6.5L
Old Iron Runner
So I know from the factory the CDR routes back into the intake. Do you have to route it back into the intake pre-turbo or can you just vent to atmosphere? Any cons to venting to atmosphere?
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CDR routing options
- Thread starter 6.5L
- Start date
Olddieselguy
Member
I have often wondered about the CDR valve. One day i was doing a service on my truck. I pulled out the air filter to change it. Well the phone rang, a friend stopped by then the phone again. To make a long story short i slammed the hood and forgot to install the air filter. Ran into town and back and ever since that day the rear main has leaked a ton of oil. Air filter was horribly dirty and it ran great w/o the filter installed. My guess to why the leak started is the CDR allowed my engine to over pressurize due to a lack of air restriction, higher turbo pressure and then blow the rear main.
My truck has a rope seal rear main its a 6.2L with 6.5L DS4 pump and turbo.
I know for emissions reasons its probably best that the oil vapors get burned, but some engines like Cummins and Duramaxes vent out the atmosphere. So it probably doesn't matter too much.
My truck has a rope seal rear main its a 6.2L with 6.5L DS4 pump and turbo.
I know for emissions reasons its probably best that the oil vapors get burned, but some engines like Cummins and Duramaxes vent out the atmosphere. So it probably doesn't matter too much.
Will L.
Well-Known Member
CDR Crankcase Depression Regulator
Olddieselguy : good diagnosis.
6.5: there are some lengthy threads here if you do a search about it. A worth while read to learn how to clean and test.
As long as your seals are good and you don't have a lot of blowby the best thing is to keep it stock. Once blowby is bad enough to cause you to burn a lot of oil you might consider venting to atmosphere (oil seals will usually leak by then anyways) if legal in your area, or add a catch can (cant remember proper term) to return the oil to the pan instead of burning it.
Olddieselguy : good diagnosis.
6.5: there are some lengthy threads here if you do a search about it. A worth while read to learn how to clean and test.
As long as your seals are good and you don't have a lot of blowby the best thing is to keep it stock. Once blowby is bad enough to cause you to burn a lot of oil you might consider venting to atmosphere (oil seals will usually leak by then anyways) if legal in your area, or add a catch can (cant remember proper term) to return the oil to the pan instead of burning it.
6.5L
Old Iron Runner
So is there somewhere I can vent to other than into the intake that won't cause any problems?
JMJNet
Recruit
The turbo creates a slightly higher pressure to suck in all those oil vapor and puts it back into the turbo oil return line.
My information may be wrong because you said it routes it back to the intake???
Part is not that expensive!!!
There are a lot of discussion on this topic, you can probably search it.
My information may be wrong because you said it routes it back to the intake???
Part is not that expensive!!!
There are a lot of discussion on this topic, you can probably search it.
6.5L
Old Iron Runner
I'm not talking about replacing it. I just want simple mounting options. Mine has always routed pre turbo into the intake. I though they all were. I there anywhere other than the intake where I can vent it to without it causing any issues at all??
:dr: Say what? The CDR puts a vacuum on the crankcase. So replacing a clogged air filter would reduce the constant vacuum on the crankcase. This elimination of crankcase vacuum will allow bad seals to leak more. The CDR is on the vacuum side of the turbo! It isn't pressurizing the crankcase from the turbo. A quick look at the plumbing going before the turbo should confirm this. if the crankcase is seeing turbo boost something is very wrong with the setup.
I have seen a rear main seal quit leaking on a 200K mile 4.3L gas engine after unclogging the PCV system in/under the TBI.
As far as venting a CDR to the road it is only a bad idea on high blow by engines that can fog an intersection. It really doesn't hurt anything to keep it in the intake on a non-EGR engine.
6.5L
Old Iron Runner
I'm not talking about the intake. right now, intake is out of the question. I want to confirm that I can to vent to atmosphere for a while until I can get some shit worked out without screwing anything up at all?
