(800) 853-2651
SHOP NOW

Oil Bath Air Cleaner on a Diesel?

Fawteen

Fawteen

Well-known Member
Location
Downeast Maine
This is the air cleaner off the little Shibaura diesel I'm working on.

It certainly appears to be an oil bath cleaner but there are three questions in my mind:

1. Why is there no "fill level" line on the cup. Perhaps there was a decal at some point?

2. Can a diesel pull oil out of the cup and "run away"?

3. Assuming it is indeed an oil bath air cleaner, how far would you fill the cup?
ac1.jpg

ac2.jpg
 
It's difficult for me to figure out what's what from the picture. Is there some kind of filter media in the part with the holes? Like steel wool? There certainly needs to be enough oil to keep that bathed in oil under suction, so no free air gets through. I'll guess the cup needs to be pretty much full.

My old 4020 has an oil bath air cleaner. It running away never occurred to me!
 
Yes, there's a coarse steel mesh in the top of the air cleaner (the part with the holes). Looks pretty much like the Donaldson oil bath that was on my F14.

Good to know diesels did come with oil bath cleaners. I hadn't thought about it, but now that you mention it, I guess the oil is about keeping the mesh misted with oil from the air flow. I thought the air actually traveled [i:654c4848f0]through[/i:654c4848f0] the oil but that doesn't make a lot of sense when I think more about it.
 
Agree that oil has to be present to coat the wool. Wonder why no visual indication that oil was ever present to be sucked up and trapped in the media. It's obviously a serviceable item as the clamps are a servicing mechanism How is it mounted on the engine.......cup down such that it could hold oil? If it's mounted as shown in your first picture and the cup is on the bottom...seems to be 3 pieces as the cup in pic #2 has no "port" attached......like in my Fords, the air flowing through the device creates a differential pressure which sucks the oil up into the medium, coating it and when the engine is off, the dirty oil falls down into the cup and the dirt particles settle to the bottom to be removed and fresh oil added at servicing intervals.

My 2000 and 3000 Fords both have oil bath air cleaners. Going to say that the molecules of any oil that may get sucked up into the engine are too large and require too high a temperature to combust supporting not a concern for runaway.

I'm going SWAG the cup is full and needs to be serviced regularly. Why don't you fill it full (can't get any fuller than that) and try it out. Run it for say, 8 hours, let it sit for a day or so and pop the cup looking for dirt and checking the oil level.
 
All the older diesels that I ever saw had oil bath air cleaners. Cat, Allis, Ford and John Deere. I think if you over fill some does get pulled into the engine but not enough to cause a run away. Maybe the owners manual discussed how deep to fill the cup or gave an amount.
 
(quoted from post at 05:57:18 11/24/20) Yes, there's a coarse steel mesh in the top of the air cleaner (the part with the holes). Looks pretty much like the Donaldson oil bath that was on my F14.

Good to know diesels did come with oil bath cleaners. I hadn't thought about it, but now that you mention it, I guess the oil is about keeping the mesh misted with oil from the air flow. I thought the air actually traveled [i:2189ee7077]through[/i:2189ee7077] the oil but that doesn't make a lot of sense when I think more about it.
Click to expand...

"I thought the air actually traveled through the oil but that doesn't make a lot of sense"

Typically, the air inlet tube (in the case of your setup, the area where the round holes are) IS below the surface if the oil in the cup when the engine has been shut off for a while and the oil has drained down from the mesh into the cup.

That would mean there must be a fair amount of oil in the bottom cup.

Yours must be missing a gasket or a seal ring, I think it would make quite a mess in operation as the oil returns from the upper housing to the cup, or when it sloshes around.
 
Possible, but not likely, unless you are operating at such an extreme angle that would allow the oil to spill up the connecting pipe to the intake manifold. If an engine has a lot of blow-by and a PCV system it can happen, but you need fairly high RPMs to draw enough fumes through the engine and into the cylinders.

I once had a VW rabbit with a diesel that would enter this mode when on the expressway. At high RPMs it would sling so much oil off of the overhead cam that the PVC hose attached to the valve cover would suck up some of that airborne oil, route it to the combustion chambers, and away we'd go! It was like a red-neck cruise control- just take your foot off the accelerator and hang on! You had to randomly ride the brakes to control it and also to slow the engine down to below 2000 RPMs to break the feed-back loop. Luckily, my clutch didnt slip or it would have been uncontrollable from the drivers seat. The cure to disable this low-tech hyper-drive was an oil baffle VW came up with to install over the cam, under the valve cover, to keep the oil from slinging around in there.
 
