oil breathers

ttocs

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In another post recently adder said that breathers can be used if the pcv system is modified correctly. I didn't want to crap up that post so I started this one as I have a breather and just wondered if the correct modifications had been done.

What needs to be done?
 

rz5.0

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Your need to have a pcv system that is isolated from the rest of the intake system. If you put a breather everything pcv related has to now be set to be on its own. Cap the intake side of it put a breather on each valve cover abd you also have to vent the pcv in thr back of the intake.
 

rz5.0

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If you have a breather On a pcv system still hooked up to the intake. You are caising prpblems cus you are venting metered air. Causing all the calculations your cars computer to be off.
 
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ttocs

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Can you post a pic or a diagram of what it is all supposed to look like? I am looking now but can't find anything.
 
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I found a diagram showing it all but an actual pic of where the hose hooks up too would be helpful. I can't remember where mine is going too, going to check today....
 

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This may be a little different since you don't have a 4.6, but here's what I was told when I looked into it:

OP, that will create an unmetered air leak. Either keep the PCV system as a CCV, or install breathers on both valvecovers and run the PCV system as a OCV. Doing so will require that you plug both the fresh metered air inlet on the intake tube and the vacuum port on the plenum.
The problem with just installing a breather on the driverside valvecover and not addressing the other side of the system is that you'll have an unmetered air leak, as stated above. Unmetered air will be able to enter the crankcase via the breather filter and drawn into the plenum via the PCV valve. This unmetered air is unaccounted for in regards to fueling...not a good thing.

Either vent both valvecovers to atmosphere (OCV) or keep the system closed (CCV).

On the 4.6 you insert breathers on both valve covers and plug the hole on the plenum as well as the one on the intake.
Should be fairly similar on a 5.0 IO believe.

http://i46.tinypic.com/2wlwxec.png
 

rz5.0

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There should be a line that goes from the valve cover filler neck to the intake (power pipe in your case).. Then on the back the pcv valve hooks up to the intake. Usually on the back or under. Depending on intake..
 

Addermk2

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The short and sweet version is...

If you put a breather on your valve cover(s) and are still running your factory pcv valve in the rear of the intake, you are allowing unmetered air to enter your intake.

If you wish to run a breather in your valve cover(s), you need to remove the pcv valve from the rear of your intake manifold, block off the hole, and cap both nipples on the manifold that source vac to the pcv valve, and eliminate the hose running from your intake tube. The home in the intake tube (or elbow near the TB) must be capped.
 

rz5.0

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The short and sweet version is...

If you put a breather on your valve cover(s) and are still running your factory pcv valve in the rear of the intake, you are allowing unmetered air to enter your intake.

If you wish to run a breather in your valve cover(s), you need to remove the pcv valve from the rear of your intake manifold, block off the hole, and cap both nipples on the manifold that source vac to the pcv valve, and eliminate the hose running from your intake tube. The home in the intake tube (or elbow near the TB) must be capped.

I would not cap the pcv hole on the lower intake.
It should be ran to a catch can with a breather also.
 
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