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CCV issues, why is there positive pressure??

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Old Dec 7, 2013 | 08:39 PM
  #16  
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Originally Posted by skife
It doesn't need to be sucked out. It's just fine vented into the atmosphere.
ccv is not the same as pcv.
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Old Dec 7, 2013 | 08:58 PM
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Originally Posted by hankthetank
ccv is not the same as pcv.
well then, what's the difference?
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Old Dec 7, 2013 | 09:56 PM
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Originally Posted by 89CherokeeLee
What is your thought on a small breather filter right off the elbow?
When that plugs up inside where you can't see it, crank-case pressure will make it try to blow oil out everywhere. Rear main, ect. You might do an oil change and try that product, Restore. Their is a small chance than might help worn rings. Idk, maybe just''Snake oil". If you DO try it be sure to let us know!
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Old Dec 8, 2013 | 03:04 AM
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Originally Posted by skife
well then, what's the difference?
Pcv vavle has a check valve.
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Old Dec 8, 2013 | 09:33 AM
  #20  
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I used Restore with my last oil change, but I will probably be using it ever time. It is good stuff! Never hurts to baby the Jeep
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Old Dec 8, 2013 | 11:42 AM
  #21  
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Originally Posted by freegdr
Pcv vavle has a check valve.
So you could replace the ccv with a breather filter and be okay.
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Old Dec 8, 2013 | 11:48 AM
  #22  
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Originally Posted by skife
So you could replace the ccv with a breather filter and be okay.
No then there wont be vacuum suction at idle ccvs for idle other tubes for off idle ....people do it just not me and not a oil leak any where.
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Old Dec 8, 2013 | 09:24 PM
  #23  
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I've realized that the issue is not so much of the oil, it's also the fact that I just pulled off the new hose, and blew through it and straight water came out. A good amount of it. How could so much moisture be accumulating in the valve cover? Would that be my gasket?
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Old Dec 8, 2013 | 09:31 PM
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Depends on driving habit. If you only do short little trips water can build up and not completely evaporate as the engine doesn't stay at temp for a long time. Of course it could also be coolant lol
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Old Dec 8, 2013 | 10:11 PM
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The CCV valve has a 2.6mm orifice, an anti-backfire valve, and a function that closes it off under extreme vacuum. Idk what makes that Closed Crankcase Vent different than Positive Crankcase Ventilation besides maybe it closing off under high vacuum. (not even sure a PCV won't do that!)

Agreeing with Salad, venting any moisture is part of what it is for. With the right 195* t-stat running at temp for a while should vent normal moisture.

Last edited by DFlintstone; Dec 9, 2013 at 09:39 PM. Reason: not even sure
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Old Dec 8, 2013 | 10:21 PM
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Originally Posted by DFlintstone
Idk what makes that Closed Crankcase Vent different than Positive Crankcase Ventilation besides maybe it closing off under high vacuum. (noe even sure a PCV won't do that!)
I think it's supposed to just be "Crank Case Ventilation" to differentiate from "slobber tube", lol.

CCV systems in our engines have air constantly being drawn through them. PCV systems with a valve are normally shut and only release gasses when a certain pressure is hit. I imagine PCV system is inherently better as atmosphere isn't always flowing through it, reducing methods for contaminants to enter and condensation. Pretty sure any engine built in the last twenty years is all PCV jazz. However it sure is handy if you have a problem with the IAC!
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Old Dec 8, 2013 | 10:50 PM
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Originally Posted by 89CherokeeLee
I've realized that the issue is not so much of the oil, it's also the fact that I just pulled off the new hose, and blew through it and straight water came out. A good amount of it. How could so much moisture be accumulating in the valve cover? Would that be my gasket?
You just discovered why crankcase ventilation is necessary. No, venting to atmosphere is a bad idea so don't do it. When blow-by gets excessive in a badly worn engine the CCV or PCV gets overwhelmed. CCV & PCV systems both function in the same way. They create a negative pressure in the crank case to scavenge off blow-by. Where does the water come from? Simple, the byproduct of combustion is water.
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Old Dec 8, 2013 | 11:48 PM
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Originally Posted by salad
PCV systems with a valve are normally shut and only release gasses when a certain pressure is hit. I imagine PCV system is inherently better as atmosphere isn't always flowing through it,
I'm pretty sure a PVC sucks pretty much whenever there is manifold vacuum. That Positive Crankcase Ventilation was an improvement over a draft tube since "positive" ventilation cut down on sludge, moisture, and maybe acids building up. Some just had steel wool like stuff in the oil filler cap to filter any incoming air. Then it changed to a hose to the air cleaner.

How about "Continuous Crankcase Ventilation" for A CCV valve ?

Last edited by DFlintstone; Dec 8, 2013 at 11:55 PM.
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Old Dec 9, 2013 | 05:08 AM
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Originally Posted by DFlintstone
I'm pretty sure a PVC sucks pretty much whenever there is manifold vacuum. That Positive Crankcase Ventilation was an improvement over a draft tube since "positive" ventilation cut down on sludge, moisture, and maybe acids building up. Some just had steel wool like stuff in the oil filler cap to filter any incoming air. Then it changed to a hose to the air cleaner.

How about "Continuous Crankcase Ventilation" for A CCV valve ?
I have learned that CCV is Constant Crankcase Ventilation, yes. PCV is Positive Crancase Ventilation. The PCV check valve it to ensure the pressure stays positive while CCV is a continuous vacuum bringing air from the airbox into the crankcase, then into the intake manifold to burn the oil vapor... That't what I've been gathering anyway :P

The moisture seems to be coming from the crankcase, as the blowby condenses into the airbox. (which in theory should have negative pressure) So at least the moisture is making it into the filter rather than my engine.
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Old Dec 9, 2013 | 06:15 AM
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Originally Posted by 89CherokeeLee
So at least the moisture is making it into the filter rather than my engine.
Well, not really.

The moisture is STARTING in your engine. It starts in the cylinders and is blowing past the rings down into the guts, where all those nice bearings live, and your reservoir of oil. What fun! Water in your engine!


When you first start your engine, it's cold, and that steam (in the true sense of the word, the invisible stuff) gets cooled to water vapor and can condense on the interior of your engine, which causes it to accumulate in your oil, get in your bearings, etc. Some gets drawn out through the crankcase ventilation system.


When you run the engine hot enough and long enough, that nice big block of iron and all those other engine pieces and the air inside your engine get all heated up and keep the majority of the moisture in steam form, which then gets pulled out by the ventilation system and eventually goes into the atmosphere where it can't hurt your engine.

This is [part of] why it's very hard on an engine to do a lot of short trips, instead of long one.

You can see this in action at your exhaust pipe on a cool day. When the car is cool, you'll see plenty of water vapor coming out of the tailpipe. (Many people mistakenly call this "steam".)

Once the car warms up, you don't see it anymore. Why? The engine and exhaust system gets warmed up, and is no longer cooling the steam (which is invisible) to water vapor (which is visible). It hits the atmosphere as steam, and quickly dissipates before it can condense to water vapor.


Originally Posted by 89CherokeeLee
I just pulled off the new hose, and blew through it and straight water came out. A good amount of it.
If there's that much in the tubing, it's already all through your engine. You either have a coolant leak into your engine, or, more likely, you aren't getting your engine hot enough for long enough to get the blow-by moisture out of it.

That ain't good!
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