Gas Tank Filler Necks: Anatomy/Physiology?

[STF455]

[ QUOTE ]

I completely emptied the tank. Let it sit for a day. Ran a garden hose in it until it overflowed for about 5 min. Emptied the water. Let it set til the afternoon. Set the tank up on a work bench, cleaned the spot really well, went to solder the penny on, and as soon as I hit the hole with an open flame.... BOOM.

Fortunately, it only slightly balloned the tank.

[/ QUOTE ]

I did that too, attempting to re-solder a leaking filler neck, assuming that all that water would surely flush all the fumes out. WRONG!

My friend Don was observing (from a distance) and kept saying "I wouldn't do that if I was you". One touch with the torch and the filler neck launched past my head; the fireball burnt off my eyebrows and singed most of the hair on my head and arms. Don finally quit laughing long enough to ask if I was OK, then said "that's one way to make sure the fumes are out".

[YENKO DEUCE REGISTRY]

Sorry, was just passing through, should have typed more....

I could see in one of the pics that the neck was curved to the right, and enters the tank on an angle. That style began in '71, which also features the EEC option - hence the need to change the filler neck so the 'vented' cap would fit.

The '70 version is a straight neck that goes directly into the tank, and has the shallower lip for the vented cap = non-EEC.

[x Baldwin Motion]

[ QUOTE ]
Glad it wasn't [ QUOTE ]
Fire all of yer gas tanks and...
explode into space!

[/ QUOTE ]

Looks great Sam!


[/ QUOTE ]


He's just kidding about that being a 1971 tank, right ?

woops

[Nova Research Project]

The Normal Observable Practice is the 1970 year had three different tanks.

The 1970 straight vented (Commonly called the 68-69 tank) Quanta Part #46A:


The 1970 angled vented. Quanta Part #46D:


The 1970 EEC non vented Quanta Part #46E:


Then in there is the 1971-1972 w/o EEC. Quanta Part#46C:


Note the last three all look the same. Not having the drawings the only difference is in the gas cap fitting.

It pays to make sure you have the right part number tank.

The 1970 straight vented was in my January car so was used past then. Not sure how far. However my July car has angled vented. Hard to track with so many replaced of the years.

Greg

[mockingbird812]

Greg - good stuff. I appreciate your detailed research on all things Nova. Do you have any idea what the angled neck mod accomplished? Was this a design improvement/safety change/etc?

Thanks

[Nova Research Project]

Sam,

You are welcome, happy to help. I do not know why they changed. I would be great to see the engineering change documents. I am not sure they are still available under new GM.

Greg

[JRSully]

My guess on the angled neck, Chevy realized it had a design flaw in the 68 and up Nova tank. Upon nailing it, the fuel flows right up (and sometimes out) of the neck due to it being so "flat" and not angled up. And good luck trying to fill the tank to capacity, tough to do with that neck. I think the angle may cut the straight shot up the tube.? My .02

[YENKO DEUCE REGISTRY]

I think the straight neck '70 version was used for the complete year, and the '70 EEC version was only used in CA.

[x Baldwin Motion]

I need to replace the tank in Mike's 69 Nova, I don't really care about it being correct, I prefer safer. Will the bent neck style 70 tank fit right in there?

(and where is "Quanta" located) Thanks.

or, I could always launch my tank out to Sam for a quick repair!!

[YENKO DEUCE REGISTRY]

Either style tank will fit perfectly. Just be aware that the if you use an EEC tank with the non-vented cap you should then use the sending unit with the extra outlets for the EEC - essentially the "vents". Otherwise, there is a risk of sucking in the tank.