Oil Catch Can

[turbotrana]

If you can show me an easy way to get pics down to 33kb I will. I can get them just under 100kb and could post pictures previously but 33kb just does my head in. I don't want to use that imdur thingo if can avoid it.

I have pics of how I weld up the catch cans also. I use a system where the oil drains back into the engine on shut down via one way valves and gravity.

Edited 03/05/15 02:50 PM by turbotrana

[OZYWALKER]

Don't upload the pics to the forum use photobucket or imageshack etc then use the image code to post them up. Or upload the pic through the tapatalk app and it will automatically upload them to imageshack.

[norrs]

Install tapatalk on your mobile then just take the photo while in the middle of your post and upload no worries. I don't seem to have a limit on the size. I think tapatalk hosts it or something.

Anyway what old mate says seems to make more sense from what I now understand of how the system is supposed to work. It sounds like the Pcv inlet needs fresh air like one venting to atmo on top, while the outlet Pcv sounds like it should be a non vented can so it still can generate vacuum from the intake manifold. So two cans

I found this nice explanation on a US forum:

quote-----------------

Your pcv system is designed to use the pressure differance between the atmosphere and your intake manifold to vent your crankcase. The pcv outlet into the intake manifold is low pressure (vacuum), and the pcv inlet in the air box is high pressure (atmospheric pressure). The difference in pressure forces air to flow in through the inlet (air box) and into your crankcase, the blow by gases are sucked out of the crankcase through the outlet (intake manifold).

Even with the stock setup, the pcv system will not function well under hard acceleration. This is for two reasons, the first is that more blow by gases will be generated as you accelerate. The second is, that when you fully open the throttle, you tend to loose the vacuum in the intake manifold. But because of the air filter restriction, there will still be some flow in your pcv system, but sometimes not enough.

Now look what the air intakes you have described have done to make a bad situation even worse. In order to be compliant with pollution regulations, they have moved the pcv inlet from the airbox (whch they don't have), to the intake tube. Now when you accelerate hard and fully open the throttle, the pressure will equalize between the intake manifold and the intake tube, until you have enough rpms that the throttle body becomes a significant air restriction. So for most of the time with these intakes under hard acceleration, there is no pressure differential between the pcv inlet (intake tube) and the pcv outlet (intake manifold), and hence no air flow in your pcv system. So the blow by gases build up in your crankcase and have to vent out. The blow by gases will find the path of least resistance, which will more than likley be back out the pcv inlet.

When you don't have an airbox with your intake, the solution of replacing the stock pcv inlet with a filter on the valve cover works. This still maintains the air pressure differance between the pcv outlet (intake manifold) and the pcv inlet (the filter to the atmosphere). So your pcv system will continue to work like the stock system. The only catch is that you will no longer be compliant with pollution regulations. For pollution reasons, the inlet is supposed to placed so that any blow by gases that do backflow out of it, are sucked back into to the intake to be consumed by the engine (hence the placement in the airbox).

The reason for the filter on the pcv inlet, is to filter out dust and other large particles, so they don't get sucked into your engine.

[turbotrana]

http://s1068.photobucket.com/user/Tony_Goodlich/library/Mobile%20Uploads?sort=3&page=1

I could not take a photo of the vacuum side in situ as it is bolted under the intake manifold.

Basically you have three chambers in the canister. The middle chamber is filled with scourers. The bottom side fitting of the cannister goes to the PCV valve. There is a fitting on the top middle of the cannister that goes to the inlet manifold.

There is also a fitting on the bottom of the cannister that goes to the sump but it has a one way valve and allows oil to drain back into the engine on shut down but closes when there is vacuum.

Then on the overflow side (under load) you have that long cannister next to the rocker cover. Its about 25mm diameter and connects to the back of the rocker cover. The cannister is baffled inside and connected to the intake of the turbo. It allows oil to drain under gravity to the back of the rocker.

Its hard to get your head around but it works.

Edited 04/05/15 02:36 AM by turbotrana

[CHLAXN]

Here is mine limited for space so this will have to do.

[GUN-808]

Hi guys ..

Im just about to build a small setup for a bit of breathability ..

Im, for now ,just goin to run it to atmo with a small ProFlow catch can (may plumb the filter back to intake or airbox at some stage )

Im using the -8 ProFlow fittings into the rocker cover and then running both of them into the can with -8(1/2") lines..

Main Question is .. What do I do with the rear line with the pcv elbow in it ?? The hard line ?? Just stick a bolt in it and block it off ?? Or what ??

I will also be blocking off the small hole that goes into the crossover..

Will this all work or will it cause issues like some have said ? Going off others' pix they seem to have this system without problems..

[bjc]

The rear breather can cause an idle issue but it normally isn't to severe with which blocking it should work. With it breathing to atmosphere there can be a build up of oily smoke (fumes) under the bonnet with no vacuum being placed on the the engine to suck the fumes out.

TBH I'm not sure if it's a big issue or not but keep an eye on it just for reference.

[GUN-808]

ok thanx mate..

I have a slight change of plan..

going off your advice I dont want the smell at all so im gunna plumb back the top breather port (where the little filter goes on top) into the X-over where the front breather goes now.. also going to add a 1 way valve into the the pcv line going to the catch can to copy the stock valves function..

hopefully iv got it sorted properly..

[qwert]

I'm just about to do one as well.

Had mine for 6 months.

I'll put a pipe that goes down just before the bottom of the can from the inlet.

Then put scourers up the top just like ol mate did.

The pipe lets the oil channel to the bottom of the can.

[daveyboii]

just wondering if anyone found a simplistic way on what to do with these when you're running a oil/air separator from PCV to plenum and big boost (I have -8an hose cause I overread a few saying you need to use bigger hoses) bvut now questioning how theyre going to stay on under pressure and most of all what to use to adapt these to -8an diameter 

 

thanks.