●Visually inspect the spark plug. Discard it if the insulator is cracked chipped.
●Measure the plug gap with a feeler gauge. The gap should be 0.7-0.8mm
(0.028-0.031in). Correct as necessary by bending the side electrode.
●Attach the plug washer. Thread the plug in by hand to prevent cross-threading.
●When mounting a new spark plug, you should screw 1/2 more thread with the wrench
after the washer is compressed. If you are mounting an old one, you should only screw
1/8 – 1/4 more thread.
CAUTION:
The spark plug must be securely tightened. An improperly tightened plug can become
very hot and possibly damage the engine. Never use a spark plug with an improper
heat range.
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