Hello all,

I have searched coolant leak threads ad nauseam but either I'm missing something obvious or this has not been previously covered (at least to the level of detail I was hoping for).

My 1995 E300D has a small coolant leak (about a shotglass full leaks out overnight) that I have traced to the coolant pump housing. Things are fairly cramped up there, but crawling under the car and looking up, I can see that the bolt between the two oil-water heat exchanger hoses (not the bolt holding the supports for those hoses, but the bolt on the pump housing itself) is very wet. When I wipe this bolt off, coolant reappars realtively quickly. I cannot trace the leak anywhere from there - it may very well be coming from higher up, but as far as I can tell, everything above this bolt is dry. There is quite a bit of the white crud around the bolt head and the immediately surrounding area has collected some of this as well.

I have attached a picture from the manual with the bolt that I'm talking about colored in red.

Has anyone ever experienced anything like this? Is this your standard water pump leak? It looks to me like something on the water pump HOUSING is leaking?

Any input or suggestions you may have would be greatly appreciated.

Thank you in advance for you time and efforts,
-Vlad
'95 E300D
'01 SLK 320 (6sp)

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