Gas tank over pressure?

[fullauto60]

Today my after market Duel tank w/2 filler necks was over flowing from the pri gas filler neck.
It started this mourning.
I drove to work backed the turd into spot and it sputterd and stalled. Not quick to start up but did,then put her in spot shut down and went inside. A friend 10 min later tells me there is a pretty big puddle under my truck. We go look and yup there is.
Tank history the PO did an aux tank mod and when i bought the turd i put gas in the pri tank and it leaked almost as quick as i put it in. So i used the seconed filler neck and it was fine. so thats what i use.
(flash to present) when i dove it home today and looked, it was pouring out of the pri tank filler neck in which i dont use. It was seeping out of the cap, big puddle.
What could cause this?
Oh and gas is not cheap,as we all know.
Rich

[ March 04, 2004, 06:53 PM: Message edited by: fullauto60 ]

[Don S]

..
fullauto60

... Gasoline has a tendency to expand quite a bit as its temperature rises.
The temperature of it in an under ground storage tank would be somewhere around 67 degrees F. The ambient outdoor temperature plus the heat in the pavement and the heat of the exhaust system can expand the gasoline enough to cause an over follow.

Have a good one ;) and CUL.. Don S..

[fullauto60]

My tank was half full. Plus i did not use that tank. It's like the gas went from one tank to the other and came out the cap.
The new tank is a box type tank. I don't know if there is a connection between them or not.
The temp was 42DegC when i left for work and 42degc when i arrived, 63deg c when whent home.
Could there be a vent problem?

[Don S]

Originally posted by fullauto60:
My tank was half full. Plus i did not use that tank. It's like the gas went from one tank to the other and came out the cap...
fullauto60:

... In that case there is probably a return fuel line close to the carburetor and that line is putting fuel into the tank that was overflowing. There should be a fuel fiter with three nipples close to the carburetor. The return line needs to be run to the good tank you are using. plug it up till you can run the line.

Have a good one ;) and CUL.. Don S..