grey smoke: maybe sticky rings...? (in my case)
 

Hello,

This is my first post at the forum, I’m writing from Madrid (Spain), where I live, and I own since a few months a Mercedes Benz 230E W124.

I have read a lot of posts about the high oil consumption that, by different causes, has suffered a lot of people.

Judging about what has been described here and also at other forums across a wide variety of cases, I deduce that probably I have a problem with sticky rings at the first cylinder.

A compression test recently revealed a very high value at first cylinder. If you pull out the spark plug of this cylinder, it is always bathed in oil.

Other symptoms: grey smoke only when car (and oil!) are hot and only when driving at town or quite low speed, specially (for example) when starting after a green light semaphore, when parking, or similar situation.

I have already change valve steam seals, but the improvement is almost zero. I put 15W-50 mineral Shell Helix Super and I change it regularly (it could be better 20W-50?).

Oil consumption reaches 3/4 litre any 1000Km, but it depends on the frequency that I drive at town, usually consumption stays around ½ litre.

My question is: does anybody tested one of that oil/gas additive that are advertised as carb cleaners like Marvel Mystery Oil or similar products? Rather than a fix, could cause them maybe more damage than benefits to my engine?

If you have used one of them, can you give me the name of the product and also what methodology have you used?

Thanks in advance for your help, sorry about my (poor) English and kind regards from Spain.

How many kilometers on the car? Do you have any history on the car like was it over heated? was there any major engine work? Is it auto or stick? Do you have any sort of vacuum booster pump on the engine? We don't have any 230Es over here. Is it a 4 or 6?

Peter

It seems you're indicating the valve guides were not checked or replaced. I would at least inspect the valve stems and play carefully for the #1 cylinder. New seals may not make much difference if the play is too great.

Steve

Hi again,

The car came to me by a chance (more or less): three years ago I bought a ‘89 Maserati 222 (Biturbo) at a friend’s shop, a very special car I must to say, so italian, it gave me a few great moments although it was affected by a lot of little grizzlies. At the end, few months ago, because of undetermined causes yet, the engine fused.

I made an agreement with my friend, I gave him in addition to mine, another Maserati 222 (a very old and worn away unit, but with the engine in reasonably good shape), and he let me choose one of the cars at the store at that moment.

In the interim, my first son was born, so a big sedan seemed to me a good option (my wife agreed!). Never thought at a Benz before... now I appreciate it.

This little story can explain that I don’t know almost nothing about my Benz. It is a 1986 model (I think), and it was brought from Germany to Spain in 1989 (so maybe it has run two or three “round the world”...). I don’t know anything about previous owners, big repairs, maintenance... the car runs very well, excluding the oil consumption and the grey clouds.

The 230E uses the M102 engine, four cylinder 2300 cc, 136 hp, a very popular engine here in Europe (surely because of the very expensive gas!).

This weekend I have to replace oil, I have planned to put 20w-50 but previously I will add an engine cleaner (detergent/carb dispersant), iddling ten minutes and then put the new oil. I will notify here if it helps...

And yes, probably a head total rebuild and also new rings are the only efficient fixes... but I want to save the money, if I can ;-)

Thanks for your replies.

You still never mentioned if is standard or auto tranmission. The reason I ask is that the smoke may not be coming from the engine. You may be using oil, but the smoke may be caused by a ruptured vacuum modulator on the transmission. I would consider rings last on modern engines. I would do the oil flushes first and then a valve job if the problem persists.

Peter

It has manual transmission (five gears); sorry about not answering your question.

I’m not an expert and I don’t know anything about “transmission vacuum modulator”, being a manual should I suggest to my mechanic to review this?

What I’ve been able to see is that all of the smoke come from the exhaust.

Ruptured vacuum diaghram?
 

Hi there,
I don't know details of your engine, but I used to have a 1975 280C, and when I first acquired it, it smoked a great deal, and the #1 spark plug was coated in oil. It turned out that the vacuum booster pump diaghram had a hole in it, and was pumping oil from the engine into the intake manifold, which routed all the oil to the #1 cylinder. You might check to see if your engine also has a vacuum booster pump - my problem was immediately visible by pulling the vacuum hose and noting the oil inside. The car smoked most just after going down a hill. which put more oil towards the front of the engine, I guess. I just removed the booster pump and installed a plate instead, as the pump isn't really necessary.

Cheers,
Richard Wooldridge
'82 300D/4.3 V6
Etc...