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About deleting PCV in 6.5TD

I understand that the spring is progressive as you could describe as modulated, and not on/off, but I believe at some point there is a full on and a full off with varying amounts of on.
 
I found that with the Oil seperator on my 98 that at idle there is positive pressure in the crankcase,it works fine at higher RPM's tho.
Looks like these things are mainly designed for stationairy engines that run at high idle or WOT.
High blowby overwelms these things too.+ you got another filter to replace periodically.
IMO it's not worth the cost and trouble installing one of these things on our trucks.
 
Think of it as the opposite of a nitrogen or air pressure regulator. If you have a high pressure side that was between 90 psi to 2000 psi. The outlet pressure was set to 25 psi. The regulator would be varied amounts of lets say 90% to 99.971242% closed based on how much flow was required to maintain the 25 psi outlet pressure. It will still give you 25 psi, but it will vary the amount of the opening to maintain that pressure. It may me a mouse hair open, but she's still open enough to maintain that setting. Closed would be at pressure (25 psi) with NO FLOW. It would open more to maintain that pressure at a higher flow rate... but, kinda doubtful in our running engines we'd ever arrive at a no blowby condition and the CDR fully closed.
 
I think the biggest problem the CDR has is we've changed the design parameter by increasing boost(most of us anyways)
 
Its not that we dont understand how the CDR works, its just that I dont believe its as "regulated" as you make it out to be. You may have a reverse understanding of the CDR, it doesnt operate as a PCV valve. It is fully open at idle when there is no vacuum. vacuum from higher RPMs and turbo pulls it closed, to make the restirction greater to limit vacuum to the crankcase.

The more vacuum in the intake elbow the more the diaphragm closes, I think its that simple, and at some point you reach enough vacuum that its completely shut off with no flow. Try taking one and sucking air through it, see if you get to a point that it doesnt flow, thats one way to test if the diaphragm and spring are working. I guess I should have held it closed by keeping my finger over the air relief for the diaphragn so it couldn't expand to open again and try blowing through the other end to see if it could still push some through.
 
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the reason it won't be totally closed very often is even with high vacuum from the turbo your still creating crankcase pressure
 
Whatever the outcome folks,its a given fact that at low boost ,say 0 to 5-6 lbs at 1500 to 2000 RPM which is 90% of the time normal driving that CDR never blinks an eye.
So whatever oil there is suspended in the blow by whether you got a little or a lot is straight going in the intake,bye bye oil.

The emision control freaks never cared for that one.
 
bison said:
Whatever the outcome folks,its a given fact that at low boost ,say 0 to 5-6 lbs at 1500 to 2000 RPM which is 90% of the time normal driving that CDR never blinks an eye.
So whatever oil there is suspended in the blow by whether you got a little or a lot is straight going in the intake,bye bye oil.

The emision control freaks never cared for that one.
Click to expand...

Very true, I really would like to put one of those provents on, it makes sense.

Wasnt there a picture of the internals somewhere on this site, I was thinking that when the diaphragm closes shut it closed off the flow in a perpendicular way and not in a manner that pressure would push it open, like its not a push pull relationship, since both forces are in the same direction.
 
buddy said:
Very true, I really would like to put one of those provents on, it makes sense.Wasnt there a picture of the internals somewhere on this site, I was thinking that when the diaphragm closes shut it closed off the flow in a perpendicular way and not in a manner that pressure would push it open, like its not a push pull relationship, since both forces are in the same direction.
Click to expand...

In my experience.It builds positive crankcase pressure at idle.
 
Holy cow batman,that's quite a pipeline you laid there!
IMO that run is way to long and will prob collect oil in the dips of the hose over time, plugging it off.
BTW,what is that black hose upfront in the pic for?
 
Yes, explain whats going on there. The T's are for the heater hose right? But what goes up towards the front?

You just venting the valve cover to the drivers side?
 
Where should it be leaded? Or just put breather filter after that metal pipe from valve cover?
I haven´t touched those hoses, I thought they are original!? :WTF:
I cant´t remember, but I think it goes to radiator :???: I can check that, but they were not like that when car left the factory???
 
Thats just the extra stuff you have for it being a suburban with rear heater. I have not seen them like that, the truck returns come between the wheel well and the turbo. It just looks convoluted in the picture, and all you really did was vent it to the drivers side. For what its worth, I would make the vent tube as short as possible, just dump down on passenger side, because hose length will add backpressure that will maintain more crankcase pressure. The CDR itself makes for a convenient 90 degree elbow, since it should be full open with no vacuum on it. Or any elbow that fits in there.
 
Ama83 said:
Where should it be leaded? Or just put breather filter after that metal pipe from valve cover?
I haven´t touched those hoses, I thought they are original!? :WTF:
I cant´t remember, but I think it goes to radiator :???: I can check that, but they were not like that when car left the factory???
Click to expand...
I would leave the CDR and metal tube in place,hook an elbow to the tube and hose straight down in front of the turbo.

Did i just repeat myself here?:(
 
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