Craftsman 316.74093 series Operator's Manual page 22

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. Unscrew the cover screw completely. Swing the air filter cover to
the right. Remove the air filter cover from the air filter housing
(Fig. 37).
2. Remove the air filter from the air filter housing (Fig. 37).
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 in the air filter housing (Fig. 37).
NOTE: Operating the unit without the air filter and air filter cover will
VOID the warranty.
7. Insert the tab on the air filter cover into the hole on the air filter
housing. Swing the air filter cover to the left. Push the air filter
cover back onto the air filter housing. Insert the cover screw into
the air filter cover. Tighten the cover screw to secure the air filter
cover (Fig. 37).
NOTE: Do not over tighten as this may strip the screw.
ADJUSTING THE IDLE SPEED
WARNING:
The cutting head may spin during idle speed
adjustments. Wear protective clothing and observe all
safety instructions to prevent serious personal injury.
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.
• 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. 38).
• If the cutting head 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 cutting head stops moving (Fig. 38).
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.
WARNING:
Do not sand blast, scrape or clean spark plug
electrodes. Grit in the engine could damage the cylinder.
3. Inspect the spark plug. If the spark plug is cracked, fouled or
dirty, replace it with replacement part #753-05784, a Champion
RDZ4H or an equivalent spark plug.
4. Use a feeler gauge to set the air gap at 0.025 in. (0.635 mm)
(Fig. 39).
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.
Hole
Air Filter
0.025 in.
(0.635 mm)
22
Tab
Air Filter
Housing
Fig. 37
Idle Speed Screw
Fig. 38
Fig. 39
Air Filter
Cover
Cover
Screw