Oil In Hose Going To Throttle Body.
Registered User
Joined: May 2001
Posts: 159
From: Rockledge, Florida USA
Ah...very good point Injuneer! Now that you mention it, I recall that my airfoil mounts through the hole that feeds the TB cover plate volume and I remember trying to figure out how it all fit together without plugging that hole. Turns out that with my airfoil, that particular hole is blocked about 50% due to the airfoil mount. I don't know what affect that has had on the PCV airflow but I can say that my TB cover plate volume is free from oil.
RobY
95Z28
RobY
95Z28
Registered User
Joined: Feb 2003
Posts: 1,853
From: Christiansburg, VA
Originally posted by pelebkf
Okay then is it better to have a breather in the value cover considering that my airfoil also covers most of the air passage?
Okay then is it better to have a breather in the value cover considering that my airfoil also covers most of the air passage?
jesse
Registered User
Joined: Jan 2004
Posts: 4
From: Seattle, WA
Lots of good info here. Though it was repeated many, many times.
We have had the same discussion going on over at the ImpalaSSForum.
What I suggest to keep the "metered air" system operation while preventing oil from being "pushed" into the throttle body, and allowing for ventilation of any crank case "pressure" is this:
One way valve installed in the hose from the throttle body to the passenger side valve cover which allows clean air to flow into the valve cover only.
An additional hose from a tapped fitting in one of the valve covers would be connected to an "evac" tube in a header collector. This would also have an in-line, one way valve, allowing crankcase gases to be drawn out during a "positive pressure" situation, while preventing burnt exhaust gases from being drawn in during idle.
Now, I may be wrong here, but I would expect the closed PCV system to function as normal and pull the same amount of "metered air" through the engine. Now, I know someone is thinking; "What about the "metered air" being drawn out through the collectors via the EVAC fitting?". The one way valve should be a type only opened with pressure, "positive pressure" from the crank case gases. This would allow the pcv system to circulate all "metered air" and if positive pressure becomes an issue and the PCV system can not keep up, the one way valve in the EVAC line will be forced open and the excess positive pressure (crank case gas) will be forced out as well as drawn out by the vacuum in the collectors.
What do you guys think?
We have had the same discussion going on over at the ImpalaSSForum.
What I suggest to keep the "metered air" system operation while preventing oil from being "pushed" into the throttle body, and allowing for ventilation of any crank case "pressure" is this:
One way valve installed in the hose from the throttle body to the passenger side valve cover which allows clean air to flow into the valve cover only.
An additional hose from a tapped fitting in one of the valve covers would be connected to an "evac" tube in a header collector. This would also have an in-line, one way valve, allowing crankcase gases to be drawn out during a "positive pressure" situation, while preventing burnt exhaust gases from being drawn in during idle.
Now, I may be wrong here, but I would expect the closed PCV system to function as normal and pull the same amount of "metered air" through the engine. Now, I know someone is thinking; "What about the "metered air" being drawn out through the collectors via the EVAC fitting?". The one way valve should be a type only opened with pressure, "positive pressure" from the crank case gases. This would allow the pcv system to circulate all "metered air" and if positive pressure becomes an issue and the PCV system can not keep up, the one way valve in the EVAC line will be forced open and the excess positive pressure (crank case gas) will be forced out as well as drawn out by the vacuum in the collectors.
What do you guys think?
Registered User
Joined: Nov 2001
Posts: 3,515
From: Kansas
Originally posted by Injuneer
Not so sure that statement is completely correct. The air supply (which is eventually pulled through the crankcase and out the PCV valve), to the line from the TB to the passenger side valve cover comes from the upper triangular space, in front of, and above the throttle blades. The hole is on the top of the triangular space, and opens directly into the chamber under the TB cover plate. It is conceivable that a poorly designed air foil could close that space off, and limit the air flow that sweeps vapors from the crankcase.
Not so sure that statement is completely correct. The air supply (which is eventually pulled through the crankcase and out the PCV valve), to the line from the TB to the passenger side valve cover comes from the upper triangular space, in front of, and above the throttle blades. The hole is on the top of the triangular space, and opens directly into the chamber under the TB cover plate. It is conceivable that a poorly designed air foil could close that space off, and limit the air flow that sweeps vapors from the crankcase.
