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MAINTENANCE AND LUBRICATION
Spark Plugs
1. Normal
The normal insulator tip is gray, t an or light brown. There will be few combustion
deposits. The electrodes are not burned or eroded. This indicates the proper type and heat
range for the engine and the service.
NOTE: The tip should not be white. A white insulator tip indicates overheating, caused
by use of an improper spark plug or incorrect carburetion adjustments.
2. W et Fouled
The wet fouled insulator tip is black. A damp oil film covers the firing end. There may be
a carbon layer over t he entire nose. Generally, the el ectrodes are not worn. General causes
of fouling are excessive oil, use of non-recommended oil, improper use of the choke, or
incorrect carburetion adjustments.