john ward

iTrader: (7)

i figured the point of post was someone running a standalone with no emissions needing a can but you can do either way

KhanArtisT

iTrader: (2)

The crankcase pressure that fills up my catch can at least half way with the nasty oil and water mixture in less than 5,000 miles.

The setup you suggested is a catch can too. The random container thing works but looks ghetto. I'm all for function over form but I'll spend $20 on an ebay catch can for the sake of not having to keep a stack of empty coke bottles in my garage And believe it or not a lot of people actually get the catch can for appearance purposes.

Aaron Cake

iTrader: (1)

The stock purge valve is vacuum controlled so that it only bypasses under high vacuum. The top port opens the two bottom ports and allows flow through them. One port has a small orifice which is calibrated to control flow so that engine operation isn't effected from excess air when the valve opens.

When using a catch can, I just replace the valve with a generic PCV valve from the parts store.

Running vacuum through the catch can keeps the stock crankcase venting function in place. Air flows from the nipple in the center iron to the center of the engine around the eccentric, capturing all the junk the builds up on the way as it flows back up the oil filler neck, out through that nipple and into the intake to be burned. Just plumbing both nipples to a catch can without this circulation allows all that nasty to build up. The evidence of this is the white junk that accumulates under the oil cap and the rust formed in the oil filler neck.

The point of a catch can is to prevent excessive oil from entering the intake. As would be experienced in an engine running high boost or one under fairly high G-forces. Or engines built a little loose or worn out. There is no reason not to both incorporate the function of the catch can and the PCV function needed to keep the crankcase clean.

Crankcase pressure will build up from natural gas bypass from side seal clearance or boost pressure. Excessive fuel will exacerbate the problem as the oil film is washed from the irons.

TitaniumTT

Aaron, can you please comment on the routing in the pic provided.

I've been toying around with this for quite some time as I do need a catch tank of sorts but don't want to burn all the contaminents off. I'd rather capture them to be emptied. My idea consists of basically a double chamber tank. The first chamber if you will is fitted with a breather filter and is plumbed to the nipple on the center iron.
The nipple on the oil filter neck would be plumbed to the bottom of the second chamber. This chamber would be filled with a steel wool material and have a drain as well. This chamber would have a smaller sintered type filter on it. The second chamber is routed to the TID.
The theory is the vac created will circulate air through the crankcase but the steel wool will capture any crap in the second chamber and not allow it enter the intake.

Aaron Cake

iTrader: (1)

Since the contaminates are in vapour form, I don't know how well that would work. They would probably pass straight through the steel wool filter. What's wrong with burning the stuff off?

TitaniumTT

The crap that's getting caught in my can right now isn't in vapor form, I believe that I also have oil sloshing up the oil filler on hard turns Regardless of how hard I push the car in a straight line, there seems to be minimal buildup in the can, as soon as I hit the backrds or the track, it's virtually overflowing. I also have other problems with such a cold running engine and the moisture that's in there so I need to address this.

There's nothing really wrong with burning the vapor as long as it's consistent. What I don't want to see happen is the intercooler become saturated with oil. Given the rate that I can fill the catch tank, it'll soak the intercooler rather quickly. Something that I'd like to avoid which is the reason for the double chamber and something to slow it down and catch it.

87FCTurboII

iTrader: (2)

So when the upper nipple on the filler neck is connected to a vac source via a PCV valve, and the catch can is connected to the nipple on the center iron, no oil would be vented to the catch can while the car is running, correct? It would be sucked into the engine and burned? So I'm assuming the catch can would only collect excess oil once the car is shut off?

Also, wouldn't this setup act as a vacuum leak at idle? Even if air is drawn from the TID, it is still bypassing the throttle body, which seems like it would cause a high idle.

Rob XX 7

iTrader: (8)

I just have the hose going to the filler neck, yes I think it can be better going to the center iron or even have heard that the proper way is to run 2 cans, but I aint running NASCAR with this thing.

in the last image I had not yet powdercoated it

Arnomardi

iTrader: (6)

So i just got mine installed and one hose it went from the center iron to the catch can and the other nipple on the catch can is left open as a breather.

zombiemaniac

seventhgear

I have toyed with the catch can or no catch can theory for so long now. 🤦🏻‍♂️ i think im ready to finally install, but still not sure which way i want2 do it.

cpt_gloval

iTrader: (1)

Sup.

Guy from the future here just to say it's always fun to land on these threads while actually doing a search and immediately see "why don't you do a search" lol

Aaron Cake

iTrader: (1)

It's also quite amusing when a thread lays out with exactly how something should be set up, complete with explanations why, and then there are a bunch of posts after that just saying "I stuck a hose on it and let it drip all over".