Polaris Series 10 Ranger 425 2x4 - Manual (Page 91)

89
MAINTENANCE AND LUBRICATION
Spark Plugs
S
Proper electrode gap is .036″/.90mm.
S
Spark plug torque is 14 ft. lbs./19 Nm.
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Use NGK BKR5ES spark plugs.
Spark plug condition is indicative of engine operation. The spark plug
firing end condition should be read after the engine is warmed up and
the vehicle is driven at higher speeds. Immediately check the spark
plug for correct color.
1. Normal
The 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.
2. Wet Fouled
The 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 are excessive oil, improper use
of the choke, or incorrect carburetion adjustments.