I removed my CDR valve to clean it, because I don't know if it was ever done. It has grey paint overspray on it, so I'm guessing it's the original. My question is, how do I know if it's still working correctly? I can EASILY breathe through it in either direction, yet I see a spring inside when I look in the end. Should there be some resistance in one direction? I have some shop service books but they are no help at all. If anyone can help me out, I'd rather not buy a new one if I don't need it.
Testing CDR valve?
- Thread starter flybear
- Start date
Mr_Roboto
Full Access Member
The CDR only closes under high vacuum.
You're best off just replacing it with new, then cleaning at a regular interval.
You're best off just replacing it with new, then cleaning at a regular interval.
but it has worked for me.
Andylad13
DieselBoy
its working.
LUCKY_LARUE60
Full Access Member
I wonder how high of a vacume it takes to close the CDR?????????????
Well , since it's supposed to close above 2000 rpms, I guess someone could tap a vacuum gauge in to the intake and wind it up to 2000 rpm and see what it reads, that should tell you what it should take to close the CDR.
At least it works great on paper
At least it works great on paper
Optikalillushun
Registered User
can one get a CDR valve anywhere or is it a dealer style only item? mine was never replaced and while in doing everything i might as well do it...after all it has been 20 yrs hehe
our CDR's are made by AC Delco....yes...it's a GM product
there's a 18xxxxx number on the back of it. Any ACdelco dealer can get it for you with the number. I usually change mime out every 50k.
Optikalillushun
Registered User
i rememebr reading about something the 6.2 diesels used, supposed to be better then a CDR? i need to find that book...
Optikalillushun
Registered User
i found one from Ford...now what about the rest of the CDR set up like the little band clamp and some kind of plastic washer? do they come with the new CDR or can u buy them seperatly.
Optikalillushun
Registered User
TTT, by the way i got one from Napa but it isnt 100% exact. it doesnt have the wings to bolt it to the intake and the neck on the flat side is longer...it was from a 6.5 heavy chevy. guess its going back
oldmisterbill
Grumpy Old Man
Take the CDR out clean it there is a real small hole on the outside of the diaphram.I pull a vacume on it if it holds it is ok. What ur doing is checking the diaphram for leaks.
Evil_Jester
it wont die...
A diesel tech told me once, if u look into the intake and see oil, like alot of oil then you need a new CDR(but this is commin from the guy that forgot to put oil in a 6.0 and tried to go for a drive). Ive also heard you can clean them, but i never heard how.
