My wife called me at work around 4 today. She said she was driving home and saw steam coming out from the front of the car. She was about two miles from home and decided to bring it home because it wasn't overheated -yet.

When I got home I saw that the expansion nipple on the top of the radiator had blown out. There was coolant everywhere. The nipple was not broken so I reinserted it. I tugged on it and it seemed solidly connected. I refilled with MB coolant. It took over a gallon. I started the car, opened the heater and took it for a ride.

It seems to be okay. No overheating, the heater works fine. No leaks that I can see. (It took a while for the coolant to burn off).

So what's the deal? Should I expect this to happen again? Do I just need a new nipple? Is the radiator bad? Is Zeus mad?

if the item that is in the picture is what you are reffering to i would say to replace it. it is available from mercedes and is about $4. it is mercedes # 000-500-08-94. it more than likely will come out again
hope this helps
Ray
mercedessd@cox.net

Mine was leaking a bit, just a few drops. It seems the overflow line to the coolant reservoir was taught & pulling on the nipple. Sounds like a Japanese website I looked at once.

Anyway, sliding the clamps down a bit & getting just a touch of slack in the hose cured the leaking problem. That was a few months ago, no leaks since.

__________________
Norm in NJ
Next oil change at 230,000miles

I went out and bought a new expansion nipple for the radiator from Mercedes this morning ($7.70), removed the old one, and then I realized the old one was broken on the bottom. I put in the new one.

So now I want to know, where are the broken pieces? Will they do any harm in there?

i have seen them fall in and cause no harm. that is my experience with it
Ray
mercedessd@cox.net

I had a similar problem, only mine broke. Take a look at post #23 and #30:

Please Help!!! Coolant Explosion!!!

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1989 300CE Astralsilber/Schwarz
1992 300CE Schwarz/Schwarz