HELP, 418 has to much crankcase pressure, blowing out everywher!!!!
04-08-2012, 08:55 PM
#61
The higher flowing air inside your intake system actually creates a low pressure system that the higher pressure inside the engine is drawn to. The air does not push its way into your engine via the PCV system. That is how the PCV system draws excess crank pressure and oil vapors from your crankcase and into the intake stream for it to be reburned and relieved. Any air that is taken in by the PCV system is not accounted for in the standard VE calculations, that is why they have orifices on the valve covers and for the valley cover. So they can slow down the amount of transfer. This is how a downdraft or exhaust tube works also. The higher the pressure is, the faster it works.
You are mistaken on how a pcv system works in the first place. If you are running your engine at idle with the one pcv hose running from your pass valve cover to your TB and you take the cap off, you should notice some odd things. That is unless when the car was tuned you already had breathers on it. Then the airflow readings will be skewed in the wrong direction to try to take into account that unaccounted for air.
Let a newer dodge run then take the oil cap off it and see what happens.
You know how I know that? Because I did it.
Do not worry yourself Diet Coke, I will def test this whole theory out this coming week.
What I dont understand is that if your engine was running so good without a catch can, then why would you spend the extra money and cobble up your engine bay with a catch can then 3 breathers. Maybe there is something else you just arent saying.
You are mistaken on how a pcv system works in the first place. If you are running your engine at idle with the one pcv hose running from your pass valve cover to your TB and you take the cap off, you should notice some odd things. That is unless when the car was tuned you already had breathers on it. Then the airflow readings will be skewed in the wrong direction to try to take into account that unaccounted for air.
Let a newer dodge run then take the oil cap off it and see what happens.
You know how I know that? Because I did it.
Do not worry yourself Diet Coke, I will def test this whole theory out this coming week.
What I dont understand is that if your engine was running so good without a catch can, then why would you spend the extra money and cobble up your engine bay with a catch can then 3 breathers. Maybe there is something else you just arent saying.
The catch can is to keep oil out of the intake.... the standard reason for using one. There is no hose from the VC to the intake tube. It got replaced with *gasp* a breather! I don't understand why this is so hard for you to comprehend
04-08-2012, 09:21 PM
#64
Its not about yours either, and it not MY engine. Its one of my friends. No need to be mad and throw a fit. Ill lay off you for now.
The fact of the matte is, his car should still not be pushing oil through the breather that he has also. The air should be filtered either way and have the same restriction by routing it through a catch can from top out the side or in the side and out the top. Unless it has a check valve, which most do not.
OP how much oil does your catch can have in it after running it around for a day or so?
The fact of the matte is, his car should still not be pushing oil through the breather that he has also. The air should be filtered either way and have the same restriction by routing it through a catch can from top out the side or in the side and out the top. Unless it has a check valve, which most do not.
OP how much oil does your catch can have in it after running it around for a day or so?
04-09-2012, 01:58 PM
#66
Hey look who is being a know it all dick... in this thread you do make some valid points but it looks like your know it all ego is getting in the way again.
The most effective way of pulling crank case pressure is using a vacuum pump and NOT recycling it into the intake stream. The oil will burn and will cause knock.
While the factory PCV does okay at best on a stock engine. It does a poor job once the cubic inches/piston speed increases, blow by from low tension or larger gapped rings and power adders. The factory has installed a PCV system due to emissions first and foremost and it does decrease crank case pressure to some degree. So it was a win win for the OEM.
Now ask your self why your PCV system is pushing oil. It is because the system isn't adequate and there is an airflow restriction. This is where breathers or a vacuum pump comes into play.
Now lets talk about this unmetered air you reference when running a breather. The engine will pull air from the path of least resistance. If it happens to be either through the PCV or the breather, it does not matter! It is all unmetered! I have tuned my fair share of LS vehicles and I have yet to see any noticeable changes in fueling error just by adding a breather.
Things can be simple and work... KISS- Keep It Simple Stupid. In all different motor sports from 2 stroke to 4 they run breathers... Why? Because it is simple and it works.
James like we talked about on the phone... Compression and leak down test. This will tell you where to look for your problem. While a breather can band-aid an issue. The real question what causing the problem to begin with.
The most effective way of pulling crank case pressure is using a vacuum pump and NOT recycling it into the intake stream. The oil will burn and will cause knock.
