2009 Polaris Scrambler 500 4x4 2x4 factory service manual, Page 83Get this manual
ENGINE 3Remove cam chain (B)Inspect chain for worn or missing rollers or damageStretch chain tight on flat surface and apply 10 lb(4.53 kg) loadMeasure length of 20 pitch section of chainReplace if worn past service limitChain Service Limit: 5.407 (13.7 cm) 4Using the special socket, remove the crankshaft slotted nut (A)NOTE: The slotted nut is left hand thread5Remove cam chain drive sprocket (B) and Woodruff key from crankshaft6Inspect sprocket teeth for wear or damage7Inspect Woodruff key for wear8Replace any worn or damaged parts3Inspect valve for wear4Check seat area for nicks or foreign material that may prevent proper sealing of valve
One Way Valve Spring Free Length: Std: 1.450 (3.68 cm)
CRANKCASE SEPARATION