hey everyone im syncying my carbs at the moment and its hooked up to the carb sync tool and when i twist the throttle cylinders 1,2,3 all go up in vaccumm but number 4 goes down first then goes up, any idea what that could be?
Thats a good one. all I can think of is maybe a spring isn't in quite right. Take that cap off the carby & check inside, check the diaphram isn't split or not seated in it's groove or pinched or something.