sorry to come in to this thread, but I seem to have the same problem w/ my '94 S500 cpe (119.970), ticking from one lifter on right side of engine.
Read the MB Service Bulletin issued in early '95 re oil feed tubes and they say to replace them. They now have a newer/better part.
Had my valve cover off and all tubes LOOKED ok (not broken) but did not remove and inspect them. Can these tubes plug?
Regards . . . . JimF
'94 S500 Cpe
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