oil bath air cleaners - pros and cons

[Guest]

Have a "54" buick with an oil bath air cleaner and always felt like they did more harm than good. First new car I bought was A "56" Chevy with a power pack and it came with an oil bath air cleaner also, but with in the first year a service bulletin advising to run them dry and just clean the filter element as normal. So are there any opinions or facts one way or the other?

Thanks in advance,

Chuck [color:"red"]

[Guest]

I have an oil bath on my 1950 Buick....

one draw back is when the engine "sneezes", or back fires, the rush of air out of the carburetor blows the oil all over the under side of the hood.

check the timing!!!

[NTX5467]

An oil bath air cleaner was pretty much the norm before the technology of paper air filtration progressed in the '60s. When paper filters became popular in the earlier '60s, the oil bath was still listed in some truck applications as "heavy duty" or "heavy duty/fleet" (in certain car applications) for several years.

As the air changed directions in the oil bath unit, I suspect the theory was that the heavier particles would slam into the oil instead of changing directions and then the oil wetted "horse hair" element would catch the rest. I know that on the tractors we had, the sump with the oil in it would have lots of goop/sediment in it, especially during the dry/dusty seasons. Oil was cheap back then and so was labor time so dumping out the oil and sediment in the oil drain area, wiping it out, and washing the rest of the filter in kerosene (or similar), and then putting the correct amount of oil back in the reservoir was not that expensive to do or needed to be done that often.

As you might recall, the hot rod V-8s from the earlier to mid-50s had a dual element (one on each side) oil bath air cleaner assembly. Other than obviously restrictive, they were bulky and expensive to build. Of course, filter case design and underhood packaging were later issues too. Paper elements were much more compact and cheaper to build and maintain--not to mention not having to worry about oil spilling out on hi-g force turns or during backfires. As good as they might have been for their time, they probably were not as air flow or air filtration efficient as the later paper filters.

Enjoy!

NTX5467

[Matt Harwood]

With that in mind, has anyone converted an oil bath air cleaner to a paper element while keeping a stock exterior appearance? I'm thinking that I can probably adapt the canister where the oil and filter element live on my '41 to hold a conical or cylindrical paper filter. Has anyone done this or heard about it? I was hoping to find a second filter housing on Ebay or something so I could experiment.

Thoughts?

[our51super]

Hi,

We converted our oil bath air filter to a paper element for the reason mentioned above. One day the car spit up through the carb and there was oil everywhere and some of it caught on fire. For a 1951 Super, the following air filter will fit nicely inside the original filter 'casing': [color:"blue"] Purolator 30052. I'm sure this filter element will work for most Buicks with straight 8s.

Cheers!

[Guest Dynaflo2]

Crin,

Regarging the air filter, I believe your engine is the 263 CID. Do you know if that air filter you mentioned will also work in the 320 (1951)? If not, do you have a reccomendation? Thanks!

[Guest]

In 1962 I was driving a 53 Special and was thinking of converting the oil bath air filter to a paper one. At that time I was working for a GM Truck Dealership and the shop foreman showed me the spec's about the size of pieces (microns) that will pass through the air filters. The oil bath filters filtered out about 70% more bits that the paper filters of that era. We believed that convenience and cost were the only reasons for the change to paper. I drove my Buick 190,000 miles before overhauling the engine and then another 60,000 before selling it all with the original oil bath filter.

Happy hobbying

[our51super]

John,

You are right - we have the 263 cu. in. engine. I don't know if the air filter casing is different for the different engine sizes. Common sense tells me that they should all be the same - or close enough for what we're discussing. The way I found the filter I mentioned above is by taking the air filter casing to a parts store and telling them what I was trying to do. We just went through about a dozen air filters until we found one that fit nicely in the metal casing and gave the appropriate clearance so air could still make it in.

I think the filter above will work for all straight 8 engines regardless of displacement. To be on the safe side, bring in the whole air filter with you - just clean out the oil first.

I have seen a similar discussion here about oil vs. paper air filters and then as well as now someone made a great point about how the oil filters clean the air better but there are added safety benefits to a paper filter. One day I was doing something to our car and the air filter casing just started leaking oil - just like that, out of nowhere. It just was time for it to leak I guess. Personally I am a neat freak and a perfectionist and I love things clean, original and just all around 'perfect', (drives Teresa - and her wallet crazy) but if it something small like this, where only a trained eye will catch it anyway I usually tend to bend the rules a bit. Plus it keeps me from cleaning oil off a newly detailed engine from time to time.

Cheers!

