2008 Polaris ATV Sportsman 300 400 H.O. Service Manual, Page 62Get this manual
ENGINE (300) Rocker ArmRocker Arm Shaft Disassembly and Inspection
NOTE: Orientation of the components is important during engine reassemblyMark all components before disassembly1Remove the valve coverBe sure engine is positioned at TDC on the compression stroke (there should be clearance on both rocker arm adjusters)4Inspect each rocker arm cam follower surfaceIf there is any damage or uneven wear, replace the rocker armNOTE: Always replace camshaft if lobe of either rocker arm is worn or damaged
Inspect surface of followers