PCV valve?

[Dino Dino Bambino]

Dino Dino Bambino was referring to his "06" GT 3v which has the pcv valve on the driver's side, opposite of the Coyote pcv valve which is on the passenger side. I would also assume that when at zero vacuum, gases get pushed into the intake from crankcase pressure thru the driver's side much in the same they get pushed into the intake from the opposite side on the 3v cars.

Thanks for the correction. I mistakenly thought that the PCV valve was on the driver's side valve cover on the Coyote. However the principle of how the crankcase ventilation system works is basically the same as it is on the 3V except that the valve covers are reversed. Therefore you'd want your Coyote catch can on the passenger side whereas on the 3V, you'd have it on the driver's side.
I have one on both sides but the passenger side remains bone dry as it's the supply side to the CCV system. The only situation where you'd collect oil in both catch cans is if you have excessive blowby of combustion gases past the piston rings. This can happen in forced induction applications, even in the absence of ring/bore wear, simply because some of the elevated cylinder pressure "leaks" past the rings. That's why those applications really require catch cans on both sides, but with a one-way valve to prevent pressurised gases inside the intake manifold from entering the crankcase.

 

[06 T-RED S/C GT]

Thanks for the correction. I mistakenly thought that the PCV valve was on the driver's side valve cover on the Coyote. However the principle of how the crankcase ventilation system works is basically the same as it is on the 3V except that the valve covers are reversed. Therefore you'd want your Coyote catch can on the passenger side whereas on the 3V, you'd have it on the driver's side.
I have one on both sides but the passenger side remains bone dry as it's the supply side to the CCV system. The only situation where you'd collect oil in both catch cans is if you have excessive blowby of combustion gases past the piston rings. This can happen in forced induction applications, even in the absence of ring/bore wear, simply because some of the elevated cylinder pressure "leaks" past the rings. That's why those applications really require catch cans on both sides, but with a one-way valve to prevent pressurised gases inside the intake manifold from entering the crankcase.

So far at this point, It hasn't been necessary to add a second catch can on the passenger side, thanks to adding an inline one-way check valve between the intake manifold and catch can on the driver's side. The reason for adding the inline one-way check valve, was to prevent excessive blow-by of combustion gases from getting inside of the intake manifold due from the elevated cylinder pressure of the Saleen VI blower which causes the blow-by gasses to leak past the piston rings. If in the event, pressurized gasses end up getting pushed inside the intake manifold thru the passenger side when at zero vacuum? I'll then add a second catch can.

 

[Midlife Crises]

but with a one-way valve to prevent pressurised gases inside the intake manifold from entering the crankcase.

With a PD blower, you use the vacuum port on the downstream side of the throttle body for the PCV. Between throttle blade and blower rotor there should never be pressure. The only pressure is after the rotors. The check valve function of the PCV is to prevent a backfire event from blowing the seals out of the engine.

 

[eighty6gt]

Superchargers do not increase blow by gases past the piston rings.

 

[06 T-RED S/C GT]

With a PD blower, you use the vacuum port on the downstream side of the throttle body for the PCV. Between throttle blade and blower rotor there should never be pressure. The only pressure is after the rotors. The check valve function of the PCV is to prevent a backfire event from blowing the seals out of the engine.

On the Saleen VI blower, the intake manifold vacuum port is connected to the PCV port on the driver's side cam cover. The passenger side port is connected downstream to the throttle body. Perhaps I'm not quite understanding where exactly your coming from

Superchargers do not increase blow by gases past the piston rings.

View attachment 77482

So if I'm understanding correctly, elevated cylinder pressure from superchargers do not increase blow by gases past the piston rings?

 

[crjackson]

For anyone interested, there’s a good read on the subject here;
https://www.superchargerforums.com/...ilation-how-to-breathe-when-youre-blown.2472/

 

[Midlife Crises]

On the Saleen VI blower, the intake manifold vacuum port is connected to the PCV port on the driver's side cam cover. The passenger side port is connected downstream to the throttle body. Perhaps I'm not quite understanding where exactly your coming from


So if I'm understanding correctly, elevated cylinder pressure from superchargers do not increase blow by gases past the piston rings?

increasing cylinder pressure improves ring seal by forcing the rings against the cylinder walls and piston lands.

