Have you had anyone follow you to see if you are laying a smoke screen behind you??

I have done the heavier oil thing a few times myself. People reporting consumption picked up is interesting. I will keep that in mind. Was not my own experiences but they are limited to only a few.

Might also depend on exactly what the cause is. If the bores are not in fair shape especially The argument of possible increased consumption sounds more plausable to me.

On occasion like some earlier fords the manufactures seem to get the compression rings right by design and they are the last thing to go. The thicker oil may be at it's best when the oil ring grooves are worn and the thicker oil tends to lessen the pumping effect.

On a fair bore even with tired oil rings I cannot see more gettting by them to coat the walls. The thinner oil just has to flow easier. In my opinion and it is just that an opinion.

The engine was probably never seriously overheated. The temper would have left the top compression ring first. As for the valve rubbers as you say a chance .Especially if they have rotted away or seriously deteriorated with time. Little time and effort expended. Normally I personally would not expect to lessen the oil consumption much if any by changing them if they look fair on older mercedes diesels. Do try to keep an eye out for a loose guide though as that would do it. It is also too bad you do not have acess to a bore scope. To examine for any evidence of original cross hatching as it lasts so long with mercedes engines. Perhaps not your particular vintage though.

Although I suspect you would not have got your compression numbers with bad scoring present.. Estimated milage on the car might be helpful even if you are unaware when if ever the engine might have been rebuilt. The higher consumption at speed normally indicates wear. Yet again all 240ds including the last production years use more oil at speed I believe.

There has to be some 40 weight diesel oil around somewhere in your area. Even wallmart carries it I think or a local napa type store might order in some for you with their weekly order. At least their is not a price penalty. Usually it's cheaper.

It would not surprise me to know there's a bit of smoke coming out its tailpipe but I have never observed it myself. As you know, nobody stays behind you very long when you drive one of these, usually it is because you are going so slow but the smoke is also a reason to pass ASAP. These early ones do smoke more than later ones too because they have no emissions controls of any kind.

I guess I was hoping that maybe it had some rings stuck from the cold running and poor spray pattern it had been experiencing previously. I can say I have been driving it with a lot of "spirit" these past 500-600 miles and it does run smoother and idles better than it did when I first got it but I would say since the oil consumption is about the same that probably is more a result of the valves getting cleaned up a little rather than any ring changes. I was also thinking of doing a cold compression test to compare to the warm one and see if that sheds any light on it.

I guess I can keep driving it, adding oil and will order the valve seals. Maybe a miracle will happen and it will cure itself. I don't think I am doing any harm to it since it keeps running better and better. It's been getting around 25 MPGs even with my lead foot trying to blow the crud out so it's certainly not totally out of whack and the timing chain only shows about 4 degrees of stretch so that is minimal too. All in all it is not a bad little driver.

I guess worst comes to worst I just will keep driving it and brag about having a 240D which gets 500-1000 MPG (of MOTOR OIL!)

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

I would try the seals and see if it helps. If not you will have to decide to either live with it, get into the engine, or replace the engine.

I'll probably do the seals and see. Oil is cheaper than a new engine and since it runs fine otherwise it only makes sense to drive it into the ground before replacing it. As I said in an earlier post, I had one which burned a quart every 300 miles for a couple of years and always ran fine otherwise...I just lived with it.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

I started using more oil turned out to be the turbo. Check for shaft play.

He has a 240D, no turbo.

Did you use a catch can situation? If not, how did you return the 'seperated' oil to the pan?

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Cheers,
Robert

The VW breather drains back down the air inlet.

-J

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

Yeah, what he said...here's a photo:

http://www.peachparts.com/shopforum/attachments/diesel-discussion/54921d1210187390-some-mods-early-om616-oil-separator-gorilla-cable-bracket-fix-240d-mods-001.jpg

Unfortunately it made no measureable difference on the rate of oil consumption.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

You say a quart in 100/200 miles. Can you be more specific? Is it more like 100 or 200? Also, you might try a quart of Lucas in it. It has been known to work miracles on some engines. It use to be around 6 bucks, but it may be more now. I saw a quart of synthetic going for nearly 7 bucks now! I guess, it is not only diesel that has escalated. They tell me the cost of parts and accessories will all be climbing. Anyway it might give you some feedback on the issue.

Ok, I looked @ the picture and I see a pretty small oil separator. Forgive me if I'm being ig'nant, but if you have significant blowby, it could overwhelm that little guy. I think I'd rig a catch can and go for a long drive and see how much appears b4 discounting the blowby possibilities.

Perhaps its a combination of factors.

Is that OS for a <2L engine?

__________________
Cheers,
Robert

I put the range because I think for slower, around town driving I could get 1/200 but if I put it on the highway it would be closer to 1/100.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz

Well, it is certainly worth a try to do that for sure and is easy enough to do so.

__________________
Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz