Honda EB11000 Owner's Manual page 49

6. Check that the spark plug washers are in good condition, and thread
the spark plugs in by hand to prevent cross-threading.
7. After the spark plugs are seated, tighten with a spark plug wrench to
compress the washer.
If installing a new spark plug, tighten 1/2 turn after the spark plug
seats to compress the washer. If reinstalling a used spark plug,
tighten 1/8-1/4 turn after the spark plug seats to compress the
washer.
The spark plug must be securely tightened. An improperly tightened
spark plug can become very hot and could damage the engine.
Never use spark plugs which have an improper heat range. Use only
the recommended spark plugs
or
equivalent.
8.
Reinstall the spark plug caps on the spark plugs securely.
47