AVO Breather Tank for Turbo

[ChrisD]

Originally Posted by go_a_way1

honestly I dont think mine is catching anything either, but my car is still NA so I am not worried about it. The inside of the box is a diamond pattern grill mesh material but I think the mesh is way to big to really catch much of anything.

Yeah the problem is mine is a built engine with bigger ring gaps and stage 4 AVO turbo on it now, so this becomes more of an issue. I looked inside the catch can the other day as well and saw the mesh you are talking about - I kind of assumed it is meant to catch the oil by the oil vapours kind of condensing on the mesh, rather than oil actually physically getting caught by it (as like you say the gaps are too big for that).

But yeah considering the hose going to the catch can is bone dry and the hose going to the inlet manifold is soaked in oil, I'm assuming none of it is ever even getting to the catch can. Our plan at the moment is to just block off the hose that goes to the top of the inlet manifold, so that it has to go to the catch can. Also might have the catch can vent to atmosphere rather than recirc back into the intake

[go_a_way1]

Originally Posted by ChrisD

Yeah the problem is mine is a built engine with bigger ring gaps and stage 4 AVO turbo on it now, so this becomes more of an issue. I looked inside the catch can the other day as well and saw the mesh you are talking about - I kind of assumed it is meant to catch the oil by the oil vapours kind of condensing on the mesh, rather than oil actually physically getting caught by it (as like you say the gaps are too big for that).

But yeah considering the hose going to the catch can is bone dry and the hose going to the inlet manifold is soaked in oil, I'm assuming none of it is ever even getting to the catch can. Our plan at the moment is to just block off the hose that goes to the top of the inlet manifold, so that it has to go to the catch can. Also might have the catch can vent to atmosphere rather than recirc back into the intake

You are right on it supposed to be letting the vapors condense on it, but I feel there is not nearly enough mesh to be even slightly effect for that concerning how much flow goes through there. I might convert mine to vent to atmosphere thats not a bad idea!

[ChrisD]

Originally Posted by go_a_way1

You are right on it supposed to be letting the vapors condense on it, but I feel there is not nearly enough mesh to be even slightly effect for that concerning how much flow goes through there.

There is no flow going through mine, that's the problem haha

[go_a_way1]

Originally Posted by ChrisD

There is no flow going through mine, that's the problem haha

fail hahaha!

[Skorov]

Originally Posted by ChrisD

What is different about other catch can systems that makes them better?

I'm not an expert so I'm not going pretend to know much about how catch cans work.

But what has been explained to me is that the AVO one is nothing more than a metal can. Whereas, say Radium, actually has some technology in their cans to better funnel and actually catch the oil.

[ChrisD]

Originally Posted by Skorov

I'm not an expert so I'm not going pretend to know much about how catch cans work.

But what has been explained to me is that the AVO one is nothing more than a metal can. Whereas, say Radium, actually has some technology in their cans to better funnel and actually catch the oil.

Well the Avo one has a few separate layers of metal mesh inside it. The radium one is an empty metal can but has a filter mesh at the top as far as I can see.

[Northwest86]

They do the same thing. Basically they cool and therefore condense the vapors in the air flowing through them. The mesh adds some surface area to help the cooling essentially. As long as it flows over the mesh it'll work. The radium works bloody well though. I've drained a pretty solid amount of nasty oil out of them. Catch cans are pretty simple things and you can spend as much or as little as you want. Hell a $20 ebay job does much the same job. They just may not look and fit as nice.

[ChrisD]

Originally Posted by Northwest86

They do the same thing. Basically they cool and therefore condense the vapors in the air flowing through them. The mesh adds some surface area to help the cooling essentially. As long as it flows over the mesh it'll work. The radium works bloody well though. I've drained a pretty solid amount of nasty oil out of them. Catch cans are pretty simple things and you can spend as much or as little as you want. Hell a $20 ebay job does much the same job. They just may not look and fit as nice.

