Honda EB11000 Owner's Manual page 48

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.
A loose spark plug can overheat and damage the engine.
Overtightening the spark plug can damage the threads in the cylinder
head.
8. Reinstall the spark plug caps on the spark plugs securely.
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