Have the same hole in my '86 valve cover, and seem to be constantly wiping the little bit of oil that escapes from it. Have wondered what it is all about, but have not had the need to take the valve cover off yet. I am going to seal it in some form or fashion when I take it off and see what is going on in there.

Bill

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Bill Brune

86 190D 2.5 5spd 314k
87 190DT 150k
87 300SDL 357k
95 E300D 115k
02 Jetta TDI 90k
99 Subaru Legacy