1988 Johnson Evinrude CC 60 thru 75 outboards Service Manual, Page 64Get this manual
Throttle Valve Synchronization INotel With the engine idling in NEUTRAL, if loosening the carburetor lever adjustment screws results in better idle, improper synchronization of the throttle valves is indicated At idle, the throttle valves in all carburetors must be completely closedIf the carburetor linkage is misadjusted so one carburetor throttle plate is slightly open, it will result in poor quality idle1Remove the air silencer cover to observe the throttle valve actionf3l2Loosen the throttle cam follower screwPush the throttle cam follower away from the throttle camThe throttle cam follower must not touch the throttle cam during this procedure f413
Loosen upper and lower carburetor lever adjusting screws which allows the return springs on the throttle shafts to fully close the throttle valves
EJ closed to be certain the throttle valves are closedPress
upward on tabs of the adjusting links to remove backlashTighten the adjusting screwsAdjust the lower carburetor linkage first, then the upper linkageMove the cam follower and check that the throttle shafts start to rotate at the same timeIdle Speed Adjustment f3lI Note Before follower engine speed, be sure throttle cam not touching throttle cam