3. Spark plug service I
Recommended spark plug: BMR4A (NGK)
WI 4MR-U (ND)
To ensure proper engine operation, the spark plug must be properly gap-
ped and free of deposits.
1. Remove the spark plug cap.
,.
-4
m
If the engine has been running, the muffler will be very hot. Be
careful not to touch the muffler.
2. Visually inspect the sp if the insulator is cracked or
chipped. Clean the spark plug with a wire brush if it is to be reused.
3. Measure the plug gap with a feeler gauge. The gap should be 0.6-0.7
mm (0.024-0.028 in). Correct as necessary by bending the side
electrode.
0.6-0.7 mm
(0.024~0.028 in)
4. Thread the plug in by hand to prevent cross-threading.
5. After seating it by hand, 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.
HWORTANT NOTlCE The spark plug must be securely tightened. An im-
properly tightened plug can become very hot and possibly damage the
engine. Never use a spark plug with an improper heart range.
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