MAINTENANCE AND REPAIR INSTRUCTIONS

3. Adjust Idle Speed Screw

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

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 and let it run at a high idle for a minute to warm up. Refer to Starting/Stopping Instructions.

2.Release the throttle trigger and let the engine idle. If the engine stops, insert a small phillips screwdriver in between the Air Filter Cover and the Engine Cover (Fig. 30). 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), until the attachment stops turning.

Checking the fuel, 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 will not idle

the engine hesitates or stalls on acceleration

there is a loss of engine power

Have the carburetor adjusted by a Sears or other qualified service dealer.

ROCKER ARM CLEARANCE

This requires disassembly of the engine. If you feel unsure or unqualified to perform this, take the unit to a Sears or other qualified service dealer

5.Clean dirt from around the rocker arm cover. Remove the screw holding the rocker arm cover with a large flat blade screwdriver or Torx T-25 bit (Fig. 32). Remove the rocker arm cover and gasket.

6.Pull the starter rope slowly to bring the piston to the top of its travel, (known as top dead center). Check that:

The piston is at the top of its travel. Look in the spark plug hole to view the piston (Fig. 33)

Both rocker arms move freely, and both valves are closed.

Rocker Arms

INTAKE

 

Feeler Gauge

Spark Plug

Hole

Fig. 33

Rocker

Arm

Cover

Spark

Plug

Hole

Fig. 32

Adjusting Nuts

EXHAUST

NOTE: Inspect the valve to rocker arm clearance with a feeler gauge after the first 10 hours of operation and every 25 hours of operation.

The engine must be cold when checking or adjusting the valve clearance.

This task should be performed inside, in a clean, dust free area.

1.Remove the six (6) screws on the back of the engine cover with a Flat-head or T-25 Torx screwdriver (Fig. 31).

View Of The Rear Engine Cover

Remove

Remove

Screws

Screws

Fig. 31

2.Disconnect the spark plug wire.

3.Clean dirt from around the spark plug. Remove the spark plug from the cylinder head by turning a 5/8 in. socket counterclockwise.

4.Remove the engine cover (Fig. 31).

If these statements are not true, repeat step 6.

7.Slide the feeler gauge between the rocker arm and the top of each valve stem. Measure the clearance between the valve stem and rocker arm (Fig. 34). Measure both the intake and exhaust valves.

Adjusting Nut

Rocker Arm

.003–.006 in. (.076–.152 mm)

Feeler Gauge

Valve Stem

Fig. 34

The recommended clearance for both intake and exhaust is .003 –

.006 in. (.076 – 0.152 mm). Use a standard automotive .005 in. (0.127 mm) feeler gauge. The feeler gauge should slide between the rocker arm and valve stem with a slight amount of resistance, without binding. See Figures 33 and 34.

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