Craftsman WEEDWACKER INCREDI-PULL 316.711930 Operator's Manual page 19

MAINTAINING THE SPARK PLUG
1. Stop the engine and allow it to cool.
2. Remove the 6 screws from the engine cover with a flat-head
screwdriver or T-25 Torx screwdriver (Fig. 23). Remove the
engine cover.
3. Grasp the spark plug boot firmly and pull it from the spark plug.
4. Clean around the spark plug. Remove the spark plug from the
cylinder head with a 5/8-inch socket, turning counterclockwise.
WARNING:
Do not sand blast, scrape or clean spark plug
electrodes. Grit in the engine could damage the cylinder.
5. Inspect the spark plug. If the spark plug is cracked, fouled or
dirty, replace it with a replacement part #753-05784, a
Champion RDZ4H or an equivalent spark plug.
6. Use a feeler gauge to set the air gap at 0.025 in. (0.635 mm)
(Fig. 27).
7. Install the spark plug in the cylinder head. Tighten the spark plug
with a 5/8-inch socket, turning it clockwise until snug.
NOTE: If using a torque wrench, torque to:
110-120 in.•lb. (12.3-13.5 N•m). Do not over tighten.
8. Reattach the spark plug boot.
9. Reinstall the engine cover. Check the alignment of the engine
cover before tightening the screws. Tighten the screws.
0.025 in.
(0.635 mm)
19
Fig. 27