CCV issues, why is there positive pressure??
Senior Member
Joined: Jan 2012
Posts: 952
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Year: 2004
Model: Grand Cherokee
Engine: 2000 4.0
Absolutely not!!! I do not how old you are but I remember well in the days before CCV and PCV the inside of engines past 60000 miles were sludge nightmares.
And those cars had a draft tube hanging below the chassis to create some negative pressure.
The CCV also improves gas mileage.
And those cars had a draft tube hanging below the chassis to create some negative pressure.
The CCV also improves gas mileage.
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Joined: Aug 2011
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From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
CF Veteran
Joined: May 2012
Posts: 7,965
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From: Lost in the wilds of Virginia
Year: 1998 Classic (I'll get it running soon....) and 02 Grand
Model: Cherokee (XJ)
Engine: 4.0
Try it some time. Extreme conditions do strange things.
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
Vacuum vents the Crankcase when there is little blowby.
Listen to the man. I've seen valve covers with only room for the rockers to move. Yea, I was only 12 years old. Wanna guess which job I got?
No whining. 
And...don't forget anytime the air in there cools and contracts, the C-case "inhales" air at some humidity.
I'd just hook it all up the way it is suppose to go, install a 195* Mopar thermostat, maybe do Cruisers valve cover mod, then run it and see if there is any issue.
If there were some nutty amount of water you could rout the line through a small tank between the VC and the air box.
Listen to the man. I've seen valve covers with only room for the rockers to move. Yea, I was only 12 years old. Wanna guess which job I got? No whining. And...don't forget anytime the air in there cools and contracts, the C-case "inhales" air at some humidity.
I'd just hook it all up the way it is suppose to go, install a 195* Mopar thermostat, maybe do Cruisers valve cover mod, then run it and see if there is any issue.
If there were some nutty amount of water you could rout the line through a small tank between the VC and the air box.
CF Veteran
Joined: Feb 2013
Posts: 1,802
Likes: 2
From: Justin, TEXAS
Year: 1988
Model: Cherokee
Engine: 4.0
Well I had a weird problem a while back that cruiser helped me fix.
(this is with all brand new CCV equipment)
If I had both breathers where there supposed to be(airbox for front and intake manifold for rear) the front breather was always clean. But the rear was sucking in almost 1 qt of oil in the intake manifold every 200miles!
When I unplug the rear breather that's when oil came out the front into the air cleaner!
So I did cruisers valve cover mod and that stopped 99% of the oil coming through the rear breather and the front was always clean unless the rear was not in working order or unplugged.
Ponder on that one, I still haven't figured out why it did that
(this is with all brand new CCV equipment)
If I had both breathers where there supposed to be(airbox for front and intake manifold for rear) the front breather was always clean. But the rear was sucking in almost 1 qt of oil in the intake manifold every 200miles!
When I unplug the rear breather that's when oil came out the front into the air cleaner!
So I did cruisers valve cover mod and that stopped 99% of the oil coming through the rear breather and the front was always clean unless the rear was not in working order or unplugged.
Ponder on that one, I still haven't figured out why it did that
CF Veteran
Joined: Feb 2013
Posts: 1,802
Likes: 2
From: Justin, TEXAS
Year: 1988
Model: Cherokee
Engine: 4.0
Vacuum vents the Crankcase when there is little blowby.
Listen to the man. I've seen valve covers with only room for the rockers to move. Yea, I was only 12 years old. Wanna guess which job I got?
No whining.
And...don't forget anytime the air in there cools and contracts, the C-case "inhales" air at some humidity.
I'd just hook it all up the way it is suppose to go, install a 195* Mopar thermostat, maybe do Cruisers valve cover mod, then run it and see if there is any issue.
If there were some nutty amount of water you could rout the line through a small tank between the VC and the air box.
Listen to the man. I've seen valve covers with only room for the rockers to move. Yea, I was only 12 years old. Wanna guess which job I got? No whining. And...don't forget anytime the air in there cools and contracts, the C-case "inhales" air at some humidity.
I'd just hook it all up the way it is suppose to go, install a 195* Mopar thermostat, maybe do Cruisers valve cover mod, then run it and see if there is any issue.
If there were some nutty amount of water you could rout the line through a small tank between the VC and the air box.
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
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