I never thought, that I would be talking about an issue such of this, three weeks ago, after having taken that head off and getting it back on and getting the car to start, again. But, I really am enjoying it compared to all of the stress that I encountered while contemplating how to attack the problem. Also, I sure hope Larry tells me that some oil bolt is loose that is the culprit to all of this oil consumption in these cars. I'll take the oil pan off too. But right now, my oil pressure level is fine and I have no blow by, not in the form of choo choo train smoke coming out of the oil filler. I have only raw oil escaping as the camshaft be turning in the engine and causing the "smokeless" raw oil to escape or more accurately jump out when the oil cap is removed.

BenzDiesel

If you've checked the cylinders and they don't show any sign of ovalizing.......your compression is good.........blowby is minimal..........then, my only suggestion to you is to consider the turbo seals as the problem.

I've personally watched a 603 consume two quarts of oil within 40 miles.........with some decent white smoke out the back........but otherwise running perfectly fine.

The culprit was the turbocharger.

Take the vehicle for a drive and bring it back and remove the crossover tube. Check for oil in the tube or oil at the turbo discharge outlet. If you see oil droplets there, you've found your culprit.

yes its the darn bolts that hold the oil baffel to the block,baffel is between the crank and the oil pan.
i think i will wait to sell all my cars at once,i now have 5 of the 3.5 cars and the 4 i already finished are all running and driving.
as soon as brians blows up i will get to visit ny again,lol brian do i have to cross the 295 bridge leading to long island to get to your place??
larry perkins

Well, don't bet the farm on that one Larry. It's not going to be around much longer. In fact..........I haven't even seen it........

Yep, you'll have to do two bridges...........I-95.........then I-295.

I took the turbo off three times and finally put one on that came off of my car, BEFORE the cracked head and when the car was using ZERO oil and stayed at the top of the dip stick between oil changes. That is how I KNOW that all 603 of the 87 variety DON'T just use oil, just because it is a 87 603 and is supposed to or is expected to consume oil.

I never say never, however! But do try to diagnose my car issues in a systematic and logical and orderly manner beginning with the easiest potential solution first. I didn't want to take that head off, but am glad that I did, even if it won't stop the oil consumption. But after going down all of the easiest roads; I didn't have much choice, if I wanted to keep the car. And still might have to take it down next year. And ovaling of the cylinders, I found none and a couple of the cylinders didn't even have a trace of ring ridge and the ones that maybe did have a ridge, was barely noticeable. This is what has been or was so baffling while searching for the answers.

BenzDiesel

What is your take on the tilted piston as a cause for oil consumption? Did you find the pistons to be tilted in any of your cars and to be clear; are you saying that the LOOSE BOLTS is the ONLY culprit, when the gasket or turbo or any of the commonly THOUGHT issues aren't actually causing the problem? Correct me if I'm wrong. Is a "baffle" the oil pump connections to the block? I know all of the parts around the oil pump to include the oil pump, but don't know what a baffle is, by the name of baffle. But, I just know that I am going to take that oil pan off and check it out. My only concern is getting the gaskets to seal back up and not leak.

BenzDiesel

my experience on the 603 engine is limited to the 603.970 which is the engine known as the 3.5
if i am correct your engine is a 603.960 3.0l
these long threads would be much shorter if all would address their engine number each time they post.
the loose bolts that i have found in all 603.970 engines came from a curved plate that was installed at the lowest point of the block, it has slotted holes that allow oil to flow(and the loose bolts,actually found damage to the bottom side of a piston,it had thread imprints on the from the baffel bolts)intent is to reduce oil foaming???to my knowledge the 603.960 engine does not have an oil baffel.
do me one favor benzdiesel, start your car with the tube disconnected at the valve cover (the one that passes the blowby gasses to the intake)leave the oil filler cap on,place your thumb to block the blowby gasses and count in 1 second intervals till the engine stops.
post the results.
larry perkins

Larry, now you've got me wondering what he's got?? 603.961 or 603.970??

Maybe I got a bad 3.5, but have a good 3.0, since I do know of Mercedes Benz products going the 5000 to 6500 miles between oil changes WITHOUT using ANY oil.(this is part of a last post by benzdiesel)
sure is confusing for an old man,lol
if it is a 3.5 then i suppase i did answere part of the question, help benzdiesel.
larry perkins

Measurement at 2:30pm, 22 hours after start - #1 at 49mm or 5mm drop. The high (intake) end of the piston is no longer submerged. #2 at 49.2 or 0.2mm drop.

Given this and BenzDiesel's still not trivial oil consumption I guess it's back to the 3.0 block

Sixto
93 300SD

Well, then, if you had coolant in there, the rate of loss would be considerably faster...........

i am sure you will correct me but didnt #2 start at 43mm?
larry perkins

Ditto here. My 603.960 uses about 1 quart of Mobil-1 synthetic every 6000 miles. I change every 10kmi (with oil analysis every time) and almost never add oil between changes. The last time, at the 10kmi change interval, the level was approxiamtely 30-40% on the dipstick (with MIN=0% and MAX=100%). I've seen similar results on other 603's. A properly running 603 just does NOT use much oil, regardless of its displacement. (My 617, OTOH, was more like 2000 per quart and no, it wasn't leaking it.)

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the rate of coolant seeping away doesnt matter all that much.... as long as it takes longer than it does for coolant to seep in under pressure. so if it took 15 minutes for the cooling system to push coolant into the chamber, lets say for the sake of discussion, and it took 10 hours for it to seep away, what does it matter? if you start it with more than 1.5 cu in of coolant in there you will bend a rod. now if it were really full it prob wouldnt crank much at all and prob just wouldnt turn over.

(i have not heard of anyone experiencing this)

rememeber marshall teague said that these have bent rods sometimes with less than 100k on them. now a reasonably well cared for 603 wont have much if any wear at that point. in fact if you have one that has survived long enough to be well worn it is possible that it would be less susceptible since the coolant might flow down as fast as it can seep in. and at that point you will note it on the dipstick.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Exactly.

If, by some miracle, the cylinder is filled with coolant because it doesn't drain, and the piston comes up and attempts to compress it, the engine just stops rotating. You won't bend the rod under such a circumstance.

The only possibility is the cylinder having just a few drops more coolant than the chamber capacity. Then, the pressure in the cylinder might get high enough just at TDC to bend the rod.

The odds of this happening are miniscule.