1990 Johnson Evinrude "ES" 60 thru 70 Service Manual, P/N 507873, Page 163Get this manual
& General Safety Warnings To avoid accidental starting of engine while servicing, take adequate precautions to disarm the ignition system: aConnect engine wiring harness to boat wiring harness with keyswitch in OFF positionbTwist and remove all spark plug leads from spark plugscDisconnect the battery cables at the battery To prevent possible fire or explosion under the engine cover after servicing: aCheck entire fuel system for leaksbMake sure all electrical and ignition leads are routed and clamped in their original positions away from rotating engine parts Replace any locking fastener (locknut or patch screw) if its locking feature becomes weakDefinite resistance to tightening must be felt when reusing locking fastenerIf replacement is indicated, use only authorized replacement or equivalent To prevent possible injury, test the engine's entire shift system and start-in-neutral protection before returning engine to the customerU