MAINTENANCE AND REPAIR INSTRUCTIONS

Back Plate

 

 

Tabs

 

 

 

 

 

 

 

 

 

 

Air

Filter

Locking

Tab

Fig. 30

 

 

 

Fig. 31

 

 

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. 33). 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 head 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 head 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:

Air Filter Cover

Air Filter

Fig. 32

Tab

 

plate (Fig. 31).

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

8.Swing the cover down until the tab on the air filter backplate snaps into place in the slot on the air filter cover (Fig. 32).

•the engine will not idle

•the engine hesitates or stalls on acceleration

•there is a loss of engine power

Have the carburetor serviced 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

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

View Of The Rear Engine Cover

Remove

Remove

Screws

Screws

IDLE SPEED ADJUSTMENT

The idle speed of the engine is adjustable. An idle adjustment screw is between the air filter cover and the engine starter housing (Fig. 33).

NOTE: Careless adjustments can seriously damage your unit. Aside from the idle speed, only a Sears or other qualified service dealer should make carburetor

Idle Adjustment Screw

Fig. 34

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. 34).

adjustments.

1. Check Fuel

Fig. 33

2.

Disconnect the spark plug wire.

3.

Clean dirt from around the spark

 

plug. Remove the spark plug from

Rocker

Arm

Cover

Old fuel is usually the reason for idle speed problems. Drain and

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

refill the tank with fresh fuel prior to making any adjustments. Refer to Oil and Fuel Information.

2. 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. This is often mistaken for

the cylinder head by turning a 5/8

in. socket counterclockwise.

4. Remove the engine cover (Fig.

34).

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. 35). Remove

the rocker arm cover and gasket.

Spark

Plug

Hole

Fig. 35

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

an out of adjustment idle. Check the condition of the air filter before adjusting the idle speed screw. Refer to Air Filter Maintenance.

3. Adjust Idle Speed Screw

If, after checking the fuel and cleaning the air filter, the engine still

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. 36)

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

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. 36 & 37). Measure both the intake and exhaust valves.

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