While the factory PCV does okay at best on a stock engine. It does a poor job once the cubic inches/piston speed increases, blow by from low tension or larger gapped rings and power adders. The factory has installed a PCV system due to emissions first and foremost and it does decrease crank case pressure to some degree. So it was a win win for the OEM.
Now ask your self why your PCV system is pushing oil. It is because the system isn't adequate and there is an airflow restriction. This is where breathers or a vacuum pump comes into play.
Now lets talk about this unmetered air you reference when running a breather. The engine will pull air from the path of least resistance. If it happens to be either through the PCV or the breather, it does not matter! It is all unmetered! I have tuned my fair share of LS vehicles and I have yet to see any noticeable changes in fueling error just by adding a breather.
Things can be simple and work... KISS- Keep It Simple Stupid. In all different motor sports from 2 stroke to 4 they run breathers... Why? Because it is simple and it works.
James like we talked about on the phone... Compression and leak down test. This will tell you where to look for your problem. While a breather can band-aid an issue. The real question what causing the problem to begin with.
04-09-2012, 04:16 PM
#67
yeah i gotcah I just dont know when I can get it in to get a leakdown and compression test right now shes my daily driver, all in all it dont seem to be doing to bad, I think since the breather is sitting at a 45 degree angle may be why oil is leaking out of it im sure its getting misted with oil and its just pooling and leaking out not actually blowing out.
I emptied the catchcan and with about 1500[1700 miles on it it had about a teaspoon to tablespoon of oil in it. I also switched the lines from the catchan to how they look in the other posters picture, mine were reversed from that. I think I need a 45 degree neck on that breather and see what happens there, I did notice that there is some blackening on the exhaust tips and it might be suckin some oil threw the intake as well. we will see what these changes doo, I may add another breather just for measure. Josh I still plan to have you take a look at my tune and some other stuff on my car when I can actually afford to have some down time on it, right now I cant and I am going on leave next week also and will be driving it. since the breather though it hasnt pushed oil out anywhere else so maybe this is just something simple and nothing major. but I am still going to do a leakdown and compression test since this engine has never had one while in my posession
I emptied the catchcan and with about 1500[1700 miles on it it had about a teaspoon to tablespoon of oil in it. I also switched the lines from the catchan to how they look in the other posters picture, mine were reversed from that. I think I need a 45 degree neck on that breather and see what happens there, I did notice that there is some blackening on the exhaust tips and it might be suckin some oil threw the intake as well. we will see what these changes doo, I may add another breather just for measure. Josh I still plan to have you take a look at my tune and some other stuff on my car when I can actually afford to have some down time on it, right now I cant and I am going on leave next week also and will be driving it. since the breather though it hasnt pushed oil out anywhere else so maybe this is just something simple and nothing major. but I am still going to do a leakdown and compression test since this engine has never had one while in my posession
04-21-2012, 01:04 PM
#71
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ok i got a 418 ls3, and when you get on it and get the rpms high this thing builds up so much crankcase pressure it was blowing the oil dipstick out and shooting oil every where, we added a catch can and zip died the dipstick down and everything seemed fine until one time I got on it and saw all kinds of smoke out the back, got the car on a lift and looked like it blew oil out the back of the main seal (i dont think it damaged it) so then we added a breather, things seem to be ok from there but then after about 500 miles of strait driving I noticed that oil was leaking out of the breather.
What is going on with this thing, i figure a catchcan and breather would stop excess crankcase pressure from doing this,
I really need help here i dont want my car shooting oil everywhere when I get on it.
What is going on with this thing, i figure a catchcan and breather would stop excess crankcase pressure from doing this,
I really need help here i dont want my car shooting oil everywhere when I get on it.
Thanks
04-21-2012, 10:10 PM
#72
stock logbock ls2,33k miles,carb. car has been running for weeks and i just hooked up a breather/catch combo today. no oil anywhere before it was installed, both valvecover tubes were wide open, no hoses,breathers,or pcv.
both hoses go into an aluminum catch can (one into each side) with a breather on top. done and done.
those diagrams someone posted in a link are the most rube goldberg crap ive ever seen. does it make your coffee too?
both hoses go into an aluminum catch can (one into each side) with a breather on top. done and done.
those diagrams someone posted in a link are the most rube goldberg crap ive ever seen. does it make your coffee too?
