Engine Oil Goes to Intake Via Oil Air Separator

a filter?

Without knowing anymore than the very vague details you have provided, I'm going to suggest that you require an engine overhaul. Sounds like your piston rings are worn causing blow by.

I'd suggest you get a local mechanic to look at it.

Alternatively, just top the oil up every morning and check the level at meal breaks.

It won't save the motor but may let you finish the job if it is near completion.

Don't open the oil fill pipe if the engine is running.

What does Liebherr USA have to say about it?

Look here:Product information.

Or call them. Or call a service tech.

Did you have cylinder compression tests? Leaking combustion gasses in the crankcase reduces oil separator's efficiency, and this is one of the normal paths of excessive oil consumption on worn engines. Idle 710 cap checks are not very revealing. S.M.

You have a serious crankcase pressure problem, could be piston rings broke allowing pressure past piston into crankcase then back up the breather pipe into the inlet manifold. It's a heads off job, get a compression test done to confirm first, you may be lucky and it just be a head gasket blown either way it's heads off.

Bazzer

Probably blow by. Re-ring when convenient. Till then add oil as needed.

I'm not familiar with your particular engine, but i have seen this problem caused by a stuck positive crankcase ventilation valve (PCV.) VW diesel engines have pcv valves, when clogged or struck closed crankcase pressure increases forcing oil up through the pcv system into the breather. I hope this is helpful. PCV valves are cheap compared to a ring or head job!

Try replacing the air intake filter first, probably it is clogged up.

Yet another question where the one asking does not know about the Good Answer Rules.

OTOH he found his way here to ask his question

What am I getting at?

Hell.I don't know.

my apology...

Many thanks for your nice ideas. However, do I need to reroute the small pipe from air oil separator into ambient exposure to avoid suction of unfiltered oil by the turbocharger?

Actually, rerouting the pipe, is a very bad thing to do to your oil. The "vacuum" removes from oil the humidity and the light hydrocarbons, (perfect or less than perfect combustion products). Stopping that, the oil will soon become a very good cutting fluid and chip removal enhancer inside your engine. S.M.

Does it mean oil entry to engine via turbochager is not as bad as rerouting to ambient exposure?

In my opinion an engine with such a problem is inoperable. Of course the criterion is your actual oil consumption. If you have an exhaust oxidising catalytic converter (most diesels nowadays do) it will be irreversibly damaged from overheating, deposits from burned oil will form all over, and there's always the possibility of a runaway and self-destruction or of oil starvation when oil is burned out and you fail to refill on time. I'd definitely re-ring. S.M.

Thanks bro. This is the best advice so far.

would like to know what exactly happened to bring about a condition like this.

Simplemind had already said of what will happen with the condition like this.