Hi guys and gals,

As of late, my car has been "burning" alot of oil. Between oil changes it eats up about 3.5 quarts of oil (horrible). The car is mainly driven on the highway. The other day when I was on the freeway doing about 60mph, I downshifted to "2", got up to about 75mph and then kicked it back up to "D". As soon as the tranny upshifted into "D" I noticed in my rear view mirror a bunch of black smoke. I think it time to change the seals on this badboy. What I dont understand is there is absolutely no smoke when I start the car up. Although the belly pan seems to be alittle saturated with some oil gunk, I think the problem is the valve seals. I've noticed also that If I smash the pedal from a dead start, say at a red light, once the tranny shifts into 2nd gear there is a huge cloud of black smoke. I was wondering what you guys think I should do?? Should I opt only for the seals, or do the complete valve job? I was quoted $1200 for the entire valve job, I've yet to ask a shop on a price for only the seals. If I only do the seals, will the consumption go away or just reduce it? The car runs like a champ by the way, great acceleration, etc. I change the oil every 3k miles using Castrol GTX 10W-40, and a new filter. It currently has 120k miles on it. Im waiting to hear from the techs on this..

__________________
Agron
1989 300E ("E 300"-Badged)
Monotoned Astral Silver w/ rear lid deck panel
97 Style Replica E420 Rims 205/55/16
Euro Headlights
Clear Corners
94/95 Taillights
Black Grille Insert
Chrome Exhaust Tips
20% Tint
Pioneer Sound system w/ Sub-enclosure and CD-changer

Agron80,

Have you done a compression check? I would suggest doing a compression check. If the compression is okay, you might get by with only the valve seals. If it is low, squirt oil in the cylinders and recheck compression. If it comes up then it is rings and tells you that you need more than a valve job, if it doesn't come up, then the problem is the valves and you need to do a complete valve job.

I recently had head problems on my M103 engine, removed the head and took it to a machinist who is very experienced with these heads. The result was outstanding, and I was very impressed regarding how well this head comes off and goes back on. There are many cars these days that are made to throw away after they are used up, this engine is not one of them. These engines respond well to head work, and they do not have connectors that crumble when you try to remove them.

My engine at 170,000 miles still showed crosshatch on the cylinder walls, I would expect that this is what you will find inside yours providing it has had adequate oil changes.

Best of luck,

Add to Larry.

I have not ever had to do the bottom end on a 103 engine. The question is whether or not you plan on keeping the car. IF you will keep it, just go ahead and do the valve job. Be sure that they use OE guides and seals. The rest is up for debate.

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Benzmac:
Donnie Drummonds
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS

Older 300E models burn oil?

Well, yes mine sure does. I have a question along these lines. I have 218K on mine('86) and it consumes about 2.5 to 3 qts. every 3000 miles. I have no problem adding oil between changes, however the plugs look pretty black and oily after 10K or so. Replacing the plugs is no big deal either.
So here is the question: If I am fine with just adding between changes, is the engine ok with it also? Am I damaging the oxygen sensor or catalytic converters?

Adding oil to the engine frequently keeps you "tuned in" to other problems that may arise under the hood. Am I seeing a silver lining when there is none?

-Blake

My 190E 2.6 uses 2-1/2 to 3 quarts every 3000 miles and last oil change I switched to Valvoline Max-life for high milage engines. The results were pretty good. I was down a quart after 1700 miles and now it's about 2500 and I havent't checked the oil yet. My oil light would come on before at 1400 miles and I would be down a quart and a half usually. I'm going to use the Valvoline again at the next oil change. Willdo the valve seals this summer. It has gotton cold here in Chicago.
Note: Tried the LUBRO MOlY OIL SAVER and the results were not measurable while the Valvoline was.

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1990 190E 2.6
1996 Grand Voyager 3.3
1985 Mustang GT 5.0 5 SPD
1982 Suzuki GS 750T

Sorry it took so long to reply but I just walked in. Im in college and finals/presentations are due this week (Golly, its 2:15am). Anyways, I will first get the compression test done as Larry suggested. By the way Larry, what is a compression check?? What goes into a compression check? Is this some extensive type of labor for mechanics to take more of your money? I stopped in my local MB dealership today and spoke to a service manager about the problem i've indicated above--man, what an a**hole he was. I told him that I wanted a price quote on just changing the seals, and he said "well, your looking around $900 son". I said, why does it cost so much when changing the seals doesnt require removing the head (thanks MBshop). He said "the head must come off for seals--we dont do that kind of monkey business". I kept pleading with them that you can change valve seals without removing the head. Even his fellow buddies jumped in trying to defend him. I started throwing some "verbal javelins" or "technical stuff" at em, and they started to feel nervous. They though I was just some dumb youngen with no idea about cars. When I would use terms as "M103" or M104" they didnt even know what I was talking about. In my opinion, I think they were even suprised that I knew what a valve job was. Basically they were all a bunch of greasy fat guys in cheap suits. When he said if i wanted to book an appointment, I clearly told him no thanks pal, and I walked outta there. But again, once finals are over, I will take her to my independent tech, and do compression check. If compression is fine, the seals are going in, if the compression is bad on some of the cylinders, Im gonna have to make a huge decision. I have to thank everyone who enlightened me further on this subject. By owning this 300E, im beginning to learn alot about the automotive industry and what type of crooks are in it. God bless MBshop

Sorry for ranting...i'm tired

__________________
Agron
1989 300E ("E 300"-Badged)
Monotoned Astral Silver w/ rear lid deck panel
97 Style Replica E420 Rims 205/55/16
Euro Headlights
Clear Corners
94/95 Taillights
Black Grille Insert
Chrome Exhaust Tips
20% Tint
Pioneer Sound system w/ Sub-enclosure and CD-changer

Hang on a second everyone. Yes, these motors are known for needing valve stem seals; no doubt about that. However, Agron80 indicated BLACK smoke being emitted from the tailpipe, not the blue tinted smoke correlating with oil burning. Black smoke is indicative of an excessively rich fuel mixture. Perhaps there is a mixture problem with his car in addition to its needing stem seals.

Yeah, I am with you. Black smoke = too rich fuel mixture. If your valve seals were bad, you would get bluish smoke on startup. If you get bluish smoke on acceleration, it is more than likely rings. Have your exhaust gasses checked. Check the plugs to see if they are oily. If the car is running good, I doubt you will find oil on the plugs, as they do tend to foul out and cause running problems when there is an oil problem.

Yeah, I didn't catch the "black" either. You need to find a good trustworthy independent shop.

However, if you are taking a lot of oil, there is a reason for that which is probably not directly related.

Good luck,