Don't feel bad.....1987 300SDL came in on the hook with siezed engine.
Stripped it down and found a small bronze coloured ...what could only be described as a melted piece of bushing.....gone into the oil pump and snapped oil pump drive chain..
Would never have happened if the quality control person in the oil pump department had been paying attention back in 1986 !
Found a gap in the pick-up screen where the mesh had been pressed into a dome to fit in the pick up snout....the preceedure had opened up the meshing allowing the piece through....after who knows when it got into the engine, although I never found where this little bronze piece came from.
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