17
ADJUSTING THE IDLE SPEED
NOTE:
Careless adjustments can seriously damage the unit. An
authorized service dealer should make carburetor adjustments.
If, after checking the fuel and cleaning the air filter, the engine still
will not idle, adjust the idle speed screw as follows:
1. Start the engine. Refer to
Starting and Stopping
.
2. Release the throttle control and let the engine idle.
• If the engine stops, use a small Phillips screwdriver to turn the
idle speed screw clockwise, 1/8 of a turn at a time (as needed)
until the engine idles smoothly (Fig. 27).
• If the engine idles too quickly, turn the idle speed screw
counterclockwise, 1/8 of a turn at a time (as needed) to reduce
the idle speed (Fig. 27).
NOTE:
The cutting head should not spin when the engine idles. If it
does, reduce the idle speed until the cutting head stops moving.
Checking the fuel, cleaning the air filter, and adjusting the idle speed
should solve most engine problems. If not, and any of the following
conditions are true, take the unit to an authorized service dealer:
•
the engine will not idle
•
the engine hesitates or stalls on acceleration
•
there is a loss of engine power
WARNING:
The cutting head may spin during idle speed
adjustments. Wear protective clothing and observe all
safety instructions to prevent serious personal injury.
Fig. 27
Idle Speed Screw
Fig. 29
0.025 in.
(0.635 mm)
MAINTAINING THE SPARK PLUG
1. Stop the engine and allow it to cool.
2. Remove the six (6) screws from the engine cover with a flat-head
screwdriver or T-25 Torx screwdriver (Fig. 28). 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.
5. 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.
6. Use a feeler gauge to set the air gap at
0.025 in. (0.635 mm)
(Fig. 29).
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.
WARNING:
Do not sand blast, scrape or clean spark plug
electrodes. Grit in the engine could damage the cylinder.
Fig. 28
Screws
Screws
