CAUTION: running the engine with dirty, damaged or missing air cleaner element will cause the engine
to wear out prematurely.
SPARK PLUG MAINTENANCE
The spark plug is important for proper engine operation. A good spark plug should be intact, free of
deposits, and properly gapped. Refer to Recommended Maintenance Schedule. To inspect the spark plug:
1. Remove spark plug boot. Be careful not to tear insulation or wire.
2. Unscrew the spark plug from the engine using the spark plug wrench provided. There is limited space
for the wrench to turn. Use both rows of holes in the spark plug wrench to gain leverage to loosen the
plug.
3. Visually inspect the spark plug for cracks or excessive electrode wear. Replace as necessary.
4. Measure the plug gap with a wire gauge. The gap should be 0.7 to 0.8 mm (0.028-0.031 in).
5. If re-using the spark plug, use a wire brush to clean any dirt from around the spark plug base then
re-gap the spark plug.
6. Screw the spark plug back into the spark plug hole using the spark plug wrench. Do not over-tighten
spark plug. Recommended tightening of spark plug is ½ to ¾ of a turn after spark plug gasket contacts
spark plug hole. Reinstall the spark plug boot.
Maintenance Schedule
Item
Action
Blade
Inspect
Blade
Inspect
mounting bolt
Check
Engine oil
Change
Check
Air filter
Clean
Replace
Blade control
Check
operation
Check
Spark plug
Replace
Fuel tank
Clean
Flywheel brake
Check
pad
Valve
Check-adjust
clearance
Fuel line
Check
1. Service more frequently when used in dusty areas.
2. Change engine oil every 25 hours when used under heavy load or in high outside air temperatures.
Before
5 Hours of
each use
use or first
month
x
x
x
x
x
x
Check every 2 years and replace if necessary
First 25
50 hours of
hours of
use or
use
every 6
months
2
x
1
1
x
x
100 hours
150 hours
of use or
of use or
every year
every two
years
x
x
1
x
x
x
x
x
x
x
x