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I just spent the last four hours reading about PCV valves and how they work. It seems like everyone's setup is different. Some guys are running different air cleaners or valve covers or oil fill tubes. Let's not even start to mention the dreaded Road Tube.

Well here is my question. Let me start with the setup I am going to run. I have a 67 block and a 67 intake. The valve covers are the scripted type with no holes for anything. The oil fill tube is from what I believe to be the "open" system, that is there in NO bung on the side of the fill tube for the PCV. My block has been pluged where the adapter would go. So I need to resolve the dreaded PCV issue.

From different posters on this subject (Sauron, JohnZ, and Vintage 68:thumbsup:) I think that I may have a better grasp on where I need to go. The PCV system needs to have the intake side and an exhaust side (I think).

I am thinking of the intake side for my setup would be the regular oil fill tube with the vented cap (standard "open" 67 system).

The exhaust side I was thinking that I should unplug the hole by the distributor (sp) and insert the "adapter" (whatever the hell that thing is) and run that to the vacuum to the Quadrojet carb that I am going to run that I don't currently have.

Will this solve the dreaded PCV question? The problem is I am not sure of where to get the "adapter" that would go on the back of the engine. I did read one post that talked about a "dixie cup".... where would I get that?

Also I am under the impression that there are different kinds of PCV valves? which one would I need? part number? can I go to autozone and get it or sould I get a "Quality" one from a speed shop.

This is for a 67 Camaro. I am trying to get this as close to factory as possible so cutting hole into the VC are not an option. I could cut into the air cleaner but I think that that is done on the "closed" system, reverse PCV.

Am I close to what I need to do to get this engine to breath properly and not blow gaskets and stuff...

Thanks for reading my long winded question.....Seriously I have a headache from reading all these posts on this subject. I went through five pages of past PCV stuff..... I think I need a beer..:beers:

Thanks....
Brandan-:)
 

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Your 1967 didn't originally have a PCV valve. It indeed, used the 'road draft' tube set-up. Chevy went to the closed PCV system (which used a PCV valve) in 68.

You can use the original set-up for crankcase ventilation for your 67, but if it were me, I would find some 1968+ SB valve covers and run a PCV system that uses the valve.

You can remove the oil fill tube and block the opening on the intake manifold with a 1.25" (I think) freeze plug. Same with the draft tube in the back of the block.

Then you can get a PCV valve and grommet for your driver's side valve cover and either a breather (can be messy) on the passenger's side VC, or plumb it to your air-cleaner if it has a provision.

The closed PCV system has many advantages; reduces crankcase pressure and oil leaks, does a muuuch better job of removing harmful blowby vapors from the crankcase, and there's no mess under the car where the draft-tube delivers it's vapors.
 

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Your 1967 didn't originally have a PCV valve. It indeed, used the 'road draft' tube set-up.
Nope. The "road draft tube" arrangement disappeared after 1962. '67 V-8's used a "partially-closed" PCV system, as shown in the '67 Assembly Manual (UPC 6, sheet C5). They used the "dixie cup" adapter on the rear block vent hole, with a hose to an elbow that screwed into the back of the 2-barrel carb; that elbow had a calibrated orifice in it (usually .090") to meter the flow of crankcase vapors from the "exhaust" side of the system instead of a PCV valve.

The "intake" side of the system was the vented oil fill cap on the oil fill tube.

The L30 and L48 (Q-Jet carbs) also used the "dixie cup" adapter, but its hose had an in-line PCV valve with the other end of the hose connecting to the nipple on the front of the carb base.

With RPO K-24 (Positive Ventilation), a different rear vent tube was used at the block rear vent hole, which connected via a hose to the air cleaner base for the "intake" side of the system. For the "exhaust" side, they used a different oil fill tube with a bung that accepted a screw-in PCV valve, a sealed cap, and a hose from the PCV valve to the carb. The 2-barrel used an elbow (with no calibrated orifice) at the back of the carb base, and the L30 and L48 (Q-Jet) used a hose to the nipple on the front of the carb base (Assembly Manual, section K24, sheet A2).

The K-24 approach will provide a fully-functioning PCV system without having to alter the valve covers. :)

:beers:
 

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Great explanation, JohnZ.:beers:

Brandan, you can purchase the PCV valve for a 67 327 at just about any parts store. I bought mine at Autozone. I think I have an extra dixie cup. I'll check for you next time I'm in the garage. Then a couple pieces of hose and a vented oil fill cap and you are good to go. :thumbsup:
 

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Discussion Starter #6
Guys thanks for the replies.... I don't think that I mentioned that I was going with the 4 barrel quadrojet. With that being said, the "dixie cup".. is that something that I can purchase from say Autozone or somewhere else?? (in case Tom doesn't have one). I did a search on ebay just to see what it looked like and came up empty, just real paper dixie cups...:mad:

I did see Johns post from a few years ago that showed a picture if it installed. I did find a part on Rick's.. not sure if that is what I am missing.

Here is the link http://www.rickscamaros.com/camaro-crankcase-vent-tube-small-block-with-spark-plug-wire-stand-for-cars-with-pcv-and-without-a-i-r-pump-1967.html Is this the part that I am missing? or will it work..???

My plan was to keep the "intake" side of the PCV with the vented oil fill tube.

