When I swapped to the Hahn intake I noticed a fair amount of oil in the stock accordian intake elbow and residue in the charge pipes. After closer inspection I realized the oil was coming from the breather which goes from the passenger rear of the valve cover to the inlet of the compressor housing.

For those who don't know, the other breather which comes off the middle rear of the valve cover to the intake is the fresh air intake ONLY. That black dingus you snap onto your intake is the PCV valve. Its a one way check valve flowing towards the valve cover, and it appears to be a pretty good valve. I hit it with 5-10psi of shop air and it held. So no reason to futz around with it unless you want two catch can draws, which on a higher boost/hp car isn't a horrible idea.

Anyway, back to the task at hand. I'm really not a fan on oil in my intake tract, or at least I often like to stop as much of it as I can. I think this is particularly important on direct injected cars for obvious reasons.

I had intentions of fabricating some elaborate AN setup using the proper 3/8" Russell fuel quick connects etc, but the budget just can't handle that right now. Here is my $20.00 catch can setup. Note that I have clamps on them now, which I would reccomend since the valve cover and turbo inlet arent barbed.

Also if you're wondering why I replaced the braided line from the PCV -> valve cover, its because I never could get that Hahn intake positioned in a way that didn't keep pulling the PCV off. So I said hell with it and went to a rubber hose for now and what do ya know, its staying put. The rest of you should leave that line alone unless you're having similar issues.











Essentially I removed all of the braided breather lines, which was a major pain in the ass not destroying them. I had to improvise some tools and looking back I might've just destroyed them had I known it would take 45 minutes. Why GM didn't allow enough space on each one for the standard fuel disconnect tools, who knows. Obviously I salvaged the fitting off the turbo inlet and the PCV valve without damage.

I then made a little aluminum bracket for my $12 air compressor water separator. I've used these in the past for this use, and they work pretty decent really. I found a nice one at Lowes that even had a copper strainer. Not the usual "stone" style like a fish tank bubbler thing, so I think it should stay unclogged. I'll keep my eye on it though. The only thing about the Lowes separator was it had a positive pressure valve on it for draining. So I removed that and sealed it with a nut, bolt and two o-rings.

I installed 2 x 1/4" NPT 90* elbows to some 1/4 NPT to 3/8" barb fittings. This bracket is not my best metal fabriation project and I'll make some improvments on it this week. More than anything It needs cut straighter and some support gussets TIG welded onto it.

Finally I ran some 3/8" fuel hose from the valve cover to the IN port on the separator, and connected the turbo inlet to the OUT port.

As you can see in one of the pictures, already starting to trap some water/oil milky ness yum yum.

So this was a rambling post, but if you also dislike oil in your intake... you might consider doing this too. You won't stop it all, but some is better than none.

 

That should trap it alright.

You need a hotside charge pipe!

 

I need a raise! Or my family to quit eating, one of the two

That Spec clutch + rotated mounts kinda deflated the toy budget for a bit.

 

Very interesting, I may have to give this a try because I too noticed the oily residue inside the stock intake piece.

 

Ya those fittings are major pain, i think i had upto 3 screw drivers jammed into the 45 degree fitting trying to get that clip inside loose. Otherwise lookin good...

 

a small piece of cardboard from the case on a 12 pack of soda is a good cheap tool to use on those fittings a lot, and you can customize it to whatever size is required for the application.

 

instead of a water separator, what else can be used? maybe a filter? like a clear plastic fuel filter?

 

Yah you could use a filter, just keep in mind the oil will reduce the flow accross the medium pretty fast. You don't want to kill the engines ability to breathe or you'll start pushing oil out of places you don't like.

I've always had good luck with water separators, and they're cheap too. Plus you can clean them out every 2-3 weeks in a few seconds.

Use whatever you have handy, just avoid those unbaffled catch cans all over ebay.

