FWIW ,
My 1984 300CD has the earlier single O-Ring and aluminum crush washer typ and yes , it weeps .
To - day I was in a Pick-A-Part Junk yard that had several 300SD's , the 1983 and 1984 both had the upgraded filter head and double O-Ring bolt so I bought both and am off to try to find the correct Mercedes O-Ring part # as this weeping drives me nuts and the Diesel Fuel attacks and destroys every thing rubber and plastic it touches like my new motor mounts , sway bar bushings , ball joints (the boots) , shock bushings , on and on....
THANK YOU for this thread ! .
Only one lonely W-123 Sedan in the biggest Junk Yard in Sun Valley , my how times have changed
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