dieselviznince
Escanaba MICHIGAN
I tried to but can not find info on cdr where is it? If it is plugged it will cause excess oil usage? Will it make engine run like crap. Anyone know? Do I ask Agnem?
CDR info
- Thread starter dieselviznince
- Start date
I tried to but can not find info on cdr where is it? If it is plugged it will cause excess oil usage? Will it make engine run like crap. Anyone know? Do I ask Agnem?
icanfixall
Official GMM hand model
Usually its bolted to the back side of the intake opening. Its about the size of a tuna can.
Diesel JD
Full Access Member
Hmm, surprised no one answered but its really pretty simple. The CDR plugs into the valley pan grommet and feeds into the horn on your intake manifold. It reroutes blowby gases from the crankcase to the intake to be reburned. It is a matter of controversey here if a CDR can cause oil consumption, but Zigg and others have torn them down and suggest that they do not. Still, if it is actually plugged, you should repair or replace it. Pull it off, look for the little pinhole on the back of the valve. If it is gunked up it needs to be cleaned. Also if it has a lot of oil residue inside the valve it needs cleaning or replacement. If you want another, I have two here that I don't need or want, I would let you have them for the cost of shipping. Probably around 5-6 bucks.
dieselviznince
Escanaba MICHIGAN
Ok well I have to find the back of the engine part you speak of then I will let you know, what I find.
sle2115
NRA LIFE MEMBER
Take the air cleaner off, standing in front of the truck, looking at the motor, it is on the back side of the air intake (under the breather you just took off). If you look at the back of the intake throat, you can see a hole under the screen, it is the CDR entry point, look on the outside rear of the intake horn and you have found it. UNLESS you have a turbo, as many of them move it to another location.
Mr_Roboto
Full Access Member
The CDR does not plug closed, it sticks open which causes excessive crankcase gas flow at high RPM's. Which will suck in oil vapor and droplets, which otherwise would have re-condensed into liquid oil again.
illinoisboy
Full Access Member
so is this set up bad? is there a better option? sorry, new to the idi's. not sure if that is a good thing yet or not
Mr_Roboto
Full Access Member
Some folks prefer a road draft tube, particularly if their motor is very worn and has more blowby than the CDR can handle.
Since the CDR routes oil vapor to the intake, it tends to make the rear cylinders run hotter because the oil runs that direction.
Since the CDR routes oil vapor to the intake, it tends to make the rear cylinders run hotter because the oil runs that direction.
zigg
Full Access Member
The PURPOSE of the CDR is to prevent postive crankcase pressure due to combustion pressure leaking from the cylinders.(Crankcase depression regulator) Since it is connected to the intake, the oil droplets suspended in the blowby then are routed into the intake, and yes, they tend to run the rear 2 cylinders hotter as a result.
The fact the blowby has oil droplets in it, is A SYMPTOM OF ENGINE WEAR and has nothing to do with the CDR itself.
A road draft tube will eliminate oil going into the intake, but the fact remains, the oil is still there, and will be going into the atmosphere instead, but the amount leaving the engine will remain the same regardless.
The only way to prevent it would be to have some kind of condenser unit to catch the oil. Many have tried it, and since it seems to be only guys with worn engines, for the most part, it's been found to not make much difference, and the condenser units tend to elevate crankcase pressure, causing more oil leakage at all the usual spots.
Finally, if there is oil in the CDR, this is completely NORMAL. It will condense in there, and is supposed to, and then it drains back down into the valley pan. No amount of cleaning the unit or replacing it will have any effect whatsoever on the amount of oil that collects within the unit.
I've got a couple pics of one opened up, and you can see for y'self what's inside.
..Pic 1..
..pic 2..
(I tried to upload thumbs, but couldn't figger it out...)
Now I'll step down off my soapbox and zip up the flame suit....
Zigg
h2odrx
Anti-O
Zigg i say you are right on! 
I'm going to make an oil collector/condenser unit for my rig and see what happens. I'll post pictures and results. I'll do it for a month of driving so as to have a good record of it. stay tuned!!!
I'm going to make an oil collector/condenser unit for my rig and see what happens. I'll post pictures and results. I'll do it for a month of driving so as to have a good record of it. stay tuned!!!
JPR
Full Access Member
This is a commercial unit like your describing http://www.parker.com/racor/ccv_prod.html
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dieselviznince
Escanaba MICHIGAN
Well thats makes things easier for me to understand thanks everone.
Mr_Roboto
Full Access Member
It's a CDR VALVE. Saying that it just prevents crankcase pressure is over simplistic. You could do that with a simple fitting.
Diesels have almost no vacuum at idle, and the vacuum increases as airflow (RPM) increases. The CDR's job is similar to a PCV valve, which is to regulate the flow of crankcase gasses as vacuum levels vary. Without this, you would see many times more flow in high vacuum situations.
Diesels have almost no vacuum at idle, and the vacuum increases as airflow (RPM) increases. The CDR's job is similar to a PCV valve, which is to regulate the flow of crankcase gasses as vacuum levels vary. Without this, you would see many times more flow in high vacuum situations.
Michael Fowler
Registered User
Is there a way to extend the CDR's output side to the senter of the intake opening? It would seem that getting the oily vapors to the center would distribute them more evenly, and eliminate the higher temps in the rear 2 cylinders.
Has anyone found a way to safely do this? I do not want a piece of pipe smaking an intake valve.
Has anyone found a way to safely do this? I do not want a piece of pipe smaking an intake valve.
sle2115
NRA LIFE MEMBER
I think that the gravitational pull is an issue as well. When the oil enters the intake, it naturally goes toward the rear because of the forward motion of the truck. I suppose you could drive in reverse all the time and fix the problem!
Having had a bad CDR on my truck, I can tell you of two times that I had it overheat the back two cylinders. Both times I was pulling a pontoon up a long, steep hill. While it wasn't floor boarded, it wasn't far from it. Both times, I started to smell antifreeze burning, then the truck started making steam out the exhaust. I topped the hill, and for about a mile it made the steam and smelled of antifreeze. I took off the breather when I got to my destination and the intake was VERY oily.
Now, in contrast to what Zigg said, to some extent anyways, my truck makes VERY little blow by when running, idling or with RPM's up through the oil filler tube. It has about 140,000 on it and I don't believe for a moment it was babied for any of those miles. That being said, I changed the CDR valve, pulled the pontoon up the same hill at least 20 more times, as well as MUCH more weight (I hauled 6 tons of logs up the same hill, the pontoon weighed less than 3000 lbs.) up the same hill, ran it the same and even harder, and NEVER had the same thing happen. I agree with what Zigg says, don't get me wrong, but I do believe they go bad and as a result, get oil in the intake. My thought, after seeing Zigg's picture some time ago, is that the diaphragm (which I think most will agree is there for HIGH vacuum situations to keep large amount of oil from entering the intake) goes bad and then when you really work the motor and make vacuum, oil bypasses or goes through the hole in the diaphragm, causing what I experienced.
My guess is that repeated exposure to this heavy oil-intake contamination would cause catastrophic head gasket failure!!!
