My 1986 d-150 hesitates on take off, then sometimes picks up and goes with no problem, sometimes it stalls and is hard to start. I have a 318 (40 degrees over) with about 45,000 rebuilt miles. the truck just has the basics on it. (electric dist.- 2 wires) electric choke, etc. I have redone the adjustments over and over again to no avail. I can get a rebuild kit for the carb, but as many times as ive had it open and gone thru everything, im not sure if it needs it. any help would be appreciated since it is the only vehicle i use every day. thanks.