Two thoughts...either the vent hose is leaking, which is directly above the ds muffler, OR....the tank has a rust hole in it. If you take the front tank brace off, you'll know real quick if it is a rust issue. But I would first look up towards the vent tube at the top, ds of the tank, about midway front/back and see if the hose is deteriorated....
If it only leaks when the tank is 3/4 or more full, it is the vent hose/tube. If it leaks no matter how much fuel is in it...it's prolly a rust hole...
If you have it mostly drained, you can take a bright light and look down into the tank from the filler, and usually get a good look at the bottom of the tank. If you see any funk standing at the very front edge of the tank, it's prolly rust. Had that problem on the '74. Tried JB Weld on it a couple of times, but it was just too much....I wound up buying a repro tank from Quanta.
|UPDATED|12/20/2013 3:03:58 PM (AZT)|/UPDATED|
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