1963 Corvette locking gas cap vented or non vented??

[Blk63Vette]

Hello

I wonder if there is someone out there will have the answer Im looking for...I bought a "original" locking gas cap for my Vette...I noticed it does NOT have a "hole" on the top (Chrome part) of the cap...However, underneath it has the GM numbers EE54-3-Z-75. This also have a "vent tube" on the inside of the cap..

I am wondering if this is a Vented cap? or a Non vented cap?

Totally confused! :bash

 

[67HEAVEN]

Blk63Vette,

Welcome to the

If the casting number inside is EE54-3-Z-75, then it was a GM Accessory Part #985919 -- Catalogue Group 3.028. The original manufacturer was EC Products.​

It was an across-the-counter Chevy dealer accessory and was vented.​

 

[Blk63Vette]

Hi Heaven 67 another question

Hi

Thanks for welcoming me to the forum...My question is this...Since this does NOT have a hole on the top (chrome part) it is NOT vented??

I have been told that since their is no hole at the top for vent it is Not vented is this true??? Can this ruin my gas tank ? Can it crush my gas tank like a pop can?

thanks
Pete

 

[67HEAVEN]

As I said above, it is vented. I've used one on my '67 for over 35 years and it hasn't imploded yet.

 

[Blk63Vette]

Hi

So is it posssible i have a GM non vented gas cap?

thanks

 

[JohnZ]

Hi

So is it posssible i have a GM non vented gas cap?

thanks

Could be - if it isn't vented, don't use it.

 

[66bluerdster]

I have the same question as Blk63Vette, does a locking cap need to have the "hole" on top to be vented?

The locking gas cap from Corvette Central is said to be vented but has no visible hole in the cap. Wondering if there is another way the cap is designed to vent itself.

Thanks.

http://www.parts123.com/parts123/yb...~S2AP0ZKWYI21610132150D~Z5Z5Z5~Z5Z5Z50000050B

 

[Red Vette]

As I said above, it is vented. I've used one on my '67 for over 35 years and it hasn't imploded yet.

I agree with 67 Heaven, I had the same locking chrome gas cap on my 66 for 14 years with no problem. For all I know, I may still have it with my old parts as it did not go with the car.
Barrett

 

[paul67]

As I said in another forum just use it and see if it works without creating vacuum within the tank.

 

[WayneC]

As I said in another forum just use it and see if it works without creating vacuum within the tank.

I agree.... even if it were non-vented it would be much more likely to just stop flowing gasoline to the carb than to damage your tank. Fill the tank and try it for a half-tank or so of gasoline, then listen for a very noticeable whoosh of sucking air as you twist the cap open, like opening a pop can you've gently shaken; no sound, no problem.

 

[alps66]

FWIW, I bought a new Challenger 340 in 1970. The first time I filled the tank, it only registered 3/4 full. I didn't think much about it. The next time, it only took a quarter of a tank, at which time I looked under the car, only to find that the gas tank had collapsed as the result of a venting problem. It took three months to get a replacement tank (my good friends at Mopar wouldn't pull a tank off the production line of this new hot selling model to replace mine). I replaced the cap but was relegated to driving a brand new car that got nine miles to the gallon with a tank that held four. Needless to say, I did a lot of 'filling' up. That was just one of the countless problems I had with that car which forced me to get rid of it within a year (the worst problem was a drivetrain alignment issue that ate clutches - four in a 11000 miles). Never owned a Chrysler product since, but I sure scratch my head at the prices those pieces of (fill in the blank) are bringing today.

 

[muddywaters]

In a pinch, Disconnect and block all lines to the tank except fill, figure out a way to introduce compressed air into the tank, dont over do it, I said in a pinch, it would get you by until new tanks arrives. It's done on motorcycles all the time..............Now , I know there's other way's to pressurize a tank, You could put cap in place if it's non-vented and pressurize thru vent, what ever works.............

 

[muddywaters]

Yeah alps66, I remenber those Mopars, they where everywhere, a friend had a 340 six-pak set up, pistol grip 4spd, those where the day's, gas 29.9/gal.........