1994 E320 Wagon, 118,000 miles. My first MB.

I knew the headgasket was bad but the rest of the car seems nice. The price was low. The car is not overheating, but the coolant in the overflow tank looks like a chocolate milkshake. The seller knocked $3000 off his price when he saw it. The engine oil looks clean on the dipstick. There is no white smoke from the tailpipe.

I figure that I want to do it myself. I've done one headgasket before - on a V6 Alfa. (I did a good job). But that car used a belt rather than a timing chain. But I'm not in a hurry. I have a place to work and I can take my time.

Can someone please direct me to a good set of step-by-step instructions? I saw the ones on this site written in Russian. The pictures were nice, but I would have to ask my grandfather to translate from the Russian. And he's dead.

From my reading on this great site, I have decided to also replace the water pump and belt tensioner at the same time and to clean out the EGR tube. And I'll have the head milled and new valve seals put in.

I guess that I could do the chain/tensioner/rails too, does anyone know how much more time/money that would add?

And what are the best places for parts? How can I be sure that I get the updated head gasket?

Do you think I should drive it home? I live about 15 miles from the seller. I could have it towed. But he just drove it back from Niagara Falls to the midwest so who knows how many miles he drove it with the chocolate shake mixing around. What is the best thing to use to flush everything out?

I'll keep everyone informed as I progress and I'll do my own write-up with pictures and post it when I'm through.

Thanks,

Charles

 

http://www.mercedesshop.com/shopforum/index.php3

 

The best place is http://www.autohausaz.com . Low prices and great service.

 

Before I would take the engine apart I would check further to make sure it is the head. If the oil looks good and has no coolant content, just drain it and check again, or check the oil filler cap. If it shows a brownish foamy slush it may be coming from a worn head gasket. If the coolant just looks like chocolate milkshake, the previous owner may just never removed over 10 years. Maybe you just need a good radiator flushing. If the coolant level stays okay, why should the head being a problem? The valve seals are a possible problem for the years upto 90/91, since they were made of rubber. Eversince then a new material composition was used and the normally dont fail. You can check the plugs, if they are "foul" (lots of black oily residue), it may call for a valves seals change, if not just leave them alone.
I have 2 W124 both well over 200kMiles and never changed a gasket, or a waterpump, or anything significant, and both still running great.
If you want to swap the timing chain(s) you need to take the engine out to get to it. Or atleast you have to lower the engine, which asks for taking off anything attached and underneath the engine. I can tell you my almost 20 y driving experience with MB tought me the W124 inline 6 are just the toughest engines which like to be left alone, as long as possible.

 

If the oil looks fine and doesn't have a milkshake look to it, then you can safely drive it home.

Bamberger is correct about the coolant flush. I just want to add that it's advised to use some type of non-chlorinated detergent during the flush to clean the sludge from the system. Dishwashing soap would work. The Prestone flush products aren't appropriate in this case since they're formulated to act on corrosion deposits.

 

http://www.continentalimports.com/ser_ic100345.html

 

Thanks for the hope Bamberger. I will try a flush first. Becasuse if there IS a leak in the headgasket, or a crack in the head or the block which causes the oil to move to the coolant jacket when there is oil pressure, then why doesen't the coolant move to the oil when the motor is shut down? The coolant should have about 15lbs of pressure after the engine is off. If this is correct, what I have is a very dirty cooling system, or possibly a transmission cooler leak.

Has anyone seen an exception to the above theory?

 

If oil leaks into the coolant circuit you should also see the oil being on top in the coolant reservoir, as oil is lighter than water. As you said you should finding water also in the oil. As I proposed check the oil filler cap for oil/water foam. Looks like a the cream on top of a cappucino (but tastes different :-)
Your idea concerning transmission cooler leak, there might be something to it. I have seen such a case somewhere in this forum, but as I recall it was a W107 (SL very old). I dont know how this was functioning, since both of my cars are manual shift.

 

step-by-step instructions http://www.gdtm.ru/M104/M104.htm

The translator http://www.translate.ru/

 

I drove it for a few days and it seems to me that the oil is coming back into the coolant. I learned that this CAN happen to the M104. The galleys in the rear of the head are quite close. When the car runs, the oil can drip into the coolant without the coolant coming back into the oil.

The car does have 118K and the original headgasket. So, I figure, why not fix it now, before it starts to overheat or before the oil does get contaminated and then the bottom end is damaged?

But I'm not going to do it myself this time because the head it too heavy. I'm going to pay a MB dealership to do the following:

-headgasket/ upper timing cover
-valve seals
-timing chain, upper chain rail and chain tensioner
-replace crankshaft seal and reseal lower timing cover
-waterpump
-serpentine belt tensioner/belt
-all new hoses including rear heater hoses
-flush system (again)

The estimate is $1800. The shop thinks they can stay close to this price. We shall see. I took the car to a couple of Bosch authorized service houses and they both were more than the dealership. Most of them refuse to just do a headgasket. They want to send the head out for a valve job for an extra $850. Also, the dealer gives a 12 month warranty and Bosch only 90 days.

I know this seems like a lot of money, but I took money off the price of the car when I bought it knowing that I would have to fix it. I paid $2250. So when it is over, I'll have paid about $4050. The evaporator was done last year by the previous owner. It cost him $4900. The wiring harness may still be a problem, but everything else works on the car right now. Perhaps we can do a wiring harnass group buy?

Even if I have to put in another $1000 over the next year, the car is still worth it. It drives very well, is safe and practical. I also think it will hold it's value if I take care of it. I would have paid more if the car didn't need all the work. But there aren't too many W124 Wagons here in Saint Louis and the one's on EBAY may not be any better. I think a nice wagon in good shape with all the fixes should be worth at least $7500. And at that price it is a much nicer car than a used 1996 Honda or Toyota. When the Benz is fixed, I will give it to my wife to drive. We have two kids. I like it better than an SUV or minivan.

My other car is a 1997 SAAB 9000CSE. I love it and it has been great. Very reliable and quite fast. But it has a much more jarring ride than the E320 and the handling is more twitchy because it is FWD and turbo. There is some torque steer. Also, it is a manual and my wife wants an automatic.

If the E320 lasts me four or five years without serious stuff after this, I will be very happy. Once it is fixed up, I don't mind spending $500 per year on maintenance/repair. I guess I'll see if that is possible.

Any guesses?