The "exhaust" side... well that is my dilemma. I am kind of confused of what I need to do. I am thinking that I need the Dixie cup (like John is saying) that should go to the base of the quadrojet 4 bbl carb. Does this sound right? I asked my engine builder and he was not familiar with the Dixie cup...

Brandan-
 

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Yes, you have it right. The one shown in the link is too big, mine has a much shorter pipe only 2 inches or so, as does my extra one. If you have the AIM you can see it on one of the drawings for L30. I just don't have it in front of me right now...Dixie->hose->pcv valve (held by a bracket to an intake bolt)->smaller hose-> front base of QJet.

I don't see the dixie cup in the NPD catalog either so I doubt you can get that at AZone.
 

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Discussion Starter #8
Ok, so I need the dixie cup in order to get this to work....


Exhaust side: Dixie cup from block to fitting on quadrojet should do the trick.....


Tom did you find your extra? and if so PM the details... My engine is on hold until I get this resolved.:clonk:

Is there a different name for the "dixie cup"? Is this a GM part?

Thanks Brandan-
 

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... Is there a different name for the "dixie cup"? Is this a GM part? ...
:yes: Group 1.762 - Tube; Adapter assembly ;)
Discontinued from GM dealers years ago ...
 

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I have seen a small filter/breather used on the back of the block in place of the tube assembly to the air cleaner, along with the sealed cap breather tube with a pcv valve connected to the vacuum port on the carb base. It isn't factory but you wouldn't have to molest your valve covers and would provide a functional PCV system.
 

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I have seen a small filter/breather used on the back of the block in place of the tube assembly to the air cleaner, along with the sealed cap breather tube with a pcv valve connected to the vacuum port on the carb base. It isn't factory but you wouldn't have to molest your valve covers and would provide a functional PCV system.
Dennis, I think that is the "closed" system that John was referring about. I know that it is an option but I am more set up for the "open" system. Just missing the "dixie" cup.

Thanks, at least I have options. A few days ago I thought I was toast and didn't have a direction to go. I swear this site has helped me out a number of times


Brandan-
 

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Discussion Starter #15
That part lives in the lifter valley and keeps oil from being sucked up. If you block is original you should have one there. I had to take mine out when using my Performer intake.
Jeezz.. I am missing that part as well:clonk:...... I think I can skip it and not hurt anything. I have been working on this car for four years now and I am so ready to drive it......:thumbsup:


John, again your knowledge is greatly apprecitated on this.....thank you:beers:



Brandan-
 

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Brandan, I blew it! After turning my garage upside down I remembered I gave it to a guy with a 67 intake I sold him. I'm sorry!:eek:

Maybe somebody else can save the day...?
 

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Tom, thanks for the effort. I am sure that something will come up.... John gave me some numbers here to work with so I will try to find the answer. I did look in the AIM and the page that looks like what I am trying to do was L30 A3. There has to be a GM part number for that adapter valve assembly...

Tom thanks again,................. the search is on!!!!

Brandan-
 

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Discussion Starter #18
I found some catalog part numbers and put a link:

http://chevyinfo.net/parts_books/camaro_1967-73_parts_book/part_numbers/camaro_1967-73_01.000_cooling.pdf

on page nine towards the end it goes into some parts numbers. is 3881848 the "dixie cup?" If I can get a part number than it may be easier to locate said part. I am pretty sure that L30 A3 shows the cup but doesn't list a part number. Also does any one have any idea of where to locate one of these things? Or even a different alternative or solution....

I guess that if I can't find it than I will have to use the closed system. Would that tube (posted pic through link earlier) be the correct tube to go into the air cleaner?

Brandan-
 

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You'll find it much easier to score most the parts you need from the Corvette 'repoppers' like ZIP and Corvette Central ;)
They tend to cater more to the restoration minded folks than the Camaro suppliers - IJMHO of course ...
Here's the link to CC's internal vent canister - http://www.parts123.com/parts123/yb.dll?parta~partsort~1~cadefibD

The "Dixie Cup" adapters are a little harder to find.
No one I am aware of is presently repopping them.
But - they are very easy to find in some of the older wrecking yards, specially a truck oriented yard :thumbsup: - or even on 'eBain' many times.
(The special long bolt for them is available from the Corvette guys above or hit a good hardware store and find one)

The 3rd way around this is pretty easy.
Just get a @1 1/4" rubber grommet (like the ones you'd install in a valve cover) from an auto parts store that has a hole for a PCV valve in it. (A Fram #FV184 PCV works just fine ;) )
Install the grommet in the rear hole, install the PCV into it and then plumb with hose to the carb. base.
Once a 'breather' type cap is installed in the Oil Fill tube or one (or both) of the valve covers, your job is done and the crankcase will breath correctly.

This isn't "Rocket Surgery" - you want a way for fresh air to enter the crankcase (via breather(s) ) and a way to be drawn out under metered conditions (via PCV) and 'viola', no more oily mess and issues with oil control from blow-by ...

(EDIT)
That tube assembly you posted is for the GM RPO-K24 Closed system - and the 'Heartburn' pricing is WAY HIGHER than the normal Corvette-guy suppliers pricing :eek:
Way to much work to adapt ...
 
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