Honda HSS622 Owner's Manual page 53

Spark plug—cleaning and adjustment
The spark plug must be periodically cleaned and adjusted to provide
reliable ignition.
INTERVAL AT WHICH THE SPARK PLUG MUST BE CLEANED:
Every year, before operation.
CLEANING PROCEDURE:
If the engine has been running, the muffler will be very hot. Be careful
not to touch the muffler while it is hot.
To ensure proper engine operation, the spark plug must be properly
gapped and free of deposits.
1.Remove the spark plug cap.
2.Clean any dirt from around the spark plug base.
3.Use the wrench supplied in the tool kit to remove the spark plug.
4.Visually inspect the spark plug. Discard the spark plug if there is
apparent wear, or if the insulator is cracked or chipped. Clean the
spark plug with a wire brush if it is to be reused.
SPARK PLUG WRENCH
50
SPARK PLUG CAP