2006 Johnson SD 30 HP 4 Stroke Outboards Service Manual, PN 5006592, Page 65Get this manual
MAINTENANCE IDLE SPEED
IDLE SPEED
IMPORTANT: Before synchronizing the throttle valves, check the link mechanism and the carburetor valves for smooth operationStart the engine and allow the engine to warm up to normal operating temperatureConnect tachometer to the engine in the following manner: Yellow lead wire to YellowBlack lead wire of the power pack Gray lead wire to the positive (+) terminal of 12V battery Black lead wire to the negative (-) terminal of 12V battery Set the pole selection switch in the tachometer to "12"
adjusting idle speed, make sure that the carburetor throttle valves are properly synchronizedRefer to "Synchronizing the Carburetor Throttle Valves" on page 56If the idle speed is out of specification, adjust the idle speed by rotating the idle adjusting screw onlyDO NOT rotate the throttle valve screws on the No.1 or No.2 carburetors