Oil Catch Can Question...
Le Mans Master
Joined: Aug 2003
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From: American Canyon Lethal Injection
Here is my latest hookup to the catch can.
I ran both lines from the valve covers "t'd" into one line going in the top inlet of the catch can and the bottom lne going to the lower inlet of the TB.
The top inlet of the TB is plugged.
I ran both lines from the valve covers "t'd" into one line going in the top inlet of the catch can and the bottom lne going to the lower inlet of the TB.
The top inlet of the TB is plugged.
Le Mans Master
Joined: Dec 2003
Posts: 5,561
Likes: 448
From: Atlanta metro Ga.
Originally Posted by SleeperC5
Here is my latest hookup to the catch can.
I ran both lines from the valve covers "t'd" into one line going in the top inlet of the catch can and the bottom lne going to the lower inlet of the TB.
The top inlet of the TB is plugged.
I ran both lines from the valve covers "t'd" into one line going in the top inlet of the catch can and the bottom lne going to the lower inlet of the TB.
The top inlet of the TB is plugged.
Le Mans Master
Joined: Oct 2002
Posts: 6,799
Likes: 11
From: dudley MA
i have a fuel filter on both lines and a catch can. i still have oil in the intake. no oil from the passenger side valve cover at all. that fuel filter was clean, but the other fuel filter had oil in it and so did the catch can. so the fuel filter is not stopping the oil and neither is the AMW catch can. has any one actually stopped the oil from getting in the intake? should i ditch the fuel filter and try a different type of filter before the catch can? also how do you guys get the oil out of the fast intake to clean it? is it a biatch to take apart?
Le Mans Master
Joined: Aug 2003
Posts: 9,298
Likes: 4
From: American Canyon Lethal Injection
Originally Posted by Dan_the_C5_Man
Where is your "fresh air" source?! This is not a good setup; you've essentially "sealed" the crankcase.
Last edited by SLPRC5; Dec 11, 2006 at 12:48 AM.
Le Mans Master
Joined: Dec 2003
Posts: 5,561
Likes: 448
From: Atlanta metro Ga.
Originally Posted by SleeperC5
OK, what if I "T" back into one of the vacuum lines from the TB outlet that I have capped off? Or how about putting an oil cap with a filter on it like this?
Both of your suggested options have issues;
The first one more or less defeats the "circular" nature of the stock PCV system. The general idea is to allow fresh, metered air into one end of the motor, pull the nasty stuff from the other end. Not so effective if your fresh air source is tied (or in very close proximity) to your vacuum source. Not a lot of opportunity to pull the nasty gases out of the crankcase.
The second option solves the circular issue, but introduces the "un-metered air" issue, i.e. it's an "open" system, you ultimately have air entering the manifold (via the PCV valve) that bypassed the MAF, was not measured and thusly not accounted for. Folks are still debating this one, but it makes sense it's an issue; my motors' idle changes if I pull the dipstick or pop the oil cap while the engine is running, so you decide.
I think the reasonable course of action is to leave the basic GM design as-is, but insert the catch-can in-line to filter out as much oil as is practical, and leave it at that.
Last edited by Dan_the_C5_Man; Dec 11, 2006 at 01:35 AM.
Le Mans Master
Joined: Mar 2002
Posts: 5,955
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From: PNW
Originally Posted by SleeperC5
OK, what if I "T" back into one of the vacuum lines from the TB outlet that I have capped off? Or how about putting an oil cap with a filter on it like this?
It also has an oil catch can between the engine and intake manifold setup in a normal manner.
There is also an open breather/filter setup on the oil filler cap ... why I don't know since this guy already has the fresh air line.
By doing that, he is introducing un-metered air into the intake manifold. Guess some guys think that the more vents and filters you have the better! 
Last edited by ZeeOSix; Dec 11, 2006 at 01:54 AM.
Melting Slicks
Joined: Oct 2006
Posts: 2,236
Likes: 0
From: Suisun City Ca
Originally Posted by Dan_the_C5_Man
Check out my post (#24) in this thread..
Both of your suggested options have issues;
The first one more or less defeats the "circular" nature of the stock PCV system. The general idea is to allow fresh, metered air into one end of the motor, pull the nasty stuff from the other end. Not so effective if your fresh air source is tied (or in very close proximity) to your vacuum source. Not a lot of opportunity to pull the nasty gases out of the crankcase.
