Open Catch Can system: Anyone have done it?
 

Yeah, It's an other catch can thread.

I'm wondering if anyone installed a catch can in a "open" type installation.

What I mean by "open"? To completely isolate the engine from oil vapor.

The reason why I want that, I'm a car mecanic and I've removed shit load of intake manifold (If your asking, no not a Toyota dealership) and they are always reallllllyy oilly. I really don't want that crap to goes into my engine...

How to plug an open system?

- Remove the PCV, replace it by a freeflow fitting. (The goal of a PCV is to open when vaccum is applied. In a open system, the PCV would stay closed... no need for that!)
- Plug a tube in the freeflow fitting and bring it to your catch can.
- Block the port on the Intake Manifold
- Leave the 2nd port of the catch can open (or you could run a hose far away from the firewall to prevent oil odors).
- Remove the breather tube and block the port on the engine and on the intake tube.(You don't need a breather this way, since now the oil vapor system is positive. The positive pressure of the engine will go out by it's own by the open port on the catch can, most of the oil will be back in the engine pan by the tube and some will be stuck in the catch can)

Older cars where build this way, since emission was not a problem...

This way, no oil vapor at all will be burned.

It's not done on my car yet, but I want to know if someone have done it and IF it have some side effect...

I've heard some statement of this kind of setup... like "idle will be instable" and "your engine will run lean"... I've never done it. On the drawing board, it works...

So, anyone?

In for more info!

I added the basic Cusco can. It goes between the intake and breather. I know others have done fancy setups for their superchargers which involve four hoses and they have caught a LOT of oil. Mine is still empty and shows no oil in the hoses, but I haven't done any SCCA events since installing it.

That is because you aren't hooked to the PCV valve so you are missing the lion's share of the crap you're trying to catch. By comparison the bit you are running your can on is miniscule.

so, a vta can?

did it once, not worth the smell and mess (oily residue over time) in the bay, not doing it again,

Just get a proper air/oil separator (aka a catch can with a filtration system), that way your car doesn't look ghetto with the odd oil drop underneath it

Where do you read that i will drop the oil on the ground? Oil will be drop in the can...

Anyway, I want some info on who have done it... not that I should not do that!

I did this. When I was NA, I had it setup from the PCV valve, then back to the intake. When I installed the supercharger, I had to vent it to atmosphere because the old setup would cause boost leak. You would not believe how much oil it catches.

http://i86.photobucket.com/albums/k8...psa364ab46.jpg

The first time I installed the cusco can, I had it set up wrong, going between the breather and intake. This would not catch anything.

So you put a fitting instead of the pcv valve?

Breather to intake is what the instructions showed, but damn does it look like you're catching a lot more oil with your setup.

What would happen if you just plugged the two intake ports (left hose under the cover and the one on the side of the air intake) and ran the catch can between the breather and PCV with the can venting to atmosphere?

As long as the catch can is able to flow as much if not more out as it is in then you'll be fine. Except the smell and oily residue of course.

If the can causes a restriction and your block is pressurised you MAY not make as much power but you WILL cause oil leaks. Most lip seals like the ones typically used on the rear main or timing cover will flip the sealing lip inside out above 5 - 10psi depending on the design. Below that threshold they will often weep oil. If the lip flips inside out and the spring behind it runs on the crank for any amount of time the oil leak will be the least of your problems.

Hum...

That way, pressure in the crankcase will have no way to escape. Since when the PCV have no vaccum, it's closed. Pressure will be out via the breather tube and will be stuck into the can since it's not vented to atmosphere...

Don't do that!

There really are two different items here. Catch cans and air oil separators. Lots of catch cans out there are just shiny containers with an in and an out. They just hope to catch oil. Separators do what the name says, pull the oil out of the air. Usually with just simple baffles or some type of filter media. I built my own separator with a series of internal baffles like those stacking wooden dolls. Yes mine is VTA so there is nothing pulling it through but the entry ports are offset on the cylinder so it's designed to introduce a swirling motion inside the cylinder. Basic stuff. Since it's made of steel and not clear, sure there is a degree of guesses what's going on inside but I've made them before and never had an oily mess come out the filter. The filter does need to be washed now and then but nothing crazy. I've also done one that had a check valve connected to the exhaust. The exhaust gasses pulled the contents out of the container. That was an experiment and didn't seem to work any better then the VTA.

