2016 Polaris POLARIS ACE 900 SP Owners Manual - Page 90

MAINTENANCE Spark Plugs Spark Plug Inspection 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 plugs for correct color. See page 88. CAUTION! A hot exhaust system and engine can cause burns. Wear protective gloves when removing a spark plug for inspection. 1. Remove the cargo box access panel. Air Box Cover Removed 2. Remove the air box cover. 3. Remove the spark plug cap. 4. Using the spark plug wrench provided in the tool kit, remove a plug by rotating it counter-clockwise. 5. Reverse the procedure for spark plug installation. Apply anti-seize compound to the spark plug threads. 6. Torque to specification. See page 87. Spark Plugs 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. The tip should not be white. A white insulator tip indicates overheating, caused by use of an improper spark plug or incorrect throttle body 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 oil or poor fuel quality. 88