I've been looking through the volumes of posts about this issue, and I'm not readily finding physical descriptions of which screw is which. Anybody know offhand? Anybody got any diagrams? Bueller? Right now, I have new plugs, wires, cap, rotor, but it's still rough at startup, and when I rev it high, It kicks out a cloud of fumes that makes my eyes water like a MF. I recently had the carb rebuilt, and I'm thinking it's time for an adjustment? How often does this bastard need rebuilt? Or is it just my timing?
There is only one 'idle' mixture adjust screw (in the base) next to the throttlle control arm. The other settings are for the solenoid positioner and idle stop. Sounds like the float is to high on hi speed testing. The rest of the settings are done with the understanding of what cold raised idle needs to be including choke requirements and 'after' the hot idle mixture has been made so it does not enter into the procedure. Do the cold adjustments on a cold engine as many times as you need to get it right. Pay attention to the fast idle cam screw setting for high idle and that this come off as the choke opens so the idle returns to your motor running setting for RPM. The procedures are is the books but without, you have to use logic based on what is supposed to happen as the motor warms up including the electric choke setting. In the procedure, you must account for the solenoid operation such that it closes the throttle when the ignition is shut down to prevent 'after-run'. The choke position at such a point that the electric operation pulls it open as the motor heats and the internal electric heat element also helps it open. And so it goes. It's a touchy and prolonged set of adjustments to get it about right but that was the state of the science back then. Today the computer controlled motors actually do all the same operations but with all electric controls from the computer that change setting according to operating conditions. They have cold high idle, sensed by warmup and a timer under certain conditions as well as the fuel injected is also controlled in place of a choke. So nothing has really changed in reguards to motor requirements. Good luck.
