- Location
- Port Orchard, WA
wildman said:
Got FSM?
-
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Air filter, oil blowback?
- Thread starter wildman
- Start date
Got FSM?
wildman
NAXJA Forum User
- Location
- Jennings, LA
XJ_ranger said:
actually yes
wildman
NAXJA Forum User
- Location
- Jennings, LA
XJ_ranger said:
actually yes, if you mean factory service manual...or did you mean flying spaghetti men?
Gil BullyKatz
NAXJA Forum User
- Location
- 2003UB313 Planet ERIS
After MULTIPLE
tubing replacements...
valve cover cleanings...
different oil combinations...
I've realized there are 2 ways to deal with blowby:
Catch can or rebuild
p.s. Check to make sure the inlet on the intake manifold is not clogged, it's the one towards the rear of it.
tubing replacements...
valve cover cleanings...
different oil combinations...
I've realized there are 2 ways to deal with blowby:
Catch can or rebuild
p.s. Check to make sure the inlet on the intake manifold is not clogged, it's the one towards the rear of it.
LazarusMJ
NAXJA Forum User
- Location
- New Hampshire
old_man said:
Read the original post old man. If OIL were getting past the rings it would go out the exhaust. No where did anyone say anything about cylinder pressure getting past the rings. Just because you know some shit doesn't mean you know everything. If you had paid attention to the posts you would have realized that in the context of this discussion I am NOT WRONG.
- Location
- NC Sandhills
Not the most treading lightly method out there, but a couple pieces of PVC pipe and elbows... vent that crud over the passenger side of the valve cover and down/out into the jet stream. Keeps the undercarriage from rusting
Actually I did spend the $120 or so at the dealer for the front & rear CCV harness & pipes, since my vintage 1988 junk was rough looking & brittle... with a K&N cone filter, the oil just seeks out the low point, oozes through, and ends up in approx the same place as the first quick/cheap method referenced above... it just travels first-class vs coach to get there
:dunno: got fresh engine?
Actually I did spend the $120 or so at the dealer for the front & rear CCV harness & pipes, since my vintage 1988 junk was rough looking & brittle... with a K&N cone filter, the oil just seeks out the low point, oozes through, and ends up in approx the same place as the first quick/cheap method referenced above... it just travels first-class vs coach to get there
:dunno: got fresh engine?
old_man
NAXJA Forum User
- Location
- Loveland, Colorado
This is where you are wrong.
The piston rings keep the pressure in the cylinder. If the pressure blows by the rings, it puts pressure in crank case that is open to the valve cover and forces the oil up and out the breather and into the air cleaner. If there is no leakage past the rings, there is no need for a breather.
I understand that oil can get past the oil ring and then burn in the cylinder and be pumped out the exhaust with the rest of the gasses, but this guy is talking about oil being blown out the valve cover. That oil isn't under pressure to get past the oil ring, it is a film on the cylinder wall that is not scraped off by the oil ring.
The reason I harp on the details is that there are tons of people who read these posts. Many are learning about engines for the first time. They take what they read on here pretty much as gospel. You need to be very clear and very specific.
The piston rings keep the pressure in the cylinder. If the pressure blows by the rings, it puts pressure in crank case that is open to the valve cover and forces the oil up and out the breather and into the air cleaner. If there is no leakage past the rings, there is no need for a breather.
I understand that oil can get past the oil ring and then burn in the cylinder and be pumped out the exhaust with the rest of the gasses, but this guy is talking about oil being blown out the valve cover. That oil isn't under pressure to get past the oil ring, it is a film on the cylinder wall that is not scraped off by the oil ring.
The reason I harp on the details is that there are tons of people who read these posts. Many are learning about engines for the first time. They take what they read on here pretty much as gospel. You need to be very clear and very specific.
Some people get really offended in here ,..huh?
Well like Old_Man said, it IS a misunderstanding. You both are correct. Oil passing the rings does create pressure in the Valve Train, and its thereby released Via the Crankcase Ventilation System, whether it be PCV or CCV it acts the same way, and creates the same results.
On the other hand, oil does move from the Combustion chamber via the Exhaust, therefore when you have a worn engine, you usually have excessive Blow-by and that PRETTY black smoke....
Well like Old_Man said, it IS a misunderstanding. You both are correct. Oil passing the rings does create pressure in the Valve Train, and its thereby released Via the Crankcase Ventilation System, whether it be PCV or CCV it acts the same way, and creates the same results.
