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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 Before
each
5 Hours of
use or first
First 25
hours
50 hours of
use or every
100 hours
of use or
150 hours of
use or every
Blade
mounting
Inspect x
Engine oil
Change x x
2
x x
Air filter
Clean x
1
x
1
x
1
Blade control
operation
Check x x
Spark plug
Flywheel
Check x
Valve
Check-
x
2.Change engine oil every 25 hours when used under heavy load or in high outside air temperatures.