Oil Bath Air Cleaner Question

[GB SISSON]

I have an oill bath from a '47 V8 truck. I like the look and want to repair it. I have also heard they are quite effective. My problem is the base where it mounts onto the carb has a flange about 4" in diameter. This flange with it's attachment hardware and tube has come adrift from the main bowl housing. Looks like it was spot welded, but most have failed. With the top part removed from the cleaner and set aside, I cleaned the dish that holds the oil and placed it upside down. I don't really understand the physics or air path of these things. I am wanting to bolt it back together instear of welding, but the bowl has a 'double bottom'. The interior space looks unreacheable. Will drilling chips be left in there? Does it matter? I certainly don't want them sucking into my engine. The entire air cleaner assembly has way too much rock and roll even though the clamp is properly attached to the carb.

[GB SISSON]

Does the intake air travel through the oil as bubbles and the oil grabs the grit out? What happens in the enclosed space under the oil resevoir tub? I see horizontal slots opening into that area just above the carb mounting clamp. I'm gonna go to the shop and pry my failing air cleaner apart at the base to get to the bottom of this. Chances are I still won't learn what goes on inside these things.

[Daves55Sedan]

Many of the original F1 and early F100 trucks up to at least '53 had a single-wall, single bottom design similar to the early Thunderbird oil-bath air cleaners, but shaped a lot different.
Cars with single bbl and 2-bbl carbs from around '54 thru '56 had double-wall, double bottom oil-bath air cleaners.
The removeable top of the air-cleaner has a steel-wool filter, held in place by a rat-wore mesh. This wool is coated with oil from the underside, then turned right-side up so that excess oil will drain into the oil reservoir at the bottom. The reservoir is further filled with more oil up to the fill mark.
When the engine is running, air is sucked in through the slot all around the top of the air-cleaner. The air rushes past the oil in the reservoir and sucked up through the oily steel-wool mesh. Notice how the air-cleaner top dips down into the reservoir with a sloped cone. This was designed to keep the cone awash in oil and having the ability to pick up the heaviest of dust entering the cleaner before air gets to the steel-wool above. The air must get past the oily steel-wool in order to get to the void in the middle where the carb throat is. During the process, dirt sticks to the oily steel mesh until it gets heavy enough to drop out of the steel-wool and into the reservoir below. That is partly why you see so much oily dirt (almost like mud) in the bottom of your reservoir when you clean it.
Not sure why they went to a double-walled construction for the car air-cleaners other than as a means to add the baffle at the front, so that the incoming air would be directed all around and to the back of the air-cleaner.
But when they designed the T-Bird air cleaner, they achieved this by cutting the metal large at the front and bending the air-baffle into the main bottom piece that served as a reservoir, thus eliminating the need for double-wall construction.
Yes, the double-walled air cleaners do have a dead air-space between the inner reservoir and bottom of the can which is pressed air-tight. It serves no purpose at all.
It is also best to oil the vertical surface of the air-cleaner top that dips down into the reservoir. This will help to catch the worst of the incoming dirt.

[Daves55Sedan]

Originally Posted by GB SISSON

Does the intake air travel through the oil as bubbles?

No! oil travels PAST the top of the oil, but some dust is caught in the cone-shaped trap under the top as it is normally awash in oil while driving.
The air is cleaned primarily in three ways:
1) dust sticks to the oily vertical surface of the air-cleaner top that is recessed down in the reservoir can.
2) Some incoming dust is collected at the surface of the oil in the reservoir via the cone-shaped trap.
3) dust gets caught in the oily steel-wool encased in the top of the air-cleaner.

Originally Posted by GB SISSON

What happens in the enclosed space under the oil resevoir tub?

This is only dead-air space and has no value in the process of air cleaning, however the double-wall construction between bottom of can and reservoir must be air-tight/oil-tight to prevent leaking.

[Daves55Sedan]

Seeing how the ones I have are constructed (1955 Ford 272, 2bbl and 1955 Ford 223, 1bbl oil-bath air-cleaners), I don't think you can take them apart without destroying them. You might be able to patch one back together but it would be a feat to make it's construction air-tight as it was originally, and it wouldn't look original anymore.
In order to separate the outer wall from the inner wall, you would need to cut off the "lock-formed" top half from the bottom half. It could only be put together with a large custom-made one-hole v-shaped pipe-clamp. It would need to be fairly precision.
The bottom connection for the carb attachment is a whole nother problem.

[GB SISSON]

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Thank you very much for your knowledge on these air cleaners! Looking down into the bowl it is obvious that the precision pressed in oil tub is leak proof and seamlessly joined to the outer shell. The spot welded bottom flange was held on by only two spot welds as the other ten or so had failed. This action had fatigued the steel on the bottom of the outer tub, tearing it in places. I am thinking of screwing the flange back on with self tapping screws like 1/2"x10 pan heads with epoxy paste as a bedding between the two pieces. There does seem to be slots into the bottom cavity that are open to the carb throat, I will delve deeper after work today and get some pics too.

[19Fordy]

Could you use pop rivets?

[GB SISSON]

My shop where I work on my trucks is unheated. I can survive that, but epoxy and paint don't do to well in the winter. Wednesdays are my bachelor night when my wife works a 24 hour shift with her eldercare work. I pre-heat the parts on the wood stove, spray out on the back porch and return them for a few heat cycles on low with all the doors and windows open. You can see the flange I screwed back on to the bottom. It isn't pretty but I got the surfaces very clean with sandpaper. scotchbrite, laquer thinner and brake parts cleaner. That prep was done in my cabinet shop with a big sheet of cardboard over my work bench. At least I didn't put any of this in the dishwasher. It's a new one (from a remodel) and she hasn't shown me how to run it yet.

[Jacques1960]

Living in Maine, I appreciate your resourcefulness ! My wife recently found my hunting boots in her oven (on “warm”) helping to get the waterproofing into the pores of the leather.

Like the dishwasher “parts cleaner” idea !

Btw, you might be able to appease her by offering to share your engine cleaner spray - works a charm on our stove top !

[hotrodcbx]

Love your stove!! Would look great in my cabin in norther Ontario!!!

[mfirth]

G B, I love the stove too, and as always enjoy your posts. Thanks !

[GB SISSON]

Originally Posted by mfirth

G B, I love the stove too, and as always enjoy your posts. Thanks !

Bought it 41 years ago when I built my house. The body of the stove is 1/4" wall 24" steel pipe. The glass in the door consists of a piece of 1/4" pyroceram glass on the inside against the flame and the outer glass is a standard 9" pyrex pie plate, available at the local hardware store. When I built the house I placed the chimney in the center of the structure to get even heat throughout. Because I scrounged 2nd hand wood windows we have no double pane glass and just 2x4 walls, so we burn about 4 cords a year in our moderate climate.

[cas3]

Air cleaner looks good, Stove looks good, carry on ! PS, I have one of those magic fans on top my stove too. Doesn't do much except entertain folks who cant figure out how it works, but fun to have

[petehoovie]

[cas3]

I forgot to mention, better stay away from that dish washer if ya know whats good for you buster !