 

OK thanks for the info. Bychance where did you get your separator ? can i do this without an after market intake? i just have the factory air box mod on mine.

haha nvm i just need to read more. thanks

 

so you stated in the first post that the pcv valve is a one way valve flowing to the valve cover. I thought the opposite and to back that up than how would you get oil into your intake if there can be no flow that way?

 

The braided line on the back of the valve cover that runs to the inlet side of the turbo has no check valve and is the source of oil in the intake. You cannot put a check valve in line on that line (Don't even think about it) because then the crankcase cannot vent pressure properly (the other line allows air into the case but not out) and you will have a host of problems.

 

^^^so are you saying this is a bad idea to do? or just what he said? what would you recommend for catch can then?

 

What Terminator2 is saying: don't block off that rear breather line unless you like dip sticks popping out, oil pushing past front/rear main seals, o-rings, oil drainage issues and all the other wonderful things that come along with excessive positive crank case pressure

What I've done is not change how the stock system works, I've just put an impovised catch can in line.

I'll take a picture when I get a chance, but I'm already collecting a pretty good amount of oil and I've only driven the car 30 miles. Actually a fairly shocking amount of oil, but then again the amount of boost some of us run its not too surprising I guess.

 

so what if i go by one of those cheap ebay one with the muti piece setup? disassemble it and put some pot scrubber in it as a baffle? i've been searching online and a lot of subi owner went this route. cheap muti piece catch can, and stuff some metal pot scrubber in the bottom of the catch can.

 

I'd be very careful on what pot scrubber material you use, but it will work yes. If you get bored look around on the SRT4 forums and you'll find a nice baffle setup a guy made from a knock-off Greddy can. The issue is you need to direct the airflow though the baffle/medium, not just put in the srubber stuff to get as much gunk as possible.

 

so how and where i would put the scrubber? bottom of the catch can?

like put a hose inside the inlet of the can? and not put a hose to the inside of the outlet hose?

 

Yep you got it. The line on the intake is really a negative crankcase vent line only because of the one way check valve and the one comming out of the rear of the valvecover to the turbo can be either a positive or negative vent depending on whether you are in boost or vac.

 

http://www.**************/forums/f75...ch-can-488360/

Read that.

EDIT: Thats very annoying, i cant link to srtforums . com

 

okay forget about those ebay cheap can, its just a bit too big to put in the turbo cobalt in my taste. i'm gonna run the oil/air separtor from homedepot or lowes. now i have some questions, does it matter what separator i get? remove the filter or not from the separator? flow direction separator? which directions? because the line from the manifold to the turbo inlet has no check valve, thanks.

 

1.) Not really, I got what was on sale @ Lowes and it happened to have that copperish filter.

2.) Try leaving the filter at first, but it will likely get gunked up pretty quick. So far mines been okay but I need to find a different baffle eventually. When I drain the bulb I clean our the filter real good with brake cleaner.

3.) Put the hose from the valve cover to the IN on the separator and the OUT to the turbocharger.

 

thanks a lot gimpster

 

wow just spent over a half hour using different materials around the house to try to pop that hose off... including cardboard from soda box, plastic from a pop bottle top, and even a brass curtain rod.. cant get that sucker unhooked! went to 2 garages and both said they have fuel line disconnects but nothing that small to get in between and said to go to gm.. and quite frankly i cant stand to gm.. and have them ask stupid questions about why i want it done and charge me 50.00 to do it.. is there any other way to get this done? i have my catch can ready to install just need that stupid braided line off..

 

I've been thinking about picking this up, but I need to figure out a way to plumb the drain back into the system. Ideally without having to get something welded in.

http://www.mann-hummel.com/group/upl...BCHACUaaBi.pdf

This is the same air oil separator that Lingenfelter uses.

 

http://www.aaronreedbaker.com/oil.html

simple and easy to make, and can be simplified more

and i know its honda, but http://www.honda-tech.com/showthread.php?t=1778967, will give you some good ideas to start

 

I helped a guy not too long ago who also couldnt get his off, no matter what we tried.

Ended up using a rotary wheel on the dremel and split it down the middle. Came off then