Registered User
Joined: Jul 2003
Posts: 1,103
From: Hawaii
and people just blow me off
Stop acting so Vaginal and be a man!!
Just kidding man, I swear I am only kidding you.
But give Cesar what belongs to Cesar and if you have said it too before, then I can tell you with all honesty
"You are the MAN too" my friend.
Administrator
Joined: Nov 1998
Posts: 71,124
From: Hell was full so they sent me to NJ
Originally posted by turbo_Z
I have been saying that for a long time and people just blow me off thinking I have no clue whats going on but when you say it they all take a bow and sit back admiring your genius. Not that I am hanging crap on you Fred... its just frustrating when people thank you and Shoebox for answers other people supply too.
I have been saying that for a long time and people just blow me off thinking I have no clue whats going on but when you say it they all take a bow and sit back admiring your genius. Not that I am hanging crap on you Fred... its just frustrating when people thank you and Shoebox for answers other people supply too.
Registered User
Joined: Jun 2003
Posts: 112
To tell you the truth Fred many times I only reason I post on any thread it is because you are shoebox is on it! Your information that you provide is always right on target and I love hearing your responses to the many questions that people have asked.
This is the only reason I asked you about the airfoil and the breather valve on the cover. I think that this is a legit question and I would love to hear what you have to say about it. I plan on keeping my airfoil I just wanted to know if it is better to keep it open with a breather or have it closed by the airfoil.
I have always apreciated your information Fred and you are the man.
This is the only reason I asked you about the airfoil and the breather valve on the cover. I think that this is a legit question and I would love to hear what you have to say about it. I plan on keeping my airfoil I just wanted to know if it is better to keep it open with a breather or have it closed by the airfoil.
I have always apreciated your information Fred and you are the man.
Registered User
Joined: Dec 2003
Posts: 25
From: Texas
I have had this problem also. My engine had been beat when I bought it three years ago with 53000 miles on it. But the funny thing is it NEVER uses a drop of oil between changes. And theres no smoke or blow by that I can see.
I think I'm goig to replace the pcv grommet again as it is a loose fit. I pit the little in line filter from Auto Zone in and it has helped a lot. High miles, low miles, some do, some don,t. I kinda think when some engines get a little wear the pcv system just cant handle it.
The only reason it worried me was it was gumming up my intake, and I read the oil would lower the octane rating of the fuel.
I think I'm goig to replace the pcv grommet again as it is a loose fit. I pit the little in line filter from Auto Zone in and it has helped a lot. High miles, low miles, some do, some don,t. I kinda think when some engines get a little wear the pcv system just cant handle it.
The only reason it worried me was it was gumming up my intake, and I read the oil would lower the octane rating of the fuel.
Registered User
Joined: Oct 1999
Posts: 448
From: DAPHNE,AL USA
Originally posted by Devil.Dog
Lots of good info here. Though it was repeated many, many times.
We have had the same discussion going on over at the ImpalaSSForum.
What I suggest to keep the "metered air" system operation while preventing oil from being "pushed" into the throttle body, and allowing for ventilation of any crank case "pressure" is this:
One way valve installed in the hose from the throttle body to the passenger side valve cover which allows clean air to flow into the valve cover only.
An additional hose from a tapped fitting in one of the valve covers would be connected to an "evac" tube in a header collector. This would also have an in-line, one way valve, allowing crankcase gases to be drawn out during a "positive pressure" situation, while preventing burnt exhaust gases from being drawn in during idle.
Now, I may be wrong here, but I would expect the closed PCV system to function as normal and pull the same amount of "metered air" through the engine. Now, I know someone is thinking; "What about the "metered air" being drawn out through the collectors via the EVAC fitting?". The one way valve should be a type only opened with pressure, "positive pressure" from the crank case gases. This would allow the pcv system to circulate all "metered air" and if positive pressure becomes an issue and the PCV system can not keep up, the one way valve in the EVAC line will be forced open and the excess positive pressure (crank case gas) will be forced out as well as drawn out by the vacuum in the collectors.
What do you guys think?
Lots of good info here. Though it was repeated many, many times.
