missing parts

[FredM]

my J engine in a 87 R30 has a hole in the passenger side valve cover, what goes there? because no other one i've seen has a hole and GM parts fiche shows no hole. secondly is there another possible location for the glow plug controller its not on the fender by the washer jug.

[NH2112]

I'm not sure which year they did it, but GM moved the CRD valve from above the alternator to the valve cover, and got rid of one of the hoses to the intake manifold at the same time. You might have a later valve cover on your engine.

As far as the glow controller, I think they're all at the back of the driver's side head on 85-93 models. I could be wrong about vans (if that's what an R30 is), though. It could be a pain to access if in that spot, although there's little that isn't a pain to access on a van engine!

[gavio]

If indeed an R30 is some kind of van or step van or whatever, then the glow controller would live on the back of the driver's cylinder head, or on a bracket attached to the intake manifold bolts at that corner of the engine.

And Phil's right, there's little that's not hard to get to on a van engine, except the vacuum pump!

Good Luck!

[EWC]

R and V series are the designation for the older box style body trucks , R being 2 WD and V for 4WD . They were produced , along with the CK series , until 91 in the crewcab and Suburban platforms in 2500 and 3500 series trucks .

The hole in the valve cover is for the CDR valve , as the others have stated , and I think that started in 88-89 in the newer CK series truck .

The relay should be on the back left side of the head bolted to the blockoff plate for the cooling system .

[FredM]

thankyou, yes also called a cab and chassis, whats a CDR valve where does it go to, chapter 12 on glow systems says "glow controller rear of cylinder head and the glow plug relay is on fender" there's nothing mounted on my fender.

[arveetek]

Only 82-84 year trucks utilized a separate relay mounted on the fender as your information states. In '85 and later models, the controller and relay are made into one unit located on the rear of the driver's side head....no separate relay.

The CDR is the valve that relieves crankcase pressure. In simple terms, it serves the same purpose as the PCV system on a gasser....it's the valve that allows crankcase vapors to enter the intake to be burned, and it keeps the crankcase relieved of pressure. Do a search on "CDR" to learn more about it and how it works (I hope that info wasn't lost in the recent forum failure?).

Casey

[FredM]

thankyou i was in the wrong chapter duh, the assembly at the top front of the engine where you fill in oil that has a canister like attachment is not the crankcase depression regulator? i'm beginning to understand why there is engine oil sprayed from front to back.

[NH2112]

If you have the tuna-can-sized CDR valve above the alternator, with a hose between it and the oil fill tube, then you definitely have the wrong passenger-side valve cover.

[FredM]

thanks Phil, yes i have tuna, where roughly would the hole in the intake manifold be? tranny lazy to go into third for lack of vacuum, i think, also one small hose up top looking for a spot.

[catmandoo]

hole should be on the pass side right under the aircleaner lip also i'm guessin on the hose it's probably the egr hose that goes thru the aircleaner and to the egr mounted in the top of the intake under the aircleaner.

[Ratau]

How do one test the CDR valve?

[britannic]

Originally posted by Ratau:
How do one test the CDR valve? Use a manometer or a clear PVC U tube with enging oil in it and attach it to the dipstick tube and run the engine. A good reason to use oil in the tube, is in case the CDRV is allowing too much vacuum and the contents of the U tube are sucked into the engine.

Here's an excerpt from gmctd's post about CDR operation:

...
The CDR functions to limit crankcase vacuum to 4" to 6" on the water column.
27" of water = 1psi
2" mercury = 1psi
...

[FredM]

ok, thanks again there is obviously a problem because of all the oil everywhere, can CDR's be rebuilt and/or which of the two types should i get i'll plug the holes and double check first.

[Dieselboy]

Based on that same thread JD put together, I think the part number you need is: 25097699

Double check that, but it's a valid number of GMpartsDirect.com

[britannic]

Originally posted by FredM:
ok, thanks again there is obviously a problem because of all the oil everywhere, can CDR's be rebuilt and/or which of the two types should i get i'll plug the holes and double check first. The CDRV can only be cleaned, since they're not designed to be disassembled, don't use a chemical solvent though, otherwise the diaphragm will be destroyed.