Gas tank vapor return nipple follow up

[Chuck R.]

In my earlier post, I stated that I had the incorrect tank with no vapor return line nipple on the tank. Well now I do.

I took the tank to a reputable radiator/fuel tank repair vendor who at a cost of $72.00, washed out the tank, drilled it out, soldered in the new nipple, and then pressure checked it all for leaks.

I guess it's better than $100.00 (or more) for an un-known used tank or the $200 (or more) for a replacement.

Now all is well and I can now mount the #%$*&^%#!!! tank with confidence.

Chuck

[Joe L.]

Re: Gas tank vapor return nipple follow up

Chuck-----

This will work, but I probably wouldn't have done it this way. Here's why:

The tank that you have, if it has no fuel return line fitting is either a 63-E69 tank (if it has large "rounded" indentions on the ends; 68-E69 for only Holley-equipped cars) or a L69-70 tank originally used with Holley carb equipped cars (if it has "rectangularish" indentions on the ends). If it's an original or ealy SERVICE 63-E69 tank (SERVICE prior to about 1970), it will NOT have an integral pressure-vacuum valve on the tank. This valve is located on the top of the tank, about 6 or 8 inches to the left of the filler opening and appears like a quarter-sized, mostly flat, soldered-in piece.

The integral pressure-vacuum valve was added to Corvette tanks in very late 1969 (my September, 1969-built car was among the first to have it). It was also added to ALL 63+ GM SERVICE tanks about 1970. "Authentic" reproduction 1963-E69 tanks generally do not have the valve, though. Most aftermarket replacement tanks do, though.

This valve is A GOOD THING TO HAVE. Using it, you can use a non-vented gasoline cap. The combination of the pressure-vacuum valve and non-vented gasoline cap will significantly reduce the intrusion of gasoline vapors into the cockpit of the car, especially a problem with convertibles. That's why GM added the valves not only to PRODUCTION tanks after late 1969, but also to all 63-69 SERVICE tanks as well. For judging, you can always convert back to a "correct" vented fuel cap; it's really quite easy to do.

[Chuck R.]

Re: A couple or three things Joe

This tank was a replacement purchased around 1977 according to the dealer data stickers that was still attached to the tank.

Secondly, the DOES have the internal pressure vacuum valve.

This tank is definately a late 1969 style tank probably for 3x2 applications.

How were the Maine lobsters, still $4.99 a pound

Regards,

Chuck

[Joe L.]

Re: A couple or three things Joe

Chuck------

Oh, I assumed that you were trying to save an original 1968 tank. No original 1968 tank had the pressure-vacuum valve. However, after about 1970, ALL 63+ GM tanks had the valve (thru the 1974 moddel year) so that explains why this tank from 1977 had it. Like I say, it's good to have it. Keep in mind, though, that the valves can start leaking in time. When this happens, a new tank is necessary. Although a new valve could probably be soldered in, I don't think that these valves are available seperately.

I did get some lobsters for $4.99/LB. At restaurants I paid considerably more, though. I ended up "doing" 25 of them in the 2 weeks I was in the east; 4 of those I had with all my fellow Vetteheads at Carlisle.