Good Morning Guys,
You guys are way ahead of me here...but I infer from the discussion that there are variations re: tubes to air cleaner depending on engine type. My car ('85 CDT) has one black rubber hose going from top of valve cover to top of air cleaner. I don't think my vacuum pump is connected to the air cleaner.
What purpose does this hose serve? It seems to dump into a small canister within the air cleaner housing itself. None of the fittings are air tight.
My engine is original but always well taken care of and gently driven. I know from following various discussions that many (most?) diesels use a good bit of oil. My consumption is low by comparison and I assume that is not a bad thing.