Well problem solved. There was something truly nasty dissolved in the gas. There was rust for sure, no surprise, but there was weird sticky crap that turned the gas dark orange and left a film on everything like dried pancake syrup. Maybe it was sugar! It turned the rust in the bottom of the tank into a shiny black crust, that crumbled into red dust. Weird. I think it was caused by a relatively small amount of dissolved goo that glued the rust into a matrix. http://wps.com/AMC/1963-Rambler-American/Rebuilt-head/ At least I found the problem. It's obvious in hindsight... I had been assuming that the shiny goo on the valve tulips ran down the stems from my squirting Aerokroil on them while running, but that's silly, as it's obviously way too much stuff for that. I wish I had paid more attention. I did some half-assed chromatography with some cardboard strips, it actually worked. I may try this on other car goos, like antifreeze, and see how much oil or whatever is in there. It's easy as hell. _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://www.amc-list.com/mailman/listinfo/amc-list