Ok, I've told my story before, but my mind still can't get past some of it understand the next step. I'll repost and update it here and maybe some kind soul out there can help me "get this".

Last April(2003), I bought this 300 SD. Has 300,000 plus. Runs very strong. THe guy I bought it from said it leaked about 1 qt every 500 miles. It had had a top end job a few years earlier. I took it for a pre purchase inspection at a reputable shop with a certified mercedes mech. They detailed some things that needed to be fixed, some possible places the oil leak was coming from, and basically told me this was a strong car, had no blowby, and I should get it. Got the engine cleaned because it was so covered, and then took it in for inspection. They did a valve job, checked for leaks, decided it was burning oil, not leaking that much. They suggested the turbo, or the rings (they checked the vaccuum, it's not that). I got pissed at them at this point, and went to someone else.

My turbo blew on the road and I had it replaced, this did not solve the problem. The new mech ( a good guy) told me I had tons of blowby and should just drive the car into the ground and keep it above the min line for the oil in the meanwhile. He replaced the valve stem guides also, as a last ditch when the new turbo didn't stop the oil consumption.

I've been trying Auto RX in it, it's not really helping that much except with the small leak on the oil filler cap. I'm on my first cleanse after my first Auto RX treatment, for 2000 miles(500 more to go), then another Auto rx round. There are some oil leaks that I maybe should try to fix, but they seem small. I've placed a drip pan under the car and only get a few drips a day. This car is in nice shap on the inside, not pristine, but good, solid, uncracked dash, ac works etc. Only tach and cruise doesn't work. Have had some electrical window gremlins lately, but I think that is the relay now (thanks to this forum).

I tried running a diesel rated oil in in,but they are too thin (unless there is a 20-50 rated C oil) so I have to stick with the 20-50 oil. I go through it so fast that I buy it by the case.

My problem is this, how can a car be so fundamentally broken yet run so strong and good? I just don't get it. A car at the end of it's life should sound and act like it. This one doesn't.

I am considering writing the "reputable shop" (the one that did the lousy prepurchase, they have a really big good reputation here) but I don't know what I would want out of them.

I am also considering contacting the seller, even though I purchased as is, because he mis represented or was mistaken about the oil usage.

And what do I do about my car? I don't have a lot of $ and losing this $2000 purchase price and $1000 in trying to get it together on bad advice is really challenging to me.

I appreciate all ideas and help. Thanks.

Your situation does not sound unusual to me. Rings can be worn and pumping oil into the cylinders without a lot of other bad symptoms. I've had it happen a couple of times on gassers and on diesels it is even more likely to happen since there are no plugs to foul.
Keep buying oil by the case on sale and keep your eye out for a used engine.

Can you describe the amount of blowby coming out of the oil fill cap with the car idling when warmed up?

__________________
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 did'nt see your previous post but I'm assuming the car is using more than a quart every 500 miles.
I dont think you would get any sastisfaction from the seller or the prebuy shop. It is a 23 year old car with 300K after all. Since it is a decent straight car it if probably worth sticking with.

The oil consumption sounds like a typical worn or gummed up oil control ring problem.
I would consider the following options.
1. drive it till it quits like mech #2 suggested plus:
2. frequent oil changes to perhaps degum the oil rings.
3. run some marvel mystery oil through it ( both in fuel and oil eng)
4. Check to make sure the 20w50 you are using is diesel grade engine oil. (personnally I'd stick with delvac, rottella, or the delo types of oil the the one that's easiest and the cheapest for you to get. Get a case of oil filters and become obssesive about oil changes maybe every 500 miles for a while to see if the rings will degum themselves)
if the above fails to achieve any results:
5. start looking for a good used engine out of a rust bucket.
6. Overhaul the engine.
7. Sell the car, but its unlikely you will recover anywhere near the $3000 you've aready put in it.

Hows is the oil pressure by the way?

hope this helps some.

__________________
Nothing in this world can take the place of persistence. Talent will not; nothing is more common than unsuccessful people with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent. The slogan "press on" has solved and always will solve the problems of the human race.
Calvin Coolidge (1872 - 1933)

Man, you have it easy...

