66-68 bb pcv valve tag
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Re: 66-68 bb pcv valve tag
Stephen, in 1967 there was two PCV used CV736C and the CV 691C state in Judging manual i don't think there ever was a label that stated CV691 if there is i would like to see a original one for a CV691 maybe someone can post one to view, by the way the CV736 and CV691 are the exactly PCV valve, that my Details ?Last edited by Danny P.; October 30, 2021, 11:49 AM.- Top
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Re: 66-68 bb pcv valve tag
Danny,
I don't know if this label is original or not.....PCV 691 label....... again, possibly a C2 judge can chime in..........
By the way, there is a difference between CV691 and CV736...... a different vacuum rating...... is it significant? I don't know....Attached Files- Top
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Re: 66-68 bb pcv valve tag
Danny,
I don't know if this label is original or not.....PCV 691 label....... again, possibly a C2 judge can chime in..........
By the way, there is a difference between CV691 and CV736...... a different vacuum rating...... is it significant? I don't know....- Top
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Re: 66-68 bb pcv valve tag
Judges don't remove the PCV valve from the valve cover during judging. Therefore they can't make the comparison. How do you know the PCV 691 label isn't original???????- Top
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Re: 66-68 bb pcv valve tag
NCRS Mechanical Judging don't pull the PCV but they know, there just looking for the proper orange and white tag and the spring clamps, but Judging ask to remove the oil Cap to see under if tabs are right , just looking at that CV691 Tag its not Original someone cut out looks like gasket paper and stamp the numbers on it, its not original.- Top
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Re: 66-68 bb pcv valve tag
Danny,
Attached are photos of a correct PCV valve tag for #736 & #691.
1966 BB and early 1967 BB used a #691 valve and tag.
1967 BB and 1968 BB used a #736 valve and tag.
If your car has a #736 valve then it should have a #736 Tag. The opposite is true if you have a #691 valve. It should have a #691 Tag.
Your car, in an earlier post, had a mix of the 2....a #736 valve tag with a #691 valve.
I've also attached a portion of the 1966 Judging manual for reference. The 1967 manual has a similar statement.- Top
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Re: 66-68 bb pcv valve tag
Danny,
Attached are photos of a correct PCV valve tag for #736 & #691.
1966 BB and early 1967 BB used a #691 valve and tag.
1967 BB and 1968 BB used a #736 valve and tag.
If your car has a #736 valve then it should have a #736 Tag. The opposite is true if you have a #691 valve. It should have a #691 Tag.
Your car, in an earlier post, had a mix of the 2....a #736 valve tag with a #691 valve.
I've also attached a portion of the 1966 Judging manual for reference. The 1967 manual has a similar statement.
Thanks Stephen, 1967 Judging is looking for Orange paper with white lettering says TYPE-CV-736C they don't Judge the PCV Valve, but of course you would need the the proper Label stating #691 tag if you were being Judge as a 1966, i will confirm with Mechanical judging if i would lose any points if i flip over to a 691 tag label on a 67 when being Judge , in 67 early cars came with #691 then later where #736, Danny- Top
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Re: 66-68 bb pcv valve tag
If the PCV is the flat top design, maybe they assume it has the correct part number matching the tag.- Top
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Re: 66-68 bb pcv valve tag
My takeaway from this thread is this tag is not original. Correct?
Tim
Attached Files- Top
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Re: 66-68 bb pcv valve tag
Being bored in a Georgia campground for 3 days now, waiting until this southern Nor'easter departs, I did some research on the PCV. In the 1966 and 1967 AIMS, the part number for the PCV is identical for the 427 BB engines(L36/L72 and L36/L71). In the 1966 AIM next to the PCV part#, 6423438, there is Note 11(circled), but my digital copy of the page is poor quality and I can't see it. Maybe this was a change from the CV-691 PCV later in 1966.
Part# 6423438 VALVE ASSY is not shown anywhere in my online Parts Book references on gmparstwiki.
Maybe someone can confirm, but I suspect this part number was never available in Service.
I suspect the "ASSY", as referenced in the AIMs, included the label that we're discussing, and the reason that the label is never shown as a separate part# in the AIMS.
Service PCVs are shown under Group 1.745 in the Parts Books. E.G. HERE. The CV-736C is shown as GM Part# 6423695. Here is a file photo of a NOS example. There is no label included in the Service part, and it is not referenced as a "ASSY", simply "VALVE, VENT". Note that the NOS service parts are stamped steel, not machined as originally equipped from St Louis.
s-l1600.jpg
Just some info that may be already known by some of you, but it had me thinking ever since I tapped into this thread.
Rich- Top
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Re: 66-68 bb pcv valve tag
Great pics...thank you.
Looks like the upper rad hose and clamp(s) are replacement. We are left to determine accuracy, all these years removed. Who knows what's real? The 65-67 guys do a really good job, based on what (they) we think (they) we know.
KramdenKramden- Top
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