Craftsman 536.772321 Operator's Manual page 7

Repair / Adjustments Safety
After striking a foreign object, stop the engine.
Remove the wire from the spark plug, and keep the
wire away from the plug to prevent accidental
starting. Thoroughly inspect the Edger for any
damage, and repair the damage before restarting
and operating.
If Edger should start to vibrate abnormally, stop
engine and check immediately for the cause.
Vibration is generally a warning of trouble.
• Stop the engine whenever you leave the operating
position. Also, disconnect the spark plug wire
before unclogging the blade and when making any
repairs, adjustments, or inspections.
• When cleaning, repairing, or inspecting, shut off the
engine and make certain all moving parts have
stopped.
• Never attempt to make any adjustments while the
engine is running.