CDR valve from NAPA questions and other tune up questions

[ssgtcampbell77]

These guys here in St Louis (NAPA, Auto Zone, Advanced Auto, OReillys) all tell me they don't have this part. I thought maybe there was another name for the CDR.

 

[epitts]

Can theses items be cleaned with anything?

 

[Grega]

I think that no body makes a CDR valve any more. But watch on e-bay and they will be one on there from time to time, usually old GM stock. There have been many post on this site about this, do a search.

 

[jdemaris]

The CDR valves for 6.2s are for sale at many parts stores. In fact, Rock Auto has two brands for sale. The "wholesale closeout" CDRs are only $1 each. The Standard Motor brand ,V335 (GM #25097699) is $34.
NAPA sells them under the Echlin brand name.

All over the place with prices ranging from $1 to $80 - all for the same part.
Standard Motor # V335 Echlin/NAPA # CRB 29445 GM # 25097699


No problem buying them, but I AM wonderiing why so many want them? I've got over 20 trucks with 6.2 diesels I've been driving for 15-20 years. I have never changed a CDR valve, although I clean them now and then. When they don't work, the rear main oil seal will start to leak.


STANDARD MOTOR PRODUCTS Part # V335 More Info {#25097699}
Crankcase Depression Regulator Valve, 3 1/2 Inch Dia. Canister Type $34
GUARANTEED PARTS Part # PCV80
PCV Valve CRANKCASE DEPRESSION REGULATOR VALVE - 3 1/2" DIA CANISTER TYPE [Wholesaler Closeout -- 30 Day Warranty] (Only 7 Remaining)
$1.06 each, brand new
http://www.rockauto.com/catalog/catalog.php
　
http://www.gmpartsgiant.com/parts/gm-valve-cr-25097699.html $58
http://www.napaonline.com/Search/Results.aspx?Ntt=V335&Ntk=Interchange%20Number&Nty=1&N=0
CRB 29445 $46
http://www.autopartswarehouse.com/details/QQGMCQQK1500QQStandardQQPCV_ValveQQ19881998QQSIV335.html $72

 

[Warthog]

Just remember that these are NOT the stock CDRs that the military used. They will work but mount differently.

 

[jdemaris]

Just remember that these are NOT the stock CDRs that the military used. They will work but mount differently.

Actually the new one I posted an image of IS what the military would of used as a new replacement part in the 1990s. GM/AC Delco changed it a bit, as they do with many parts. In fact, they are probably made by CAV and GM/Delco just reboxes them.

The new CDR has a shorter metal nipple on it, but otherwise is sold as a direct replacement for the pre-1985 CDRS, post 1985 civilian, and the military style. Early civilian 6.2s have the CDR moutned up in the air with two rubber hoses. later civilian 6.2s have one end directly hooked to a valve-cover grommet at pass-front. Most military rigs have it mounted abouve the rear of the pass-side valve cover.

 

[chief1983]

Hey Campbell, you going to the Troy mud run this year? We might have to get the MVs together

The CDR valves for 6.2s are for sale at many parts stores. In fact, Rock Auto has two brands for sale. The "wholesale closeout" CDRs are only $1 each. The Standard Motor brand ,V335 (GM #25097699) is $34.
NAPA sells them under the Echlin brand name.

All over the place with prices ranging from $1 to $80 - all for the same part.
Standard Motor # V335 Echlin/NAPA # CRB 29445 GM # 25097699


No problem buying them, but I AM wonderiing why so many want them? I've got over 20 trucks with 6.2 diesels I've been driving for 15-20 years. I have never changed a CDR valve, although I clean them now and then. When they don't work, the rear main oil seal will start to leak.


STANDARD MOTOR PRODUCTS Part # V335 More Info {#25097699}
Crankcase Depression Regulator Valve, 3 1/2 Inch Dia. Canister Type $34
GUARANTEED PARTS Part # PCV80
PCV Valve CRANKCASE DEPRESSION REGULATOR VALVE - 3 1/2" DIA CANISTER TYPE [Wholesaler Closeout -- 30 Day Warranty] (Only 7 Remaining)
$1.06 each, brand new
http://www.rockauto.com/catalog/catalog.php
　
http://www.gmpartsgiant.com/parts/gm-valve-cr-25097699.html $58
http://www.napaonline.com/Search/Results.aspx?Ntt=V335&Ntk=Interchange%20Number&Nty=1&N=0
CRB 29445 $46
http://www.autopartswarehouse.com/details/QQGMCQQK1500QQStandardQQPCV_ValveQQ19881998QQSIV335.html $72

Might be why my rear main is leaking. Crap. Well, if my oil pump is shot I was going to replace it anyway, but good to know the cause so I can prevent it from happening again, or getting worse.

 

[chief1983]

The PCV80 from Rock Auto is _not_ a CDR valve. It is a PCV valve, for what, I have no idea. I know because I just bought one. Oh well, only out a few bucks on that one. The V335 one for $34 at least has a picture with it, so I might try that one next. Anyone else verify that any of those actually work yet?

