Oil Bath Air Cleaner

We install a modern paper filter element in oil bath air cleaners. It certainly does away with the oily mess, and gives filtration equal to that of modern cars. We did a sheet on it years ago. I'll try to find and post it if you want it. The attachment process on this site is certainly cumbersome, and I still haven't mastered it yet. If oil bath air cleaners were more efficient than paper, there would be no paper. Henry Ford had no love for filters. The air horn on the Model A's faced rearward, as he believed that the heavy dust from the roads of the time would pass by the intake as the vehicle moved forward.
 
Hi Bob (Supereal)
Back in 2008 you had a post on EFV8 concerning the change from oil bath to a paper filter. You e-mailed me pictures and instructions on the procedures. It looked interesting so I bought the proper filter and started the project. Stopped when I realized that uncrimping the top from body was irreversible. So the paper filter is still in my stash. My 46 is very original and I decided to change as few things as possible. I still think that a properly maintained oil filter will not cause any extra wear (compared to a paper filter) on the bearing surfaces and that the change is unnecessary. JMhumbleO

John
 
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I have both for my 53' Merc. I used a Plasma cutter to cut the mesh out (it caught on fire - no surprise due to the oil in the mesh, so keep a fire extinguisher handy) The filter is a K&N E-1290. I find they both seem to work equally as to air flow. Since it is a K&N filter the bottom line is that it still uses oil for filtration.

Goal was to make one with a filter that looked origional.
 

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Yes, I know that. If air went through the oil, you'd have a real mess... :eek:

I know the flatheads don't but in my Farmall , the air does actually go thru the oil. As it sucks the oil up the canister it gets trapped in a wire mesh and falls back to the cup carrying the dirt with it. It took me a while to grasp the oil level being higher than the inlet to the oil cup but the filtration in that setup has to be outstanding.
 
I'm new to the early V8's so please be patient with my stupid questions...

I have a 53 Mainline with a stock 239 and want to swap from the little chrome air cleaner back to the original oil bath. My brother happened to have one off his old flathead from years ago that is in very good shape.

I was wondering if people who use the oil bath are actually using oil in them or if they are running dry? I want to know more about the oil bath...any information would be helpful!

Thanks!
Kevin

I am using my oil bath air cleaner as Henry designed it. I know it has oil in it so I am careful not to spill it. All of this "redesigning" is nothing more than make work. I doubt it helps one bit, if at all.
 
I know the flatheads don't but in my Farmall , the air does actually go thru the oil. As it sucks the oil up the canister it gets trapped in a wire mesh and falls back to the cup carrying the dirt with it. It took me a while to grasp the oil level being higher than the inlet to the oil cup but the filtration in that setup has to be outstanding.
Yes, the air is drawn through the oil, the oil circulates, the mesh in a properly serviced filter is self cleaning by this oil, most likely the oil bath is not as restrictave as a paper filter, and the restriction stays the same unlike a paper filter that gets more restrictive as it gathers dirt ---the oil bath fell out of favor because it needed service, the paper filter was a "improvement" in parts profit and labor needed to service it (idiot could change it without worring about oil level

running the "oil bath" dry could cause it to clog up, the oil circulating in the filter cleans the mesh, cleaning the oil bath means cleaning all the grunge out of the oil sump, and filling the oil to the proper level
 
We converted oil bath air cleaners to paper elements a long time ago. I still have the instruction sheet if anyone wants it. You do have to pry up the edges of the lid to install a metal disk in the top, but if you are careful, the original "top hat" can be reinstalled, if desired by prying up the edges again, than re crimping. Once you convert, unless you are a purist, I would stay with the modern element. The only engines that still use an oilbath filter are mostly offroad equipment and large trucks. Those use a "whirlwind" to allow the oil to catch the dirt, where the old type depended on the inertia of the particles to cross the surface of the oil pool, which was not as efficient.
 
Yes, the air is drawn through the oil, the oil circulates, the mesh in a properly serviced filter is self cleaning by this oil, most likely the oil bath is not as restrictave as a paper filter, and the restriction stays the same unlike a paper filter that gets more restrictive as it gathers dirt ---the oil bath fell out of favor because it needed service, the paper filter was a "improvement" in parts profit and labor needed to service it (idiot could change it without worring about oil level

running the "oil bath" dry could cause it to clog up, the oil circulating in the filter cleans the mesh, cleaning the oil bath means cleaning all the grunge out of the oil sump, and filling the oil to the proper level

The oil circulates in an oil bath filter??? What are you smoking Kurt?
 
