buddies Pete 3-axle dump truck just came out of quarry service, twin oil baths hanging outside the hood - one on each side.
On trucks and tractors with in-line engines where there is no lack of space, they are still there doing their job
I can't think of any recent diesel tractor or truck with an oil bath air filter. I'm a farmer with two older tractors (one a 1970) and they are all paper. I was just into a 2010 CaseIH tractor an it was paper. Plenty of industrial stuff back in the day had oil bath with cyclonic features that put them into the 90% area. Name me anything recently built with an oil bath air filter? If this is some kinda new trend that slipped by me, I'd like to learn more about that.
Gee, that's funny. They are very few tractors out in the fields with paper filters. They run in clouds of dust and most all run oil baths, with a cyclonic pre-filter.
Oil baths take vertical space by design. They would not fit under the hood of most 1960's cars with V-8's and A/C. Just no room. Once the trends started, it was a general move to ring style paper filters only a few inches tall.
K&N are a quasi oil bath (wet media, washable) filter.
A true oil bath big enough to feed my 5.8L V8 truck would be a foot in diameter and more than a foot long. Where would you put it under the hood ...
On my last Peterbuilt, the filter was oil bath and it was about 3 feet high and a foot in diameter. Buddies Pete 3-axle dump truck just came out of quarry service, twin oil baths hanging outside the hood - one on each side.
On trucks and tractors with in-line engines where there is no lack of space, they are still there doing their job
I can't think of any recent diesel tractor or truck with an oil bath air filter. I'm a farmer with two older tractors (one a 1970) and they are all paper. I was just into a 2010 CaseIH tractor an it was paper. Plenty of industrial stuff back in the day had oil bath with cyclonic features that put them into the 90% area. Name me anything recently built with an oil bath air filter? If this is some kinda new trend that slipped by me, I'd like to learn more about that.
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I dunno about new. Have not bought a new piece of equipment in 40 years ...
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