 

[ssgtcampbell77]

Hey Campbell, you going to the Troy mud run this year? We might have to get the MVs together



Do you know when it is? I will absolutely be there if Im in the state at the time.

 

[jdemaris]

The PCV80 from Rock Auto is _not_ a CDR valve. It is a PCV valve, for what, I have no idea. I know because I just bought one. Oh well, only out a few bucks on that one. The V335 one for $34 at least has a picture with it, so I might try that one next. Anyone else verify that any of those actually work yet?

Yeah, I got four of them. They are just gas-engine PCV valves. Just took one phone call and they refunded all my money and told me to keep them. Those parts WERE described as CDR valves with 3 1/2" cannisters. That was done by the wholesaler, not Rock Auto.

Funny thing is, the Rock Auto guy told me that somebody else bought the same part for a diesel and didn't complain. Maybe that was you?

Rock Auto does have the correct CDR under a different brand, but it's more money.

 

[chief1983]

Could have been me, but it was so cheap I didn't bother. I missed the part where they were described as 3.5" cannisters though. It's probably the $34 one that was mentioned that's the right one.

 

[jdemaris]

Could have been me, but it was so cheap I didn't bother. I missed the part where they were described as 3.5" cannisters though. It's probably the $34 one that was mentioned that's the right one.

No sense throwing your money away. One phone call and they're refund your money.

For mine the shipping was more then the parts. $12.05 shipping and $4.04 for the parts. That's why they told me to just keep them and they gave me a full refund. It wasn't worth it to them, to send them back.

Rock Auto now only shows the one brand, with the photo. It's listed under the main heading as a PCV vavle, but as a CDR in the full description. Only GM diesel that actually ever used a PCV was the Olds diesels in the 70s.

STANDARD MOTOR PRODUCTS Part # V335 Crankcase Depression Regulator Valve, 3 1/2 Inch Dia. Canister Type $33.79

 

[AJMBLAZER]

NAPA # for the Crankcase Depression Regulator Valve in a 6.2 diesel is CRB 29445. Cost $45.99.

Why do you think you need one? Is your rear main seal dripping oil? That's usually the only symptom.

Crankcase Depression Regulator Vavle is available from many places, including NAPA. There are two versions on 6.2s, early and late. The mounting differs on the two. Late ones attach directly to the pass-side valve cover. Early ones aer hose mounted.

Late type is NAPA CRB 29445. Other numbers including GM are:
25098706 ,25042443 ,25042462, CV871

A PCV valve (positive crankcaes ventilation) does not exisit on 6.2 diesels. 6.2 uses the CDR valve (crankcase depression regulator) valve.

I purchased one of those for Big Ugly once. Didn't work. Didn't line up with anything, the hose didn't fit, and the hole in the valve cover was larger than either of the nipples on the "CDR Valve".

Did yours actually work? Every time we have this discussion someone brings up these NAPA things but no one has ever actually said they got one to work.

I purchased an ACDelco CDR from Rock Auto a few years back when they were still selling NOS they had. Then I got in on a deal with the member on here who had hundreds of them. I have a lifetime supply now but no clue where to get more.

If all else fails the newer solution is a 6.5L p-side valve cover and a 6.5L CDR which are still available and more common. Bit of work to change over to though. Better than having nothing or a clogged CDR.

Can theses items be cleaned with anything?

No. Any solvent eats at the diaphram inside. An Army MT mechanic buddy of mine said his guys just tossed them after learning they were just destroying them by spraying cleaner in them.

 

[jdemaris]

If all else fails the newer solution is a 6.5L p-side valve cover and a 6.5L CDR which are still available and more common. .

The V335 CDR valve that Rock Auto sells fits 6.2s and 6.5s. Note that some later 6.2s use a CDR plugged into the pass-side valve-cover, just like some 6.5s.

The V335 also back-fits the older 6.2s that used the CDR with the longer stem. You just have to adapt with some extra hose.

I currently have over 20 6.2 powered vehicles and have been driving them since they were first invented. CDR is something I hardly ever mess with. I'm kind of suprised at all the concern over it. When it ceases to function, the engine seals no longer have a steady low vacuum against them, and often the rear main seal will start to leak. That's about the only symptom I know of, when a CDR is not doing it's job.

Yes, GM used to say to change the CDR at every "tune up." But, GM said many things - some valid, some not.

 

[AJMBLAZER]

I have a '89 K5 with a 6.2L. I'm currently using a CUCV CDR in it. The CDR is in the same place as my M1008's was. Only setup that I know of different were the early double plane intakes.

So are you actually using THESE NAPA CDR's? You never did actually state that.

CDR's are supposed to replaced every 50k or so last I heard. Have heard military, GM, and professional diesel mechanics say the same thing. YMMV. I know the one on my 55k CUCV and the one on my 187k K5 were both rather gunked up.

Anyway, whatever that NAPA part is...it's not a DIRECT replacement.

 

[jdemaris]

Oil filler cap stops the CDR from working

So are you actually using THESE NAPA CDR's? You never did actually state that.

