Vehicle in question is a 1990 245 with around 250k miles (odometer stopped working a year ago)

So I am replacing my leaky front cam seal. Following posted advice about PCV clogs leading to leaking seals, I also swapped out the flame trap, which wasn't clogged, checked the small vac line (open) to the brass nipple at the intake manifold (which was open but had quite a bit of gunk in it, cleaned and reinstalled). The oil trap scares me. Does being able to blow through the hose to the oil trap, with the oil filler cap off, indicate an unclogged system?

I had a bit of a mess along the front of the engine, so I took off the timing belt and rear timing belt covers, along with the intermediate and crank sprockets, so I would have an easier time cleaning up the seeped oil (some of which wound up on the year-old alternator and upper donut seal of the two year old waterpump). The timing belt (replaced last year) did not show any signs of oil, but will be replaced.

There was a fine powder of what looked like rust on the intermediate shaft seal. There was no sign of this sort of rust anywhere else. Any ideas what might have caused this? Rust in this area seems bizzare since there was a fine film of oil everywhere else surrounding the int. seal.

Thanks for your help,

Ian