On the other hand, oil does move from the Combustion chamber via the Exhaust, therefore when you have a worn engine, you usually have excessive Blow-by and that PRETTY black smoke....
George2
NAXJA Forum User
- Location
- New Hampshire
Ding. Old Man: 1, Others: 0.
Invest in a valve cover gasket, and go tearing into it. Clean up the junk that has accumulated in the CCV orifice plate (which is factory spec'd at 3mm), and then maybe drill that sucker out to 1/4". Even NEW 4.0's had "blowby" issues, which is why there are so many dealer notices about the subject.
Put everything back together, and try running some "soft" lines instead of the hard plastic lines that get plugged up easily. The intake vaccuum will be plenty enough to draw from the new "resized" orifice plate, and your filter will be dry and happy forevermore. Blowby is a natural 4.0 engine occourance, and there's tons of "workarounds" on the Forums- the "search" function taught me more than I wanted to know- but I have a neat and clean K&N filter to show for it!
Change the soft lines yearly (or as they get "soggy"). One sign that things have gotten out of hand is oil in the distributor, which is really the most extreme situation. My first "sign" was when my dipstick (with really tight oil seal) blew off on the highway- which was followed by a beautiful cloud of blue smoke as the oil pumped out of the dipstick tube under pressure. Needless to say, things under my Jeep are nice and lubed!
Check out a turbo-ed 4.0 at JP magazine, and they show BOTH breathers having filters- and that's because the vaccuum of the motor performs a number of functions- and it's assumed that the engine is new, and pretty tight. Also, the intake is under a boost, so air would be flowing INTO the valve cover, which is not good.
http://jpmagazine.com/techarticles/engine/154_0508_turb/
The front port should draw air FROM your filter, no matter what kind it is. There should ALWAYS be a vaccuum FROM it, when the motor is running. The rear port should always be ATTACHED to a vacuum, like from a port on your intake manifold. Once you pull that line, then everything under the valve cover is under engine pressure. If both lines were pulled, then you should effectively feel a "poofing" as the crankcase pressure blows through both lines.
Back port to a good vaccuum, front port to a source of clean, filtered air.
Invest in a valve cover gasket, and go tearing into it. Clean up the junk that has accumulated in the CCV orifice plate (which is factory spec'd at 3mm), and then maybe drill that sucker out to 1/4". Even NEW 4.0's had "blowby" issues, which is why there are so many dealer notices about the subject.
Put everything back together, and try running some "soft" lines instead of the hard plastic lines that get plugged up easily. The intake vaccuum will be plenty enough to draw from the new "resized" orifice plate, and your filter will be dry and happy forevermore. Blowby is a natural 4.0 engine occourance, and there's tons of "workarounds" on the Forums- the "search" function taught me more than I wanted to know- but I have a neat and clean K&N filter to show for it!
Change the soft lines yearly (or as they get "soggy"). One sign that things have gotten out of hand is oil in the distributor, which is really the most extreme situation. My first "sign" was when my dipstick (with really tight oil seal) blew off on the highway- which was followed by a beautiful cloud of blue smoke as the oil pumped out of the dipstick tube under pressure. Needless to say, things under my Jeep are nice and lubed!
Check out a turbo-ed 4.0 at JP magazine, and they show BOTH breathers having filters- and that's because the vaccuum of the motor performs a number of functions- and it's assumed that the engine is new, and pretty tight. Also, the intake is under a boost, so air would be flowing INTO the valve cover, which is not good.
http://jpmagazine.com/techarticles/engine/154_0508_turb/
The front port should draw air FROM your filter, no matter what kind it is. There should ALWAYS be a vaccuum FROM it, when the motor is running. The rear port should always be ATTACHED to a vacuum, like from a port on your intake manifold. Once you pull that line, then everything under the valve cover is under engine pressure. If both lines were pulled, then you should effectively feel a "poofing" as the crankcase pressure blows through both lines.
Back port to a good vaccuum, front port to a source of clean, filtered air.
wildman
NAXJA Forum User
- Location
- Jennings, LA
George2 said:
So runnin a filter up front, like I used to do, and like they do on the turbo'ed motor u sent a link to, is a good idea then?
Well, on the turbo'ed, they have a filter in the rear too...but u say port it to a good vacuum. What kind of difference would that make? I'm just going to disconnect the lines to the rear and clean them out and reconnect probably.
