CDR Valve

[sprice]

Is a CDR (Crankcase Depression Regulator)Valve necessary when I have no emission laws telling me it has to be there? Can it be replaced with a breather element? Mine is sucking a ton of oil through the turbo and I don't have $80 for a new one.

[JeepSJ]

Good question. I have my CDR vented through a breather - I don't have it attached to my intake tract. I just discovered a little issue with blow-by and the CDR doesn't seem to be able to flow enough and I'm pushing oil out through my timing cover gasket. I fired it up without the CDR last night and it stopped pushing the oil. I have thought about removing the CDR until I can get the blow-by issue resolved.

[RoverIIa]

Have you tried cleaning it out?

I don't know if it would work, but it seems like a few squirts of WD or brake cleaner might help?

cheaper than $80.

I think mine was a lot less than that a NAPA though.

[gmctd]

Remove the CDR cannister, clean the tube end that fits into the valve-cover, then blow thru the CDR to get a sense of any restriction thru the device.

Your engine burns a light oil as fuel - what possible detriment could oil vapors from the crankcase have on that process?

Maybe add a few mpg would be the only 'detriment' I can imagine.

If the engine is unexplainably bucking and surging on the hiway, could be excess blowby, but changing the CDR will not cure that problem.

Remember - the accumulation of oil in the compressor inlet and intake plenum is from the day the vehicle rolled off the assembly line - do some routine maintenance, try cleaning things up, then see how it looks in a month's time.

Dirty air filter will increase the vapor 'draw-thru', even pulling raw oil from the valve-cover.

If it's a heavy accumulation within that month's time period, imagine what your engine bay will look like with a breather cap installed.

Besides, that CDR system provides a slight vacuum in the crankcase which prevents main-seal leaks - well-maintained 6.5's are known as dripless Diesels.

Remove the cap from the oil-fill tube, engine idling at operating temperature, to determine the condition of the engine - light haze is ok for a hi-mileage Diesel engine

[Billman]

Spoken like the True 'CDR King' that you are...

[gmctd]

:) Hey, Billman - long time no post, dude - everything been ok?

Yeah, I'm still anti dual chrome breathers - you-know-who's Tahoe soon bit the dust, as it were, but no word as to cause and effect.

Coulda been them tricky little silicates - PCM's full of 'em, but engine bearings don't like 'em, much.