Replacing the Spark Plug

Cmean Air Fimter

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

Adjust Idle Speed Screw

If, after checking the fue[ mixture and cieaning the air fiiter, the engine still[ will[ not idie, adjust the idie speed screw as foiiows:

1, Start the engine and bt it run at a high idle for a minute to warm up, Refer to Stardng/Sto,oping Instructions.

WARNmNG: The cutting attachment will spin

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 screwdriver into the hob in the air filter/muffler cover (Fig, 27). Turn the idle speed screw in, clockwise, 1/8 of a turn at a time (as needed) until the engine idles smoothly,

3, If the engine appears to be idling too fast, turn the

idle speed screw counterclockwise 1/8 of a turn at a time (as needed), to reduce idle speed,

Idle Speed Screw

Fig. 27

Checking the fuel mixture, cleaning the air filter, and adjusting the idle speed should solve most engine problems. If not and all of the following are true:

the engine wiii not idle

the engine hesitates or staiis on acceleration

there is a loss of engine power

Have the carburetor adjusted by an authorized service dealer.

To prevent serious personal injury,

make sure the cutting attachment has

pped rotating after you turn it off and fou set it down.

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

1.Stop the engine and aiiow it to cooi. 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 ram} using a feeler gauge (Fig. 28).

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.,ib. (12.3-13.5 N,m}

Do not over tighten.

Fig. 28