George2
NAXJA Forum User
- Location
- New Hampshire
You COULD run one of those little filters up front, but I see no value there, since you already have one that's designed into the works- The intake manifold is the SOURCE of your vaccuum, which pulls fumes from your valve cover, FROM the filtered air from your air filter. BOTH are under vaccuum, but the potential changes as the orifice plate gets plugged up.
The REAR line is the key to the whole setup, and becomes the weak link when the orifice plate gets plugged up. I've had friends pull the orifice plate, but they suck heavy oil fumes into the intake, and it's pretty bad on cold mornings when the engine is first warming up. There HAS to be some sort of restriction, and the plate is hidden within some baffles- so it's not exposed to direct oil splash.
If the plate gets plugged, then you only have the front line working, and that's under intake vaccuum- which draws oil and oil-laden fumes from under the valve cover. What WAS a line that's supposed to be under vaccuum, is now under pressure from the engine blowby gasses, which are sopped with oil.
I'd recommend pulling the valve cover, and cleaning things up inside there first.
Check the little round plate, and maybe open up the orifice a little, to get a good vaccuum pull from the intake manifold. I had to run 3/8" fuel line tubing to get a healthy pull out of the valve cover, and now my intake manifold pull is way stronger than the natural pressure under the valve cover- I can take the front line off of the air filter, and get a good suction from it. Maybe it makes more sense if I said it draws from front to back? It sucks from the air box, through the valve cover, then into the intake manifold. If the manifold vaccuum gets plugged, then the airbox vaccuum becomes the "pull", and that's where all the fumes and oil will go.
Without more suction, then all of your under valvecover pressure will head to the source of least resistance, which is back into your intake and air filter box. Think of the whole thing as a "2nd intake", and it's a little easier to sort out.
The REAR line is the key to the whole setup, and becomes the weak link when the orifice plate gets plugged up. I've had friends pull the orifice plate, but they suck heavy oil fumes into the intake, and it's pretty bad on cold mornings when the engine is first warming up. There HAS to be some sort of restriction, and the plate is hidden within some baffles- so it's not exposed to direct oil splash.
If the plate gets plugged, then you only have the front line working, and that's under intake vaccuum- which draws oil and oil-laden fumes from under the valve cover. What WAS a line that's supposed to be under vaccuum, is now under pressure from the engine blowby gasses, which are sopped with oil.
I'd recommend pulling the valve cover, and cleaning things up inside there first.
Check the little round plate, and maybe open up the orifice a little, to get a good vaccuum pull from the intake manifold. I had to run 3/8" fuel line tubing to get a healthy pull out of the valve cover, and now my intake manifold pull is way stronger than the natural pressure under the valve cover- I can take the front line off of the air filter, and get a good suction from it. Maybe it makes more sense if I said it draws from front to back? It sucks from the air box, through the valve cover, then into the intake manifold. If the manifold vaccuum gets plugged, then the airbox vaccuum becomes the "pull", and that's where all the fumes and oil will go.
Without more suction, then all of your under valvecover pressure will head to the source of least resistance, which is back into your intake and air filter box. Think of the whole thing as a "2nd intake", and it's a little easier to sort out.
livewire
NAXJA Forum User
- Location
- Burbank CA
You can order the emission hose kits from kragen auto parts. I ordered them yesterday. They were in Dorman-dorman catalogue. The part numbers were 46003 and 46004. These are all the hoses that plug together on top of the intake manifold. 46003 is the half that goes to the valve cover. 46004 is the half that goes to the air filter box. They were $29.99 each. Thats in california. Said they would have them in 4 days.
Hope This Helps Livewire
Hope This Helps Livewire
livewire
NAXJA Forum User
- Location
- Burbank CA
Here is a link to 46004 http://www.partsamerica.com/ProductDetail.aspx?mfrcode=RNB&mfrpartnumber=46004
livewire
NAXJA Forum User
- Location
- Burbank CA
here is a link to 46003 http://www.partsamerica.com/ProductDetail.aspx?mfrcode=RNB&mfrpartnumber=46003
livewire
NAXJA Forum User
- Location
- Burbank CA
If the link is not working You may have to turn off cookies. Thats what I had to do.
TekkaMaki
NAXJA Member #672
- Location
- Framingham, MA
Cherokee America has two good articles I found really helpfull on fixing blow-by with part numbers for the CCV lines and grommets from the dealer etc.
old_man
NAXJA Forum User
- Location
- Loveland, Colorado
Kat, that was using your head.