We have had the same discussion going on over at the ImpalaSSForum.
What I suggest to keep the "metered air" system operation while preventing oil from being "pushed" into the throttle body, and allowing for ventilation of any crank case "pressure" is this:
One way valve installed in the hose from the throttle body to the passenger side valve cover which allows clean air to flow into the valve cover only.
An additional hose from a tapped fitting in one of the valve covers would be connected to an "evac" tube in a header collector. This would also have an in-line, one way valve, allowing crankcase gases to be drawn out during a "positive pressure" situation, while preventing burnt exhaust gases from being drawn in during idle.
Now, I may be wrong here, but I would expect the closed PCV system to function as normal and pull the same amount of "metered air" through the engine. Now, I know someone is thinking; "What about the "metered air" being drawn out through the collectors via the EVAC fitting?". The one way valve should be a type only opened with pressure, "positive pressure" from the crank case gases. This would allow the pcv system to circulate all "metered air" and if positive pressure becomes an issue and the PCV system can not keep up, the one way valve in the EVAC line will be forced open and the excess positive pressure (crank case gas) will be forced out as well as drawn out by the vacuum in the collectors.
What do you guys think?
except im using my smog pump at WOT to pull vacum
Registered User
Joined: Jan 2004
Posts: 4
From: Seattle, WA
SILVERZZ28,
so you are using a one way valve? What brand? Source? Price? Also, if the valve works like the PCV valve then there is still the issue with pulling metered air out of the closed loop. Or are you using a pressure sensitive valve like I suggested? This way it remains closed unless the crank case gases exceed the capability of the PCV valve? If so, again i ask: what brand? Source? price?
Also, the airpump is only on for the first few minutes at start-up. How are you using it in this manner? Did you hard wire it to a hot lead so it remains on at all times?
More info please.
My engine should be about ready for shipping and I'm looking forward to getting it back in the car and install every safety feature powsible to insure it's life. The second time around!
Thanks.
so you are using a one way valve? What brand? Source? Price? Also, if the valve works like the PCV valve then there is still the issue with pulling metered air out of the closed loop. Or are you using a pressure sensitive valve like I suggested? This way it remains closed unless the crank case gases exceed the capability of the PCV valve? If so, again i ask: what brand? Source? price?
Also, the airpump is only on for the first few minutes at start-up. How are you using it in this manner? Did you hard wire it to a hot lead so it remains on at all times?
More info please.
My engine should be about ready for shipping and I'm looking forward to getting it back in the car and install every safety feature powsible to insure it's life. The second time around!
Thanks.
Registered User
Joined: Dec 1998
Posts: 209
Originally posted by Devil.Dog
Lots of good info here. Though it was repeated many, many times.
We have had the same discussion going on over at the ImpalaSSForum.
What I suggest to keep the "metered air" system operation while preventing oil from being "pushed" into the throttle body, and allowing for ventilation of any crank case "pressure" is this:
One way valve installed in the hose from the throttle body to the passenger side valve cover which allows clean air to flow into the valve cover only.
An additional hose from a tapped fitting in one of the valve covers would be connected to an "evac" tube in a header collector. This would also have an in-line, one way valve, allowing crankcase gases to be drawn out during a "positive pressure" situation, while preventing burnt exhaust gases from being drawn in during idle.
Now, I may be wrong here, but I would expect the closed PCV system to function as normal and pull the same amount of "metered air" through the engine. Now, I know someone is thinking; "What about the "metered air" being drawn out through the collectors via the EVAC fitting?". The one way valve should be a type only opened with pressure, "positive pressure" from the crank case gases. This would allow the pcv system to circulate all "metered air" and if positive pressure becomes an issue and the PCV system can not keep up, the one way valve in the EVAC line will be forced open and the excess positive pressure (crank case gas) will be forced out as well as drawn out by the vacuum in the collectors.
What do you guys think?
Lots of good info here. Though it was repeated many, many times.
We have had the same discussion going on over at the ImpalaSSForum.
What I suggest to keep the "metered air" system operation while preventing oil from being "pushed" into the throttle body, and allowing for ventilation of any crank case "pressure" is this:
One way valve installed in the hose from the throttle body to the passenger side valve cover which allows clean air to flow into the valve cover only.
