W124 Popped a sudden water leak, but engine wasn't overheating!
 

Hi guys,

I own a 1994 W124, it's a E280 with an M104 engine. I am new to Mercedes so I am kind of clueless as to how serious this situation is:

Today after coming back from a short drive (10 minutes going, 20 minutes parked, 10 minutes back), and as I was entering the parking, steam started appearing from the front grill. When I stopped and got out to look it was actually spouting both coolant and steam from some valve. Here is the picture of where the coolant and steam came from:

http://www.emirates-enterprise.com/f...AG0097-big.jpg

http://www.emirates-enterprise.com/f...0101-small.jpg

What exactly is it? A pressure valve / backup spout / link ....?

The funny thing is, the engine was at totally normal temperature. at 90 degrees or a hair above. Car has been running on that for months, and I usually look at the gauge and can say that it goes up and down as expected, taking a half a minute or so to edge above 40 degrees when you first start the car and resting between 85 and 95 throughout most drives.

Anyone has any idea what should be plugged in this valve/hole? Is this common? More importantly should I just go and get a replacement "cover" and put it in, marking it off to simply as a failed cover, or was this pressure abnormal and there is a problem with the cooling system I don't know about?

Sam

Sam, I have never seen that configuration on a MB radiator/cooling system. I would purchase a new Behr radiator which won't have that extra fitting & cap. Replace the thermostat when you replace the radiator.

You need this:
http://catalog.peachparts.com/ShopByVehicle.epc?q=1995-Mercedes--Benz-E320--Sedan-Cooling--System&yearid=1995%40%401995&makeid=63%40%40MERCEDES+BENZ%40%40X&modelid=6392%3ABT|5%3AED|10000022%3 AMBC|1508%40%40E320+Sedan&catid=240909%40%40Cooling+System&subcatid=240927@@Radiator+Fitting&mode=PD

It's the fitting to the hose from the radiator to the expansion tank. The short part of it is broken and fell into the radiator; it does not look like you have enough to hold it in place when the car gets hot. Easy, cheap, 1-minute fix.

Don't delay-- you can lose a lot of coolant through that outlet.

Hey Ferdman, thanks for replying.

It is perhaps the model E280 doesn't run in your country, or because the radiator is a tropical one. I got the car checked out before buying it and I was told there were no modifications to the engine or transmission. I am reluctant however to go into the expense of replacing an entire radiator or to towing the car to the dealer to get it fixed there unless it's absolutely necessary.


Thanks Eric, I am however just a bit confused by something: The part you describe and linked to seems to be right there still next to it in the photograph (check out the second one), the elbow is still attached to the hose going to the expansion tank. Are you sure this radiator has TWO? Because there is only one hose going to the expansion tank from this upper side (smaller hose is connecting them elsewhere at the bottom).


I know what you mean though about losing the coolant, the coolant puddle on the floor underneath the car is like two liters easy.

Is there a chance the radiator top has two outlets, one gets the elbow connector, while the other one has just a plug?

All W124 have the same radiator as pictured. The piece to the left of the circled area is supposed to be IN the circled area. There is only one elbow fitting, not two. You will have to remove the rest of the broken elbow piece from the radiator. As mentioned you can buy a new plastic elbow fitting for $4USD and fix it.

I have the same radiator. The part in your photo, at the end of the hose, is what's left of the L-shaped nozzle that clamps to the expansion tank hose. The other part has broken off and is now sitting somewhere inside your radiator. Just replace the whole thing with the replacement part I linked to above, and you are good to go.

Aaaaaaaaaaaaaaaaaaaaah, Gee I feel like an idiot! :P I actually thought that elbow was actually still fitted properly, and that the hole was an extra spout.

I also know what might have caused it to break, as I have been yanking at that hose multiple times while installing the plastic cover of the right headlight back after several low-beam adjustments.

Thanks a million guys.

One question though: the broken off part seems to be still attached on the inside of the opening. I guess I can push it through to fall inside the radiator, but the question is: There really isn't any problem in that part sitting inside the radiator while it's running for extended periods of time?

Sam

Sam, I feel foolish too. The perspective of your picture made it appear that the black plastic tabs that secure the elbow were metal. Plus, your description made me think you had an extra opening at the upper radiator connection.

Recommend removing the broken off piece of the overflow elbow rather than pushing it inside the radiator.

Thanks, I did just that.

Used a screw and drove it into the hole of the broken piece inside the radiator nozzle, and used pliers to pull the screw with the broken piece out. Only two prongs of the three that are used to hold it in place appear to be broken off.

http://www.emirates-enterprise.com/files/IMAG0106.jpg

Thanks for the help guys.

Sam

Keep in mind that if one part of the plastic on the radiator deteriorates and breaks, the others are probably not far behind. I would suggest looking for dry coolant streaks or visible leaks.

The normal procedure for catching the bottom part of the elbow is take off the hose and catch the bottom piece with a rag, etc. I wouldn't worry too much about the fallen pieces - lots of people are driving around with the whole bottom part in the radiator. The elbow is a known frail item - not necessarily a sign that radiator failure is imminent.

Thanks everybody.

Cheap fix indeed. 6 dollars for the elbow, 5 dollars for a PH neutral coolant concentrate to top up with water, 10 minutes of air bleeding and it's done.

I checked around for other leaks but there were none. Like I said I believe I caused the elbow fitting break when tugging at it several times while fixing back the headlight plastic cover., so I don't think there will be any other probems soon.

Cheers,

Sam