Yes, you can even take the tuna can out and run a plain old hose somewhere vented to atmosphere. Under the passenger side battery and let any oil drip into the tray. My only caution is any blowby will be coming out of that hose as a white smoke. The more blowby... The last truck I attempted this on smoked like it was on fire after getting off the freeway from the CDR as the engine was well done...
6.5L
Old Iron Runner
It isn't permanent. just temporary until I can rework my intake. Little to no blow-by. A lot is getting moved around. My piping showed up today so maybe I will have it done before school next week. Spent the last two days doing a Competition Fuel System on my buddies 7.3L Superduty so I haven't had time to do anything at all!!
pacificdrumma
Well-Known Member
Mine has been dumping into the atmosphere since I had my turbo replaced in March '12. No issues.
You can direct the hose into a catch can then loosly stuff a rag in around the hose. The rag helps keep the hose inplace and acts like a filter to keep so much oil from giving the underside a rust preventative coating.
Will, PROVENT?
Olddieselguy
Member
Thank you Will L.
Before you go calling anybody retarded think about it first WarWagon. In a perfect world A CDR might be a great thing but why is it that RIGHT after i got back and even a year after that trip i still leak oil. BTW my intake and CDR routing is all factory setup. And this is not a gas 4.3L, its a diesel with COMPRESSION IGNITION meaning that it has 400 PSI compression, not some wimpy 150 psi. Oh and on the 4.3's the TBI bolts loosen and the gasket shrinks causing a vacuum leak making the PCV work incorrectly.
I have driven this truck for 8 years and the day after i got in a hurry and all of a sudden it starts to leak. Diagnose that one mister smarty pants!
In fact i have never considered my engine to be worn out. Still has great power, starts great in the cold and only uses about a quart of oil every 1500 miles. Pretty good for a red 1982 6.2L engine that has never been overhauled. In the early 90's my older brother put on a banks turbo system on his 6.2 and right after the rear main started to leak. After pulling the oil pan off 4 different times to fix the rear main leak we took off the CDR valve and routed the crankcase gasses into the intake before the turbo. GUESS WHAT THE OIL LEAKS STOPPED!!!!
Since you are the diesel god do i need to have you fix my truck?
Will L.
Well-Known Member
Yes provent.
Umm, routing the intake before the turbo is how it should have been and when the cdr works right it is free flowing so it should have worked there. The addition of th turbo is going to increase crankcase pressure. You just have to get rid of it somehow
Umm, routing the intake before the turbo is how it should have been and when the cdr works right it is free flowing so it should have worked there. The addition of th turbo is going to increase crankcase pressure. You just have to get rid of it somehow
3500GMC
What T F, over
Ok.
All this venting going on, thought I'd share my vent. ($.02)
Keep the oil, lose the pressure is the goal. If one could improve the oil control, the OE setup isn't all bad.
A little vacuum on the crankcase won't hurt a thing. One could argue that it keep oil leaks away- but so does Ultra Black RTV.
What you DO NOT want is any kind of pressure in the crankcase. Pressure = leaks for sure. (and usually more blowby due to the unseating of the rings)
A free flowing vent that keeps your oil where it should be will suffice.
Personally, I do not want my engine breathing it's own trash.
.
.
All this venting going on, thought I'd share my vent. ($.02)
Keep the oil, lose the pressure is the goal. If one could improve the oil control, the OE setup isn't all bad.
A little vacuum on the crankcase won't hurt a thing. One could argue that it keep oil leaks away- but so does Ultra Black RTV.
What you DO NOT want is any kind of pressure in the crankcase. Pressure = leaks for sure. (and usually more blowby due to the unseating of the rings)
A free flowing vent that keeps your oil where it should be will suffice.
Personally, I do not want my engine breathing it's own trash.
.
.
NVW
Well-Known Member
Looks nice
ak diesel driver
6.5 driver
and you never did a write up on this because you thought no one would be interested?? lol
X3, yea thats dead sexy! tell us more.
Will L.
Well-Known Member
Installed pics, inside story! The works please
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