Polaris 2007 ATV Sawtooth - Manual (Page 80)

77
MAINTENANCE
Spark Plugs
Spark Plug Condition
Normal Plug
The normal insulator tip is gray, tan 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.
Wet Fouled Plug
The wet fouled insulator tip is black. A damp oil film covers the firing
end. There may be a carbon layer over the entire nose. Generally, the
electrodes are not worn. General causes of fouling are excessive oil,
use of non-recommended injection oil, improper use of the choke, or
incorrect carburetion adjustments.