Polaris 9920787 Offroad Vehicle User Manual


 
97
MAINTENANCE
Spark Plugs
Spark Plug Inspection
4. Inspect the electrodes for wear
and carbon buildup. Replace
worn or fouled plugs. Verify that
the gap is at specification before
installation.
5. Reverse the procedure for spark
plug installation. Torque to
specification.
Spark Plug Condition
Normal Spark 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 indi-
cates the proper type and heat range for the engine and the service.
NOTE: The tip should not be flaky and white. A white insulator tip indicates
overheating, caused by use of an improper spark plug or incorrect
carburetion adjustments.
Wet Fouled Spark 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 oil, improper use of the choke, or incorrect throt-
tle body/carburetor adjustments.