The second option solves the circular issue, but introduces the "un-metered air" issue, i.e. it's an "open" system, you ultimately have air entering the manifold (via the PCV valve) that bypassed the MAF, was not measured and thusly not accounted for. Folks are still debating this one, but it makes sense it's an issue; my motors' idle changes if I pull the dipstick or pop the oil cap while the engine is running, so you decide.
I think the reasonable course of action is to leave the basic GM design as-is, but insert the catch-can in-line to filter out as much oil as is practical, and leave it at that.
Both of your suggested options have issues;
The first one more or less defeats the "circular" nature of the stock PCV system. The general idea is to allow fresh, metered air into one end of the motor, pull the nasty stuff from the other end. Not so effective if your fresh air source is tied (or in very close proximity) to your vacuum source. Not a lot of opportunity to pull the nasty gases out of the crankcase.
The second option solves the circular issue, but introduces the "un-metered air" issue, i.e. it's an "open" system, you ultimately have air entering the manifold (via the PCV valve) that bypassed the MAF, was not measured and thusly not accounted for. Folks are still debating this one, but it makes sense it's an issue; my motors' idle changes if I pull the dipstick or pop the oil cap while the engine is running, so you decide.
I think the reasonable course of action is to leave the basic GM design as-is, but insert the catch-can in-line to filter out as much oil as is practical, and leave it at that.
The first set up that Deno posted is fine the Idea is to extract positive pressure from the crank case using the vacuum in the manifold. He does not have an airpump that pushes air into the drivers side valve cover so that it can exit the passenger side. Instead he is running two vacuum lines to pull out of both valve covers ANY positive pressure in the crank will exit via those two lines through the catch can and into the intake. On my car I run breathers no PCV system infact the idea that you need a pcv system in the way you are explaining it is not 100% correct. You need to relieve positive crank pressure more than anything. A stock pcv system is in place to push the "nasty stuff" through the intake so that it can be burned in the engine for no other reason than emissions. In a race application you would do something similar to what deno has done but instead of going into the intake you would go into a vacuum pump and actualy put negative pressure in the crank which will gain power
I agree 100% that the second setup that Deno posted does not work and would basicaly be a consistant vacuum leak allowing un metered air in after the MAF.
Melting Slicks
Joined: Oct 2006
Posts: 2,236
Likes: 0
From: Suisun City Ca
Originally Posted by pdd000
i have a fuel filter on both lines and a catch can. i still have oil in the intake. no oil from the passenger side valve cover at all. that fuel filter was clean, but the other fuel filter had oil in it and so did the catch can. so the fuel filter is not stopping the oil and neither is the AMW catch can. has any one actually stopped the oil from getting in the intake? should i ditch the fuel filter and try a different type of filter before the catch can? also how do you guys get the oil out of the fast intake to clean it? is it a biatch to take apart?
to clean the fast the best thing to do is remove it and spray a ton of brake clean in it. On my car I have 0 oil in the intake because I removed all lines leading back into the intake and put breathers on my valve covers. The car makes plenty of power N/A and there is only one negative.... the slight smell of oil sometimes when pulling up to a stop. I am looking at a vacuum pump set up right now and I will let you know how that works out should be an interesting test!
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Le Mans Master
Joined: Dec 2003
Posts: 5,561
Likes: 448
From: Atlanta metro Ga.
Originally Posted by csixs
The first set up that Deno posted is fine the Idea is to extract positive pressure from the crank case using the vacuum in the manifold. He does not have an airpump that pushes air into the drivers side valve cover so that it can exit the passenger side. Instead he is running two vacuum lines to pull out of both valve covers ANY positive pressure in the crank will exit via those two lines through the catch can and into the intake. On my car I run breathers no PCV system infact the idea that you need a pcv system in the way you are explaining it is not 100% correct. You need to relieve positive crank pressure more than anything. A stock pcv system is in place to push the "nasty stuff" through the intake so that it can be burned in the engine for no other reason than emissions. In a race application you would do something similar to what deno has done but instead of going into the intake you would go into a vacuum pump and actualy put negative pressure in the crank which will gain power
I agree 100% that the second setup that Deno posted does not work and would basicaly be a consistant vacuum leak allowing un metered air in after the MAF.
I agree 100% that the second setup that Deno posted does not work and would basicaly be a consistant vacuum leak allowing un metered air in after the MAF.
There is a well-known PCV issue that Toyota (of all manufactures) had with a series of motors. Basically they "blew it" on the location and internal routing of the PCV system, causing sludge to build up, ultimately starving motor bearings and other components of oil. Here's a link; I hope you are frequently changing your oil. Enjoy. http://yotarepair.com/Sludge_Zone.html http://www.schleeter.com/oil-sludge.htm
Last edited by Dan_the_C5_Man; Dec 11, 2006 at 02:45 AM.
Melting Slicks
Joined: Oct 2006
Posts: 2,236
Likes: 0
From: Suisun City Ca
Originally Posted by Dan_the_C5_Man
Assuming a "tight" motor, were will the air to displace the vacuum from the manifold come from?
Let's for a moment agree for the sake of this argument the above isn't an issue.. I do disagree with your statement that a PCV system is "only" for emissions; clearly that is its primary purpose, BUT it also serves to evacuate those "nasty" gases that can (and will) cause sludge in the oil, clogging oil galleries, etc.
There is a well-known PCV issue that Toyota (of all manufactures) had with a series of motors. Basically they "blew it" on the location and internal routing of the PCV system, causing sludge to build up, ultimately starving motor bearings and other components of oil. Here's a link; I hope you are frequently changing your oil. Enjoy. http://yotarepair.com/Sludge_Zone.html http://www.schleeter.com/oil-sludge.htm
Let's for a moment agree for the sake of this argument the above isn't an issue.. I do disagree with your statement that a PCV system is "only" for emissions; clearly that is its primary purpose, BUT it also serves to evacuate those "nasty" gases that can (and will) cause sludge in the oil, clogging oil galleries, etc.
There is a well-known PCV issue that Toyota (of all manufactures) had with a series of motors. Basically they "blew it" on the location and internal routing of the PCV system, causing sludge to build up, ultimately starving motor bearings and other components of oil. Here's a link; I hope you are frequently changing your oil. Enjoy. http://yotarepair.com/Sludge_Zone.html http://www.schleeter.com/oil-sludge.htm
And I am by no means easy on my motor, I do not beat on it but I use it hard. I take it to the road tracks drag strip and alot of "road" events I usualy have the car on the dyno 10-15 times a week as well.
I have had not 1 problem with my oil becoming sludgey I have tried 4-5 different brands of oil as well as different weight of oil to check hp vs. viscocity ect. All of the oils I have tested I also examined after removing the oil and like I said before have no issues.
to put these links up towards toyota is odd because it clearly states a 10000 mile oil change is the cause of the sludge
From one of your links
What is oil sludge?
Oil sludge is the breakdown product of over-stressed oil in your engine.
Oil that is stressed by contaminants and oxidation-or has to work thousands of miles longer than it was designed to-will break down into a gel that sticks to your engine parts. As the sludge sticks, there is less good oil to circulate and do its protective job. This coating of gel also stores heat instead of releasing it which stresses the radiator and cooling system.
Oil sludge is the breakdown product of over-stressed oil in your engine.
Oil that is stressed by contaminants and oxidation-or has to work thousands of miles longer than it was designed to-will break down into a gel that sticks to your engine parts. As the sludge sticks, there is less good oil to circulate and do its protective job. This coating of gel also stores heat instead of releasing it which stresses the radiator and cooling system.
So why don't all cars suffer from sludge?
Some car makers stay with the standard 3-month/3,000 mile oil change interval. Others, such as BMW's longer interval, rarely cause any problems. Why? Their new engine designs call for a 7 or 8 quart capacity, almost twice that of the average car—and they specify full synthetic motor oil.
In addition, some drivers protect their cars by ignoring the recommended longer interval and changing their motor oil every 3,000 miles. These drivers ask for high-quality oil and filters, and keep up with other maintenance schedules.
Remember—any car can suffer an oil sludge problem, and some manufacturers more than others due to various design differences. It's to your advantage to get a technician's advice on what interval your engine and driving habits REALLY requires, and take matters into your own hands
Some car makers stay with the standard 3-month/3,000 mile oil change interval. Others, such as BMW's longer interval, rarely cause any problems. Why? Their new engine designs call for a 7 or 8 quart capacity, almost twice that of the average car—and they specify full synthetic motor oil.
In addition, some drivers protect their cars by ignoring the recommended longer interval and changing their motor oil every 3,000 miles. These drivers ask for high-quality oil and filters, and keep up with other maintenance schedules.
Remember—any car can suffer an oil sludge problem, and some manufacturers more than others due to various design differences. It's to your advantage to get a technician's advice on what interval your engine and driving habits REALLY requires, and take matters into your own hands
So yes I agree change your oil regularly and please dont make it sound like not running a factory PCV system will ruin your motor it is just not as harsh as you are making it out to be. I deal with these cars every day and I have seen some interesting pcv set ups and still no blown motors..........
and there is not a need for air to displace the air being sucked out with vacuum it would creat a lower pressure in the crank which is good for the motor.
Last edited by Robert@Advanced Dyno; Dec 11, 2006 at 03:03 AM.
Melting Slicks
Joined: Aug 2005
Posts: 3,398
Likes: 2
We have 2 street/track cars that dont run a pcv system at all with no ill effects ever. Ive never run pcv systems on my race cars or performance street cars either. I dont believe in re-admitting unburned "crap" back into my intake charge at all! If it bothers people they can run a seperate vacuum pump to evacuate pressure/blowby into a catch reservoir.
There are hundreds of different designed catch cans/oil tanks on the market. The ones that just came out by a few vendors on here are nothing new and in fact the design lacks a few things that are already implemented on other catch cans (such as a sight glass).
There are hundreds of different designed catch cans/oil tanks on the market. The ones that just came out by a few vendors on here are nothing new and in fact the design lacks a few things that are already implemented on other catch cans (such as a sight glass).
Last edited by briann510; Dec 11, 2006 at 04:43 AM.
Le Mans Master
Joined: Dec 2003
Posts: 5,561
Likes: 448
From: Atlanta metro Ga.
I think it's safe to say the vast majority of us here use the DIC oil life monitor to some extent (I let mine get to around 35% percent before I change it) which equates to appox. 5,000~6,000 miles, which is a perfectly reasonable change interval for a full synthetic.
If you are changing your oil every 3K miles, then yes I agree you won't see any negative effects from removing the PCV system, but then again this is not the "norm", and could get quite expensive depending on how many miles you drive per year. If you read the articles in their entirety you'll also see a pattern indicating a poor PCV system design. At any rate, you seem to be aware of the possible pitfalls and have a solution to counter them, so
for you.
If you are changing your oil every 3K miles, then yes I agree you won't see any negative effects from removing the PCV system, but then again this is not the "norm", and could get quite expensive depending on how many miles you drive per year. If you read the articles in their entirety you'll also see a pattern indicating a poor PCV system design. At any rate, you seem to be aware of the possible pitfalls and have a solution to counter them, so
for you.
Melting Slicks
Joined: Oct 2006
Posts: 2,236
Likes: 0
From: Suisun City Ca
Originally Posted by Dan_the_C5_Man
I think it's safe to say the vast majority of us here use the DIC oil life monitor to some extent (I let mine get to around 35% percent before I change it) which equates to appox. 5,000~6,000 miles, which is a perfectly reasonable change interval for a full synthetic.
If you are changing your oil every 3K miles, then yes I agree you won't see any negative effects from removing the PCV system, but then again this is not the "norm", and could get quite expensive depending on how many miles you drive per year. If you read the articles in their entirety you'll also see a pattern indicating a poor PCV system design. At any rate, you seem to be aware of the possible pitfalls and have a solution to counter them, so for you.
If you are changing your oil every 3K miles, then yes I agree you won't see any negative effects from removing the PCV system, but then again this is not the "norm", and could get quite expensive depending on how many miles you drive per year. If you read the articles in their entirety you'll also see a pattern indicating a poor PCV system design. At any rate, you seem to be aware of the possible pitfalls and have a solution to counter them, so
for you.
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 232
From: SoCal
Originally Posted by csixs
On my car I run breathers no PCV system ......
And you have breathers where exactly and what kind.
I am assuming since you run so frequently on the dyno you have checked for HP differences between the various setups?? How about pinging/detonation issues.....I assume you should have less of these as well.
DH
Melting Slicks
Joined: Oct 2006
Posts: 2,236
Likes: 0
From: Suisun City Ca
Originally Posted by Dirty Howie
So you have capped off the TB and Intake mainifold....correct??
And you have breathers where exactly and what kind.
I am assuming since you run so frequently on the dyno you have checked for HP differences between the various setups?? How about pinging/detonation issues.....I assume you should have less of these as well.
DH
And you have breathers where exactly and what kind.
I am assuming since you run so frequently on the dyno you have checked for HP differences between the various setups?? How about pinging/detonation issues.....I assume you should have less of these as well.
DH
I am runnign 12:1 compression and can run on 91 octane gas, before doing this I was not able to run as much timing because the oil and "nasty stuff" was casuing detonation.
Just swaping the pcv with breathers will not add HP unless you are having problems such as detonation. If you remove the pcv, clean your intake runners out ect. and work on your tune a bit there is some power to be had simply by reducing the knock. This aslo could be looked at as making your set up safer
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 232
From: SoCal
Originally Posted by csixs
the breathers are on the valve covers and yes this has helped with knock alot, yes I have capped off all of my lines to the tb/intake
I am runnign 12:1 compression and can run on 91 octane gas, before doing this I was not able to run as much timing because the oil and "nasty stuff" was casuing detonation.
Just swaping the pcv with breathers will not add HP unless you are having problems such as detonation. If you remove the pcv, clean your intake runners out ect. and work on your tune a bit there is some power to be had simply by reducing the knock. This aslo could be looked at as making your set up safer
I am runnign 12:1 compression and can run on 91 octane gas, before doing this I was not able to run as much timing because the oil and "nasty stuff" was casuing detonation.
Just swaping the pcv with breathers will not add HP unless you are having problems such as detonation. If you remove the pcv, clean your intake runners out ect. and work on your tune a bit there is some power to be had simply by reducing the knock. This aslo could be looked at as making your set up safer
Are you running small breathers off the valve cover vent tubes or have you modified the valve covers.
How bad is the oil smell???
DH
Melting Slicks
Joined: Oct 2006
Posts: 2,236
Likes: 0
From: Suisun City Ca
Originally Posted by Dirty Howie
I am getting HPTuner in a few weeks. I will be monitoring my KR with different setups. And if I can run more timing with no KR without the PCV then away it goes.
Are you running small breathers off the valve cover vent tubes or have you modified the valve covers.
How bad is the oil smell???
DH
Are you running small breathers off the valve cover vent tubes or have you modified the valve covers.
How bad is the oil smell???
DH
the oil in your intake runners will need to be cleaned out first before you notice the biggest improvement.
and dont just add the timing because it will take it add it if it makes more power with it.
oil smell is not that bad heck down where you live you may not even notice it!!!!(not an insult i would prefer to live down there myself)
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 232
From: SoCal
DH
Melting Slicks
Joined: Oct 2006
Posts: 2,236
Likes: 0
From: Suisun City Ca
Yes you will have to remove the intake manifold but you will only have to do it once!
Does the intake manifold need to be removed or is there another way??
Understood. But I have had some removed recently due to pinging!
I was running a breather on the valve vent tubes before I found out about unmeterred air so I got some oil smell. I assume it would be worse with the PCV line blocked.
DH
Understood. But I have had some removed recently due to pinging!
I was running a breather on the valve vent tubes before I found out about unmeterred air so I got some oil smell. I assume it would be worse with the PCV line blocked.
DH
Le Mans Master
Joined: Oct 2005
Posts: 7,088
Likes: 1,829
From: Metro Detroit Michigan
Sorry, I have to put this up every 50th catch can thread or so.
Seriously, the only way to eliminate all liquid in the intake manifold is to vent the crankcase to the atmosphere.
The liquid in the intake consists of two components:
Oil, which is in droplet form, and can be mostly eliminated with a coalescing filter.
True vapor, which can only be distilled or condensed.
No matter how good your catch can, it will run warm, and most vapor will go through. Vapor from blowby (unburned fuel) will bypass it and condense on the cooler intake manifold surfaces. Some of what acculates in the intake is oil, and some is combustion blowby condensate.
Eliminating the oil mist will not keep your intake from get wet.
Seriously, the only way to eliminate all liquid in the intake manifold is to vent the crankcase to the atmosphere.
The liquid in the intake consists of two components:
Oil, which is in droplet form, and can be mostly eliminated with a coalescing filter.
True vapor, which can only be distilled or condensed.
No matter how good your catch can, it will run warm, and most vapor will go through. Vapor from blowby (unburned fuel) will bypass it and condense on the cooler intake manifold surfaces. Some of what acculates in the intake is oil, and some is combustion blowby condensate.
Eliminating the oil mist will not keep your intake from get wet.