1979 Models

Remove air cleaner and check all sensing tubes for correct routing or damage. Be sure dashpot does not keep throttle lever from returning to idle stop. Quickly operate throttle lever fully and make sure dashpot extends quickly.
Release throttle lever and make sure lever returns slowly to idle position after it has touched dashpot rod. Connect a tachometer to engine and warm to normal operating temperature. Be sure engine operates at specified idle speed.
Disconnect vacuum sensing tube from dashpot diaphragm and operate throttle lever until it is away from dashpot rod. Close vacuum inlet to dashpot diaphragm with finger.
Release throttle lever and check engine speed at which dashpot rod stops moving after it has been pushed in by throttle lever. Engine speed should be 1650-1850 RPM. If not, loosen lock nut and rotate dashpot diaphragm to obtain specified engine speed. Tighten lock nut.