The old motor in my 240D used to burn a quart like every 250 miles. I still drove it 12,000 miles last year and just kept the oil filled up with Delo 400 15W-40. If you keep oil in it, just drive it. And you really don't have to change your oil apart from a filter change every so often. I used to do do it about every 4-5,000 miles.

Don't worry, you aren't alone

__________________
Nick
*****
2002 Sprinter 2500 140" High Roof :

A compression test and then a leakage test will tell you the condition of the cylinders. Neither shop did that?????

__________________
You can get farther with a smile and a gun than you can with just a smile.

1984 300D
1985 300CD
1980 300SD
1993 SL500

[/i]


I've got you all beat! I LEAK 1 quart every 100 miles or less. The harder I drive makes more pressure and more oil leaks from my IP mounting gasket.

When I get that gasket replaced I won't have any more oil leaks and I hope to give bodyart27 a challenge as to how clean an OM617 can be!

greasy griddle,

I agree with the idea you should try some kind of oil ring therapy, either an additive, Marvel Mystery Oil, or a change to Mobil Delvac 1 for a few thousand miles with some good, wide open throttle driving with the engine warmed up, and see what happens. Our 1982 240D used to smoke (blue and black) and stink at start up and was hard to start in cold weather. Well, after a few thousand miles and two changes of oil using Delvac 1 it got remarkably better.

Even under full throttle (with my daughter at the wheel it is frequently at WOT in every gear) it hardly puffs any visible smoke, even at night with my headlights shining on the back of the car. I can only attribute that to better ring sealing, and I have done nothing but use Delvac 1 that could affect this (other than all that WOT driving by my daughter). By the way, this car spent its life from 105,000 miles when we bought it, until about 280,000 miles a few years ago, on Mobil 1 15W-50 (with a few changes of Castrol Syntech 5W-50 mixed in there) year round, and Delvac 1 still had a very significant effect. Much more robust additive package, very specifically for Diesel engine operation. I use it on all my cars now, including gassers.

Once you go through a few thousand miles of "therapy" you might want to check compression and do a leak down check to see what the problem is. At least at that time you can be more certain the problem is not soot clogging up the rings and preventing them from moving freely enough to do their job.

I came close to junking our 1982 240D a few years ago. It smoked as noted, got very hard to start even in the summer, and was shaking and noisy. Once started though, it ran like a champ. I discovered the engine mounts were shot, the starter was about to fall apart, and that the exhaust manifold gasket was loose. The switch to Delvac 1 was done at the same basic time as these items were fixed. It is still noisy, not nearly as bad, but 240Ds are noisy, but starts in single digit Fahrenheit temps, no longer smokes, and is much smoother.

So, don't give up until you know what is bad. Doing a compression and leak check before you give the "therapy" a chance to work may correctly identify you have a piston to cylinder seal problem, but incorrectly suggest it requires major surgery to repair. The therapy is relatively cheap (maybe $100 for a few changes of Delvac 1 with a gallon or two to top it off while you drive a few thousand miles), so give it a try. Good luck and I hope this helps, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Jim, I think you mean 2 changes, not a few. Mere mortals who don't have access to your secret source pay about $25 per gallon for Delvac 1.

But I agree with you that this is the right course to take. Amsoil and biodiesel have made a huge difference in my 240D.

__________________
Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
Chain Elongation References

I have run biodiesel in it with the idea of cleaning the engine, it LOVES it (I actually bought the car to convert to veggie oil, but I have delayed, trying to deal with the car instead), but it is really expensive to purchase, $2.70 a gallon, and I don't want those chemicals around my house for production, pets, kids, garden, etc. It runs smoother and quieter, maybe a pinch less power, but less smelly and smoky. I put it in when I can.