04-22-2012, 11:39 AM
#73
im just going to run a breather on each valve covor on the tubes and put the oil cap back on I dont think I am really blowing oil I think its just the fact thers no oil cap and its covering up the breather on oil then leaking out, cause it dont start leaking until its been running a while
04-23-2012, 05:00 PM
#75
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Just bought one of these on ebay to go with my oil catch can, hope it works w/o having to do leak down test or buy a vacuum pump $$. Stay tuned.
Thanks 1N_Only for sharing your expertise on PM
http://www.ebay.com/itm/290689914020...9#ht_593wt_700
Thanks 1N_Only for sharing your expertise on PM
http://www.ebay.com/itm/290689914020...9#ht_593wt_700
04-23-2012, 08:50 PM
#77
http://www.jdpmotorsports.com/rx-per...-ss-rx-camss-b
I ordered this because it only vents out and it has a valve that won't let unmetered air in just out. So we'll shall see lol
I ordered this because it only vents out and it has a valve that won't let unmetered air in just out. So we'll shall see lol
04-24-2012, 04:34 PM
#78
Ok guys let me help you out. Running breathers or not breathers only does one thing. It allows the engine to breath out the breathers instead of the dipstick,seals,or gaskets etc. There is nothing wrong with having breathers and all engines must have some sort of them. Some systems that breath are called pcv systems. Personally I like a pcv system as I want filtered air going throught the crankcase on cruise and I don't want to smell the venting oil on WOT. The proper way for it to be setup is to make sure that the vents coming to your catch can or oil seperator are baffled which they are on the pass side v/c. The lifter valley line should enter the bottom of the catchcan/seperator. The v/c line ahould enter about half way up the catch can. The pcv line should come out of the top of the can and go to manifold vacum. Now on the drivers side v/c You should have a line that is larger (#10-12) that is either baffled in the v/c or uses an external baffle like an after market breather that has a hose barb not a breather on it. That line should go the the throttle body between the filter and the throttle plate.
At cruise you have manifold vacum that pulls crankcase vapors through the engine crossways using filtered air that comes from the line on the driver v/c. At med throttle the engine is allowed to vent into both the pcv system and out the drivers v/c which then burns it in the engine. At WOTthe pcv valve closes and the system vents all the gases out the driver side v/c to be burnt in the engine. You should not have enough blow by for the short periods of WOT to actually pump a large amount of oil into the engine. If you do you have engine issues. Once you return to cruise the system reverses and cleans all the vapors back through the enigne and pcv system. Once you shut the vehicle off the oil from the catch can drains back into the engine. We have run theis system on good engines at WOT for periods of up to one hour without issues.
At cruise you have manifold vacum that pulls crankcase vapors through the engine crossways using filtered air that comes from the line on the driver v/c. At med throttle the engine is allowed to vent into both the pcv system and out the drivers v/c which then burns it in the engine. At WOTthe pcv valve closes and the system vents all the gases out the driver side v/c to be burnt in the engine. You should not have enough blow by for the short periods of WOT to actually pump a large amount of oil into the engine. If you do you have engine issues. Once you return to cruise the system reverses and cleans all the vapors back through the enigne and pcv system. Once you shut the vehicle off the oil from the catch can drains back into the engine. We have run theis system on good engines at WOT for periods of up to one hour without issues.
04-24-2012, 05:32 PM
#79
Breathers are a band-aid, you need to address the true issues. I have tried and removed breathers on LS1 and LS3 motors. they all leak oil. You need to get a properly set up PCV system and find out why you have excessive pressure in the crankcase, and fix it. It is not normal, and any good builder will tell you that. Also NEVER do any autox/ RR with breathers. the sustained cornering and high RPM fill the upper motor with oil that then FLOWS out the breathers a onto hot parts. Most competent tech will bounce you for having a breather on a LS motor
04-24-2012, 07:18 PM
#80
Breathers are a band-aid, you need to address the true issues. I have tried and removed breathers on LS1 and LS3 motors. they all leak oil. You need to get a properly set up PCV system and find out why you have excessive pressure in the crankcase, and fix it. It is not normal, and any good builder will tell you that. Also NEVER do any autox/ RR with breathers. the sustained cornering and high RPM fill the upper motor with oil that then FLOWS out the breathers a onto hot parts. Most competent tech will bounce you for having a breather on a LS motor