PCV Valve / Rocker Cover Breather

[munday]

No it won't, but I doubt any setup will without some sort of vacumm like an electronic pump or exhaust valve?

But it will help...

If it vented to atmosphere then there is no way the inlet charge can be contaminated. The breather...well it doesn't matter if its under vacuum or pressure really, as long as the blowby gasses have somwhere to go

 

[FeNder]

So does this mean i can remove my dead pcv valve , put a tube in its place , and run a line from that to the catch can , then from the catch can to the inlet mani , is that alright not having the one way pressure thing ?
or will it still have it due to the inlet negativity ?

 

[Gee]

If it vented to atmosphere then there is no way the inlet charge can be contaminated. The breather...well it doesn't matter if its under vacuum or pressure really, as long as the blowby gasses have somwhere to go

Does a PVC valve also let fresh air in to the engine..?

 

[Aidan@EP-styling]

Does a PVC valve also let fresh air in to the engine..?

sorry i havent read much of this thread yet but Gee do you mean does it let boost into the engine from the inlet manifold? answer to that is no cause that would result in the engine been pressurised which is not good.

^^^ ignore if that is not the answer your question is looking for

 

[Gee]

No, not boost.

But fresh air.

I read it is there to release gases from the engine, but also to take in fresh air?

 

[munday]

Does a PVC valve also let fresh air in to the engine..?

I dont know much about PCV valves, but i really dont see the point in having fresh air in there, it will do nothing to help anything! lol

If it were letting fresh air in, it could only be under boost pressure because thats the only time there would be higher pressure in the inlet to the rocker cover. :drive:

 

[Aidan@EP-styling]

PCV valve is a one-way vlave. It lets gasses out thats all

 

[MWP]

I dont know much about PCV valves, but i really dont see the point in having fresh air in there, it will do nothing to help anything!

Blowby gasses contaminate engine oil (and do other nasty things like create corrosion).
The PCV system removes the blowby gasses and replaces it with fresh-air.

BTW, hi Gee

 

[Gee]

Hi MWP

OK, so the PCV removes gases which is replaced by fresh air.

So, there is no sort of pump/vacuum affect, the fumes are just simply replaced by fresh air once, removed.....

I think

 

[Rory]

the catch can catches the contamination tho

But there is still the chance of the inlet being contaminated.

I know my line being run under the car has the oil vapour in it, as its the same colour as the lines.
Not as dark, but there is colour there. ( The line was clear when i put it on)

@ Gee - As stated above, i know my setup works for vacume(See above)

As far as im aware, the PCV only works one way.
When the car is under load (Boost), there is a vacume effect in the inlet manifold, that opens the PCV to let the breather system work.

When not in boost, the PCV closes.

As for fresh air, its a sealed system, so it cant possibly let fresh air in.

This is my reckoning on how it work, but not 100% sure.

 

[Aidan@EP-styling]

As far as im aware, the PCV only works one way.
When the car is under load (Boost), there is a vacume effect in the inlet manifold, that opens the PCV to let the breather system work.

When not in boost, the PCV closes.

I dont think that is correct. When on boost then boost will be coming out from the inlet manifold? there wont be vacuum. When you go off-boost and then everything goes to vacuum then this opens the pcv valve and releases the blow by gasses. - Thats the way I always understood it as how it works

 

[Rory]

I dont think that is correct. When on boost then boost will be coming out from the inlet manifold? there wont be vacuum. When you go off-boost and then everything goes to vacuum then this opens the pcv valve and releases the blow by gasses. - Thats the way I always understood it as how it works

I think you may be right.
My head is up my Ar5e......

 

[dan_ep82]

But there is still the chance of the inlet being contaminated.

i know but cant be that bad if the standard setup runs this way without a catch can at all

 

[Gee]

Yeah, most of it will be removed some may get through..no big deal.

Oil is changed every 3,000 miles anyway and the setup I am going for will work better than what I have now.

 

[Rory]

i know but cant be that bad if the standard setup runs this way without a catch can at all

Agree its fine on a standard setup.

But when you run bigger power and torque, there is more chance of ruining the motor, especially if its well out there.
Id rather haver the cleanest charge possible, makes for a healthy engine.

Im not starting an arguement, far from it, just mearly asking why have the possibility.

Gee - All of a sudden you have went from not knowing what to do, to knowing what to do?

Anyway, it doesnt matter if the oil is changed every 3k miles. Its not the oil that gets contaminated, its the inlet charge of airflow, weather N/A or boosted.

 

[Gee]

If the blowby gases don't get released from the engine, then it is the oil that gets contaminated?

Thought that was the whole point of the PCV?

Gee - All of a sudden you have went from not knowing what to do, to knowing what to do?

Well this thread is 5 pages long and the one on Austarlet Club is about 4 and both contain lots of good info so..

 

[weeJohn]

What a fu'king engine bay!!!!!

It seems Rorys set up seems to work as well as others listed here, when I thought it would not. I have learned something new and thats good, thanks Rory.

That proves to me that there is more than 1 way to do this efficently, and the efficient ways are the correct ways imo.

Guess that means there is also wrong ways, but I will let someone else say what ways they are lol.

Gee if you are worried about having a filter on the top of your rocker cover that will spread oil on the cover, put the filter on the end of a piece of hose, away from the cover mate.

 

[Gee]

Just to let you know that I get droplets/liquids in the can, as some also escapes from the breather on top and drops over the ouside of the can.

WeeJohn,

I am going to plumb from the breather to my hose on the turbo inlet.

 

[munday]

Just to let you know that I get droplets/liquids in the can, as some also escapes from the breather on top and drops over the ouside of the can.
QUOTE]

Goes to show that the catch can is not 100% efficient at getting all the oil out...best to vent to atmo

 

[Gee]

Just to let you know that I get droplets/liquids in the can, as some also escapes from the breather on top and drops over the ouside of the can.
QUOTE]

Goes to show that the catch can is not 100% efficient at getting all the oil out...best to vent to atmo

We know it is not 100% efficent, but my can is not baffled either which will help.

And if the droplets are coming from the breather, its still the atmosphere.