Proper Crank Case Ventilation with S/C Setup

ertelj · #1 (**permalink**) 11-07-2004, 10:09 PM

I just installed an RMS Stage I S/C this fall and love it. However my airfilter fell off and in the process of reinstalling noticed heavy oil flow coming out of the s/c intake tube down through the HGM and into the airfilter. I presume this is from the crank case ventilation going directly to the inlet tube without any kind of drain back into the oil pan.

Any body else experience this. I was a little uncomfortable ditching the stock cyclone system, maybe this reaffirms my fears. Any insight would be appreciated.

Complete Mods as follows: m50 manifold, Gen III exhaust, 3.5"hfm, RMS Stage I.

thks

paul e · #2 (**permalink**) 11-09-2004, 01:14 PM

Since my system was replumbed, pic attached, the hosing seems drier inside. The 1" hose coming off the valve cover which feeds the breather system is dry as a bone. Hence, youd expect the hoses it feeds to be dry as a bone. The catch can which Marco gave me is also dry. I mean, its got a film inside of it, but there is NO accumulated oil at all.

In comparison, before the replumb, the hoses were much wetter, and oil was definitely pooling inside the manifold. When you get up there in boost, ie, over 6 psi or so, Ive been told the dinan system is a bad design. Alot of people seem to feel the replumb is the correct way to do it with forced induction.

gerry_miranda · #3 (**permalink**) 11-09-2004, 08:37 PM

Can someone explain how this is plumbed. What was done to the Crank Vent going into the manifold?

ALso...under the Dinan SC discharge tube are two nipples. One for the BPV. What is the other nipple for?

paul e · #4 (**permalink**) 11-10-2004, 12:26 PM

gerry, heres a pic that someone else had posted somewhere. Where the difference is, is that the hose out of the valve cover, instead of going to the oil separator in the diagram, goes to the nipple on the intake tubing to the blower.. the nipple on he separator then is capped. The plug at #3 stays. The hose wiht the check valve in the pic is not there. This pic is very similar to the dinan system, with the listed mod about going to the intake being implemented. The thing labeled 'check valve' would be analogous to Dinans 3 way breather control valve.. ON mine, we just go directly from teh valve cover to the intake side of the blower, with an inline catch can to catch any vapors.. Ive found very little of it so far..

>>ALso...under the Dinan SC discharge tube are two nipples. One for the BPV. What is the other nipple for?<<

One for the bpv, the other I believe is for connection to the Idle Control Valve.

gerry_miranda · #5 (**permalink**) 11-10-2004, 02:58 PM

Thanks Paul

ertelj · #6 (**permalink**) 11-10-2004, 08:13 PM

Thanks Paul, what's the contraption at the end of the hose before going into the s/c inlet. Is that the catch can or some kind of oil seperator. What do you attribute the improvement to, just the larger diameter hose.

thks

paul e · #7 (**permalink**) 11-10-2004, 08:26 PM

ertelj.. what contraption.. in the photo u mean? Thats a catch can marco gave me a while ago off some compressor at his job. Seems to function decently as a catch can.. As to why things are drier now, I really have no idea. Im really not an expert on this whole crank case breather/pcv/cyclone separator field anyway. Im only reporting what others have told me whom I trust; engine experts have told me that the Dinan breather system is just plain lousy, and it gets worse the more boost you run.

GOTUBCH · #8 (**permalink**) 11-24-2004, 05:22 AM

What is the check valve for??? I have an AA supercharger kit this is vented into the intake elbow as pictured.
Thanks,
Damien

GOTUBCH · #9 (**permalink**) 11-24-2004, 05:25 AM

OK I worded that wrong my check value seems to of gone bad. Is it really needed?? Currently I have a barbed nipple attaching the hoses together.

paul e · #10 (**permalink**) 11-24-2004, 07:02 AM

what check valve? Can u describe it a little more??

GOTUBCH · #11 (**permalink**) 11-24-2004, 09:12 AM

In the diagram above there is a check valve that is pictured between the intake of the blower and the top of the valve cover for ventilation. Mine appears to of gone bad and I took it out car seems to run good do I need this check valve?
Thanks,
Damien

Adriano · #12 (**permalink**) 11-24-2004, 09:26 AM

Once again Paul, thank you for your vast SC knowlege. I'm glad to learn this before I install my ESS.

paul e · #13 (**permalink**) 11-24-2004, 09:54 AM

>>In the diagram above there is a check valve that is pictured between the intake of the blower and the top of the valve cover for ventilation.<<

Ok.. i see it, over on the left. Keep in mind this is a modified redo of what looks to be an oe ETK sketch, with someone's intended mod being shown. On the Dinan system, for instance, the number '1' in the sketch is the location of their 'Breather Control Valve'. It is a valve which is run by manifold pressure. Under vacuum, the valve is in a position where the vapors follow the OE path down to the cyclone separator; under boost, the valve is repositioned, and the vapors flow directly into the intake side of the blower, for recirculation.

I guess the 'check valve' in the sketch would be for the purpose of making sure the hose its in only Exits air, and does not intake it. But, even in the implementation pictured, why would it be needed? ie, doesnt air only flow OUT of the valve cover, both in Vacuum and in booste? And if thats true, why would you ever need a check valve there? I dont know what his purpose was. Actually, the pictured system looks Very similar to the Dinan system, if you make one simple change; take the hose that goes from #1 to whats listed as 'vented to atmosphere', and route it to the intake side of the blower, as he indicates hes going to. Once thats done, and #1 is a 'breather control valve' then its the same as the Dinan pcv system.