those distributors get dry and rusty around the upper shaft and advance won't work smooth and even advancing/retarding-----and q jets get build up of crud around jets/metering rods and idle passages------


do the work of replacing the rubber components before the carb clean/rebuild or you will just get more up there into your freshly cleaned carb and it ll clog again-also when working on something old--takes about 3 fuel filter changes before you get er done------