Rainy day here so I was browsing the forum. After reading all the issues folks have with the oil separator in the air filter housing, I got to thinking. Couldn't you remove the oil separator unit inside the air filter housing, and just run a tube from where the valve cover vent tube comes into the air filter housing down to the drain tube that goes to the pan. Basically bypassing the oil separator, but leaving the air filter housing and valve cover vent tube looking stock? Any feedback welcome......would it work or cause issues.

What ever is in the Blow-by be it gasses and or oil vapor it needs to be cooled down and condensed anything left goes into the intake and burns inside of the Engine.

If the Vent hose went directly to the drain tube and was sealed the Blow-by pressure builds up and pushes the Vacuum Shutoff towards the shut off position and kills your engine.

One person blocked off their vent and the pressure built up enough it popped out the crank seal but that is unusual. I put my Thumb across the vent elbow opening and it shut the Engine off.

There are models with no Oil separator at all and the vent hose just goes into the intake.

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84 300D, 82 Volvo 244Gl Diesel

Interesting.....never thought of that aspect....thanks, I learned something!

I had to make another separator when I did this: http://www.peachparts.com/shopforum/diesel-discussion/280376-washable-air-filter-intake-mod-larger-breather.html

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84 300D, 82 Volvo 244Gl Diesel

Remove the cover of the separator and put some stainless scrubber pads inside to increase coalescence surface area.



oh my god, thats not an improvement over stock in any way!

Why not? Looks good to me.

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CENSORED due to not family friendly words

The latest iteration of the forum contrarian. Haven't you noticed?

When my engine was ruined by a disintegrating turbo, I had a reliable shop replace the block. However, it seems that the replacement block, that they said was off an early 300SD, did not have a port to return the oil from the air filter separator.

The drain port of the filter housing is plugged. I have a removable port on the top of the separator. Each time I do an oil change (about once/year or every 6000km) I use the MightyVac to suck out any collected oil. There is never that much there. I presume some gets sucked out into the intake.

Seems to work and not much different from the cars without an oil separator.

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Graham
85 300D,72 350SL, 98 E320, Outback 2.5

Hot air, much smaller filter than stock, and that ccv filter has no baffles to direct flow.

I took the cover off inside the lower air filter canister and added a bead of RTV, re installed it and bent the four tabs so it was held tightly in place and discovered far less oil ist inside the dry & clean part of my stock air cleaner assembly .

I don't generally believe I can re engineer things better than someone who does it for a living but this simple thing did help as the dry paper elements no longer get wetted with oil mist .

Washable air cleaners don't filter out the finer wear particles and always cause shorter engine life .

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

My 1985 CA 300D has a different frame-mounted air cleaner. M-B simply tee'd off the valve cover vent, with one tube going straight into the turbo inlet duct and another tube going to the air filter housing (downstream of air filter). The upper oil pan has no oil drain tube stub. Perhaps the plan was for oil mist to get sucked/dripped into the turbo inlet, but the oil filter housing would also get oily at the bottom, at least when I bought the car w/ 279K miles and lower compression (guess ~280 psig).

After the OE engine failed at 330K, I installed a used engine (1982?), keeping its "federal" intake manifold and exhaust. Since the turbo sits lower, I cut the air filter housing outlet tube 1.5" shorter to match and used a new silicone hose elbow. Off the valve cover vent, I tee'd a tube to that engine's oil drain tube (where air filter sat), which seemed smarter than running the oil gunk into the turbo. I've noticed no oil at the air filter now, though that engine has perfect compression (>400 psig all cylinders). I also get no oil gunk on the turbo inlet vanes now, so even though I have no official "oil separator", the oil mist seems to settle out on the walls and run down that drain tube fine. I liked that approach so much that I fit a 1985 CA frame-mount air filter to my 1984 300D (has OE oil drain), mainly because it kept breaking the air filter mounts and bracket. I don't know if one could retrofit an oil drain stub to a 1985 CA upper oil pan. I understand there is a small check valve inside those, though don't know if mandatory for it to work.

A few photos which somewhat show it in both cars. Those who fuss that the 1985 CA air filter is "not avail" and/or very expensive never thought to stack 2 cheaper air filters as shown.

Attached Thumbnails

         

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans

Sealing the separator is in one of the old threads.

Please substantiate your claim on this concerning all washable air filters. The one I have is made By Fram and is not a foam or oil impregnated filter like the K&N. Amsoil also made a filter similar to the Farm Washable one.

It is common to wash the Air Filters on big rigs and other types of engine powered equipment. They actually sell special washers and even dryers for that. Of course they target businesses that own fleets.

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84 300D, 82 Volvo 244Gl Diesel

THANX Bill ! .

That even looks a little bit cleaner too .

I see you're running a KKK turbocharger, can you make any comments about that ? maybe in a different thread .

As far as washable filter efficiency , it's common knowledge, go look it up ~ I don't waste time in baseless arguments .

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

You're comparing an industrial application to a consumer application? You aren't comparing apples to apples.

The air filters you're referring to aren't "washable" but they clean them by reversing the flow of the air in a spinning cleaner. These filters are also expensive compared to ours and have a much longer serviceable life.

I agree that the premise that all washable consumer air filters offer less filtration for smaller particles.

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Onus probandi incumbit ei qui dicit, non ei qui negat

I recondition w123/w126/w124/w140/r107/r129/ steering boxes!


1984 300D "Elsa" odo reset 6/2011 147k
1983 300TD "Mitzi" ~268k OM603 powered
1995 E300 "Adelheid" 262k [Sold]

In order for that to be true they would all have to be the same and it is obvious different brands are made of different materials. That alone is sufficient to cast doubt on what you have said.

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84 300D, 82 Volvo 244Gl Diesel