Catch can full?

merkyworks

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This is my current setup. UPR catch cans with check valves on green and yellow lines to prevent blow back into valve cover. CFM oil cap breather, under vacuum check valve is closed and doesn't allow air in but when crank case develops positive pressure the check valve opens and allows the positive pressure to vent.

I've had good results with this setup.
-PCV is still in tact allowing a vacuum to be pulled on the crank case during normal driving (which is good)
-Long hose routing and double catch cans gives time for oil to drop out of the air
-Double check valves on PCV lines ensure no positive pressure makes it way back to the valve cover/crank case
-Any positive crank case pressure is vented by oil cap breather

Annotation 2019-09-17 132601.png
 

70SCJ

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This is my current setup. UPR catch cans with check valves on green and yellow lines to prevent blow back into valve cover. CFM oil cap breather, under vacuum check valve is closed and doesn't allow air in but when crank case develops positive pressure the check valve opens and allows the positive pressure to vent.

I've had good results with this setup.
-PCV is still in tact allowing a vacuum to be pulled on the crank case during normal driving (which is good)
-Long hose routing and double catch cans gives time for oil to drop out of the air
-Double check valves on PCV lines ensure no positive pressure makes it way back to the valve cover/crank case
-Any positive crank case pressure is vented by oil cap breather

View attachment 1599525
I like that setup. As soon as I can figure out why I seem to have positive pressure venting at idle I would like to put something like that setup.
 

fullboogie

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I really don't understand how you're venting that much pressure. You should have a massive vacuum leak when you remove that hose - to the point that the engine stalls. Really having trouble envisioning how you have positive pressure in that system. Can you take a pic of the hose you are getting pressure out of?
 

70SCJ

(Ret) USMC F/A-18 Driver
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I really don't understand how you're venting that much pressure. You should have a massive vacuum leak when you remove that hose - to the point that the engine stalls. Really having trouble envisioning how you have positive pressure in that system. Can you take a pic of the hose you are getting pressure out of?
I’ll re-check it and get a pic.
I think the engine would have stalled. The hose was only unplugged for a second or 2.
 

70SCJ

(Ret) USMC F/A-18 Driver
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I really don't understand how you're venting that much pressure. You should have a massive vacuum leak when you remove that hose - to the point that the engine stalls. Really having trouble envisioning how you have positive pressure in that system. Can you take a pic of the hose you are getting pressure out of?
I re-checked my findings and found that I completely misinterpreted what the hissing noise was when I unplugged the hose off of the pcv valve. The hissing was from the hose leading to the SC. It was sucking a lot of air. No air that I could tell was exiting the pvc.
Sorry for sending everyone down a dry hole.
 
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70SCJ

(Ret) USMC F/A-18 Driver
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Really having trouble envisioning how you have positive pressure in that system. Can you take a pic of the hose you are getting pressure out of?
Here is the pic of the valve and where I unplugged the hose. Again I figured out the suction noise was from the SC side the hose.
 

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fullboogie

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Good lesson for getting things right before asking for help. This thread is 3 weeks old and we're just now finding out the PCV is working perfectly.
 

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