2004 SR Johnson 2-stroke 40, 50HP Service Manual, Page 70Get this manual
MAINTENANCE SYNCHRONIZATION AND LINKAGE
SYNCHRONIZATION AND LINKAGE
to 0.5 in(12 mm)Tighten idle speed screw locknutSee dimension "B
WARNING
To prevent accidental starting while servicing, twist and remove all spark plug leads
IMPORTANT: Synchronization and linkage procedures MUST be followed in sequence and be performed exactly as described to ensure consistent engine idling and smooth operation throughout the RPM range