17
Maintenance (continued)
If after checking the fuel mixture and cleaning the air
filter the engine still will not idle, adjust the idle speed
screw as follows.
1. Start the engine and let it run at a high idle for a
minute to warm up.
2. Release the throttle trigger and let the engine idle. If
the engine stops, insert a small phillips or flat blade
screwdriver into the screw next to the air filter
cover (Fig. 6-12). Turn the idle speed screw in,
clockwise, 1/8 of a turn at a time (as needed) until
the engine idles smoothly.
NOTE: The cutting attachment should not rotate
when the engine idles.
3. If the cutting attachment rotates when the engine
idles, turn the idle speed screw counterclockwise
1/8 of a turn at a time (as needed), to reduce idle
speed.
Checking the fuel mixture, cleaning the air filter, and
adjusting the idle speed screw should solve most
engine problems.
If not and:
• The engine will not idle,
• The engine hesitates or stalls on acceleration,
• There is a loss of engine power,
have the carburetor adjusted by an
authorized service dealer.
REPLACING THE SPARK PLUG
Use a Champion RCJ6Y spark plug (or equivalent). The
correct air gap is 0.025 inch (0.655 mm). Remove the
plug after every 50 hours of operation and check its
condition.
1. Stop the engine and allow it to cool. Grasp the plug
wire firmly and pull the cap from the spark plug.
2. Clean dirt from around the spark plug. Remove the
spark plug from the cylinder head by turning a 5/8
inch socket counterclockwise.
3. Replace cracked, fouled or dirty spark plug. Set the
air gap at 0.025 inch (0.655 mm) using a feeler
gauge (Fig. 6-13).
Do not sand blast, scrape, or clean electrodes.
Grit in the engine could damage the cylinder.
4. Install a correctly gaped spark plug in the cylinder
head. Tighten by turning the 5/8 inch socket clock-
wise until snug.
If using a torque wrench torque to;
110-120 in.•lb. (12.3-13.5 N•m).
Do not over tighten.
0.025 inch
(0.655 mm)
Fig. 6-13