The point I was trying to touch on was...

How long was the vehicle driven with an empty sump (and thus no oil pressure)?

i'm losing sleep thinking abou this!! maybe 30 miles!!

Try not to lose sleep, just start chalking it up to experience. Why on earth did you drive you poor car 200 miles while belching huge plumes and without checking your oil? Always check your oil, all the time, every chance you get.

Ash

__________________
Ash Peltier - tools, truck, tales
---------510-331-4118-----------
1982 240D - (272,000)
1998 Honda VTR1000F(RT) Superhawk Freeway (58,000) "Madrid"
1996 Toyota T100 4x4 (84,000) "Mary Kay"

I'm not a bad mechanic, I've rebuilt two diesels and a ton of other engines, but I got Fatigue from being 44 and I was short slept that day..so I just poured on the gas and kept on Going...

For the record, I got up 20 minutes ago and drove the car again. Its not smoking orsmelling bad
I dont think the engine was affected...I think its good, its not knocking its just out of tune, got a clogged EGR and slow ALDA and a host of performance problems, it sounds not like shot bearings, but more like badly tuned and wheezing badly..

Besides who would think just because I rearranged a hose in the engine compartment ( i used a 5/8 inch hose from Valve Cover to Air Filter) I would accidentally crimp it and block the PCV feature..

tomorrow at first light I hope to get some work in..

A similar thing happened to me last fall on a 300sd. I bought it one afternoon, drove it home, adjusted the valves, and drove it to work the next morning. In 12 miles I managed to loose 6 or 7 quarts - still trying to figger out where it went.
I shut the car off and started coasting when i saw the oil gauge fluttering between 2 and 3. it was too late. The car still runs, but it has some knocking, and smokes a bunch.
What bugs me is that I still don't know where all that oil went in 12 miles. I suspect that the car had bad blowby, and I lost lots out the vavle cover gasket, maybe it was not sealed tight - I did have to wrestle it into place, and I was in a hurry. Still, the engine bay did not look like it had 6 quarts scattered around. Some must have gone out the tail pipe.
I drove the car about 50 miles before I did the valve adjust - no oil loss, but something happened when I took off that valve cover.
The upshot is that I will be parting out an '81 sd soon. And I still want to know where all that oil is.

__________________
andy t
'78 300d
'95 volvo 850, wagon
'86 300sdl - engine out, maybe I'll have it rolling by June

whole bunch o' bicycles

It would be very helpful if our combined diagnostic skills can determine what happened in both these instances.
Both cases seem extremely odd. In both, oil must have been entering the intake somehow. If the bypass hose was crimped off in the recent case, I don't see how oil could be entering via that route. However, it seems to be the only route large enough for enough oil to travel through to consume that quantity.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

my feeling is that the blocked breather forced the oil out the exhaust..

I am sad as heck, I rebuilt this engine, it was a beauty. I also got my other Mercedes, my 240D, tanked in an accident. Now having maybe ruined two cars in three months, I am not too excited about rebuilding a diesel again..I may be buying a Kia or a Hyundai--

My Chinese astrology says my sign, the Boar, is having a Bad Luck year.
My wife told me to wear red underwear to ward this bad luck off. Well they werent kidding about Bad Luck!!! I maybe wearing 3 or 4 pairs of Red underwear, Red pants, Red shoes and Red Tshirts

But the issue is: How can a blocked breather force oil out of the exhaust? There are only two possible routes into the exhaust to my knowledge. Either it enters the combustion chamber via the intake manifold or around the valve stems or piston rings, or, it enters after the combustion process through the turbo seals.

I seriously doubt that bad turbo seals could pump that much oil past them. This leaves the sole option being direct migration into the combustion chamber. How could that possibly have happened? I don't think that much oil could get by the rings and valve seals in that short a time.
This pushes me to the conclusion that it had to enter via the bypass tube. Could the baffle in the valve cover have a problem resulting in the oil getting vacuumed into the bypass tube?

Can anyone else come up with an alternative hypothesis? I may be misled by the fact that I've had this happen before on a gasser.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

What's the bypass tube?

So what if the PCV function of the valve cover breather were blocked? Wouldn't the increase in crackcase pressure force oil up the hose on the oil-separation device, the one between the breather and the intake?

My system's not stock, so maybe I'm not making sense, but I have a cannister full of plastic mesh that is supposed to (I gather) take the oil out of the blowby and allow it to drain down this hose to the sump.

Ash

__________________
Ash Peltier - tools, truck, tales
---------510-331-4118-----------
1982 240D - (272,000)
1998 Honda VTR1000F(RT) Superhawk Freeway (58,000) "Madrid"
1996 Toyota T100 4x4 (84,000) "Mary Kay"

Sorry, should have written breather tube instead of bypass tube.
Yes, I think that pressure could push oil back up thru the oil separator device (if the engine has one) and into the intake. That could cause the consumption.
Would the amount of pressure necessary to push the oil back up thru the oil separating device be less than the pressure necessary to activate the shut off valve? If so, the conditions should be repeatable by simply pinching off the breather tube. Nobody in the past, when reporting the amount of time necessary for the engine to shut off when blocking the breather tube, has indicated that the engine started smoking during that process.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I believe there is a check valve at the nipple of the oil pan connection that will prevent oil from going up the tube.

I doubt a blocked PCV would generate enough pressure to blow 7Q oil past a check valve, *not* blow a seal/gasket, not put pressure on the shut-off diaphram, and have normal performance. Something is very odd here. Did you check the coolant for any signs of oil in it? Did you do anything to the oil cooler lines?

In my case, there is no oil in the coolant, and there are no visible leaks. The car still runs, but not well, I am guessing that the rings are tempered. It starts, and I have driven it up and down the street, but smokes like a chimeny, and at idle the engine shakes enough to make the whole car wiggle on the suspension. Obviously is is a lost cause now. I paid $1100 for it with the intention of driving it for a year or two, now I would just like to get close to that amount by parting the bejeezus out of it. More than 2 hours of driving time with it would have been nice though.

__________________
andy t
'78 300d
'95 volvo 850, wagon
'86 300sdl - engine out, maybe I'll have it rolling by June

whole bunch o' bicycles

I went out to check..

Clearly the engine is shot. If you were to fix the smoke problem, or at least reduce it to an acceptable level, you could drive it until it plain out dies. This is a fairly bulletproof engine. The fact that it even runs decently after the event proves it's durability. The only question now is how long will it last in it's current level of damage?

If you keep driving it, it won't hurt the body, transmission, or anything but the engine. You could always part it out at any time.

I worked on it all day. Its just sluggish off the Line. Today I took off from work. Retimed the engine, (advanced it 3 degrees),
plugged the egr, advanced the ALDA and cleaned out the crud in the banjo fiiting--
The car isnt smoking...

Now I am back to Square 1. The car is still sluggish.
BTW, I rebuilt my AC system last month-- and its so damn great, its freezing cold--is it hogging the engine?---thats why I started this whole mess to begin with and changed the fuel filters

,
Once I had a Ford Escort 83, brand new. Jiffy Lube left an extra gasket in place and the car died on the road one month after I took delivery on it. Engine lost all the oil and the car stopped in the road. Put 4 qts back in and used the car for a 100,000 miles...