2008 Polaris ATV Sportsman 300 400 H.O. Service Manual, Page 43Get this manual
MAINTENANCE Spark Plug Service
Sportsman 300 Removal 1Remove the seat and left hand side panel to access the spark plugSpark Plug InspectionInstallation 1Inspect electrodes for wear and carbon buildupLook for sharp outer edge with no rounding or erosion of the electrodesInspect electrode for wear and buildup
2Spark Plug
Clean with electrical contact cleaner or glass bead spark plug cleaner onlyCAUTION: wire brush or coated abrasive should not be usedMeasure gap with wire gaugeRefer to specifications in the following illustration for proper spark plug type and gapAdjust gap if necessary by carefully bending the side electrodeSpark Plug GapRemove spark plug high tension leadClean plug area so no dirt and debris can fall into engine when plug is removedUsing the special wrench provided in the tool pouch, remove the spark plugSportsman 400 H.ORemoval 123Remove the seat and right hand side panelRemove the fuel tank coverRemove the spark plug cap (if necessary, use needle-nose pliers to assist)Clean plug area so no dirt and debris can fall into engine when plug is removedUsing 58" socket with long extension, access the spark plug through the fuel tank cover openingSportsman 400 H.OGap.035" (0.90 mm) 4If necessary, replace spark plug with proper typeCAUTION: Severe engine damage may occur if the incorrect spark plug is usedApply small amount of anti-seize compound to the spark plug threadsInstall spark plug and torque to 9-11 ftlbs(12-15 Nm)To install, reverse the removal procedureSportsman 300 Gap.031" (0.80 mm)