Since the water pump is the main suspect I am going to watch for coolant leak. Other than that it is pointless to guess the location of the renegade bolt, since it is nothing particular but is used in so many parts.

Thanks for all inputs.

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1996 E320 since 1/16/08, 171K miles as of Feb 2011

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1989 300CE - R.I.P. Dec 29 2007
Other MBs (sold): 1992 300E-24 - 1979 350SLC - 1984 230E - 1990 300CE