Other option is a crankcase breather whereupon the media is oil soaked but no oil is in the cup. My 4 cylinder early 1960's Fords had a similar steel wool mesh screen and cap on the side of the overhead valve (OHV) cover. During periodic maintenance, you remove the cap and screen, soak it in gasoline or such, dry, oil soak and reinstall.
 
There is an o-ring for the groove of the cup. I removed it when I dunked the cup in the electrolysis bath. Hadn't put it back when I took that picture.
 
We have 3 diesels with oil bath air filters. MD ,D-4,No.-6 Traxcavator both caterpillars. All with the oil bath filters on them. Never had a problem with runaways with the 2 dozers and have ran them at some pretty steep angles both sideways and endways.
 
All the old diesels I've run had oil bath air cleaners including the two I use now. Case 730 and Massey Super 90 Perkins. Both have a clearly indicated line on the cup saying "oil level". I've never heard of one running away on the oil in the cleaner. Anytime I take mine apart to change the oil I can see the steel wool mesh is well soaked in oil.
 
Oil bath was common before the modern dry paper element. My JD 730 diesel;farmall MD;WD9;560D had oil bath,I think my buddys early 4020 also had oil bath.
 
In theory, yes a Diesel could suck the oil out of an air bath and run away. In practice, not going to happen, as the mesh above the oil does a real good job keeping the oil from sucking up. I pulled the mesh out of my MH44 EFI in preparation for converting to dry filter. The tractor sucked the oil out of the bowl when under load.
 
i will put money on that as its a dry air cleaner. how does it sit, flat? is that a rubber cup in the second picture?
 
Lets get back to the crankcase breather. If this isn't it, it has to have one or a PVC (doubt). Find it ;otherwise that's what's in your picture. Wink!
 
When turbochargers were added to diesel tractor engines manufacturers switched to dry air filters. Did aftermarket turbocharger kits include a dry air filter too?
 
Crankcase breather from the top of the valve cover with a cap and a tube just runs down the side and drips on the ground.

EPWho? "8^)
 
Good morning: I don't see how the engine could run away with only the oil in the cup. How long could that make it run? Now where there is a continuous source of oil, as in one comment here, possibly it could run away for quite a long time. I am not a diesel person, but somebody reading this knows how this stuff works.

Dennis M. in W. Tenn.
 
It’s hard to tell but I am referring to that cup in the second picture. Does it have a bottom or is the bottom open. It appears like that is your dust cup that u would empty on a dry set up.
 
It's a closed cup. I sand-blasted it prior to painting so the bottom of the cup sort of matches the counter top.

It doesn't have the little rubber..."gate" for lack of a better term... that dry filter cups usually have for emptying the dirt.

I've got a dry filter on my Kubota B2650 that has a cup much like that but it has a rubber plug to empty the dirt.
 
ok, i will go with dry. plus its the sideways mounted ones that have the gate thing your talking about. i am the odd guy on this so see what happens. lol.
 
I had a 1365 diesel that had an oil bath air cleaner and it sucked all the oil into the engine and burned it, there was no run-a -way and the indication of the condition was when using the thermostarter there was no puff in the air intake, I removed the air filter and did a thorough cleaning with a hot pressure washer until all the dirt I could get out was gone, then had no oil loss afterwards. Thanks.
 
Air doesn't actually go through the oil in the air cleaner. They work on an inertia principle. The air makes a very sharp turn at the bottom of the assembly, above the oil. Dirt and other particles in the air can't make the turn and then get trapped in the oil. The oil film on the mesh traps the rest of the particles that did make the turn. That is why you find all the crud in the bottom of the bowl when cleaning; the particles settle out of the oil. The pre-cleaners on dry filters work by a centrifugal principle: heavier particles can't follow the air flow to the center of the assembly, collect on the outer periphery and drop to the bowl. zuhnc
 
The modern twist on the oil bath air filter is the K&N oiled filter element. As with the oil bath, the oiled filter will capture dirt particles passing by.
 
You must log in or register to reply here.

Similar threads

5
Sealing a 1/8 inch hole
Replies
11
Views
668
stevieb49829
stevieb49829
T
44 A oil bath air cleaner
Replies
3
Views
324
Tstoner
T
C
Oil bath air cleaner mesh
Replies
17
Views
1K
ss55
S
L
1958 Dexta: repeated air in fuel line
Replies
10
Views
1K
LJ15
L
C
Air cleaner
Replies
2
Views
339
CharlesG
C
Tractor Parts Tractor Manuals

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Copyright © 1997-2024 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters
Website Accessibility Policy

Back
Top