CDR's are supposed to replaced every 50k or so last I heard. Have heard military, GM, and professional diesel mechanics say the same thing. YMMV. I know the one on my 55k CUCV and the one on my 187k K5 were both rather gunked up.

Anyway, whatever that NAPA part is...it's not a DIRECT replacement.

I've got a 6.2 in my "engine pile" that has a CDR vavle on it that the guy bought from NAPA. Needed a 1" longer rubber hose to fit.

In regard to me actually buying one recently and using it? Yes, I bought one from Rock Auto a while back for a new installation I was doing with a Banks turbo. I only bought the new one because I had NO old one.

If you are defining "direct replacment" as a part that is 100% the same as the part it's replacing that may be 30 years old, then I guess many new parts are not "direct replacements." Many get changed to fit multiple applications,, upgraded, etc. So YES . . the new CDR is intended to replace all the older ones. And NO, it will not fit all 6.2s without a little bit of effort.

In regard to what GM recommended or what some mechanics say? Different people and companies say different things - and often with various motives.

I've been a diesel mechanic for over 40 years. As to the CDRs in 6.2s? GM used to say to change the CDR and the oil filler cap every 30K-40K miles. Is it necessary? NO. If it was, my 87 diesel Suburban would not have made it to 520,000 miles with the original CDR valve.

I suspect that the oil filler caps actually give more trouble then the CDRs. Once the oil filler cap gasket no longer fits tight, the CDR cannot work properly. And a new cap only costs around $1.

One case-in-point. Last summer while on a trip, my loose-fitting oil cap fell off the engine. Once off, with no vacuum inside the engine, my rear main seal starting leaking near a gallon an hour. I got to a NAPA, got some oil and a new cap -and it did not leak a drop after that. I near ruined an engine for a cap that cost $1.10. Note the leak was not coming out the oil filller neck. The problem was the lack of a crankcase seal with that cap missing. With a loose or missing cap, the CDR fails to function.

Also about cleaning? I've desludged many and never had a single problem. Early CDRs on 6.2s used to have a problem with getting plugged with sludge and frozen condensation. That's one reason why they got moved on newer 6.2s and 6.5s.

The main function of the CDR valve is to keep a light vacuum against the engine seals. Once the gasket on the oil filler cap gets loose, the CDR fails to do that job.

Earlier GM Oldsmobile 350 diesels used PCV valves instead. but they failed to supply needed vacuum with the engine at low idel speed and leaks occurred. That's why the 6.2 used the CDR system instead.

 

[jdemaris]

What is the fit problem ???

So are you actually using THESE NAPA CDR's?
Anyway, whatever that NAPA part is...it's not a DIRECT replacement.

The CDR valve that NAPA sells as part # CRB 29445 is actually a Delco # CV910. It fits all the 6.2s and 6.5s. It comes with a 3 1/2" cannister and two short steel nipples - each 1" OD.

During the years, GM used at least four slighlty different CDR valves. All were the same diameter cannister, all the same inside, and all with 1" steel nipples for hose or valve cover connections. The only difference was the lengths of the nipples and the angle of bend in some.

By making one CDR with short 1" nipples. this vavle easily fits them all. So yeah, maybe you'll have to add 1" or 2" of rubber hose. Seems that's isn't a huge problem, is it?

I just looked on my shelf and I've got three different CDRs (in a pile of 10 of them).

The CV870 is GM # 25042246, has a 3 1/2" round cannister, and two hose nipples both 1" OD. One is 1 1/2" long and the other is 4 1/2" long with an angle.

The CV871 is GM # 25042443, has a 3 1/2" round cannister, and two hose nipples both 1" OD. One is 1 1/2" long and the other 3 3/4" long.

The CV910 and NAPA CRB 29445 has a 3 1/2" round cannister, and two hose nipples both 1" OD. Both are 7/8" long.

I've cleaned many old CDRs and they worked fine. The metal disk on the vacuum diaphram tends to get sludged up. You can take apart to clean, or - just reach in with a long Que-tip.

 

[jdemaris]

Any solvent eats at the diaphram inside. An Army MT mechanic buddy of mine said his guys just tossed them after learning they were just destroying them by spraying cleaner in them.

I've cleaned many with zero problems. First not any solvent will destroy that diaphram. Second - there really isn't any need to tough the rubber part of the diaphram. The steel disk in the center of it is what does the sealing. You can reach in with a long Q-Tip to clean it, or - just pry the can apart, clean it, and crimp back togeher.

Here's a photo of a CDR I took apart from a 1987 6.2 diesel J-code with 520,000 miles. Sludged up yes- but otherwise fine. Rubber diaphram was still soft and no leaks.

 

[ssgtcampbell77]

NAPA # for the Crankcase Depression Regulator Valve in a 6.2 diesel is CRB 29445. Cost $45.99.

Why do you think you need one? Is your rear main seal dripping oil? That's usually the only symptom.

Yes it is dripping from the rear main. I replace the rear main and it didn't help.

 

[topgun217]

After all this reading, I'm gonna give the long q-tip a try first. Then try ordering one. Thanks for everyones input, it helped me out.