If you're running a catch can that doesn't have a baffle or filter, you have the potential of oil coming through the outlet port on the can. If it's a separator type, it should technically just be air coming out so you may as well just run it back to the intake tube.

I could be mistaken, just adding my 2 cents

Thanks a lot for your help and comments. The catch that I'll installed will be a Cusco catch can, with no baffle inside. The only thing that left to see is if it will have oil leaking from the open port since it don't have baffle. Personaly I don't think so, since it's only oil vapors that commin' out.

And so you didn't have any engine related problem? Like bad idle? Your car is N/A or boosted?

I've already got a mini air filter to fit at the open output of the Cusco can :)

Woha! Shit loads of oils collected! Did you keep the PCV valve ? Look like the oil is trapped inside the tube!

i run a dual-vented setup, and it works just fine. no oil in my pipes, which is the whole point. there are theoretical drawbacks, particularly not creating vacuum in the crankcase at idle, but that's theoretical. in reality, it's just a damn catch can, and if there's no oil in your pipes, it works.

My BRZ is still in the works but it shouldn't be any different they the other systems I've built. If you hook it up correctly there should be no side effects. Also don't use huge hose, mine now uses 1/2" stainless hard lines. My car has a turbo but its shouldn't really matter, any engine with DI is going to be very touchy about oily pistons and I think as time goes on we will see issues around this.

http://i139.photobucket.com/albums/q...ps7678e85c.jpg

These lines connect to the port under the AC compressor and the one under the back of the manifold. Those they connect to the inlets on the can. I will cap off the unused port left on the manifold and my intake piping does not have anything for that side so I don't need to worry.

Here is a shot from when I was making the can, these baffles now have a series of decreasing sized holes in each layer.

http://i139.photobucket.com/albums/q...ps03dff63a.jpg

The concept is the oil clings to the walls and gravity pulls it to the bottom where is then goes into a hose that runs down the side of the tranny. The hose acts as the storage capacity and a handy drain. The air is left to vent out the top and that "exit" is only accessible from the inner most chamber, the cleanest. I like to use baffles instead of filter media because then the can needs to be able to open for cleaning. This design is solid state one hunk design. I'll drain it every so often and run solvent through.

Yes I kept the pcv valve. Yup the hose traps the oil. If you look closely, the oil residue comes out on the other side which is vented to atmosphere. That's the downside of the unbaffled cusco can.

When I installed it between the breather, it caught almost nothing. After I hooked it up directly to the pcv valve, that's when all the junk got caught.

I don't understand why this would be needed, UNLESS there is FI involved. Does it really make that much of a difference to have any type of catch can or AOS when NA?

Oily pistons are not good, FI is just more prone to detonation so it needs that larger window. NA can still benefit but sure not as much

I just prefer to keep my pistons clean even if I run N/A !

Did you connect your catch can like this?

http://www.ft86club.com/forums/showthread.php?t=21079

I connected it as the cusco manual shows and catch nothing.

lol.

Thank you!

Well I do for the breather parts...

For the rest, I've plugged the PCV valve, the manifold nipple (From the PCV) and completely removed the OEM tube PCV to manifold.

That way, all the vapor will go out by it self on the breather side and goes into the catch can

But you got to leave one port of the catch can open like they said on the Cusco manual.

I will repost later on for the results of this since my car is still in winter storage.

when you say you plugged the PCV, what do you mean?


I have both my Radium catch cans vented to atmosphere, no recirculation back into the intake, im having a vacuum leak at idle, would this cause it?

Damn that's an old post from 2014 @Kris86 !

I've put a plug on the PCV, but I would not be forced to do that since a PCV only open with vacuum.

I don't think this is your issue ! Recheck if your plug for the intake port is okay, and check the brake booster vacuum hose too !

I know :sigh:

Sorry about that, but trying my best to figure out what wrong with my car :mad0259: