Installing an Oil Catch Can
 

Thanks to CatManHHR, he PMed me while I was still in the build process. He had asked if I'd thought about running an oil catch can. I did not! After doing a whole mess of research, I didn't see any reason not to have one.

Let me start out by saying, catch cans in general are a confusing subject. Not that they are hard to understand, but the threads associated are usually long and full of questions. People will argue that there is no need or that we have defeated the engineers purpose of the pcv system.

I'm not sure either way, what I do know is when I pulled my intake and tubing from the gen 2 everything was covered in oil(IC,Charge pipes, manifold, etc). There was an actual pool of oil in the intake itself. I know that isn't suppose to be there.

Oil in the air supply causes all kinds of problems. It builds up on valves, turbo housings, intercoolers, everything! It's oil. It also lowers your A/F readings and can cause detonation. None of that is good, so why NOT have a catch can?

The purpose of a catch can is to filter the oil/air mix from the Positive Crankcase Ventalation (PCV) system. Engines build up excess pressure in their crankcases, especially turbocharged ones. The pressure is relieved via intake airflow through the pcv valve.

The valve itself is located on the braided stainless hose that runs from the center/rear of the valve cover. "Someone please chime in if I'm incorrect, my setup is no longer stock. I've got the Gen2 75% apart, going by memory!". It's removed with a fuel line disconnect tool. A simple test to see if it's functional is to blow through it. It should only let air through in one direction. Mine was working, still flooded with oil...

So what I've got now is a Mishimoto Baffled Oil Catch Can, there could be a whole other thread on what can to buy. They are very simple and could easily be DIYed if you so choose (made one for my friends Focus, for about $20 bucks! ). A word of warning, like everything else, you get what you pay for. The Mishimoto can cost me about $250 +some for fittings and hoses. That said, is definitely a quality piece. Billet aluminum, 30 micron brass filter. The box it comes in its 4x the size it needs to be...the rest is foam, and for show.

Okay, totally sorry for the 3 page intro. On with the install!

This is where my catch can is located. It's routed between the 3/8" tube on the valve cover and the 3/8 tube on my "sewer pipe" (thx 2005HHRAUTO!) intake tube.

https://www.chevyhhr.net/gallery/fil.../catchcan1.jpg

These are the 2 PCV ports on the rear of the valve cover. Appropriately named #1 and #2. The PCV valve is located off of port #1.

https://www.chevyhhr.net/gallery/fil.../catchcan2.jpg

Currently (as per ZZP instructions) I have port 1 plugged off. The wastegate wouldn't clear with it in the way. I'm pulling all ventalation from the crankcase out the valve cover from port 2. Also no longer using the pcv valve itself, there's no need.

https://www.chevyhhr.net/gallery/fil.../catchcan3.jpg

Here is the valve cover flipped over. You can see port 1 is inside the valve cover gasket. It flows directly through into the head, then into the oil galley in the block. Port 2 is routed unseen into the baffles above the cams. Port 2 is my only ventalation.

https://www.chevyhhr.net/gallery/fil.../catchcan4.jpg

Here we are following port 1 through the head. It is the 2 slots between cylinders 2 and 3.

https://www.chevyhhr.net/gallery/fil.../catchcan5.jpg

The is where port 1 pulls excess pressure from the crankcase. Located in the oil galley between cylinders 2 and 3.

https://www.chevyhhr.net/gallery/fil.../catchcan6.jpg

And the finished product! The fittings I needed were M20x1/2 NPT Reducer Bushings (online,or PM me) and 1/2 NPTx3/8 90*Barb (Home Depot).

https://www.chevyhhr.net/gallery/fil.../catchcan7.jpg

On a sidenote, I've driven with the can for about 40 miles. 20 of that was limping home...Turned the manual boost contol up a hair (seriously like a HAIR!) I was already pegging the 30psi gauge, just wanted to see if I could quiet the wastegate. Getting on the freeway I got into it a little, instantly blew the coupler from the IC to lower charge pipe. Nothing broke, it actually blew the clamp around the IC! That's ridiculous! I definitely cranked it down, I'll be carrying my 7/16th ratchet wrench around..limped home. I'll fix it when I get up.

A catch can or air/oil separator is especially important on GDI engines since there is no fuel mix going to the back side of the valves; only the oil/air mix from the pcv valve. So no cleaners, additives, top tier gas, etc. would ever have any cleaning effect on that area since it would never reach that area. I recently installed one on our Kia Rio.

PCV VALVES are only on the SS. 2.2 & 2.4 have a straight tube.

Where is all that oil coming from? It should be just vapor.

I thought I read that the PCV valve was needed by the turbo system even with a catch can.

That is not uncommon on turbos and/or impeller type superchargers if your tubes don't have ridges at the ends. Using hairspray on the tube/inside the coupler does helps. Been there done that, have the scars to prove it....

Powell is really on top of this, & maybe you can learn something from his system.
LNF PCV Anti-coking drain back system - Cobalt SS Network

In a way you've made a vac-u-pan set up like you would have on an engine that has a carburetor and headers. Use to have that myself when drag racing.
I can see that would work to a point. But more boost would make more crankcase pressure, which to me would start to over work the oil canister. Running a two port set up would keep the system more in balance.

Those Cobalt guy's can sure carry on with BS talk, lol.

Yes, I agree completely. I assumed both ports vented through the valve cover. I didn't really think anything of it when I removed it. The wastegate needed to be there. It wasn't until I started the how to photos when I noticed port 1 goes right through to the block. So I'll make the 3/8 tube from port 1 fit and get a T over to the catch can. I'm certain this will be the best solution. The can also has a drain line that I will try and tie in with the turbo oil return. That way I don't have to empty it. I'm gonna put some miles on it and I'll keep the thread updated with my info.

Thanks again Cat Man!

This catch can is used on all of the 3516 generators at where I work. You will notice there is a check valve on the drain back to the crankcase. This prevents crankcase pressure going into the canister.
https://www.maesco.com/products/raco...ccv_intro.html
The system works very well. Wish they made one small enough to be used for the SS application.
As a side note the Caterpillar 3516 is a 16 cylinder engine (263 cubic inch per cylinder) using 4 turbo's.

Wouldn't want that! (More pressure in the crankcase) I think there might be barely enough room to squeeze in a -10 T into the turbo return. Which would be great, now I'll need to fit a check in there too. I'll do some research, we have tons of misc air/oil separators at work. Need an M20 check probably to fit.

I'm definitely going to replumb the #1 port. I'm going to have to do some adapting but I'll use PCV valve again. Because I see no real reason to block port 1 at all. Other than wastegate clearance, and to ease ZZP's headaches. They were even kind enough to send the 3/8 plug I stuck in there.

@Dr.Loch - Hairspray! Worked like a charm, got everything settled and pulls to 24lbs. Without the wastegate opening like crazy, now with the 23.6 lb spring it's a monster. I did a ridiculous pull from 2nd to about 75 getting on the freeway (same way I popped it last night) Just amazing, torque steer is my next issue! (Here's looking at you TTR!)

Thank goodness the wife is not fan of the highway! For her it's all 0-40 and traction control keeps her straight.