Vent tube question 68 Barracuda

-

jagsdtc

jagsdtc
Joined
Nov 10, 2011
Messages
150
Reaction score
15
Location
Loganville, GA
I've always had to fill my tank slowly to avoid continual splashing back of the gasoline every gallon or less. And it's a pain to get get it full. I was told by someone it could be a clogged vent tube. I removed mine and found the top end had the flared bulb with a smaller hole than the tube.

Question 1) should air flow through the tube when I blow compressed air through it?
Question 2) Is there a check valve of some sort in the end?
Question 3? what would happen if I cut off the end so the opening is the size of the tube?

Thanks!
 
We need a bit more info.

When you are filling up, tell us about the fuel filler handle on the gas station (better yet a photo)

Question 1) should air flow through the tube when I blow compressed air through it?
Yes

Question 2) Is there a check valve of some sort in the end?
No


Question 3? what would happen if I cut off the end so the opening is the size of the tube?
The flare is there to keep the short hose from the fuel filler neck to the vet tube from slipping off.

Your filler neck should look like this
Screenshot_20210411-081000.png


Just inside your filler neck on the top of it there is a piece of metal welded in that creates the vent line to the tube. This is the end inside the gas tank, fuel goes in on one side and air goes out on the other. This tube end is rotated 90 deg in the photo
Screenshot_20210411-081830.png
 
Last edited:
The 1/4" tank vent HAS NOTHING TO DO with filling your tank, although it is important that it be open for proper tank venting while driving

"What vents" your tank during filling is the divider baffle shown in one of the photos above. This "encourages" fuel to run down the bottom side of the tube, while leaving an open air passage to the top.

We don't have the "Oregon style" fuel filler vapor boots on filler nozzles. This may be an issue as may be too high pressure at some pumps. Or your baffle may be damaged/ missing
 
I've always had to fill my tank slowly to avoid continual splashing back of the gasoline every gallon or less. And it's a pain to get get it full. I was told by someone it could be a clogged vent tube. I removed mine and found the top end had the flared bulb with a smaller hole than the tube.

Question 1) should air flow through the tube when I blow compressed air through it?
Question 2) Is there a check valve of some sort in the end?
Question 3? what would happen if I cut off the end so the opening is the size of the tube?

Thanks!

Its been a long time ago, but in 1968 I bought a brand new 68 form S 383 fastback , it did the same thing ! Really pissed me off .
Now I have one that I rebuilt and have 2 vents on it , it doesnt do it .
It is a vent situation and always has been .
 
-
Back
Top