2009 Polaris Sportsman 850 XP EFI EPS Service Manual, Page 118Get this manual
ENGINE ENGINE DISASSEMBLY AND INSPECTION
Valve CoverBreather Valve
123Remove (2) breather housing bolts (A)Inspect bellows (B) for cracks (not required for valve cover removal)Remove (6) rocker cover bolts (C) and isolators (D)Replace isolators and gasket (E) if oil leaks are evident
Rocker CarrierCamshaft Removal
1Rotate engine in direction of rotation until pin (A) is facing UPRotate cam another 60 to the 10:00 position to relieve valve spring pressure from camshaft lobes