 

[eighty6gt]

On the Saleen VI blower, the intake manifold vacuum port is connected to the PCV port on the driver's side cam cover. The passenger side port is connected downstream to the throttle body. Perhaps I'm not quite understanding where exactly your coming from



So if I'm understanding correctly, elevated cylinder pressure from superchargers do not increase blow by gases past the piston rings?

Not meaningfully.

 

[Midlife Crises]

On the Saleen VI blower, the intake manifold vacuum port is connected to the PCV port on the driver's side cam cover. The passenger side port is connected downstream to the throttle body. Perhaps I'm not quite understanding where exactly your coming from

I think our terms are mixed up. If I hooked the intake manifold to the cam cover it would pressurize the crank case when under boost. Why would I do that? If I hook the blower inlet “after the throttle body” to the cam cover the crank case will only see vacuum or atmosphere depending on throttle position and load.

 

[06 T-RED S/C GT]

Not meaningfully.

So if elevated cylinder pressure from superchargers do not increase blow by gases past the piston rings? Then what else may be causing it? Only other scenario I can think of, is the design of the 3v PCV valve itself

Also is the post quote from Dino Dino Bambino accurate?

The only situation where you'd collect oil in both catch cans is if you have excessive blowby of combustion gases past the piston rings. This can happen in forced induction applications, even in the absence of ring/bore wear, simply because some of the elevated cylinder pressure "leaks" past the rings.

I think our terms are mixed up. If I hooked the intake manifold to the cam cover it would pressurize the crank case when under boost. Why would I do that? If I hook the blower inlet “after the throttle body” to the cam cover the crank case will only see vacuum or atmosphere depending on throttle position and load.

I fully agree about our terms being mixed up lol. More than likely I'm mixing up the blower/vacuum inlet after the "throttle body" with the intake manifold inlet. Perhaps after looking over the images of my Saleen VI blower setup, you can confirm that it is indeed the blower/vacuum inlet after the "throttle body" which is actually hooked up to the catch can and also from the catch can to the driver's side cam cover?

 

[Midlife Crises]

I fully agree about our terms being mixed up lol

I can see a 5/8” hose coming from the blower inlet right behind the throttle body and connected to the catch can. I see you have added a check valve to this line. I can’t fully see the other line from the catch can but it looks like it go to the drivers cam cover. Looks good to me but you don’t need the check valve if the one in the cam cover works. On the passenger side I see the cam cover is connected to the clean air duct in front of the throttle body just like it should be. I also see what looks like a breather on your oil fill neck. That breather will introduce unmetered air into the system rather than pull air through the clean air duct.

 

[eighty6gt]

It's normal for the PCV system to pass oil.

 

[06 T-RED S/C GT]

I can see a 5/8” hose coming from the blower inlet right behind the throttle body and connected to the catch can. I see you have added a check valve to this line. I can’t fully see the other line from the catch can but it looks like it go to the drivers cam cover. Looks good to me but you don’t need the check valve if the one in the cam cover works. On the passenger side I see the cam cover is connected to the clean air duct in front of the throttle body just like it should be. I also see what looks like a breather on your oil fill neck. That breather will introduce unmetered air into the system rather than pull air through the clean air duct.

