I posted this on NCRS and figured I would share with you.
I was out in my 72 on Sunday and filled the tank before stopping for 1.5 hours. When I came out I found gas dripping out behind the LF tire area. I was confused, knowing the gas line from the tank to the fuel pump is on the RH side.
So I took a look underneath and saw the original charcoal tank had gas dripping out pretty good, about a qt or so into a plastic container we placed under it. I forgot about the gas vapor line from the top L H side of the gas tank. There is a check valve there and a hose running down the LH frame rail to the top of the charcoal tank under the LH fender.
The guys on NCRS confirmed what I suspected, I overfilled the tank, the check valve didn't work as it should and flooded the charcoal tank. Joe Lucia also confirmed the filler necks on the 70-74's are deeper to prevent over filling unless you do what I did and filled it up too much.
I let it drip, started up and it stopped, drove 15 miles home without a problem and it was fine.
I've owned this car since 1979 and never had this happen before so the check valve must have just failed the other day.
Just thought I'd pass it along in case anyone else has this issue.
Gary
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