Shindaiwa EB8520RT Operator's Manual page 26

Maintenance and care
Check spark plug
a: 0.6 mm
139/150-Hour maintenance
Tools required: Spark plug wrench, Feeler gauge
Parts required: Spark plug
IMPORTANT
Never allow dirt or debris to enter the cylinder bore. Before
removing the spark plug, thoroughly clean the spark plug
and cylinder head area.
Use only NGK CMR5H or equivalent type plug of the correct
heat range otherwise severe engine damage may occur.
1. Remove and clean the spark plug.
2. Check plug gap. Correct gap is 0.6 mm.
3. Inspect electrode for wear.
4. Inspect insulator for oil or other deposits.
5. Replace plug if needed and tighten to 16.7 N·m - 18.6 N·m
(170 kgf·cm to 190 kgf·cm).
Maintenance after first 139-hours, then every 150-hours
thereafter
Combustion chamber should be decarbonized, and the valve
clearance should be adjusted. It is highly recommended that
this is done by a Shindaiwa-trained service technician.
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