i was going to be slick and plug the sloppy vent whistles on the carb where they meet the block so i thought i would use jb weld, like you quoted above.
everything clean and everything, or so i thought, the stuff looked like it released from the metal and i had no problem taking the whistles out and cleaning the metal surfaces or plastic whistles. maybe the surfaces weren't rough enough. i could probably cut the jb weld with a knife. i use a fuel additive so maybe that did something.
i used some on fittings inside the block also
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