I was losing coolant mysteriously for about a week on my 91 300TE 4Matic. When I couldn't trace it, I took it to a local shop and they found the coolant in the number six cylinder. The wagon has 130,000 miles on it, the dealer put a new head gasket in it at about 118,000 miles. So I took it back to the dealer to see if something went wrong in that job.

I was just informed that I have a cracked head. Even though they could not explain how I did that without ever overheating the wagon. Question 1: Can this happen without overheating it? I have only seen the coolant low light come on and never see the temperature rise above normal operating temp.

Question 2: What are my options here? They are recommending some used parts with year warranty on them. Then again, I had my own trusted part and it failed anyway. Should I go new OE part or used remanufactured? The quote is around $3500 with labor for the new part and obviously less for the others. I'd appreciate some guidance here. Thanks.

I've seen remanufactured heads (basically ready to be bolted onto the car) for around $1000 a while ago.

You should look into that. They will probably come with a warranty, and the labor to install it should not be too bad.

$3500 sounds about right if the dealership does it.

Check the Good MB Shops section for a bunch of good shops that can be near you.

If in souther california, Check out Mr. MB Motors in Tarzana. This is my mechanic, and he usually charges half of what the dealer charges if not less than that. :)

Alon

A cracked head is indeed rare without any evidence of trauma or abuse. Especially on an engine that is well broken in and has been driven conservatively. I would suspect the possibility that the head bolts might have been too tight, but...that also depends on where the crack actually is. Have they told you where it is? Some cracks can be welded if they do not penetrate more than one surface of a water jacket, but usually is is a better bet to replace the head. What you do from here depends on how much you want to spend. How much do you love your car and how long are you going to keep it for. If you really want to keep it, the a new or reman head is the ticket.

Been there, done that!

Last year I went through this in number six cylinder. The head was not cracked, it was corroded through. It would be worth your while to ship the head to Greg Atwell in Dallas. He will weld it up, surface, do a fresh valve job with new guides for about $550. He is EXTREMELY good and trustworthy. His phone number is (214) 358 3002. He did my head and I have put about 30,000 flawless miles on it since.

These engines come apart and go back together extremely well. Fix the head properly, put it back on and you will get many more miles of service.

The labor for removing and replacing the head should be roughly in the neighborhood of $1,000. Don't pay $3,500 for this job.

Good luck,

[Edited by LarryBible on 06-22-2001 at 07:24 AM]

I suspect I have this same problem on my '90 300 E, because i'm leaking coolant (only after long drives) and I'm getting brown sludge in my radiator.

However, no coolant appears to be entering the engine block. I'm basing this on checking the oil dipstick which I assume would show the coolant if indeed some was entering the engine.

This same exact problem was fixed by a dealer here in Houston roughly 5 years ago (replaced head) for $5k. My car now has 195k miles on it.

(shrug) I'm not paying another fortune to fix this problem if the head is cracked, and no coolant is entering the engine chamber. I'll simply continue to just add coolant at this late stage of this car's life.

Paul

(clipped from previous response)<<(shrug) I'm not paying another fortune to fix this problem if the head is cracked, and no coolant is entering the engine chamber. I'll simply continue to just add coolant at this late stage of this car's life. >>

1990 model, 195K miles is late stage of the car's life??!!:) Check out Larry's signature. This car is just broken in!! You've got another 150k to go on this one! Check out the sale price of a replacement car, comparable to this one. That may sway you to repair it.

Good luck, with whatever you decide.

I just posted in another thread that a machine shop guy told me that the M103 head is susceptible to cracks if the cam isn't bolted in properly (sequence and torque). I haven't read about anything like that in this forum so maybe it's not a real factor.

Sixto
91 300SE

Paul,
You are probably having a slightly different problem. Your head gasket has ruptured and is pumping oil into the cooling system. You should have this checked out and reapired as soon as possible. This mix creates a brown sludge that contaminates the entire cooling system and is extremely difficult to clean out.
The source of the problem is a cooling galley and an oil galley at cylinder #6. These two galleys are approx 1/2 inch appart. The gasket material in between the two galleys deteriorates over time and allows oil to seep into the cooling system creating the brown sludge you are seeing now.

Thanks for the tips so far. Okay, the latest is that I can get a remanufactured head for around 1,000 with a year warranty, $700 for a local remanufactured one with no warranty, or $2000 for a Mercedes OE. $1,000 labor. Is the Mercedes OE worth double the difference? The dealer sympathize with my expensive problem and acknowledge the Mercedes marque is having a lot of problems, especially with the newer models. This does not inspire confidence for me to ever buy another Mercedes again.

Hey thanks Chowpit, and sorry Amge55 if i'm getting this thread sidetracked on my problem.

Ok, headgasket replacement + valves (195k) on this '90 300 E, gonna be around $1200 or so, maybe more.

This light brown sludge is also leaking onto the ground, just behind the right front tire. (usually only after long drives) -- I have been replacing coolant as needed, and have had no overheating problems yet. (needle sits right at top of 80c reading as normal)

My question is, do I have a radiator leak too? Or is the sludge leak a symptom of the blown gasket as well...

Thanks guys, this forum rules =)

--Paul

Larrys absolutly right about a good shop being able to weld and redo a head at a fraction of the cost of a new one. When I worked in a shop years back we got a lot of Hondas (if I remember they were 1300 engines) that were prone to cracked heads we sent them out to a shop in Northern Ohio for welding and we never had one returned with the same problem......
William rogers......

AMGe55,

I say again, box up the head and send it to Greg Atwell, it will save you money and be absolutely as good as new.

It's really funny to hear from time to time people saying that a Benz is not made as good as it used to be. It's funny to me because I've been hearing this for the past 30 years, and the cars are getting better, not worse.

It really puzzles me to hear so many myths as they pertain to automobiles. Try a Chevy or Ford. You'll get 200,000 miles out of one if you take really good care of it and are lucky. When it comes engine time on most other cars besides a Benz, there's nothing left worth putting an engine into.

Occasionally, even a Benz will have a problem, but the difference with a Benz is that you can fix the problem and it will stay fixed, and you will have a solid car underneath you again.

Good luck,