Ive used something called Marine-tex that was pretty effiective too..sealed the bottom of a tank with it..
Years ago I saw this product covered in a tech article, or maybe on one of those hot rod TV shows, that was aluminum filler rod that could be heated with something like Mapgas and melted into holes and voids. They showed it working on an intake manifold and was used to fill a stripped hole which was then drilled and retapped. Anyone remember this product? Looked pretty useful to me.
I used it on an aluminium trials bike tank, didn't want to weld it cause it would spoil the original paint, never had a problem.
Jon and the O/P Phil, and of course anyone else following, have you guy's tried this? look here, www.alumiweld.com, works on intakes and even in salt water enviroments. I have and I like using it, but never tried it on a carb body. All the best, TR
FWIW, I filled a couple pinholes on an old Superglide tank with the resin from a fiberglass repair kit. Let it harden for 24 hours, and had no problems with it whatsoever, even painted it after a year. It was on the top of the tank though, so it wasn't like it was always submerged in gasoline. I wouldn't hesitate to do it again, and it felt much safer than welding or brazing it.
I actually repaired a water jacket crack in an FE block. Removed the core plug next to the crack, cleaned as much as possible, applied JB Weld to the inside and left it overnight. It lasted long enough to drive 1800 miles from Ok, to Northern Ca. Never tried it for gas leaks,... 4TTRUK
I took the epoxy off and on the one side it was hard to see any kind of hole. The other it was a hole about the size of a pin head on the back side of where the metering block mounts. I even used a magnifying glass to check these areas out. I went ahead with the JB Weld on both sides of the carb and it's setting up as we speak. This carb won't be used for a while just gathering parts for the big block in my truck, it will have plenty of time to cure. I might pull the carb on the current set up and see how this carb does to make sure it's ok when I get caught up on the Henry J. Thanks for all the replies and advice fellas.
Oh yeah, I really wish the seller would have made mention of this and I wouldn't be where I'm at. But that's the chance you take buying off of there.