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23
Fig. 23
0.025 in.
(0.635 mm)
MAINTAINING THE SPARK PLUG
1. Stop the engine and allow it to cool. Grasp the spark plug boot
firmly and pull it from the spark plug.
2. Clean around the spark plug. Remove the spark plug from the
cylinder head with a 5/8-inch socket, turning counterclockwise.
3. Inspect the spark plug. If the spark plug is cracked, fouled or
dirty, replace it with replacement part
#753-06847, a Champion
RDJ7J or an equivalent spark plug.
4. Use a feeler gauge to set the air gap at
0.025 in. (0.635 mm)
(Fig. 23).
5. 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.
6. Reattach the spark plug boot.
WARNING:
Do not sand blast, scrape or clean spark plug
electrodes. Grit in the engine could damage the cylinder.
ADJUSTING THE IDLE SPEED
If the engine will not idle properly:
1. Start the engine. Refer to Starting and Stopping.
2. Release the throttle control and let the engine idle.
NOTE: Make sure the choke lever is NOT engaged while adjusting
the idle speed.
• If the engine stops, increase the idle speed. Use a small
Phillips screwdriver to turn the idle speed screw clockwise,
1/8 of a turn at a time, until the engine idles smoothly (Fig. 22).
• If the saw chain spins when the engine idles, reduce the idle
speed. Turn the idle speed screw counterclockwise, 1/8 of a
turn at a time, until the saw chain stops moving (Fig. 22).
WARNING:
The saw chain may spin during idle speed
adjustments. Wear protective clothing and observe all
safety instructions to prevent serious personal injury.
MAINTAINING THE AIR FILTER
Failure to maintain the air filter can result in poor performance or
can cause permanent damage to the engine. Engine failure due to
improper air filter maintenance is not covered by the product warranty.
Cleaning the Air Filter
1. Open the air filter cover: Hook your fingers behind the cover tab.
To unlock the air filter cover, pull it to the left and away from the
engine. This may require a firm pull. Swing the air filter cover to
the right (Fig. 21).
2. Remove the air filter from inside the air filter cover (Fig. 21).
3. Wash the air filter in detergent and water. Rinse the air filter
thoroughly and allow it to dry.
4. Lightly coat the air filter with clean SAE 30 oil.
5. Squeeze the air filter to spread and remove excess oil.
6. Reinstall the air filter inside the air filter cover (Fig. 21).
NOTE: Operating the unit without the air filter and air filter cover will
VOID the warranty.
7. Close the air filter cover: swing the air filter cover to the left and
press it closed until the lock tab snaps into place (Fig. 21).
Fig. 21
Air Filter
Air Filter Cover
Lock Tab
Cover Tab
Fig. 22
Idle Speed Screw