Yes, that is correct. The 5/8" hose you see in the photo is coming from the blower inlet right behind the throttle body and connected to the catch can. The check valve added to the 5/8" hose line is routed between the blower inlet and catch can. The check valve was included with the UPR catch can and is a one-way directional valve designed to prevent crankcase gasses from being sucked into the blower and also back into the crankcase if I understand correctly? The other line you see, is routed from the catch can to the driver's side cam cover. Prior to adding the one-way check valve, crankcase oil gasses were discovered inside the air intake tube attached directly in front of the throttle body.
Therefore UPR recommended adding the inline one-way check valve for that reason? What you see from the passenger side is also correct, as the cam cover is connected to the clean air duct in front of the throttle body just like it should be. The breather you notice on the oil fill neck, also has a built-in one way check ball valve which is designed to only allow airflow to escape when the crankcase is under pressure, otherwise, the valve remains fully closed when under vacuum. If it is in fact designed to function as C.F.M claims? it shouldn't allow for any unmetered air into the system and preventing air from being pulled through the clean air duct.
At any rate, the only other scenario I can possibly think of which may be causing crankcase oil to build-up inside of the air inlet tube attached directly in front of the throttle body, is either the design of the PCV valve inside the 3v cam cover is flawed or the valve itself just isn't functioning properly and may be defective

It's normal for the PCV system to pass oil.

I can certainly understand it being normal for the PCV system to pass some oil, but not when it's an excessive amount. The main concern as mentioned above was from crankcase oil building up inside the air inlet tube in front of the throttle body and also small amounts around the throttle body itself as well

 

[Midlife Crises]

The check valve was included with the UPR catch can and is a one-way directional valve designed to prevent crankcase gasses from being sucked into the blower and also back into the crankcase if I understand correctly?

No matter how many times I read this sentence I can’t figure out how a one way valve can block flow both ways. You have a redundant check valve. If you installed it so flow can not pass from the cam cover to the blower inlet you have created a blockage and the engine must vent through the breather on the fill neck or blow seals.
Do you have oil in the catch can?

 

[Midlife Crises]

It's normal for the PCV system to pass oil.

Any reciprocating internal combustion engine I have ever seen or heard of has oil mist in the vent gasses. We are just trying to collect it rather than dribble it on the ground.

 

[eighty6gt]

...It goes into the intake manifold and is burned in the cylinders, usually.

 

[Midlife Crises]

...It goes into the intake manifold and is burned in the cylinders, usually.

I have worked on large recipes and gas turbines that used coalescing filters on their crank case or oil tank vents. The filter canisters have a drain line that continuously returns the captured oil to the oil tank. Feeding it to the cylinders is not the only way to deal with oil mist.

 

[06 T-RED S/C GT]

No matter how many times I read this sentence I can’t figure out how a one way valve can block flow both ways. You have a redundant check valve. If you installed it so flow can not pass from the cam cover to the blower inlet you have created a blockage and the engine must vent through the breather on the fill neck or blow seals.
Do you have oil in the catch can?

Perhaps I've got it all backwards then? Maybe the purpose of the one way check valve is to allow flow to pass from the cam cover to the blower inlet whenever vacuum is closed at the blower inlet while the crankcase is under pressure? As it wouldn't make much sense to block airflow to the blower inlet. Therefore, I agree this would in fact create a blockage for which the engine must then be able to vent pressure through the breather on the oil fill neck, otherwise, just as you brought up, the blockage will cause the seals to blow.
All I know for certain, is the inline check valve cannot block flow more than one way. As for the catch can? yes, it does in fact collect oil which gets emptied out at every oil change, but make no mistake, no catch can is able to trap all oil completely. This was also one of the reasons for adding the oil cap breather with built in, one way check ball valve which provides another outlet for venting crankcase pressure when vacuum is closed at the blower inlet and also prevents unmetered air from entering the crankcase.

...It goes into the intake manifold and is burned in the cylinders, usually.

Yes, that is what the purpose of the PCV system is supposedly designed to do

 

[Midlife Crises]

As for the catch can? yes, it does in fact collect oil

Good deal. If there is oil in the catch can, you have flow from the crankcase to the intake and a working system. I think somebody talked you into other parts you don’t need but they’re probably not hurting anything. You are correct. There will always be some oil carryover in a common PCV system.

 

[06 T-RED S/C GT]

Good deal. If there is oil in the catch can, you have flow from the crankcase to the intake and a working system. I think somebody talked you into other parts you don’t need but they’re probably not hurting anything. You are correct. There will always be some oil carryover in a common PCV system.

Most definitely agree on the working system and being talked into parts that aren't really needed