Oily intake
 

I've been burning oil, and i think it's the oil separator. I've read all the posts about how the separator usually isn't the problem,

BUT, I took my throttle assembly off, looked inside the manifold and it is wet with oil inside.

Is there any way to clean the separator out? if i took it off and sprayed some brake cleaner inside would it hurt anything?

Maxwell,

If the separator is clogged with something then cleaning it will definitely help. The unit gravity drains back to the oil pan so if the drain line is not draining fast enough the oil will go somewhere. On the other hand, the oil separator may be overworked by the blow by - higher volumes of blow by make the velocity of the gasses more capable of carrying oil droplets further - which would suggest the issue is internal engine wear allowing more blow by.

It cannot hurt to clean the separator out and see what happens. If that does not work, you will have to look deeper inside the engine. Good luck, Jim

I have a simiiar problem in that I get oil pooling in my air cleaner 1982 300TDT. I opened up the seperator and it is empty-like like the inside of a tin can. Is it missing something? Would adding some course steel wool or scrub pads help it in filtering out the oil?

Both problems could also be a failing vacuum pump diaphragm . When mine started to go I also thought it was blow-by , I cleaned the inside of the filter housing and checked it after a drive and could see that the oil was coming from the vacuum pump exhaust on the top of the filter housing . Good luck :)

I have seen (with my own eyes) the drain-back tube become disconnecte from the airfilter housing. This was due to failed aircleaner mounts. The housing had bounced itself right out/off of the tube. (there is also a bracket that holds the tube in place...it can also come loose, giving the tube extra play)

I have the same 2 problems with my 240D. It "burns" and has oil in the manifold. Is the separater the little black pot by the air filter housing??!?!?!

240Demon,

Yes, that is the cyclone separator. It is kind of an inert thing, no moving parts, other than the media travelling through that it is "separating." It basically works by making the blow by gasses spin in the flow passage inside it, forcing the droplets of oil in the mix to the outside surface inside the flow passage, and then drawing, by the lower pressure in the intake, the lighter gasses out of the center of the "cylcone" that forms. The oil droplets are supposed to kind of collect and run together on the inside surface and then gravity drain to the oil pan.

If you have a restriction in the intake or a dirty air cleaner you may have a lower intake manifold pressure. This will increase the flow through the separator and may result in dragging some of the collected, liquid oil into the intake/air cleaner rather than letting it gravity drain down the tube to the oil pan.

The same is true if there is a lot of blow by, except in this case the increased differential pressure across the cyclone separator comes from the higher separator inlet pressure. I suppose the drain line could become a channel to drive blow by gasses into the separator from a second source and upset the operation of the unit.

Good luck and I hope this helps. Jim

In the case of my intake being an oily clog of goop, it was caued by the EGR valve. The inside of the intake manifold has a fairly constant 1/8-1/4" coating of crud. I still havent taken it off to clean it, but since my EGR has strangely and suddenly "stoped working" I am waiting on taking a "cleaning day" in the near future.