1972 gas cap stamping

[Fred H.]

The gas cap on our 72 LT1 is stamped with an S. I understand OEM 72 gas caps are stamped with the SMC logo. I've been told our gas cap is a service replacement, can anyone in the group confirm? I would hope having a GM service replacement when judged, would result in a notation / minor deduction?


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[Edward J.]

Re: 1972 gas cap stamping

Fred,Yes that is a service replacement. I think that you can find a newer service replacement with the correct stamp. The only thing it has a gold dichromate finish. I believe that dull silver cad. Finish is correct. Take a look on eBay.

[Ray K.]

Re: 1972 gas cap stamping

Fred,
Not sure if they're the same, but, here are photos of my '71 &LT1 fuel cap. Note the logo on the bottom side.
I owned my vette since day one, so I know it's an original.
Ray K (#43777)

[Fred H.]

Re: 1972 gas cap stamping

Positively your cap is OEM. I believe the 71 cap has the red "open slowly caution" the 72's the "open slowly caution" was a stamping (No Red).

I think that yours with the red label is 71 only. Thanks for your reply.

[Leonard M.]

Re: 1972 gas cap stamping

Fred, I am pretty sure, but can't say 100% that the 72 cap should have a yellow dichromate coat on top of the zinc; as seen on the 7K 98.9 top flight I once owned.
Ray's 71 cap is correct for sure, but I think more pretty than it left the factory. The 70 and 71 caps had the scalloped edge and were stamped sealed. In 72 it was stamped sealed, but the outer edge was smooth. 71 had the aluminum open slowly plate; not a decal as commonly mentioned. All had a rubber gasket.
Even though the Slant logo is not original, why worry as the cap is not removed for judging. If you wanted an original, I'd say it would not be to hard to find and you can get it replated and dipped to be factory correct and match the condition of your car.
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[Leif A.]

Re: 1972 gas cap stamping

A '71 cap that came on my '67. I traded it to Pete Lindahl 10 years ago for a correct, restored cap for my '67.

[Fred H.]

Re: 1972 gas cap stamping

Hi Lenny, thanks for always sharing your knowledge. At this point we haven't received a deduction with our present cap. I might go over the David Sokolowski's and look around. Talk to you soon

[Mark F.]

Re: 1972 gas cap stamping

Just out of curiosity, what's the reason for the "OPEN SLOWLY - CAUTION" label ?

I understand on hot days, vapor pressure at the cap could be hi - but I'm not sure what the hazard is if you open it QUICKLY ?

[Joe L.]

Re: 1972 gas cap stamping

A '71 cap that came on my '67. I traded it to Pete Lindahl 10 years ago for a correct, restored cap for my '67.

Leif------


Assuming that your 1967 had its original (or, exact replacement) fuel tank, it's a good thing that you replaced it with an original cap and aside from the aspect of originality.

The 1971 fuel cap, GM #3983384, is a SEALED cap (as it is clearly marked). That's because the 1971 fuel tanks had an integral pressure/vacuum valve. Original 1967 fuel tanks (and, exact replacements) had no integral pressure vacuum valve. So, using a 1971 cap on a 1967 tank means that your fuel tank had no venting, at all. Not a good thing.

[Bill B.]

Re: 1972 gas cap stamping

Hi Mark,

I believe that if the pressure was sufficient, it could fly up out of control of the person removing and land on the back deck of the car, thus causing damage to the paint/fiberglass. If it was a Warning, instead of Caution, personal injury would have been implied.

[Jeffrey A.]

Re: 1972 gas cap stamping

72 also has a dull cadmium or zinc finish cap with the Stant logo. Yellow dichromate finish caps are service replacements or reproductions.

This is my factory 72 gas cap, not perfect in shape but okay.
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