PCV Valve / Rocker Cover Breather

weeJohn

weeJohn

Lifer
Gee it would be a real shame to butcher your hose set up, that would not have been cheap and it looks good.

If it was me, I would remove the rubber hose from the left hand elbow and fit the filter of the catch can on there. The pvc valve could be readded to the other hose before the catch can, but I think a new can would be needed, one with 2 outlets only. Then the other spout on the can could be connected to the inlet mani.

I got it a while ago but my can only cost about £70 to my door, off e bay motors from Japan.
 
Gee

Gee

Member +
Hmm..maybe.

The rocker does need a bit more weld on it thou..seems like it is leaking.
 
Gee

Gee

Member +
Rory said:
I have the PVC gutted, and running into the same line from the cam cover breather.
In turn, that line runs into the catch can.
The other port on the can i run a line from it, under the car and facing away from the airflow.
This in turn acts as a vacume, to pull the gasses out and leaves the oil residue in the can.

Simple yet effective.
See below,

DSC_0434.jpg
Click to expand...

Don't see the difference between mine and yours?

And this sexy engine bay has the same setup.

Starbo346.jpg
 
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davehart

davehart

Member +
munday said:
Not referring to any setup in particular :)

Edited my post to make it more clear, you are right i meant venting to atmo is illegal
Click to expand...

So catch cans with a breather filter or just a breather filter on the rocker cover are illigal then?
 
Rory

Rory

Lifer
weeJohn said:
Rory judging by the colour of your hoses to the can, you dont get much residue in your can, or do you?
Click to expand...

Hey John,

Beleive it or not, but i do get residue in the tank. Mushy, stinking stuff! :p
Also condensation which is innevitable.

Gee - No diffirence in function between them.
Only diffirence being, i run a line to the underside of the car away from the airflow, to act as a vacume. That setup is venting in the engine bay through the little filter. Id rather not have this, hence i run the line under the car.
 
Gee

Gee

Member +
Your site says that the function of the catch tank it to prove an expansion and cooling space for the blow by before pasing it back on to the intake. But the picture you have highlighted, the other side of the tank vents to the atmosphere?
 
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munday

munday

Member +
davehart said:
So catch cans with a breather filter or just a breather filter on the rocker cover are illigal then?
Click to expand...

I believe so yes, that's my understanding anyway

WeeJohn - I see what you mean about the turbulence in the rocker cover, but surely the only thing causing an overall change in volume is the blowby past the rings, whenever one piston is moving up another is moving down to keep the overall volume the same. I suppose the differing speeds the pistons are moving in relation to each other could have an effect
 
Gee

Gee

Member +
Rory

Rory

Lifer
Gee the PCV valves are spring loaded.

The only diffirence between the way i have it and Hardcore (Rory) is he has it the line tapped back into th intake for the vacume.
I run mine away from the airflow under the car for mine.
Works the same way, but im garanteed not to get and contaminents in the intake.

Thats the only diffirence.
 
GT-TD04

GT-TD04

Supermoderator
weeJohn said:
Thats the whole point of a catch can mate, when the vented gasses pass through the catch can the vapours are "dropped" in the can to prevent them going into the inlet.

Not 100% efficient, some vapours will still get through, but the majority wont.

Gee in my opinion your set up is wrong. There is nothing in your set up that will remove the vapours from the crankcase into the can. Have you ever had to empty it?

This is my setup, please dont think this is a way of showing how yours is wrong as its different from mine, this is the way I do it.

DSC00246.jpg


I use 2 pvc valves so as the valve nearest the inlet mani closes under boost, preventing the can getting pressurised. The valve in its normal place stops anything in the can being sucked back into the crankcase. The breather filter does as it named, its on the other pipe off the rocker, where the standard dump valve hose was connected.

I get an emulsified oil in my catch can, like a melted bar of fudge.

I empty it about every 6 months, the ammount in it varies.
Click to expand...
Im fitting mine now in a few miutes,will the above picture be a safe way to do it?

Just to make sure:)
 
Gee

Gee

Member +
Well, yeah.

But I know others running the same setup as me, one guy has 600WHP and uses the same setup, race cars use the same setup.

But others are saying it causes oil contamination, but this is not an issue on race cars as they change the oil out every race.
 
davehart

davehart

Member +
munday said:
I believe so yes, that's my understanding anyway

WeeJohn - I see what you mean about the turbulence in the rocker cover, but surely the only thing causing an overall change in volume is the blowby past the rings, whenever one piston is moving up another is moving down to keep the overall volume the same. I suppose the differing speeds the pistons are moving in relation to each other could have an effect
Click to expand...

From my reading of the law doing this to the PCV Valve is against the law but not to the Rocker system.

Allthough from reading on a few sources it is not good to put a breather on the Rocker cover but if the PCV system is in place it should not do any damage to the engine.
 
Rory

Rory

Lifer
Gee said:
But others are saying it causes oil contamination, but this is not an issue on race cars as they change the oil out every race.
Click to expand...

Im a bit lost with that comment?
How can it contaminate the oil?
The only thing its contaminating is the intake charge, if your running the vacume into the inlet (which your not). Your still running the PCV in place, which should help.

Your setup will work.
On a personal note, id rather not have any contaminents going into the inlet cahrge.
 
Gee

Gee

Member +
it completely removes the function of the PCV system which is there to remove dirty crankcase gasses.
Without those crankcase/blowby gasses removed, oil will become contaminated at a much faster rate which causes other problems.
Click to expand...

Not read the links I posted yet, but as you can tell I'm not sure with this stuff anyway, so just throwing quotes in there from other sources.
 
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Rory

Rory

Lifer
That is basiclly saying that, if you run the breather onto the intake, without the PCV than it will contaminate it.

You will be fine, as you have the PCV in place.
Mine will be fine as it doent breathe into the intake.
 
Gee

Gee

Member +
What PCV mate..look at the picture.

Its been removed and 2 U/N fittings welded in place.

I guess thats the difference between ours.
 
Rory

Rory

Lifer
Sorry Gee, looked at the wrong picture (or a picture of your old seup)

Only diffirence between ours is, that i run a line to the underside of the car away from the airflow for the vacume.
You run a filter on the top of your can.

Thats the only diffirence.
 
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