oil bath filters (like from the 60's)

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233
Location
Minnesota
Turning back the clock half a decade... would oil bath air filters have ANY usability in the modern world on a modern vehicle, despite the maintenance hassle? I've been reading up on them a bit later just out of curiosity, with my understanding being that they didn't necessarily filter small particulates as well as modern paper filters, but have potentially even better efficiency for larger particles. (how much different particle sizes affect wear i'm not sure) My understanding is they are still used on certain farm tractors and industrial equipment especially in very dusty conditions. Yet can sometimes need DAILY servicing in those conditions. Though i'm wondering if paper filters would last even shorter under those conditions - ie will oil bath filters actually last LONGER between service intervals, despite the ease of a 30 second air filter swap being far more convenient?
 
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2,408
Location
CA
The ducting of the air tubes in a lot of the modern vehicle works in the same way to fling particles out of the way before it gets to the filter with an escape or drop out for those particles. Then the air box is typically relatively large to suddenly remove the air pressure difference and let any remaining particles settle down, plus the filter is positioned upside down. All these work in similar principles as the old school oil baths (or to some degree your bagless cyclonic vacuums) to reduce the particles before they hit the filter, but without any need for maintenance or contamination of MAF from the oil. The contamination from the oil may outweigh the benefits. So it's not uncommon for the Air filter interval to be 30k and they still are pretty spotless at that interval. But then the fast and furious crew mod their car with a cold air intake "straight" pipe and remove the ducting and particle catching or escape paths, then consider it an upgrade because "more air gets forced to the engine".
 
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12,925
Location
Northern Kentucky
Also on another note the newer formulation looks more desirable with moly and Boron. The older formulation seems to be a cheaper Ashland product , although it did have nice ZDDP
 
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5,707
Location
Atlanta,GA
Originally Posted By: raytseng
The ducting of the air tubes in a lot of the modern vehicle works in the same way to fling particles out of the way before it gets to the filter with an escape or drop out for those particles. Then the air box is typically relatively large to suddenly remove the air pressure difference and let any remaining particles settle down, plus the filter is positioned upside down. All these work in similar principles as the old school oil baths (or to some degree your bagless cyclonic vacuums) to reduce the particles before they hit the filter, but without any need for maintenance or contamination of MAF from the oil. The contamination from the oil may outweigh the benefits. So it's not uncommon for the Air filter interval to be 30k and they still are pretty spotless at that interval. But then the fast and furious crew mod their car with a cold air intake "straight" pipe and remove the ducting and particle catching or escape paths, then consider it an upgrade because "more air gets forced to the engine".
....and because they're getting oil consumption they tear down the engine and see vertical scoring of the cylinder walls.
 
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1,769
Location
Toronto Canada
I had two VWs in the 60's. The oil bath air cleaners held huge amounts of dirt and were very easy to clean. I have no idea as to how well they filtered the air but I can see why they would be used in extremely dusty conditions. Far cheaper than changing a paper element everyday.
 
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12,925
Location
Northern Kentucky
Originally Posted By: 901Memphis
Also on another note the newer formulation looks more desirable with moly and Boron. The older formulation seems to be a cheaper Ashland product , although it did have nice ZDDP
Whoops I posted that in the wrong thread.
 
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12,925
Location
Northern Kentucky
Originally Posted By: Garak
Originally Posted By: 901Memphis
Whoops I posted that in the wrong thread.
I was going to suggest a contest to guess the correct thread. wink
Correct thread I tried to post it in. http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3504268/Re:_VOA_diff,_same_store_brand#Post3504268
 
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512
Location
USA
I started my career on oil bath filter equipped diesel engines. A properly sized oil bath filter can be very effective...but it has limitations. The way it works is radically changing the direction of air flow just above the oil reservoir. Dirt particles don't make the 180 degree turn so they end up in the oil. A certain amount of oil mist ends up on the metal mesh screen fastened above the oil reservoir. That stops more particles. The limitation is the fact that these filters require good air velocity to drop out the particles. They don't work well at idle. Construction equipment and farm tractors don't sit around idling. In practice, they usually run constant rpms, close to or at governed rpm. So, a paper filter is much more effective for on highway use.
 
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6,388
Location
Washington St.
Oil bath air filters were very important in the Pacific Northwest in 1980. The eruption of Mt. St. Helens and the very fine, very abrasive ash that went almost everywhere was a big problem. An oil bath air filter jury rigged in front of the normal air filter was a huge help. Otherwise....
 

columnshift

Thread starter
Messages
233
Location
Minnesota
self thread necromancy smile So under severe duty conditions (like sandstorms?) such that you'd be plugging an air filter every day it sounds like it could save money. But would having an oil bath prefilter be more effective than any other kind of washable prefilter? I guess for that matter why aren't all car air filters washable, like the spongy stuff in my lawnmower... Is there something scientific I could read like regarding particle size filtration effectiveness of different filter types vs whats the most danger to an engine?
 
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6,765
Location
Fort Lauderdale, FL
My big Hyster lift has one. It filters the air from the top of the driver cage before hitting the cyclone cap inside the paper filter housing, and then hits the paper filter itself before going into the engine.
 
Messages
215
Location
AZ
I remember reading about many seized engines from volcanic dust. It isn't good for your lungs either. I have seen trucks seize engines when using a paper filter in the desert. Also a thing called dusting an engine,Where it seizes from dust from grain.What i saw was an Bobcat that was locked up solid. Daily,Maybe hourly cleaning was needed with paper filters. I wonder if oil bath filters are the best in severe conditions? Much of the heavy equipment i saw had a filter in a filter. And yes for normal use a paper filter is ok. I used [email protected] filters in my dirt bikes with no problems,oiled cloth filters also.Sealing the intake edges with lite grease helped.
 
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