Hydraulic fan problem or not?

[smoker]

I have a 99 dsdp, with side radiator, the fan keeps getting covered with black sticky oil, I cleaned it when i got it, about two years ago, and I was under it yesterday looking at the fan, and it was covered again, is this a common thing with a dp? I see no leaks. where is the black stuff coming from?

["007"]

Its probably road grime and cleaning periodically needs to be done.
Not sure this would apply to your engine.