this is what i got . dart singleplane seems to collect and oily fuel mix at the base of the two runners are seperated at tne flange of the intake .? it appears its comming from the carb and flowing down the little crease from the casing to end up at the base by the intake runner plate . what this from . why oily . from the intake . . best i can explain without pics sorry .. kind of vague i know . thanks rob

Is the oily substance coming from your pcv line where it's routed into the back of the intake just under your carb ? That would explain it .