I have been using the Auto RX stuff, I called the guy and he told me that with this many miles on the engine, I would need to run 2 applications and 2 full rinse cycles before I could expect any improvement. It did fix the problem of the oil filler cap leaking that 2 new caps didn't fix, but that's all I notice now (in fact it is really hard to take off that cap if the car is cold, two hands and grunting required). I'm in the first rinse cycle, 300 more miles to go, and then the second application. So that will last me about 3300 more miles, and then maybe I can try the marvel oil.

I used about 6 gallons of 15-40 oil after cruising around the forum, but I ran through them SO FAST! It turned my horrible 200 miles to add a quart into 100 or less. It just seemed to run straight out of the car. However I only used the Rotella and the Delo, I haven't tried the Delvac. WHere can I get that cheap? I can try Delvac, but is there any diesel rated oil that is 20-50? That would probably be the best option.

axlechassis
The oil pressure is good, when the fuel pedal is pressed it is at 3 or higher, when you let off the fuel pedal it drops but goes back up when you go again. That gauge actually saved me when the turbo blew, I saw the pressue drop right away and was able to stop driving.

kerry edwards
I haven't checked the blowby myself, I'll go and do it at my lunch break and let you know.


How hard is it to replace an engine? What level of difficulty would folks compare it to? I have an old VW camper that I did the tune ups on and such, I've done drum brakes, and I tried to rebuild a head gasket on a jeep before with terrible results (many years ago). WOuld it be a realistic thing to think about? My mech says it's not worth paying someone to do it, and even if I got a good used engine it would cost about $2500. And then there is the other parts to consider, tranny, drive train, and all the gremlins of an older electric stuff vehicle.


Thanks to all, keep the encouragement coming. This is crazy s**t!

As Tirebiter suggested, get a leakdown test done to see where you stand. It's difficult to resolve a problem you haven't defined. Symptoms are a tail you will chase forever.

It's not difficult to replace an SD engine but it weighs considerably more than a VW engine and things like installing the injection pump and setting pump timing require specific knowledge and tools.

Sixto
95 S420
87 300SDL

I fyou decide you want an engine, I have one form my 85SD that I totaled.

It has 185,000 and was running great before the accident.

Best offer

__________________
Enough about me, how are you doing?

I've had a busy week car-wise, oil change and major oil cleaning last weekend, and then oil dripped on my shoe from inside... I'll be looking at the oil pressure gauge as soon as I fix the snapped door safety catch and broken hood release lever. Maybe there are some leaks here and there, and that's a lot of the oil vanishing situation. OOPS... I just realized thanks to the search function that the SD has an electrical oil pressure gauge. So, it's probably not leaking from there. But the car has beenhaving some delay in shut off sometimes so maybe it's the vacuum system sucking oil? HELP!!!

So, I've cleaned up the engine some and it looks like there is a good sized drip on to the compressor under the power steering pump. I think it's coming from on of those lines that goes into the radiator. What lines are these? THey have a metal fitting and rubber hose and are under the fuel filter.


Kerry edwards,
The amount of blowby is quite a bit of smoke puffing out, and oil mist on the valve cover. It doesn't seem like too, too much, I was expecting more from the mech's description. But I have nothing to compare it to. Scratch that, my friend has an 81 300D with a rebuilt engine, I'll look at that one to compare. However, any advise would be appreciated.

The more I look at this car, the more I think that the guy I bought it from was a snake. I owe him $100 dollars, but he's certainly not getting that!

Which shoe? Left would have been oil pressure guage, if mechanical. And I think you're right about it being electric in the SD.

Right shoe would have been from the key switch, indicating the shutoff diaphram is leaking and must be replaced. If you do that yourself, be sure to heed the warnings posted here about improper installation destroying the engine. That topic was just discussed today.

After you replace the shutoff device, you'll need to clean the oil of the lines and the key switch. You might need to replace some rubber connectors there as well.

The lines you're talking about in the engine bay are the oil cooler lines.

__________________
Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
Chain Elongation References

There's something in the archives about checking engine wear by covering the valve cover port that blows to the air cleaner and measuring how many seconds until the engine quits.

Sixto
95 S420
87 300SDL

You should be able to find a cheap CI-4 rated 15W-50 at a truck stop. If not, try your local oil distributors. Good luck.