Honda EM600 Owner's Manual page 21

5. Attach the plug washer. Thread the plug in by hand to prevent cross-
threading.
6. Tighten a new spark plug l/2 turn with the wrench to compress the washer.
If you are reusing a plug, it should only take l/8-1/4 turn after the plug
seats.
CAUTION:
l
The spark plug must be securely tightened. An improperly tightened plug
can become very hot and possibly damage the generator.
l
Never use a spark plug with an improper heat range.
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