How serious a problem might I be facing? I have a 1992 500SL. There is a fair amount of white residue that begins at the hose/clamp connection on the driver's side of the radiator and trails all the way down the radiator. That residue has been there for quite some time but does not seem to be increasing. Today, I lifted the hood to check the fluids and noticed an audible hissing and slight amount of fluid bubbling from a connector(?) on the top of the radiator just above the hose. How serious might this be(?).Thanks. JR

It sounds like it's time to replace that hose and/or connector - much cheaper than what might happen if you lose coolant. Can someone (...Benzmac) say whether these cars have the rad neck breakage problem like so many other MBs?

Be carefull here, plastic header tanks have a tendency to break at the flange of the top radiator hose.
Right under the hose clamp.

So the incidence of running the cooling sys dry is great. But ,of course we always watch our instruments.

Have it seen to, priority ONE.

JR:

That white residue is the tell-tale fluid that MB puts into their coolant for just the purpose that you have experienced. It is a tell-tale for leaking components in your cooling system. So consider yourself lucky that they do this, because otherwise you might never have known that you were leaking.

I would concur strongly that you attend to this/these leaks as soon as possible. "Frying" an engine due to loss of coolant is never inexpensive (double negative intended)! You are talking major bucks (new head, new pistons, new valves, etc. etc.)....Andras

You need to have a tech take off the upper hose and see if the radiator has a reinforced neck. If so, just replace the hose and the clamps. (clamps are a must!!)

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Benzmac:
1981 280GE SWB
1987 16V
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
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