MAINTENANCE AND REPAIR INSTRUCTIONS

CARBURETOR ADJUSTMENT

The idle speed of the engine is adjustable through the air filter/muffler cover (Fig. 43).

NOTE: Careless adjustments can seriously damage your unit. An authorized service dealer should make carburetor adjustments.

Check Fuel Mixture

Old and/or improperly mixed fuel is usually the reason for improper unit performance. Drain and refill the tank with fresh, properly-mixed fuel prior to making any adjustments. Refer to Oil and Fuel Information.

Clean Air Filter

The condition of the air filter is important to the operation of the unit. A dirty air filter will restrict air flow and change the air/fuel mixture. This is often mistaken for an out of adjustment carburetor. Check the condition of the air filter before adjusting the idle speed screw. Refer to Air Filter Maintenance.

Adjust Idle Speed Screw

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. Refer to Starting/Stopping Instructions.

WARNING: The cutting attachment may be spinning during idle speed adjustments. Wear protective clothing and observe all safety instructions to prevent serious personal injury.

2.Release the throttle trigger and let the engine idle. If the engine stops, insert a small phillips or flat blade screwdriver into the hole in the air filter/muffler cover (Fig. 43). Turn the idle speed screw in, clockwise, 1/8 of a turn at a time (as needed) until the engine idles smoothly.

Idle Speed Screw

Fig. 43

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 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.

WARNING: To prevent serious personal injury, make sure the cutting attachment has stopped rotating before you turn it off and set it down.

REPLACING THE SPARK PLUG

Use a Champion RDJ7Y spark plug, or equivalent. The correct air gap is 0.020 inch (0.5 mm). Remove the plug after every 25 hours of operation and check its condition.

1.Stop the engine and allow it to cool. Grasp the plug wire firmly and pull it from the spark plug.

2.Clean around the spark plug. Remove the spark plug from the cylinder head by turning a 5/8-inch socket counterclockwise.

3.Replace a cracked, fouled or dirty spark plug. Set the air gap at 0.020 in. (0.5 mm) using a feeler gauge (Fig. 44).

CAUTION: Do not sand blast, scrape or clean electrodes. Grit in the engine could damage the cylinder.

4.Install a correctly-gapped spark plug in the cylinder head. Tighten by turning the 5/8-inch socket clockwise until snug.

If using a torque wrench torque to:

110-120 in.•lb. (12.3-13.5 N•m) Do not over tighten.

0.020 in.

(0.5 mm)

Fig. 44

20