An additional hose from a tapped fitting in one of the valve covers would be connected to an "evac" tube in a header collector. This would also have an in-line, one way valve, allowing crankcase gases to be drawn out during a "positive pressure" situation, while preventing burnt exhaust gases from being drawn in during idle.
Now, I may be wrong here, but I would expect the closed PCV system to function as normal and pull the same amount of "metered air" through the engine. Now, I know someone is thinking; "What about the "metered air" being drawn out through the collectors via the EVAC fitting?". The one way valve should be a type only opened with pressure, "positive pressure" from the crank case gases. This would allow the pcv system to circulate all "metered air" and if positive pressure becomes an issue and the PCV system can not keep up, the one way valve in the EVAC line will be forced open and the excess positive pressure (crank case gas) will be forced out as well as drawn out by the vacuum in the collectors.
What do you guys think?
At idle and part throttle, were vaccuum is high, and blowby is realatively low, blowby is purged via the PCV valve. Replacement air may or may not be made up via the passenger-side breather. It depends on how much blowby is created for the given conditions.
Under mid to WOT conditions, where vaccuum is low, and blowby is relatively high, blowby is purged via the passenger-side breather upstream of the TB.
So the direction of flow through the passenger-side BREAThER CHANGES depending on the condition. The direction of flow through the PCV valve is ONE-WAY.
The PVC valve is not just a valve, but also an orifice that limits the amount of flow during idle. When the throttle is opened and manifold vaccuum drops, very little blowby will flow thru the PVC valve. But the the blowby is high, the passenger-side breather tube has no restriction, and it is now expsed to some vaccuum. Its the path of least resistance, and does a good job of purging the crancase.
Modifying the PCV "System" is not a good idea, unless you really understand it. For example, adding an inline filter to the passenger-side breather might reduce the amount of oil entering the TB, but it also might reduce the amount of blowby purged during WOT. Also, depending on where it is mounted, it may prevent oil from draining back into the valve cover. I haven't looked at the filters mentioned above, but a better solution might be a vapor separator - basically an inline cannister with no resistance that allows the oil to collect and drain back to the valve cover. I've seen these used on the 240Z's when autocrossed - apparently they suck a lot of oil through thier breather.
Registered User
Joined: Oct 1999
Posts: 448
From: DAPHNE,AL USA
Im using the factory smog pump and I have it wired to a WOT switch. The pump has a 1 way valve also. I am using this with the factory PVC system too. Its plumbed into the drivers side valve cover with a baffle on the inside. Hope this helps
Registered User
Joined: Jan 2004
Posts: 4
From: Seattle, WA
Thanks guys. It almost seems like the best solution is to leave everything alone!
PGR,
as I was reading your post my paint gun and air compressor came to mind. The water separator does not restrict air flow in any way but does purge the water from the system (so to speak). I just installed a small ($15.00) separator on my compressor at home to do a couple small jobs around the house. I wonder how this would work with oil if mounted in-line between the throttle body and valve cover? According to the marking on the side, it IS directional. I had acidentally installed it backwards and it did NOT separate the water out until I turned it around. But it did not effect airflow or pressure that I could notice.
Anyone have any thoughts on this?
PGR,
as I was reading your post my paint gun and air compressor came to mind. The water separator does not restrict air flow in any way but does purge the water from the system (so to speak). I just installed a small ($15.00) separator on my compressor at home to do a couple small jobs around the house. I wonder how this would work with oil if mounted in-line between the throttle body and valve cover? According to the marking on the side, it IS directional. I had acidentally installed it backwards and it did NOT separate the water out until I turned it around. But it did not effect airflow or pressure that I could notice.
Anyone have any thoughts on this?
Registered User
Joined: Feb 2000
Posts: 1,445
From: Seattle, WA
I dunno... the pressure difference between an N/A manifold and a air compressor is rather signifigant. depends on the design I guess. Is this one of the water traps that have a ball in a tube that relies on pressure to push the ball up (for flow to occur), and the ball closes the valve when reverse pressure is applied? I doubt those would work well in the underhood environment... but a floating-disc design, or any design usable for low pressures should work fine.