'67 Gas Cap

[Timothy B.]

Re: '67 Gas Cap

Timothy------


I don't recall if there was any difference with respect to the fuel odor in the garage. However, I can say with certainty that there was a big difference in the amount of fuel odors wafting into the passenger compartment during driving. Using the sealed cap virtually eliminated it for me.

Good thing back then everything smelled like gas or exhaust, your hands, clothes, the car in front of you and in a short period of time your girlfriends new clothes she bought for your first date. :-)

[Joe L.]

Re: '67 Gas Cap

Okay, so can I assume that the "sealed" cap was used beginning with MY 1970 in conjunction with the tank that has the added pressure/vacuum relief valve?

Duke

Duke-----



Yes. Actually, though, the pressure-vacuum valve was added in late 1969. However, all 1969's were originally equipped with the 64-69 style vented cap.

[Leif A.]

Re: '67 Gas Cap

Refering back to my original post, in determining that i had a replacement tank with a build in pressure-vacuum valve it was determined that i should should use the non-vented cap that i showed in the picture. Others stated that I could use a "correct" for '67 vented cap with no adverse issues. I just read John Hinckley's article on fuel vaport odors on C1 Corvettes wherein he states that by using an incorrect cap can result in fuel starvation on sharp right turns. http://www.lbfun.com/warehouse/tech_...hnHinckley.pdf

I had replaced the non-vented cap on my car with a "correct" vented cap the other day and went for a ride yesterday and had to make a sharp, hard right had turn, as i almost missed a street i was supposed to turn on. As i did so, the car died suddenly. I was able to restart the car and continue on with no further incident. Related?? John, I hope you're out there and will respond along with others. By the way, all new wiring harnesses, all connections tights, no wires shorting out under shielding or any of the other usual suspects.

Thanks in advance for input.

[Joe L.]

Re: '67 Gas Cap

Refering back to my original post, in determining that i had a replacement tank with a build in pressure-vacuum valve it was determined that i should should use the non-vented cap that i showed in the picture. Others stated that I could use a "correct" for '67 vented cap with no adverse issues. I just read John Hinckley's article on fuel vaport odors on C1 Corvettes wherein he states that by using an incorrect cap can result in fuel starvation on sharp right turns. http://www.lbfun.com/warehouse/tech_...hnHinckley.pdf

I had replaced the non-vented cap on my car with a "correct" vented cap the other day and went for a ride yesterday and had to make a sharp, hard right had turn, as i almost missed a street i was supposed to turn on. As i did so, the car died suddenly. I was able to restart the car and continue on with no further incident. Related?? John, I hope you're out there and will respond along with others. By the way, all new wiring harnesses, all connections tights, no wires shorting out under shielding or any of the other usual suspects.

Thanks in advance for input.

Leif------

Late 1969 Corvettes, including mine, all had fuel tanks with the integral pressure-vacuum valve. However, all 1969's were also equipped with a vented fuel cap, including mine. In 150,000 miles I NEVER had any problems such as you described. I'm sure I must have made at least a few sharp right turns in that time.

In any event, I would suggest that you use the original vented cap only for judging.

[John H.]

Re: '67 Gas Cap

Refering back to my original post, in determining that i had a replacement tank with a build in pressure-vacuum valve it was determined that i should should use the non-vented cap that i showed in the picture. Others stated that I could use a "correct" for '67 vented cap with no adverse issues. I just read John Hinckley's article on fuel vaport odors on C1 Corvettes wherein he states that by using an incorrect cap can result in fuel starvation on sharp right turns. http://www.lbfun.com/warehouse/tech_...hnHinckley.pdf

I had replaced the non-vented cap on my car with a "correct" vented cap the other day and went for a ride yesterday and had to make a sharp, hard right had turn, as i almost missed a street i was supposed to turn on. As i did so, the car died suddenly. I was able to restart the car and continue on with no further incident. Related?? John, I hope you're out there and will respond along with others. By the way, all new wiring harnesses, all connections tights, no wires shorting out under shielding or any of the other usual suspects.

Thanks in advance for input.

Leif -

I don't think I stated that (stalling on hard right turns caused by gas caps) in the article on C1 fuel odors, although it's a known issue with several TSB's published with Carter WCFB carburetors; at any rate, it has nothing to do with the type of gas cap - it's an internal carburetor issue.

C1's after mid-'57 all use NON-VENTED gas caps. Midyears all use VENTED caps with integral vacuum/pressure valves.

[Leif A.]

Re: '67 Gas Cap

Thanks, Gentlemen. I recently had the original Holley rebuilt. I will be taking it back looking for adjustments. Anything specifically i should ask them to look at? I'm assuming float levels?

[Stuart F.]

Re: '67 Gas Cap

Actually, 63's have a pure vented cap with one small hole. In 64 they started the cap with both pressure and vacuum valves. I bought and use one of them in my attempt to reduce the smell in my garage. It (the 64 and up cap) is the service replacement for the vented 63 cap. I reconditioned my 63 cap and put it on the shelf! Like so many 63 only parts, it's too valuable to leave on the car, specially at shows.

Stu Fox