CDR bypass.

[wayne pick]

After resealing the engine on my m1031, I decided to bypass the CDR valve as I figured it was the cause of a few oil leaks. I replaced the rear main seal, timing cover, and oil pan gaskets. On the Banks turbo setup, the CDR plumbing is routed back into the air filter box, and created a real mess.

The engine seems to run better with the CDR disconnected. The turbo spools up quicker, and the engine runs smooth with less noise. Any pro, or cons on doing this? I used the existing plumbing to vent the vapors into a gallon oil bottle to avoid making an oil mess on the ground. Any input would be great. Happy new year guys!

 

[doghead]

Google cdr, and read why they are used.

I Have posted the info before. You need it.

 

[topgun217]

CDR Valves "suck" but you do need it/one on your truck. Easy fix is to buy a new one from an auto parts store. Just look at it first before leaving the store to make sure you have the same type. I had to have mine ordered took two days, first one was not the same type.
(just my 2 cents) "Always Trust the DOG"

 

[Nuke113]

Is there any particular reason why the hole in the intake cannot be plugged and a standard breather hose attached for the vapors? From what I've read, and please correct if wrong, is that the CDR valve prevents the intake from drawing too high a vacuum on the crankcase so following this is there a reason one cannot just vent the crankcase vapors directly to the atmosphere instead of sucking them into the intake? If this is way off base please inform why this is my first hands on with a diesel but with gas engines we would always just vent it directly.

 

[Hasdrubal]

The CDR valve regulates the amount of pressure or blowby from the crankcase back to the intake. The purpose of the CDR valve is to maintain 0" to -4" inches of vacuum in the crankcase at all engine speeds. This is a maintenance item and should be replaced or cleaned every 30K miles as recommended. 6.2/6.5 diesels need to run a slight vacuum in the crankcase and this valve regulates that. When this valve fails, the engine seals no longer have a steady low vacuum against them, and often the rear main seal will start to leak. Likewise excessive external engine oil leaks due to pressurizing the crankcase.

 

[doghead]

http://www.steelsoldiers.com/showthread.php?107933-Crankcase-Vent&highlight=base+pressure

 

[doghead]

I must ask, did you search before posting?

 

[Nuke113]

Yes read the first few pages of search results and the diesel place postings though the one you posted just now eluded me though it still didn't quite answer the question. I didn't realize that the engines were designed to have a slight vacuum in them and that was my question whether it was a design point or simply emissions.

 

[phil2968]

Remember, diesel's do not develop intake vacuum like gas engines do. No vacuum to draw the vapors from the crankcase.

 

[wayne pick]

Thanks to all that replied, notably, doghead who's advice I would never question. Guess I'm replacing this mystery valve! Lol!

 

[doghead]

It's good to question, that is how you learn!