The 'cyclone' oil separator is in the M62 engine. Your N62 engine has a simple valve built into the head. There's no cyclone underneath.
The correct way to clean the valve is to remove the valve cover. I was lazy and cleaned mine by blowing carb cleaner down the hole and into the engine. Then I immediately changed the oil. This is NOT the correct way.
Here's more info with a good explanation of failures:
https://www.meeknet.co.uk/e31/BMW_M6...entilation.htm
Underside of the valve cover: