Idle Microswitch
Remove carburetor. Turn fast idle cam counterclockwise and insert a suitable pin into holes in cam and bracket locking cam in place. Connect ohmmeter to microswitch connector. With throttle valve in idle position, ohmmeter should indicate no resistance. With throttle valve opened 1/4 to 1/2 of the way, the ohmmeter should jump from no resistance to infinity. See Fig 1 .