Yeah that's my understanding. The problem with the AVO one doesn't seem to be the can itself, but the way they want it to be plumbed in. I still don't get what on earth is meant to make any of the gas/oil go to the catch can and not just go straight back into the top of the inlet manifold, as the catch can doesn't sit in line between the PCV and inlet manifold like in most other catch can setups. That line between PCV and inlet manifold is still there but then also breaks off to the catch can as well, and it seems like none of it ever actually ends up going to the catch can...

[Northwest86]

Ok so talking basics. When you are off boost, the intake manifold is in vacuum and the catch can is Neutral basically. So the vacuum pulls the PCV open and vapor is pulled right into the intake. That'd be why it does nothing.

Your pictures are a maze for me really haha. It almost seems like you are trying to combine one catch can to do two jobs. The PCV one needs to be able to be pressurised and be inline. The Crankcase works on a completely opposite system and if you mix them, then you just pressurise your crankcase basically.

For the crankcase side you want to take the hose from the Crankcase hose that originally connected onto your intake just before the throttle body. It's the molded one. That will get routed through the top of your catch can and the the outlet will route to before the turbo aka the airbox. So basically where the PCV sees Intake Boost when under load, the crankcase would see a vacuum from the turbo sucking air in which pulls the crankcase vapours towards your turbo/throttle body.

You need two different systems. I've found that personally my PCV valve system pulls a fairly minor amount of oil out. So recently I would of done 5000kms with a few track days. My PCV valve catch can pulled maybe a couple of tablespoons of oil if that. Whereas the crankcase catch can pulled a solid 3/4-1 cup of oil. Hopefully this info helps. This is how the system should be routed and what happens in each of the hoses. Hopefully you can route them in your system to suit. You may need the second catch can though. One cannot do both systems unless is has separate chambers.

[ChrisD]

When you are off boost, the intake manifold is in vacuum and the catch can is Neutral basically. So the vacuum pulls the PCV open and vapor is pulled right into the intake. That'd be why it does nothing

Thanks that's exactly what I thought, but I figured I must be missing something as why would AVO sell a kit like this that blatantly isn't ever going to work. Plus I thought that Fensport had their car setup in the exact same way as mine and hadn't encountered this problem, but turns out theirs isn't the same.

For now we're just going to block off the port on the inlet manifold and turbo intake pipe so that it forces everything to go through the catch can, and have the catch can vent to atmosphere. Will see how that works out

[Northwest86]

You'll still need a second system to make it all work properly. With the turbo intake pipe and the inlet manifold pipe blocked you lose both the vacuum and pressurised lines when under load. So basically you now have a Crankcase with atmospheric or perhaps slightly pressurised and a PCV that'll never open because it'll never see the vacuum it needs to open. At which point you may as well just block off every hose and just remove the catch can. In a NA car you can use the one can for both I believe since both systems see Vacuum at the same time (when off throttle) and both see atmospheric or close to it when under load as they are both connected into the intake essentially. The third fitting it appears is simply for an overflow line to go back to the oil filler or to connect some weird vent system. Get a second Can of any description and simply route as they should be. Ignore whatever crazy stuff the instructions say.

[xwd]

I'll re-iterate what Northwest86 said, you don't want to tie them into the same can while turbo. There is a reason why the Radium FI system uses two separate cans.

If you want to use one can just eliminate the intake manifold connection since it doesn't do as much.

[Northwest86]

Yep. Also if you block off those two hoses, it'll turn into a game of what blows first. A hose off the breather tank or a main seal from the crank. In a turbo application they need to be treated as two separate systems.

[ChrisD]

Originally Posted by Northwest86

So basically you now have a Crankcase with atmospheric or perhaps slightly pressurised and a PCV that'll never open because it'll never see the vacuum it needs to open.

But there won't be any PCV valve to open now. That was never in line with the catch can anyway - that valve sat between the port on the engine and the inlet manifold (not between the port on the engine and the catch can). So now we will literally just have a hose going straight from the PCV port on the engine case into the catch can. Then the breather hose from the other port on the engine case will go into the catch can as well. Then the catch can will go to atmosphere. That should work right? My engine builder seems to think so