[our51super]

Here's a picture of what it looks like installed:

Cheers!

[rmartens]

On my '56 Century I use a paper element off of a mid-80's Chevy S-10 pick-up. I did what one of the previous posters did--cleaned the housing up and took it into the auto parts shop until I found something that fit snuggly and sealed well. If I remember tonight I'll check for the part #.

[Guest imported_scotties1]

Crin.......Is it possible you mean a Purolator 3052 ?

I can not locate a 30052.........Al

[Guest]

I found several of these comments interesting. One owner had great experience with his oil bath type filter in his 53 Buick while another mentioned how there would be sludge in his oil pan (farm implement). As a Mazda technician I do a lot of engine work and never see accumulations of sludge in modern motors with frequent oil changes (3000-4000 miles)

Coincidentally Mazda (and maybe other manufacturers) use "wet" air filters OEM factory including replacement OEM. What this means is the paper air filter is misted with a light mineral oil, almost not noticeable to the touch.

I believe paper filters are superior to oil bath, however, make sure the air does not have any opportunity to bypass the retrofitted paper filter (path of least resistance theory) and maybe try a fine misting of mineral or vegatable oil (use one of your wife's old perfume bottles) This improves filtration and should not hinder air flow

Bryan Moran

ASE Certified Master Technician

Mazda Master Technician

BCA 28571

1964 Buick Wildcat convertible

1961 Buick Electra 2 door hardtop

1972 Buick Electra 2 door "Limited"

[old-tank]

Bryan

The sludge mentioned is the accumulation of filtered dirt in the oil reservoir of the oil bath filter. Aside from being messy to clean and maintain they will filter better and flow better than any paper filter.

Willie

[Guest rlbleeker]

I don't know if the oil bath filters better, (probably depends on the filter, how well it diffuses the air) but they can handle a lot more dirt. It will keep working as long as there is adequate oil in it. Long after a paper filter would have become completely clogged. We dry land farm out here (very dusty) and most everything uses an oil bath backed up with a paper filter. I imagine this would have been an issue in the 40s and 50s when the majority of the roads were dirt.

[Guest]

I wrote a letter to the Fram Corporation back in the late 60's asking about the pro's and con's of different kinds of air cleaners. This was the reply: General Motors paper filters removed anywhere from 85% of the dirt on up to 99.99%, Fram used only paper that would remove 99.99% of the dirt, oil bath air cleaners removed 92 to 96% of the dirt, and the oil wetted elements removed anywhere from only 20% up to 94% of the dirt. I have noticed that today's most popular oil wetted air filter never mentions the percentage of dirt that their filters remove.

[NTX5467]

When talking about the effectiveness of any filter, you also need to be aware of the "down to ____ microns" size of the particles they'll trap. For example, the AC-Delco oil filters were always good filters, but the Duraguard upgrades in the '90s started talking about particle sizing that they'd filter down to. It was something like a 50% improvement over the earlier filters we'd used for years.

GM has used several different protocols on air filters since the later '60s. There was the basic paper element (usually had some "oil wetting" in many cases), the basic paper element with an oil wetted foam wrap, and the "dry" versions. Unfortunately, when the oil wetted paper elements stayed on the shelves too long, the oil soaked into the cardboard package, which was sometimes worse with the foam wrapped versions. Seems like I recall them putting the foam wrapping in a plastic bag that kept the oil migration to a minimum. Not all applications used the oil wetted paper elements, though. I don't recall any other filter manufacturer using oil wetted paper elements so it might have been a helper to catch more of the dirt in the intake air.

I suspected the foam wrap was to be sort of a pre-filter for certain applications, but was not limited to any heavy duty applications. It could be cleaned and reused so I guess it was a "value added" issue so the basic paper element would last longer or perhaps it was a stop gap measure to increase filtration efficiency.

For those heavier duty industrial applications, no doubt the oil bath backed up with a good paper element would be better for total filtration down to a smaller micron size particle than just the oil bath would catch itself.

I did use one of the Fram paper "dual filters" on my '77 Camaro once. Even with the 305 2bbl, I noticed it did not run as good as the standard A329C filter. Somewhere, there's a good compromise between filter restriction, sizing, and filtering abilities.

Enjoy!

NTX5467

[BuickNut]

Anybody know of the filtering capabilities of the K&N Filterchargers ? I have them in some of my vehicles, and noticed an increase in "seat of the pants" acceleration, but now that I think about it, I'm not sure of the actual filtering capatilities of the unit.........

[Guest]

I have tried twice to find out the filtering capabilities of the K & N filters but they won't say.