We converted oil bath air cleaners to paper elements a long time ago. I still have the instruction sheet if anyone wants it. You do have to pry up the edges of the lid to install a metal disk in the top, but if you are careful, the original "top hat" can be reinstalled, if desired by prying up the edges again, than re crimping. Once you convert, unless you are a purist, I would stay with the modern element. The only engines that still use an oilbath filter are mostly offroad equipment and large trucks. Those use a "whirlwind" to allow the oil to catch the dirt, where the old type depended on the inertia of the particles to cross the surface of the oil pool, which was not as efficient.


Thank you for the reply. I wondered if it could be done...now I know!
 
The oil circulates in an oil bath filter??? What are you smoking Kurt?

Whatever I smoke(If I was to smoke) doesn't interfere with fact, i have watched a cutaway filter with a window in it in operation, to back it up i googled it and found a research paper ---look at page 6, and 10
http://deepblue.lib.umich.edu/bitstream/handle/2027.42/4003/bab9801.0001.001.pdf?sequence=5

if you want to prove it wash the element dry, just fill the oil to the proper level and go for a drive ----I have done this too, the filtering mesh gets oiled, the design is such that excess oil drains back, carring dirt with it
 
Does the mash in a oil type filter have to be cleaned with gasoline or some other type solvent on some type of schedule?
 
Whatever I smoke(If I was to smoke) doesn't interfere with fact, i have watched a cutaway filter with a window in it in operation, to back it up i googled it and found a research paper ---look at page 6, and 10
http://deepblue.lib.umich.edu/bitstream/handle/2027.42/4003/bab9801.0001.001.pdf?sequence=5

if you want to prove it wash the element dry, just fill the oil to the proper level and go for a drive ----I have done this too, the filtering mesh gets oiled, the design is such that excess oil drains back, carring dirt with it
Interesting paper, just wonder if this 1956 study had the present day dry elements to compare to, which would be more efficient?
 
The oil circulates in an oil bath filter??? What are you smoking Kurt?

It has to "circulate" as when the engine is stopped the oil in the cup is higher than the intake pipe. The only way for the air to get to the engine is to go thru the oil and pull it along with it , as the oil gets trapped on the mesh it fall back in the cup. It doesn't seem right but that's how it works.
 
The incommong air puts a wave action on the oil causing it to percolate up into the metal mesh with the aid of the baffle. The air just passes through the oily mesh. The oil lightly percolates up into the mesh as long as air is flowing. No filter removes all contaminants but the oil bath is efficient enough. Cleaning them is a chore since most of the dirty air drawn into the thing has a fine talc along with that is very difficult to flush out. I just scrape the stuff out after washing most of the oil residue off. Paper filters are definitely easier to service. Give it a fling and install a new one. No muss no fuss. The military still uses a lot of oil bath type filters due to supply concerns. Rather than stock a bunch of filters, all they have to stock is something they already use, motor oil. Now getting the troopies to clean the filters out properly is a another problem. We had them on the generator sets, air compressors, and a whole list of other motorized equipment. If the operators didn't clean them then soon there was no room for oil anymore.
 
Does the mash in a oil type filter have to be cleaned with gasoline or some other type solvent on some type of schedule?

I was always told to soak them in kerosene and it seems to work rather well. I service a car that claimed to have vaporlock issues but turns out his oil bath filter was so clogged that it was causing the engine to run rich. As soon as he shut off the car it would be flooded and take a bit to get it to start again if hot.
 
Yes, oil drawn into mesh by slow and dripping back down is certainly part of the system.
The oily mesh traps the lighter particles and drips most of them back down with the oil after the heavy stuff is carried by its momentum straight down into the sump.
Ford mentioned in bulletins that the normal hat type oil baths will hold about a pound of crud, the big offset heavy duty ones three pounds!
A long soaking of the mesh is important on old ones...if they were run too long with dirty oil the mesh could become blocked with petrified oily crud, making the thing restrictive and inefficient in all ways. With most designs the mesh can be hung down into solvent with the painted top safely out of the soup.
 
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