Diesel Crankcase venting

[team karst]

Anyone know how the old school crankcase venting is done? I have VP2030. Not obvious to me and ive done valve adj, oil changes, rw pump swaps, HE exchanger r&r, starter swaps etc.
Maybe sent directly into air induction?

[glenn.225]

yes

The old ones just have a pipe from the valve cover to atmosphere, most looked like an upside down J. Might have a metal screen in there.

Some of the less old ones, vented to the intake/air cleaner.


Edit: Not sure on your engine, actually had a look at some pictures of my Volvo 2001 and I don't see one either. will have a good look tomorrow when at boat.

[slugsgomoo]

my lehman went from a PCV that had hoses to the air intakes, and it was always pretty dirty. I've re-done mine more like my racecar, and it's been working beautifully.

I come off the valve cover, and go into a baffled, sealed catch can. Then, that can has a draw line that goes to the air intakes on the engine. You still get the suction effect on the VC, but the oil vapors end up in the catch can which can be drained periodically. Way less mess, which is nice.

[team karst]

PCV needs engine vacuum to make positive flow correct? But diesels dont make vacuum.

[team karst]

I remember now on the littleVP’s. During the valve adjustment, not only the valve train was exposed but also the intake runners. I suspect there is a connection, tho each section had its own o ring seal. I didnt see anything that looked dirty up there

[slugsgomoo]

Originally Posted by team karst

PCV needs engine vacuum to make positive flow correct? But diesels dont make vacuum.

you're right, it's probably not a PCV valve- that said, when you draw off the aircleaner, you're definitely going to see some vacuum (even if it's not a ton).

I know that at 36psi of boost on my car I can collapse a huge K&N cone filter - The diesel is nothing like that, but I can definitely feel suction at the intake there, and it seems to do a good job pulling nasties into the catch can.